🎤 CPT 31535 — Laryngoscopy, Direct, Operative, With Biopsy (Without Operating Microscope or Telescope)
Quick Reference
wRVU: 3.08 | Global Period: 000 | Assistant Payable: Generally No (statutory restriction likely applies — verify current indicator) | Bilateral Indicator: 0 Rule: CPT 31535 carries a 000-day global period, so any E/M performed the same day is separately billable only with modifier -25 if significant and separately identifiable. Bilateral indicator “0” reflects that the larynx is a midline structure — the 150% bilateral payment adjustment does not apply. This code is distinct from 31536 (same biopsy procedure performed with an operating microscope or telescope), and the two are mutually exclusive on the same date of service for the same lesion.
📋 Clinical Description
CPT 31535 describes a direct operative laryngoscopy performed to biopsy a suspicious or symptomatic laryngeal lesion, without the aid of an operating microscope or telescope.¹ The surgeon inserts a rigid laryngoscope transorally under general anesthesia to directly visualize the glottis, supraglottis, and subglottis, then uses biopsy forceps to obtain tissue from an identified lesion for histopathologic analysis.³
This code sits within the direct-laryngoscopy family (31515–31579) and is most often differentiated from sibling codes by two variables: whether magnification was used, and whether the intervention was purely diagnostic (biopsy only) versus therapeutic (excision, injection, dilation). Compared to 31536, which reports the identical biopsy procedure but adds an operating microscope or telescope for enhanced visualization and carries a higher wRVU (3.46 vs. 3.08),⁴ 31535 is reserved for cases where magnification was not medically necessary or documented. Compared to 31540, which reports excision of tumor and/or stripping of the vocal cords with a 090-day global, 31535 is strictly a sampling procedure — if the operative note describes therapeutic removal of the entire lesion rather than a representative biopsy, 31540 or 31541 is the more accurate code.
This procedure may be performed in the following clinical contexts:
- Persistent hoarseness or dysphonia — Voice changes lasting more than 2–3 weeks, especially in patients with a smoking history, warrant direct visualization and tissue sampling to rule out malignancy.
- Suspected laryngeal malignancy on prior indirect or flexible exam — When office-based flexible laryngoscopy (e.g., 31575) identifies a suspicious lesion, direct laryngoscopy with biopsy is performed in the OR to obtain definitive tissue for staging.
- Evaluation of vocal cord lesions (nodules, polyps, leukoplakia) — Biopsy differentiates benign hyperplastic/inflammatory change from dysplasia or carcinoma in situ.
- Unexplained stridor or airway narrowing with a visualized mass — Direct laryngoscopy allows both airway assessment and tissue diagnosis in a single operative setting.
🔬 Anatomical & Procedural Considerations
| Variant | Mechanism | Key Notes |
|---|---|---|
| 31535 — Without microscope | Rigid laryngoscope is suspended or hand-held; the surgeon visualizes the lesion directly with the naked eye and takes forceps biopsies of the glottis, supraglottis, or subglottis. | Lower wRVU (3.08) than the microscope-assisted variant; appropriate when the lesion is grossly visible and magnification is not clinically required for accurate sampling. |
| 31536 — With operating microscope or telescope | Identical approach, but the laryngoscope is suspended and an operating microscope (or rigid telescope) is used for magnified, often binocular, visualization during biopsy. | Reflects higher work intensity; requires operative documentation specifically referencing microscope/telescope use to support the code, not just “suspension laryngoscopy.” |
| 31576 — Flexible laryngoscopy with biopsy | A flexible fiberoptic scope, rather than a rigid direct laryngoscope, is passed transnasally, often under topical/local anesthesia in an office setting. | Substantially lower wRVU (1.84); used when general anesthesia and rigid instrumentation are not required, typically for smaller or more accessible lesions. |
Clinical Pearl
The determining factor between 31535 and 31536 is documented use of magnification, not setting or anesthesia type — an operative note that says only “direct laryngoscopy under suspension with biopsy” and never mentions a microscope or telescope should default to 31535. Auditors frequently flag charts where 31536 was billed based on the surgeon’s habitual template language rather than what was actually documented for that specific case, so confirm the equipment used is explicitly stated before assigning the higher-valued code.
✅ Procedure Includes
- Suspension or direct visualization setup — Positioning and, if used, suspension of the laryngoscope to free the surgeon’s hands for instrumentation.
- Examination of the oral cavity, oropharynx, hypopharynx, larynx, and trachea — The direct laryngoscope traverses and allows inspection of all these structures as part of the approach.²
- Identification of the lesion(s) — Visual assessment of location, size, and characteristics of the abnormal tissue.
- Forceps biopsy of the lesion — Removal of a representative tissue sample for pathology.
- Hemostasis at the biopsy site — Control of any bleeding from the sampled area before scope withdrawal.
- Specimen handling and labeling for pathology submission — Preparation of the tissue sample for histopathologic evaluation.
❌ Excludes / Do Not Report Together
| Code | Description | Relationship |
|---|---|---|
| 31536 | Laryngoscopy, direct, operative, with biopsy; with operating microscope or telescope | Mutually exclusive with 31535 for the same encounter — the two differ only by magnification and cannot both be reported for a single biopsy episode. Select based on explicit operative documentation of microscope/telescope use, not surgeon habit. |
| 31540 | Laryngoscopy, direct, operative, with excision of tumor and/or stripping of vocal cords or epiglottis; without microscope | Represents therapeutic excision rather than diagnostic sampling; if the entire lesion is removed with therapeutic intent (not just a biopsy fragment), 31540 supersedes 31535 and carries a 090-day global rather than 000. |
| 31525 | Laryngoscopy, direct, with or without tracheoscopy; diagnostic, except newborn | A purely diagnostic (non-biopsy) direct laryngoscopy is bundled into 31535 when a biopsy is subsequently performed at the same session — the diagnostic scope is not separately reportable. |
| 31500 | Laryngoscopy, direct, emergency, with or without tracheal intubation | Not bundled with 31535; if an emergency airway laryngoscopy is medically necessary and distinct from a planned operative biopsy at the same encounter, both may be reported with appropriate modifiers and documentation. |
Bundling Alert
Because 31535 carries a 000-day global period, all pre- and post-procedure E/M services on the same date require modifier -25 on the E/M to be separately payable, and any unrelated procedure performed by the same surgeon in the 0-day postoperative window needs modifier -79 rather than assuming automatic separate payment. The MUE for this code is 1 unit per date of service regardless of how many biopsies or laryngeal sites were sampled, so audit risk is highest when coders attempt to report multiple units or append modifier -51 for multiple biopsy sites within the same larynx — CMS and most commercial payers treat multi-site laryngeal biopsy as a single 31535 encounter.
🌳 Code Tree — Surgery: Endoscopy Procedures on the Larynx
CPT 31515-31579 Surgery: Larynx — Endoscopy Procedures
│
├── 31515-31520 Direct Diagnostic Laryngoscopy
│ ├── 31515 Laryngoscopy, direct, with or without tracheoscopy; for aspiration
│ └── 31520 Laryngoscopy, direct, with or without tracheoscopy; diagnostic, newborn
│
├── 31525-31541 Direct Operative Laryngoscopy (Foreign Body, Biopsy, Excision)
│ ├── 31525 Laryngoscopy, direct, with or without tracheoscopy; diagnostic, except newborn
│ ├── 31530 Laryngoscopy, direct, operative, with foreign body removal; without operating microscope (Global: 000)
│ ├── ▶▶ 31535 ◀◀ Laryngoscopy, direct, operative, with biopsy; without operating microscope or telescope ← YOU ARE HERE (Global: 000)
│ ├── 31536 Laryngoscopy, direct, operative, with biopsy; with operating microscope or telescope (Global: 000)
│ └── 31540 Laryngoscopy, direct, operative, with excision of tumor and/or stripping of vocal cords or epiglottis; without operating microscope (Global: 090)
│
├── 31541 Laryngoscopy, direct, operative, with excision of tumor and/or stripping of vocal cords or epiglottis; with operating microscope or telescope (Global: 090)
│
└── 31560-31579 Direct Laryngoscopy with Arytenoidectomy, Injection, or Stroboscopy
├── 31560 Laryngoscopy, direct, operative, with arytenoidectomy; without operating microscope
└── 31579 Laryngoscopy, flexible or rigid telescopic, with stroboscopy💰 RVU & Reimbursement Profile
| Component | Value |
|---|---|
| Work RVU | 3.08 (CMS PFS RVU26A, 2026)⁴ |
| Global Period | 000 — no pre/postoperative global days |
| Bilateral Indicator | 0 — bilateral payment concept does not apply (larynx is a midline structure) |
| Assistant Surgeon | Likely restricted (indicator 1 pattern for low-complexity single-scope biopsy codes) — verify current CMS PFS indicator before billing an assistant |
| Co‑Surgeon | Not typically supported — single-surgeon procedure; verify against current PFS if two-specialty involvement is documented |
| Team Surgery | Not applicable — not a team-surgery-eligible code |
| PC/TC Split | 0 — physician service code; PC/TC concept does not apply, modifiers -26 and -TC are not used |
| Modifier -51 Exempt | No — standard multiple-procedure reduction rules apply when billed with other same-session procedures |
| Anesthesia | Typically general anesthesia; base unit determined by the anesthesia CPT crosswalk (e.g., 00320/00326 family), not by 31535 itself |
Bilateral Billing Rules
The larynx is a single midline structure, so modifier -50 and laterality modifiers -RT/-LT are not applicable to 31535 regardless of whether the lesion is unilateral or bilateral on the vocal cords. Do not attempt to bill two units or append -50 to reflect bilateral vocal cord involvement — this is a single-organ, single-unit code per encounter.
🏷️ Modifier Reference
| Modifier | Name | When to Apply |
|---|---|---|
| -22 | Increased Procedural Services | Appropriate when significantly more time or difficulty was required (e.g., extensive scarring, difficult airway access) — must be supported by comparative operative time and a clear narrative in the op note. |
| -25 | Significant, Separately Identifiable E/M | Use when a significant, separately identifiable E/M service is performed by the same physician on the same date as 31535, distinct from the routine pre-procedure assessment. |
| -51 | Multiple Procedures | Applies when 31535 is reported with other significant procedures at the same session (not for multiple biopsy sites within the larynx itself, which remain a single unit). |
| -52 | Reduced Services | Use if the biopsy was attempted but performed at a reduced scope relative to what was planned, without full termination of the procedure. |
| -53 | Discontinued Procedure | Applies when the procedure is started but terminated due to extenuating circumstances (e.g., patient instability) before completion. |
| -58 | Staged or Related Procedure During Postop Period | Use if a planned staged procedure follows 31535 within the global period and is related to the original biopsy findings. |
| -59 | Distinct Procedural Service | Applies when 31535 is performed at a separate session, site, or lesion distinct from another same-day procedure that would otherwise be considered bundled. |
| -78 | Unplanned Return to OR | Use if the patient returns to the OR for a related procedure (e.g., bleeding control) during the 000-day global window. |
| -79 | Unrelated Procedure by Same Physician | Use if the same surgeon performs an unrelated procedure during the (brief) global period. |
🩺 Common ICD‑10‑CM Pairings
Primary Diagnosis Group
| ICD‑10 | Description | HCC? | Notes |
|---|---|---|---|
| C32.0 | Malignant neoplasm of glottis | ✅ Yes | Primary glottic cancer; direct laryngoscopy with biopsy is the definitive diagnostic step confirming this diagnosis before staging and treatment planning. |
| C32.1 | Malignant neoplasm of supraglottis | ✅ Yes | Supraglottic tumors often present later due to a more silent clinical course; biopsy confirms histology and guides whether primary surgery or chemoradiation is pursued. |
| C32.2 | Malignant neoplasm of subglottis | ✅ Yes | Subglottic lesions are less common and carry distinct staging/nodal drainage considerations; documentation should specify subglottic location precisely. |
| C32.9 | Malignant neoplasm of larynx, unspecified | ✅ Yes | Use only when the operative and pathology documentation do not specify the laryngeal subsite — specificity to C32.0/C32.1/C32.2 is preferred whenever the chart supports it. |
| D02.0 | Carcinoma in situ of larynx | ❌ No | Reported when pathology confirms in situ disease without invasion; distinct clinical and reimbursement pathway from invasive C32.x codes. |
Secondary Group
| ICD‑10 | Description | HCC? | Notes |
|---|---|---|---|
| D14.1 | Benign neoplasm of larynx | ❌ No | Used when biopsy confirms a benign process (e.g., papilloma, benign polyp with atypia ruled out). |
| J38.1 | Polyp of vocal cord and larynx | ❌ No | Common indication for biopsy when a polypoid lesion’s benign vs. dysplastic nature is uncertain on visual exam alone. |
Etiology / Complication
| ICD‑10 | Description | HCC? | Notes |
|---|---|---|---|
| R49.0 | Dysphonia | ❌ No | Appropriate presenting-symptom code when biopsy is performed for persistent voice change prior to a confirmed diagnosis. |
| J38.00 | Paralysis of vocal cords and larynx, unspecified | ❌ No | Relevant when biopsy is performed to rule out a mass lesion causing cord immobility; specify unilateral laterality codes (J38.01/J38.02) when documented. |
Coding Specificity Reminder
Always code to the highest specificity supported by the pathology and operative report — use laterality-specific vocal cord paralysis codes (J38.01 right, J38.02 left) rather than J38.00 whenever the chart documents which side is affected, and prefer subsite-specific malignancy codes (C32.0/C32.1/C32.2) over C32.9 whenever the operative note and pathology report identify the exact laryngeal subsite involved.
🏥 MS‑DRG Considerations
When 31535 is performed during an inpatient admission, it crosswalks to ICD-10-PCS 0CBS8ZX (Excision of Larynx, Via Natural or Artificial Opening Endoscopic, Diagnostic) and is classified as an O.R. procedure under MDC 03 (Diseases and Disorders of the Ear, Nose, Mouth, and Throat), typically grouping to MS-DRGs 129–131 (Major Head and Neck Procedures) when the laryngeal biopsy is the principal or only significant procedure of the stay; final DRG assignment, however, depends on the admitting/principal diagnosis, any CC/MCC secondary diagnoses captured, and whether additional procedures (e.g., tracheostomy, panendoscopy) were performed on the same admission. No national coverage determination (NCD) specifically addresses direct laryngoscopy with biopsy, and a search of current Noridian JE/JF local coverage did not return a laryngoscopy-specific LCD as of this review — coverage is instead governed by general medical-necessity documentation standards under the Medicare Benefit Policy Manual, so confirm there is no newly published Noridian LCD/Article for endoscopic laryngeal procedures before finalizing high-dollar or Medicare Advantage claims.⁵
🔧 ICD‑10‑PCS Equivalents
| PCS Code | Full Description | Modality |
|---|---|---|
| 0CBS8ZX | Excision of Larynx, Via Natural or Artificial Opening Endoscopic, Diagnostic | Endoscopic — matches the standard transoral direct laryngoscopy approach described by 31535. |
| 0CBS7ZX | Excision of Larynx, Via Natural or Artificial Opening, Diagnostic | Non-endoscopic natural-opening approach; rarely applicable to 31535 but included for completeness if documentation lacks endoscopic-specific language. |
| 0CBS0ZX | Excision of Larynx, Open Approach, Diagnostic | Open surgical approach; would apply only if an external/open laryngeal biopsy approach was documented rather than the standard transoral technique. |
| 0CBS4ZX | Excision of Larynx, Percutaneous Endoscopic Approach, Diagnostic | Percutaneous endoscopic approach; not the typical technique for 31535 but relevant if a percutaneous tracheal/laryngeal access route was used. |
PCS Character Analysis
| Position | Character | Value | Definition |
|---|---|---|---|
| 1 | Section | 0 | Medical and Surgical section — covers the vast majority of operative procedures including laryngeal excision/biopsy. |
| 2 | Body System | C | Mouth and Throat — the ICD-10-PCS body system that contains the larynx as a defined body part. |
| 3 | Root Operation | B | Excision — cutting out or off a portion of a body part without replacement, the correct root operation for a biopsy sample. |
| 4 | Body Part | S | Larynx — the specific body part value corresponding to CPT 31535’s target structure. |
| 5 | Approach | 8 | Via Natural or Artificial Opening Endoscopic — reflects the transoral, scope-assisted access used in direct laryngoscopy. |
| 6 | Device | Z | No Device — no implant, graft, or device is left in place during a diagnostic biopsy. |
| 7 | Qualifier | X | Diagnostic — indicates the excision was performed for diagnostic sampling rather than therapeutic removal. |
Root Operation Comparison
- Excision (B) vs. Resection (T): Excision is used for 31535 because only a portion of the lesion/tissue is removed for diagnosis; Resection (all of a body part) would apply instead to a total laryngectomy, not a biopsy.
- Excision (B) vs. Drainage (9): Drainage applies to removing fluids/gases, not solid tissue — a laryngeal biopsy is always coded as Excision, never Drainage, even though both can share the same endoscopic approach value.
- Diagnostic qualifier (X) vs. no qualifier: The “X” qualifier is essential — omitting it (0CBS8ZZ) would misrepresent a diagnostic biopsy as a therapeutic excision, which can distort MS-DRG grouping and procedure-volume reporting.
📝 Coding Examples
Example 1
Clinical Scenario: A 58-year-old male smoker presents with 6 weeks of progressive hoarseness. Office flexible laryngoscopy revealed an exophytic lesion on the right true vocal cord. He is taken to the OR for direct laryngoscopy with biopsy under general anesthesia; the surgeon documents direct visualization without use of a microscope or telescope, and forceps biopsy of the right vocal cord lesion is obtained. Pathology later confirms squamous cell carcinoma.
| Field | Code | Rationale |
|---|---|---|
| CPT | 31535 | Direct operative laryngoscopy with biopsy, explicitly documented without microscope/telescope use. |
| PDx | C32.0 | Biopsy-confirmed malignancy of the glottis (true vocal cord). |
Note
Example 2
Clinical Scenario: A 45-year-old female with chronic hoarseness undergoes direct laryngoscopy in the OR. The surgeon performs a biopsy of a vocal cord polyp without microscope use, and separately removes a small aspirated foreign body fragment noted incidentally in the subglottis during the same session, using distinct instrumentation and technique.
| Field | Code | Rationale |
|---|---|---|
| CPT 1 | 31535 | Direct laryngoscopy with biopsy of the vocal cord polyp, without microscope. |
| CPT 2 | 31530--59 | Foreign body removal represents a distinct procedural service performed on a separate structure (subglottis) during the same session. |
| PDx | J38.1 | Polyp of vocal cord as the primary indication for the biopsy portion of the encounter. |
Warning
Modifier -59 must be supported by clear operative documentation that the foreign body removal was a distinct, separately identifiable service and not an integral part of the biopsy procedure — payers frequently deny this combination without explicit narrative separation.
Example 3
Clinical Scenario: A 62-year-old male with known laryngeal papillomatosis returns for surveillance direct laryngoscopy. The surgeon biopsies a new area of thickened mucosa without microscope assistance to rule out malignant transformation; pathology confirms benign recurrent respiratory papillomatosis without dysplasia.
| Field | Code | Rationale |
|---|---|---|
| CPT | 31535 | Direct operative laryngoscopy with biopsy performed without magnification. |
| PDx | D14.1 | Benign neoplasm of the larynx, consistent with confirmed benign papillomatosis pathology. |
Global period reminder, if applicable
CPT 31535 carries a 000-day global period, so this surveillance encounter does not create any postoperative global restriction affecting future biopsy sessions or unrelated E/M visits.
⚠️ Common Coding Pitfalls
- Pitfall 1: Defaulting to 31536 because the surgeon’s template language always mentions “suspension laryngoscopy” — suspension refers to instrument setup, not magnification; only explicit documentation of a microscope or telescope justifies 31536 over 31535.
- Pitfall 2: Billing multiple units of 31535 for biopsies taken from more than one laryngeal subsite in the same session — the MUE is 1, and multi-site biopsy within a single laryngeal encounter is captured as one unit regardless of how many samples were obtained.
- Pitfall 3: Appending modifier -50 or laterality modifiers to reflect bilateral vocal cord involvement — the larynx is a single midline structure, and CMS’s bilateral indicator of 0 confirms this adjustment does not apply.
- Pitfall 4: Upcoding to 31540 when the operative note describes a biopsy that happened to remove the entirety of a small lesion — the distinguishing factor is documented surgical intent (diagnostic sampling vs. therapeutic excision), not incidental completeness of removal.
- Pitfall 5: Failing to append modifier -25 to a same-day E/M visit that meets separate-identifiability criteria, resulting in denied or bundled E/M payment despite a 000-day global period technically allowing it.
- Pitfall 6: Assigning C32.9 (unspecified larynx malignancy) by default when the operative report and pathology clearly document a specific subsite — this under-specifies the diagnosis and can affect both clinical registries and DRG/HCC accuracy.
📎 Sources
1. American Medical Association. *CPT® 2026 Professional Edition.* AMA Press; 2026. 2. AAPC. *CPT® Code 31535 — Endoscopy Procedures on the Larynx.* Codify by AAPC; 2026. https://www.aapc.com/codes/cpt-codes/31535 3. AAPC. *Recognize Key Words to Bill Effectively for Laryngoscopy Procedures.* My Otolaryngology Coding Alert; 2026. https://www.aapc.com/codes/coding-newsletters/my-otolaryngology-coding-alert/recognize-key-words-to-bill-effectively-for-laryngoscopy-procedures-article 4. RVU Edge. *CPT 31535 — Laryngoscopy with Biopsy, wRVU 3.08.* Data sourced from CMS Physician Fee Schedule RVU26A; 2026. https://rvuedge.com/cpt-codes/surgery/31535/ 5. Noridian Healthcare Solutions. *LCD/Article Search — Larynx/Endoscopy Procedures, JE/JF Jurisdictions.* CMS Medicare Coverage Database; accessed 2026.Sources listed above correspond to superscript citations throughout this note. Verify all Medicare payment figures against your current CMS PFS Lookup tool and applicable MAC LCD prior to claim submission. Please use the latest AAPC/AHIMA Coding Books to verify each code within this note.