On paper, a non-contrast head CT looks like one of the easiest things a radiology team will ever bill. One scan, one code, done. In practice, CPT code 70450 sits inside a three-code family where a single same-day decision running a second scan with contrast can flip a perfectly correct claim into a denied one.

This guide covers what the code actually describes, when to reach for it instead of its siblings, which modifiers belong on it, the bundling rule that trips up even experienced coders, and how reimbursement is built. The goal is fewer denials and cleaner claims, not a glossary.

What CPT Code 70450 Covers

CPT code 70450 reports a diagnostic computed tomography (CT) scan of the head or brain performed without contrast material. It lives in the head-and-neck diagnostic radiology range. “Without contrast” means no iodinated dye was injected to highlight blood vessels or tissue; the study relies on standard X-ray attenuation alone, imaging from the vertex of the skull down to the foramen magnum.

Its job is to give clinicians a fast first look when something acute is suspected in the brain bleeding, trauma, stroke, or pressure changes. CT is high-volume work, too: according to UCSF research reported by NPR, about 93 million CT exams were performed in the United States in 2023, and head imaging is among the most common reasons patients enter the scanner.

Where 70450 Sits in the Head CT Code Family

The most common 70450 mistake starts with confusing it with the two codes next to it. The contrast status is the entire difference:

Keep one more code in view: 70496 is CT angiography of the head, a separate study performed with contrast to evaluate vessels. It is not interchangeable with 70450, even when both are ordered together. Mislabeling these imaging studies is exactly the kind of error that drives radiology denials, which is why specialized radiology billing lean so heavily on coders who know the contrast-status distinctions cold.

When to Use CPT Code 70450

A non-contrast head CT is the preferred first-line image in several urgent situations: acute head trauma, sudden severe headache, suspected intracranial or subarachnoid hemorrhage, acute stroke or TIA, new-onset seizure in an unstable patient, and suspected hydrocephalus. In each case, contrast is not needed for that initial read fresh blood and gross structural changes show up clearly on a plain CT, and skipping contrast keeps the scan fast and avoids dye-related risk.

Acute Head Trauma in the ER

A patient arrives after a fall, confused and complaining of a headache. The emergency physician orders a head CT without contrast to rule out an intracranial bleed or skull fracture. The technologist performs the scan, and the service is reported with 70450 paired with the appropriate head-injury ICD-10 code.

Sudden Severe Headache

A patient describes the worst headache of their life with neurologic changes. The team suspects a subarachnoid hemorrhage and orders a non-contrast CT first, because acute blood is best seen without dye. Subarachnoid hemorrhage is uncommon roughly 10 to 14 cases per 100,000 people each year in the U.S., according to StatPearls (NCBI) but it is time-critical, which is why the plain CT comes first.

Suspected Acute Stroke

When a patient presents with sudden neurologic deficits, a non-contrast head CT is the standard tool to separate a hemorrhagic stroke from an ischemic one before any treatment begins. That single distinction changes the entire care path, and it is made on a 70450 study.

Technical, Professional, and Global Billing

Like most imaging codes, 70450 can be split into two parts: the technical work of running the scanner and the professional work of interpreting the images. How you bill depends on who did what.

Global Billing

When one entity both owns the equipment and reads the study, report 70450 with no component modifier. The single code covers the whole service.

Modifier TC

Append modifier TC when your facility performed the scan but a separate provider interpreted it. TC bills only for the equipment, staff, and supplies.

Modifier 26

A radiologist who interprets a scan performed somewhere else reports 70450 with modifier 26 for the read alone. Worth noting for imaging centers: a diagnostic non-contrast head CT requires only general physician supervision, a lighter requirement than the direct supervision contrast studies carry.

The NCCI Bundling Trap Most Coders Miss

Here is the rule that causes the most avoidable 70450 denials, and the one most quick guides skip entirely. When a non-contrast head CT (70450) and a contrast head CT (70460) are performed on the same day, in the same session, for the same clinical indication, you do not bill both codes. You bill the combined study code, 70470.

Under National Correct Coding Initiative (NCCI) edits, if 70450 and 70460 are reported together, 70460 is treated as the payable Column 1 code and 70450 becomes the Column 2 code that gets denied. The edit carries a modifier indicator of 1, meaning it can be bypassed only when criteria for a genuinely separate service are met.

The nuance matters. Code 70470 is correct only when the without-then-with study was a single planned protocol from the start. If the contrast scan happened later as a distinct encounter for a new clinical question a different order, a different indication then reporting 70450 and 70460 separately with an appropriate distinct-encounter modifier (such as XE) can be the accurate choice. The documentation has to support which story is true.

Other Modifiers That Apply to 70450

Modifier 76: Repeat Procedure, Same Day

Use modifier 76 when the same provider repeats a non-contrast head CT on the same day for medical necessity for example, to track an evolving bleed. It tells the payer the second scan was intentional, not a duplicate claim.

Modifier 77: Repeat by a Different Provider

When a different provider repeats the scan, modifier 77 applies instead. It serves the same purpose as 76 but signals that the repeat read or study came from someone else.

The X{EPSU} Modifiers Versus 59

When you need to show that 70450 was a distinct service from another procedure on the same day, the specific X modifiers XE (separate encounter), XS (separate structure), XP (separate practitioner), XU (unusual non-overlapping service) are preferred over the broad modifier 59. They tell the payer exactly why the services were separate, which holds up far better under review.

Reimbursement and Documentation Essentials

How 70450 Pays

There is no single flat price. Medicare builds payment from relative value units (RVUs) for physician work, practice expense, and malpractice, then adjusts each by the local Geographic Practice Cost Index and multiplies by the annual conversion factor. Because the code splits into technical and professional components, the site of service shifts the math: physician payment is usually lower in a facility setting, where the facility bills the technical side separately. Commercial payers commonly reimburse somewhere in the range of 120 to 200 percent of the Medicare rate. Always price against the current Medicare Physician Fee Schedule rather than a fixed figure, since the conversion factor and RVUs change every year.

Documentation That Survives an Audit

Clean payment depends on a record that defends the study. At minimum it should include the physician order specifying a head CT without contrast, the clinical indication and symptoms with matching ICD-10 codes, explicit confirmation that no contrast was used, who performed and who interpreted the scan, and the findings. Repeatedly billing 70450 without strong clinical justification is a known audit red flag, so the indication has to be visible on every claim.

Prior Authorization and Coverage

Check the relevant Local Coverage Determination before billing head and neck CT imaging falls under LCD L37373, which lists covered diagnoses. Emergent scans rarely need prior authorization, but elective and repeat imaging often do, and many commercial plans apply their own rules. Verify the payer policy rather than assuming. For practices weighing whether to manage this in-house, our overview of the top medical billing companies walks through what to look for in a billing partner.

Common Reasons 70450 Claims Get Denied

Most denials on this code trace back to a short, predictable list:

• Billing 70450 when contrast was actually used that should be 70460.
• Reporting 70450 and 70460 together instead of the combined code 70470.
• Missing or mismatched ICD-10 codes that fail to justify medical necessity.
• No documentation confirming that contrast was withheld.
• Repeat scans submitted without modifier 76 or 77.
• Ignoring prior-authorization requirements on elective or repeat imaging.

Conclusion

CPT code 70450 earns its place as the fast first read for head trauma, suspected bleeds, and stroke. The code itself is simple; the denials almost never come from the scan and almost always come from the contrast distinction and the 70470 bundling rule. Get those two things right, document why contrast was withheld, and most 70450 claims pay cleanly on the first pass.

If imaging denials are draining revenue your practice has already earned, it pays to work with coders who handle these edits daily. Nexus io radiology billing services pair AAPC-certified radiology coders with payer-specific claim edits to keep studies like the non-contrast head CT moving from order to payment.

Frequently Asked Questions

What is the difference between CPT 70450 and 70460?

70450 is a head CT performed without contrast; 70460 is the same study performed with contrast. The contrast status is the only thing that separates them.

Can I bill 70450 and 70460 on the same day?

Usually not. A same-session without-then-with study is reported as the combined code 70470. Only when the contrast scan is a genuinely separate later encounter can the two be billed separately, and then a distinct-encounter modifier such as XE is needed.

Does 70450 include CT angiography of the head?

No. CT angiography of the head is reported with 70496, a separate code. A non-contrast CT and a CTA are different studies even when ordered together.

When do I use modifier 26 versus TC with 70450?

Use modifier 26 when billing only the interpretation, TC when billing only the scan itself, and no component modifier when one entity provides the complete global service.

Does Medicare require prior authorization for 70450?

Emergent use often does not, but elective and repeat imaging may, and many commercial plans have their own requirements. Confirm the specific payer policy before the scan when possible.

Gastroenterology billing stands apart from most specialties because the gastrointestinal tract spans multiple organs, each carrying its own CPT code families, modifier rules, documentation thresholds, and payer-specific requirements. For example, when billing for an esophageal motility study, you must make component billing decisions, consider NCCI bundling risks when billing for pH monitoring and endoscopy codes, and meet the shifting requirements for medical necessity under the requirements of Medicare, Medicaid, and commercial carriers.

That complexity is exactly why the billing team at Nexus io created this guide to break down one of the most commonly billed yet frequently denied gastroenterology procedure codes. This guide explains the official CPT descriptor for code 91010, clinical scenarios that validate the study with ICD-10-CM links, all modifiers applicable, including those in the CMS subset that so many other guides do not cover, NCCI bundling edits that result in most claim denials, and what documentation and reimbursement standards will be in effect in 2026.

If your practice bills esophageal manometry and you want to stop leaving revenue on the table, this guide covers what you need to know.

CPT Code 91010 – Description

CPT code 91010 falls within the “Upper Gastrointestinal Motility Studies” range, maintained by the American Medical Association (AMA). The code encompasses both the professional and technical components of esophageal manometry.

During the procedure, the physician advances a pressure-sensing catheter through the nose into the esophagus and gastroesophageal junction (GEJ) to assess esophageal muscle movement. The physician will then be able to use HRM metrics recorded throughout the study to interpret the findings according to the CCv4.0, including IRP, DCI, and DL. A written report will be completed by the physician to finalize the findings.

Scenarios Where CPT Code 91010 is Applicable

GERD Evaluation with Refractory Symptoms

Patient reports constant burning sensation in the retrosternal area (heartburn), experience of acidic fluid in throat (regurgitation), and sharp pain just behind the sternum (retrosternal pain) despite appropriate PPI therapy. Manometric evaluation provides data about the lower esophageal sphincter (LES) competence (i.e., functioning) and peristaltic function to determine surgical candidacy for fundoplication.

Results of the study demonstrate decreased resting LES pressure and ineffective esophageal motility (IEM). Code report as 91010 with ICD-10-CM codes K21.0 (GERD with esophagitis) or K21.9 (GERD without esophagitis).

Confirming Achalasia

A patient with progressive dysphagia to solids and liquids after endoscopy excludes mucosal pathology. HRM demonstrates absent peristalsis with elevated IRP, consistent with Type I achalasia under CCv4.0. Report with K22.0 (achalasia of cardia). After diagnosis has been established, treatment can be determined based upon the diagnosis given: either pneumatic dilation, Heller myotomy, or per-orifice endoscopic myotomy (POEM).

Pre-Operative and Post-Fundoplication Assessment

For any type of Nissen, Toupet, or Dor fundoplication procedure, performing manometry is required prior to determining if the patient has sufficient peristaltic reserve. This helps to rule out achalasia as a contraindication that would prevent performing a full 360-degree fundoplication wrap on the patient.

Post-operatively, manometric evaluation can be helpful in establishing the cause of recurrence of dysphagia, either related to wrap failure or dysmotility following surgery. This assessment would be coded either R13.10 (dysphagia, unspecified) or R13.19 (other dysphagia).

Cardiac Chest Pain

After a cardiac evaluation demonstrates that chest pain is not due to ischemia, manometric examination will reveal disorders affecting motility within the esophagus; including distal esophageal spasm (DES: defined as having 20% or greater premature contractions with a DCI greater than 450 mm Hg·s·cm based upon CCv4.0), jackhammer esophagus (defined as hyper-contracted with a DCI in excess of 8000 mm Hg·s·cm), and lack of contractability. This assessment will be coded using R07.89 (other chest pain) or K22.4 (dyskinesia of esophagus).

Applicable Modifiers for CPT Code 91010

Modifier 26 

This modifier bills the professional component only: physician interpretation and written report. 

Modifier TC 

Modifier TC bills the technical component. It includes procedure execution, catheter, manometry equipment, and staff. No other modifier is required when a single entity performs and interprets the study globally.

Modifier 52 

This modifier reports a study reduced in scope (fewer swallows than the CCv4.0 protocol defines).

Modifier 53 

It is for reporting a study that was initiated but discontinued due to patient distress or clinical risk.

Modifier 76 

This modifier indicates same-physician same-day repeat; Modifier 77 indicates different-physician same-day repeat.

Modifier 59 

The NCCI bundling edit for 91010 is now an exception when the procedure is considered different than the same-day pH monitoring or endoscopy. The Centers for Medicare & Medicaid Services (CMS) prefers the specificity of modifiers: XE (separate encounter), XS (separate structure), XP (separate practitioner), and XU (unusual non-overlapping service); instead of 59, which may subject the provider to additional scrutiny for audit purposes.

By using XE or XS, the modifier usage will have less likelihood of triggering additional audits and will provide a concise and well-supported clinical rationale for services billed. Any organization exhibiting consistent modifier errors in its gastroenterology billing should prioritize a more in-depth training of their coders regarding these modifier distinctions.

NCCI Bundling Edits and Denial Triggers

NCCI procedure-to-procedure (PTP) edits generate the majority of 91010 denials, and most billing guides omit this entirely.

91010 vs. 91013

CPT code 91013 (esophageal motility study utilizing perfusion or stimulation) is considered an add-on code to 91010. When stimulation occurs, 91013 must be billed in conjunction with 91010 and may not be additionally billed as a standalone because the base study is included. Billing 91013 as a standalone code without 91010 will cause an automatic denial.

91010 vs. pH monitoring codes

When submitting codes 91034 (nasal catheter pH electrode), 91035 (Bravo capsule), 91037 (impedance with nasal catheter), and 91038 (impedance with mucosal electrode), the same day as 91010, an appropriate documentation of a clinical necessity for the submission of an additional code using modifier 59 or XE/XS must be contained in the records. 

Note: NCCI edits have been applied since January 2022 to 91038 to bundle with the submission of 91034. The documentation and billing for the same-date submission of any of the three will require diligent documentation and adjustment/billing of a modifier. 

91010 vs. endoscopy codes

The same guidelines apply when submitting 91010 with EGD code submissions (i.e., 43235, 43239, 43249) on the same date of service, and appropriate documentation must be present in the medical record indicating a medical necessity for submitting each procedure using modifier 59 or XS is necessary. 

Medically Unlikely Edits (MUE)

The MUE for 91010 is one unit per provider per date of service. A provider submitting for greater than 1 unit for 91010 would cause an automatic denial regardless of the modifier used. 

CPT Code 91010 – Billing and Reimbursement Guidelines

Establish Medical Necessity

Clinical indication must be provided. Diagnoses of GERD being treatment resistant, Achalasia suspected, checking motility prior to Fundoplication, and unexplained dysphagia after all structural defects have failed to explain. The ICD-10-CM codes available to show medical need include: K21.0/K21.9 (GERD), K22.0 (Achalasia), K22.4 (DES), R13.10-19 (Dysphagia), and R07.89 (Chest Pain). Some payers also accept K20.0 and K20.9 if being run as part of the EoE workup; however, it is best to verify that your MAC posts a Local Coverage Determination (LCD) that would allow you to bill these.

Ensure Comprehensive Documentation

You will have to document the type of catheter used, which position the patient was in at the time of the cath; which swallows were done according to the swallow protocol, and whether there were complications with the procedure. You must include, but may not be limited to, LES pressure, IRP, DCI, distal latency, Peristaltic classification, and an overall impression of testing according to the Chicago Classification 4.0 – all tests must be interpreted completely, or there will be post-payment audit clawbacks on motility testing.

Payer-Specific Policies

Medicare coverage varies by MAC jurisdiction. The CY 2026 PFS conversion factor is $33.40 (non-qualifying APM, +3.26% over 2025) with a finalized negative 2.5% efficiency adjustment on certain diagnostic valuations. The rate of prior authorization for commercial payers like UnitedHealthcare, Aetna, Cigna, and BCBS is typically required, and some will require a prior endoscopy before allowing payment for a manometry study. Timely filing limits will fall between 90 days for commercial and 12 months for Medicare. Practices weighing whether to manage billing in-house or outsource should factor in this complexity.

Summary

This guide covered CPT 91010 under the CCv4.0 framework, four clinical scenarios with ICD-10-CM linkages (K21.0, K21.9, K22.0, K22.4, R13.10–R13.19, R07.89), seven modifiers plus CMS subset modifiers XE through XU, NCCI PTP edits between 91010 and codes 91013, 91034, 91035, 91037, and 91038, MUE thresholds, and 2026 Medicare and commercial payer reimbursement guidelines.

When every 91010 claim requires correct component splitting, CCv4.0-compliant documentation, NCCI edit navigation across five related procedure codes, and payer-specific LCD verification, the margin for coding error is nearly zero. Achieving that type of accuracy with a general billing staff cannot be done consistently. Nexus io focuses solely on the complexities of gastroenterology billing using AAPC-certified coders who specialize in motility study documentation and artificial intelligence to scrub a claim on the front end for any bundling conflicts or modifier errors prior to submission. 

As a result, their entire clientele has experienced a first pass clean claim rate of 98%, a collection ratio of 97%, 30% reduction in AR days, and an average of 30% revenue growth in the first several months of their relationship. Talk to the experts at Nexus io to see how their gastroenterology billing services handle the codes your practice bills most.

Frequently Asked Questions

What is the difference between CPT 91010 and 91013? 

CPT Code 91010 represents the basic study of esophageal manometry, while CPT code 91013 is only used in conjunction with code 91010 when any type of stimulation or perfusion (acid, alkali, or IV medication) occurs during the procedure. 

Does CPT code 91010 require a modifier? 

No, not if you have billed for the service as the global provider. You must use either modifier 26 or TC if you have split the professional and technical components between different providers. There are certain modifiers (52, 53, 59, 76, 77, XE, XS, XP, XU) that can be used depending on the specific situation.

Is CPT 91010 a surgical procedure? 

No, the code is considered a diagnostic procedure and has an indicator of XXX in the Medicare Physician Fee Schedule, which means that it does not have a global surgery period.

Can 91010 be billed the same day as upper endoscopy? 

Yes, as long as you have attached either modifier 59 or XS to 91010 and have documented that the esophageal manometry (91010) and upper endoscopy (43235, etc.) were for different clinical indications.

CPT Code 91035 refers to wireless esophageal pH monitoring using a Bravo™ capsule that is attached to the mucosa (the membrane lining the esophagus). For billing purposes, the time of service for CPT Code 91035 is the date of interpretation instead of placement. When reported same-day as EGD (43235) at the facility level, Modifier 59 is required per 2026 NCCI edits.

According to the American College of Gastroenterology (ACG) data, approximately 20% of adults in the United States suffer from GERD. Patients who are experiencing refractory symptoms, or atypical manifestations, or are being evaluated for surgical intervention need to have confirmation of acid reflux in order for their physician to make a diagnosis. The Bravo capsule is a device used to monitor the pH level (the amount of acid) within the esophagus of suspected cases of GERD, primarily because patients are unable to tolerate having a catheter placed in their noses. 

This guide serves as a compliant, audit-defensible reference for gastroenterologists, GI coders, and compliance teams.

CPT Code 91035 – Description

The AMA CPT codebook categorizes CPT code 91035 in the Gastroesophageal Reflux Test Studies section. Its full descriptor reads: Esophagus, gastroesophageal reflux test; with mucosal attached telemetry pH electrode placement, recording, analysis, and interpretation.

CPT Code 91035 features a wireless, mucosal-contacting capsule that allows long-term measurement and monitoring of acid exposure. CPT91034, however, refers to a wired (transnasal) pH testing with a catheter attached to the nasal mucosa. CPT 91035 is typically preferred for patient comfort and its ability to record data for up to 96 hours, whereas 91034 is limited to a 24-hour wired connection.

The capsule is placed approximately 6 cm above the squamocolumnar junction (Z-line) per ACG placement standards, using endoscopy (EGD), and records acid exposure over 24 to 96 hours.

The pathologic acid exposure time (AET) is greater than 6% at pH less than 4, as described in the Lyon Consensus (updated 2024), and AETs between 4% and 6% are considered borderline qualification for diagnosis.

The unique features of CPT code 91035 include:

• pH monitoring is performed by attaching to the mucosa at the Z-line instead of through a transnasal catheter
• Documentation must include the Symptom Index (SI), Symptom Association Probability (SAP) to quantify the temporal relationship between the patient’s symptoms and reflux events.
• The technical aspects (placement and recording) and professional aspects (analysis) are covered by one bill under a global format
• Billed on the interpretation date, not the date of capsule placement
• Document a 7-to-14-day PPI washout period in the clinical record
• If ordered after a negative EGD or for patients with refractory GERD, then the medical necessity must be demonstrated.

The capsule is placed on Day 1 (EGD date) while the physician interprets the data 48–96 hours later. In this instance, CPT code 91035 is used, and the equipment is owned by the physician. When billing is performed separately, i.e. quality modifier 26 and technical modifier TC will be reported as well.

Scenarios Where CPT Code 91035 is Applicable

CPT Code 91035 for GERD with Failed PPI Therapy

A patient with confirmed GERD (ICD-10: K21.0) presents with persistent heartburn despite twice-daily PPI therapy for 12 weeks. Bravo pH monitoring will be performed following a documented PPI washout period, in order to determine the extent of acid exposure time, and medical necessity is particularly supported when the pH monitoring occurs after a negative endoscopy. CPT code 91035 is reported on the interpretation date, and Modifier 59 is appended to 43235 on the facility claim per 2026 NCCI requirements.

CPT Code 91035 for Pre-Operative Anti-Reflux Surgery Evaluation

A patient with chronic GERD is being considered for laparoscopic fundoplication. According to ACG Clinical Guidelines, Objective pH documentation is required prior to surgery. Bravo monitoring will be performed with the patient off PPIs with a documented PPI washout period, and the documented pathologic AET will be included in the note to support surgical candidacy. CPT code 91035 applies when documentation links the pH result to surgical candidacy determination.

CPT Code 91035 for Atypical and Extraesophageal GERD Manifestations

A patient arrives with a cough (ICD-10: R05.9), wheezing (ICD-10: R06.2), and laryngopharyngeal reflux (ICD-10: J39.3 that have not improved using the recommended patient treatment of inhalers only. The wireless pH readings have shown excess nighttime acid, therefore, 95% threshold, confirming pathologic reflux as the extraesophageal driver.

CPT code 91035 is reported on the interpretation date. ICD-10 codes R05.9, R06.2, or J39.3 support medical necessity depending on the primary documented indication.

CPT Code 91035 for Post-Bariatric Surgery Reflux Recurrence

A patient six months post Roux-en-Y gastric bypass presents with recurrent heartburn. A Bravo™ pH study confirms that the patient still has a significant amount of acidic exposure with a higher-than-normal DeMeester score. This information directly affects the plan to initiate treatment with PPIs. CPT code 91035 is appropriate using ICD-10 K91.89 or K21.0, depending on clinical documentation specificity.

Common Modifiers Used with CPT Code 91035

CPT Code 91035 – Medicare Reimbursement Guidelines 

Medicare Part B provides CPT code 91035 coverage in accordance with medical necessity requirements. For CY 2026, the conversion factors that CMS has finalized are $33.57 for qualified alternative payment model participants and $33.40 for other non-APM clinicians. 

Geographic area and whether the service was delivered in a facility or not will also impact reimbursement levels. Providers must confirm their rate via the CMS MPFS Lookup Tool and ensure they meet the MAC LCD criteria prior to billing.

Demonstrate Medical Necessity

Medical necessity will be established through the documentation that contains a qualifying diagnosis and how the pH test will impact clinical management. There are several indications in which CPT code 91035 may be billed; these include atypical GERD symptoms (chronic cough [R05], wheezing [R06.2], LPR) and assessment for esophageal acid exposure in patients being evaluated as bariatric surgical revision candidates.

Focus on Documentation Completeness

The following items must be submitted with each CPT code 91035 claim: prior PPI failure history, Bravo™ confirmation of mucosal attachment at the Z-line, monitoring length of time, AET %; DeMeester score; symmetry index (SI), symmetry assessment (SAP); total number of reflux episodes, and an interpretive report that has been signed and dated on the interpretation date. The two most common triggers for audits are missing signed reports or failure to confirm the wireless attachment method of the mucosa.

Understand Payer Policies

There are many commercial payers that consider wireless pH monitoring as an investigational procedure for some indications. The pre-authorization process differs from payer to payer. Providers should verify the payer’s specific coverage annually and obtain proper pre-authorization for any procedure that requires it.

Common Claim Denial Reasons for CPT Code 91035

Comparisons with Related CPT Codes

Conclusion

CPT code 91035 demands precision across all compliance dimensions: Z-line attachment documentation, interpretation-date billing, NCCI-compliant EGD unbundling, and ICD-10 specificity with documented PPI washout and failed conservative management. Gaps in any of these areas can be the cause of denial and audit exposure. Missing written report, incorrect service date, and unbundled claims for EGD on the same day are the most common causes of denial for Nexus io within high volume GI practices. Nexus io AAPC certified coding experts have an extensive background in providing gastroenterology billing services related to everything from the Bravo™ pH monitoring service entry and NCCI edits to the denial appeals and MAC LCD compliance. Explore Nexus io medical billing services and connect with the team today to close revenue gaps before they compound.

Frequently Asked Questions

Does Medicare Cover CPT Code 91035?

CPT code 91035 is billable under Medicare Part B if certain conditions of medical necessity and applicable ICD-10 diagnosis are met. Providers are required to verify current MAC Local Coverage Determination criteria for appropriate billing, and also the 2026 locality adjusted rates under the Medicare Physician Fee Schedule. 

Some of the more commonly accepted diagnoses for CPT code 91035 include K21.0, K21.9, R12 (Heartburn), R05 (Chronic Cough), R06.2 (Wheezing), J39.3 (Laryngopharyngeal Reflux), J45.x (Asthma associated with documented Extraesophageal Gastroesophageal Reflux), and K91.89 (Post-procedural GI Complication).

Can CPT Code 91035 Be Billed on the Same Day as EGD Code 43235?

Yes. When the EGD (esophagogastroduodenoscopy) is medically necessary and performed independently of the capsule, and not solely for placing the Bravo™ capsule. The modifier 59 will need to be appended to the 43235 at the facility level; however, CPT code 91035 should be reported on the date of the interpretation. 

Are CPT Codes 91035 and 91034 Billable Together?

The two CPT codes function as mutually exclusive alternative methods for ambulatory esophageal pH monitoring; therefore, billing both codes would be contrary to NCCI bundled billing guidelines, as unbundling. 

What Is the Billing Difference Between CPT Codes 91035 and 91037?

CPT 91035 measures pH using a wireless Bravo™ capsule, whereas 91037 measures both pH and intraluminal impedance using a nasal catheter; therefore, the use of 91037/91038 combined is preferred for patients continuing to have symptoms while on PPI therapy.

According to the American Association for the Study of Liver Diseases (AASLD), chronic liver disease and cirrhosis account for more than 40,000 deaths annually in the United States. These stats highlight the clinical urgency of accurate hepatic fibrosis staging. 

Non-invasive liver stiffness evaluations have become a primary component of today’s gastroenterology practices. CPT Code 91200 is the billing code for non-invasive liver stiffness assessments. This code denotes liver elastography using shear wave (i.e., vibration) elastography with mechanical stimuli to produce data without visual images, along with their interpretations and reports for each test performed. 

To effectively use this code, gastroenterology practices must have a basic understanding of the specific scope of the procedure being performed, modifier logic, the specificity of ICD-10 codes, payer-specific (local) coverage determinations (LCD), and proper documentation format. This guide serves as a compliant, audit-defensible coding reference for physicians, GI coders, and healthcare compliance teams.

CPT Code 91200 – Description

CPT code 91200 is classified under Other Diagnostic Gastroenterology Procedures in the AMA CPT codebook. It describes liver stiffness measurement performed through non-imaging vibration-controlled transient elastography (VCTE), commercially performed via the FibroScan® device.

CPT code 91200 for elastography has important distinguishing features compared to more common elastography codes, including:

• No B-mode imaging can be included in the medical record – please note this.
• The procedure includes technical performance of the procedure and physician interpretation and reporting when billed as a global bill; both must be documented in the medical record.
• Stiffness is defined by a numerical kPa value. An established staging system, such as METAVIR (staging criteria from F0 to F4) can be used to compare a patient’s stiffness kPa value with the published normal kPa range for liver tissue.
• Documentation of the interquartile range divided by median (IQR/M) must be provided, with an IQR/M of ≤0.30 expected to confirm the appropriate technical performance of this test.

Clinical research has validated the use of the FibroScan® elastography procedure as an effective diagnostic tool. FibroScan® has shown an accuracy of approximately 87% in detecting significant hepatic fibrosis and 91% in excluding advanced liver scarring. These data offer a strong medical necessity determination for the use of elastography in inpatient and outpatient settings.

Scenarios Where CPT Code 91200 is Applicable

Liver Fibrosis Staging in Chronic Viral Hepatitis

A patient who has chronic hepatitis C (ICD-10: B18.2) would require hepatic fibrosis staging before the doctors begin antiviral therapy. The gastroenterologist documents the rationale for deferring liver biopsy and orders VCTE instead. 

Using CPT code 91200 for VCTE in this case is appropriate, and it is important to provide supporting documentation indicating that there should be no B-mode images ordered, the IQR/M ratio must be provided, and there must be linkage to the qualifying ICD-10. The same rationale applies when evaluating patients with either chronic hepatitis B (ICD-10: B18.0; B18.1).

NAFLD and NASH Treatment Response Monitoring

A patient with documented Non-Alcoholic Steatohepatitis (NASH) is currently undergoing a pharmacologic and lifestyle regimen and being monitored for treatment response via serial assessments of VCTE each year to monitor the patient’s fibrosis regression/progression. 

Each assessment can be billed for separately using CPT code 91200. If there is a medical justification for a repeat assessment of VCTE on the same date (due to independent clinical reasons), modifier 91 should be applied. Each session’s documentation must support the service’s medical necessity on an individual basis and not be ordered based on routine clinical reflex alone.

Background Fibrosis Assessment in Chronic Alcoholic Liver Disease

A patient who has been diagnosed with chronic alcoholic liver disease (ICD-10: K70.x) is undergoing a pre-surgical evaluation to assess the risk of developing cirrhosis. Without performing a biopsy, the patient is going to have non-imaging elastography performed to quantify the hepatic fibrosis present on the patient. 

The kPa is a direct result of quantifying the hepatic fibrosis, and it will guide the appropriate treatment pathway. CPT code 91200 will be the appropriate billing code, and ICD-10 coding on K70.0-K77, as well as R94.5 (abnormal liver function test), will support the medical necessity for services rendered

Evaluating Benign vs. Malignant Hepatic Lesions

Imaging has detected a concerning liver mass located in a person who has chronic liver disease. Non-imaging elastography of the liver is being ordered to assess the overall hepatic stiffness and overall co-factor risk for cancer. 

If the non-imaging (91200) elastography is evaluating for overall liver stiffness, the report must include a clear link between the clinical objective and the coded diagnosis. If the elastography is lesion-specific (76982) and performed with concurrent ultrasound imaging, then the report should not use (91200) as the code.

Common Modifiers Used with CPT Code 91200

The following modifiers govern accurate claim submission and prevent NCCI bundling errors:

When the physician and facility split the global service, Modifier 26 and Modifier TC must never appear on the same claim line. Each component is submitted independently.

CPT Code 91200 – Medicare Reimbursement

CPT code 91200 is a covered service under Medicare Part B when medical necessity criteria are met. Reimbursement is governed by the Medicare Physician Fee Schedule (MPFS). In the recently published CY 2026 reimbursement report, CMS has determined that the conversion factor is $33.57 for participants in qualified Advanced Alternative Payment Models (APM) and $33.40 for other eligible physicians, which will result in a Congressional increase of 2.5% over the 2025 rates. 

The payment rate for CPT 91200 may vary depending on geographic Practice Expense adjustment, GPCI value, and if billed in a facility or non-facility setting. The current rate should also be verified by utilizing the CMS MPFS Look-Up Tool and checking against each respective MAC Local Coverage Determination (LCD).

Medical Necessity

To establish medical necessity, documentation must have an appropriate ICD-10 diagnosis and specify how the liver stiffness result applies to clinical management. The clinical note should provide the following:

• ICD-10 references that confirm a chronic liver disease diagnosis 
• Justification for selecting VCTE (non-imaging), rather than biopsies or imaging elastography
• The effect of the result (from the procedure) on the patient’s treatment regimen

Coverage for claims under major commercial payers is generally limited to chronic hepatitis B, C, alcoholic liver disease, and other chronic liver diseases under active clinical management.

Focus on Documentation Completeness

To submit an itemized claim with CPT Code 91200 requires complete documentation of the following items in your clinical records:

• Confirmation that no B-mode ultrasound was performed
• The number of valid acquisitions for testing (typically 10)
• The liver stiffness score, expressed in kilopascals (kPa)
• The IQR/M ratio, with a value of less than or equal to 0.30, shows technical adequacy.
• The written report from the physician interpreting the results of this test for fibrotic staging
• The written report from the physician should be physically included in the medical record.

If any of the above items are not documented as part of your claim’s documentation, then the claim will be flagged as under-documented, creating exposure to post-payment audit recoupments.

Understand Payer Policies

Medicare Advantage plans, commercial payers, and Medicaid programs apply independent coverage criteria to CPT code 91200. Most major commercial payers limit the frequency of this test to every 12 months, unless the patient has documentation of disease progression. Additionally, pre-authorizations vary by payer type and region. 

Providers should review payer-specific LCD documents on a quarterly basis since the criteria for the use of non-invasive liver disease assessment devices change frequently.

Claim Denial Reasons for CPT Code 91200

Claims submitted for CPT code 91200 are subject to several predictable denial patterns, each with a distinct remediation pathway.

Comparisons with Related CPT Codes

Understanding the boundaries of CPT code 91200 requires familiarity with adjacent elastography codes. Misapplication, particularly substituting 91200 for 76981, is a common audit finding.

CPT codes 91200 and 76981 are also considered mutually exclusive. If ultrasound imaging is done real-time with elastography, then CPT code 76981 should be reported and the CPT code 91200 will not be used. Payer audits often review claims where the CPT code 91200 is used and the procedure note states that concurrent imaging is performed.

CPT Code 0346T which was previously reported for vibration elastography (i.e., done without any imaging) has since been deleted and incorporated into 91200. All provider charge templates should be updated so that CPT Code 0346T does not appear on any active charge templates.

Conclusion

The CPT Code 91200 is important both clinically and financially because it allows for a non-invasive assessment of hepatic fibrosis in gastroenterology and hepatology practices. Correctly billing for CPT Code 91200 requires accurate reporting along four distinct dimensions: 1) Precise procedure identification (non-imaging VCTE); 2) Completeness of documentation (kPa, IQR/M, provider’s signature, non-imaging); 3) Accurate use of modifiers (global or component); and 4) Specification of the ICD-10 code (the qualifying chronic liver disease diagnoses).

If there were to be a gap in one of these four elements, it would result in an eventual denial of payment by the payer or underpayment, and would also create a practice that is vulnerable to audit.

Nexus io has an AAPC-certified billing team dedicated to providing gastroenterology billing services to help GI practices preserve revenue through all phases of the claim lifecycle, including FibroScan® charge entry and modifier validation, denial appeal management, and MAC LCD compliance. Nexus io provides the precision and turnaround requirements that high-volume practices can expect. You can learn more about Nexus io’s medical billing services or contact them today to benchmark your current CPT code 91200 claims performance and identify trends of underpayment.

Frequently Asked Questions

Is CPT code 91200 covered by Medicare? 

Medicare Part B will cover CPT code 91200; however, the claim must have both a valid ICD-10 code and sufficient documentation supporting the claim. Coverage criteria are established by the local coverage determination (LCD) of each Medicare Administrative Contractor (MAC). 

Therefore, providers are encouraged to check both the national Medicare Physician Fee Schedule (MPFS) and their jurisdiction-specific LCD to verify what they are currently covered for and what limitations apply to the frequency of those coverage decisions.

What ICD-10 codes support CPT code 91200? 

Major payers’ payment policies specify the qualifying ICD-10 diagnosis codes for CPT code 91200. Each MAC’s LCD also identifies these codes. The qualifying codes include B18.0, B18.1, B18.2, B18.8, and B18.9 for chronic viral hepatitis. 

Acute viral hepatitis diagnosis codes include B19.0, B19.1, and B19.2; and general liver disease can be coded with K70.0 to K77. Abnormal liver test results are covered by code R94.5. All services billed to CPT code 91200 must contain the highest level of ICD-10 specificity.

Can CPT code 91200 be billed on the same day as an E/M service? 

Yes, provided the E/M service is separately identifiable and not solely related to the elastography encounter. Modifier 25 must be appended to the E/M code to signal a distinct, significant service.

What is the key documentation difference between CPT 91200 and 76981? 

The use of CPT code 91200 will be determined by the presence or absence of simultaneous B-Mode imaging. If CPT code 91200 is used, documentation should clearly indicate that no imaging was utilized. 

Age-specific coding errors in pediatric billing cost healthcare practices significant revenue annually. According to the American Academy of Pediatrics, the average claim denial rate for pediatricians reaches 13%, substantially exceeding the healthcare industry’s overall denial rate of 5-10%. A considerable portion of denials stems from age-inappropriate code selection and inadequate documentation.

The Centers for Medicare & Medicaid Services enforces strict age-based coding requirements across pediatric CPT code categories. This guide examines the pediatric CPT codes list, organized by developmental age categories, for accurate billing.

Pediatric CPT Codes by Age Group: The Four Essential Categories

The American Medical Association structures the CPT code pediatric billing into four developmental age categories. The CPT code pediatric framework ensures accurate representation of physician work across developmental stages. Pediatric CPT code selection requires precise age verification on the date of service.

The Four Age Categories:

•  Infant (birth to under 1 year)
• Early Childhood (1-4 years)
• Late Childhood (5-11 years)
• Adolescent (12-17 years)

These categories apply across all CPT codes for pediatrics. Understanding CPT codes for pediatrics by age category prevents common billing errors.

Pediatric CPT Codes for Newborn Care Services

Hospital care for neonates utilizes specialized codes. The CPT code newborn exam structure differs from office-based care. Providers must understand both the CPT code pediatric newborn categories and office-visit codes.

The 99460 CPT code description covers initial hospital care for evaluation of a normal newborn infant. This CPT code newborn exam includes examination of vital signs and reflexes. Understanding the 99460 CPT code description prevents billing errors.

Pediatric CPT Codes for E/M Visits

Evaluation and management visits for sick children utilize standard E/M codes. The CPT code pediatric E/M structure applies uniformly across age groups. Proper selection from CPT codes for pediatrics E/M categories ensures accurate reimbursement.

Pediatric CPT Codes for Preventative Care

Office-based well-child visits follow the CPT code for pediatric well visit structure with distinct codes for each age category. The pediatric CPT codes list includes specific preventive codes. The selection of the appropriate CPT code for a pediatric well visit requires verification of patient age. The CPT code pediatric preventive care framework spans all four age categories.

Understanding CPT codes for pediatric preventive services ensures proper billing. Providers must distinguish between the CPT code for pediatric well visit office encounters, the CPT code newborn exam hospital services, and the CPT code for newborn well visit outpatient appointments.

The 99393 CPT code description encompasses comprehensive health supervision, including screening and counseling. The CPT code for newborn well visit schedule includes visits at 2, 4, 6, 9, and 12 months. Each CPT code for pediatric well visit incorporates age-appropriate developmental screening.

Pediatric CPT Codes for Immunization

Vaccine administration uses component-based coding for patients under 18 years. The CPT code pediatric immunization billing structure requires counting individual vaccine components. Accurate application of CPT codes for pediatric immunization services prevents underbilling.

Common Vaccine Products

Pediatric CPT Codes for Counseling, Preventive Medicine & Risk Reduction

Time-based counseling codes apply when provided separately from preventive visits.

Pediatric CPT Codes for Chronic Care Management

Chronic care management applies when patients have two or more chronic conditions. The CPT code pediatric chronic care structure supports ongoing management of complex conditions. Proper use of CPT codes for pediatric chronic care management generates additional revenue.

Pediatric CPT Codes for Principal Care Management

Principal Care Management addresses patients with one complex chronic condition. The CPT code pediatric principal care management structure fills the gap for single-condition patients. Understanding CPT codes for pediatric principal care management enables proper billing.

Prevent Revenue Loss with Expert Pediatric Billing Support

Age-transition errors at 18, incorrect vaccine component counts, and missed preventive service billing cost pediatric practices thousands monthly. These aren’t random mistakes—they’re systematic gaps that repeat until someone catches them.

Nexus io specializes in pediatric billing services built around age-based CPT requirements. Our certified coders know the difference between 99384 and 99385, understand three-component MMR billing, and catch well-child visit documentation gaps before claims leave your practice.

We provide eligibility verification, charge capture optimization, denial management, and compliance monitoring designed specifically for pediatric revenue cycles.

Our clients achieve clean claim rates exceeding 94% while reducing accounts receivable days and administrative burden. Ready to improve your pediatric billing accuracy? Schedule a free consultation to identify coding gaps costing your practice revenue.

According to the American Society of Anesthesiologists, improper coding accounts for nearly 25% of anesthesia claim denials, resulting in significant revenue loss for healthcare practices. The complexity of anesthesia CPT codes, combined with evolving documentation requirements, creates substantial challenges for billing specialists. Understanding proper anesthesia medical coding principles is essential for maximizing reimbursement while maintaining CMS and AMA compliance.

This guide provides healthcare professionals with a comprehensive anesthesia billing codes reference, covering code ranges, modifiers, and best practices for accurate claim submission.

Anesthesia CPT Codes Description

Anesthesia codes represent a specialized category within the Current Procedural Terminology system maintained by the American Medical Association. In contrast to other medical services, the CPT code for anesthesia incorporates multiple components that determine final reimbursement amounts.

Key Components of Anesthesia Medical Coding

Base Units

Each anesthesia procedure code has a predetermined base unit value established by the ASA to reflect procedural complexity. These units form the foundation for calculating total anesthesia time. 

Time Units

Anesthesia billing codes are billed in time increments of 15 minutes, beginning with the anesthesiologist’s preparation of the patient and ending with the transfer of care to recovery personnel.

Physical Status Modifiers

These modifiers (P1-P6) indicate patient health status and may affect reimbursement depending on payer policies, with some insurers adding additional unit values for higher-risk patients (P3-P6). 

Qualifying Circumstances

Specific CPT codes (99100, 99116, 99135, 99140) may be added when procedures involve emergency conditions, extreme age, controlled hypotension, or hypothermia requiring anesthesia services. 

Accurate selection of anesthesia codes requires precise documentation linking the anesthetic service to the corresponding surgical or diagnostic procedure performed.

Common Anesthesia CPT Codes by Anatomical Region

Anesthesia procedure codes are organized by anatomical location, facilitating systematic code selection based on surgical site. A strong understanding of these anesthesia code ranges ensures accurate billing for procedures across all body systems.

Frequently Used Diagnostic and Screening Codes

CPT Code 00520: Anesthesia for Closed Chest Procedures

CPT 00520 covers anesthesia services for closed chest procedures, including bronchoscopy. This code applies when airway management requires general endotracheal anesthesia for diagnostic visualization. Your documentation needs to support the medical necessity of an advanced airway 

CPT Code 00812: Anesthesia for Colonoscopy

Report CPT 00812 for anesthesia services during colonoscopy procedures. This represents one of the most commonly billed anesthesia codes in outpatient gastroenterology settings. Your documentation needs to demonstrate why monitored anesthesia care exceeded standard sedation protocols to establish medical necessity.

CPT Code 01922: Anesthesia for Non-Invasive Imaging 

Use CPT 01922 for anesthesia during non-invasive imaging procedures like MRI or CT scans. This code typically applies to pediatric patients or individuals with claustrophobia who require deeper sedation levels for procedure completion. Your documentation needs to justify the sedation depth required based on patient-specific factors preventing standard imaging protocols.

Specialized Anesthesia Procedure Codes

Complex surgical procedures require specialized anesthesia medical coding for accurate reimbursement.

CPT Code 00561: Anesthesia for Pediatric Cardiac Surgery with Pump Oxygenator 

CPT 00561 designates anesthesia services for heart surgery with a pump oxygenator in patients under one year of age. This code carries higher base units due to the increased complexity and risk associated with pediatric cardiac cases. 

CPT Code 00670: Anesthesia for Extensive Spine Procedures 

Report CPT 00670 for anesthesia during extensive spine procedures that typically require general endotracheal anesthesia for prolonged surgical times. This code applies to complex spinal surgeries, including multilevel fusion with instrumentation.

CPT Code 01996: Daily Management of Epidural or Subarachnoid Drug Administration 

CPT 01996 covers daily hospital management of continuous epidural or subarachnoid drug administration. This code applies to pain management cases extending beyond the initial procedure date. 

When procedures need general endotracheal anesthesia, clinical documentation must clearly indicate the rationale supporting this technique over regional anesthesia or monitored anesthesia care.

Critical Modifiers in Anesthesia Medical Coding

Accurate modifier application is essential for proper anesthesia billing codes submission and compliance with payer-specific requirements. Physical status modifiers communicate patient health status and directly impact how the CPT code for anesthesia is reimbursed:

Additional modifiers affect reimbursement calculations for anesthesia procedure codes:

Modifier 23: Indicates unusual anesthesia required due to extraordinary circumstances, such as extreme patient age, severe obesity, or emergency conditions that complicate anesthesia delivery.

Modifier AA: Specifies that an anesthesiologist personally performed the anesthesia service without medical direction.

Modifier QX: Designates a Certified Registered Nurse Anesthetist who provided services under physician direction, affecting reimbursement split for anesthesia codes.

Proper modifier application to anesthesia billing codes ensures accurate payment and reduces denial rates.

Time Reporting and Documentation Standards

Anesthesia procedure codes require precise time documentation in 15-minute increments. Time begins when the anesthesiologist starts patient preparation and ends when personal attendance is no longer required.

Critical documentation for anesthesia CPT codes must include:

• Pre-anesthesia evaluation documenting the patient’s history and physical status
• Intraoperative record with vital signs and medication times
• Documented anesthesia start/stop times
• Post-anesthesia assessment

Time-based billing for anesthesia medical coding differs substantially from other procedural coding, as reimbursement directly correlates with documented anesthesia duration rather than work relative value units alone.

Essential Guidelines for Accurate Anesthesia CPT Codes Selection

Match Surgical Procedures Precisely

The CPT code for anesthesia must match the exact surgical procedure performed. Before selecting anesthesia codes, review operative reports to ensure anatomical accuracy.

Apply Current Year Coding Updates

The American Medical Association issues annual CPT revisions. Outdated anesthesia billing codes lead to claim denials and compliance violations.

Document Medical Necessity Thoroughly

When procedures require the general endotracheal anesthesia CPT code rather than monitored care, documentation must support this with patient comorbidities or surgical complexity that affects anesthesia medical coding.

Verify Payer-Specific Policies

Insurance companies have different coverage policies for anesthesia procedure codes. Confirm preauthorization requirements to avoid denials of anesthesia billing codes.

Maintain Modifier Accuracy

Physical status modifiers affect reimbursement for the CPT code for anesthesia services. Assign modifiers based on documented conditions to ensure consistency with assigned anesthesia codes.

Conclusion

Getting anesthesia CPT codes right shouldn’t consume your administrative resources or cost you thousands. Yet many anesthesia practices struggle with time-based documentation errors, incorrect physical status modifiers, and preventable claim denials.

Nexus io provides specialized anesthesia billing services that accurately catch missing anesthesia start/stop times, unsupported general anesthesia selections that trigger audits, and incorrect modifier combinations (AA, QX, QZ) that lead to automatic rejections.

If your anesthesia billing denial rate exceeds 5%, you’re spending 10+ hours weekly on coding reviews, or you’re unsure whether you’re capturing all legitimate time units, contact Nexus io to schedule a complimentary practice analysis.