Summary & Overview
CPT 31290: Endoscopic Repair of CSF Leak in Ethmoid Sinus
CPT code 31290 denotes endoscopic repair of a cerebrospinal fluid (CSF) leak in the ethmoid sinus via a transnasal approach. The code captures a specialized otolaryngology/neurosurgical procedure that mitigates risks of meningitis and other intracranial complications by closing a communicating defect between the sinonasal cavity and the cranial vault. Nationally, this code represents an important procedural category as endoscopic skull base techniques have become standard for many CSF leak repairs, influencing facility resource use, surgical subspecialty staffing, and perioperative care pathways.
Key payers included in this analysis are Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of the clinical context for 31290, expected sites of service, common modifiers, and payer inclusion. The publication outlines national benchmarks where available, notes policy and coverage considerations relevant to facility and physician billing, and summarizes coding nuances that affect claim adjudication and reimbursement workflows.
This material is intended to provide a clear, national-level briefing on clinical purpose and billing context for CPT code 31290, equipping coding, billing, and policy teams with the background needed to interpret charges and guide further payer-specific inquiries.
Billing Code Overview
CPT code 31290 describes endoscopic repair of a cerebrospinal fluid (CSF) leak in the ethmoid sinus. In this procedure, the provider inserts an endoscope through the nasal cavity and repairs the CSF leak, for example by using a muscle tissue graft.
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Service type: Endoscopic skull base / intranasal surgical repair
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Typical site of service: Hospital outpatient department or ambulatory surgery center (endoscopic nasal cavity/skull base surgery)
Data not available in the input for associated taxonomies, ICD-10 diagnoses, and related codes.
Clinical & Coding Specifications
Clinical Context
A typical patient is a 45-year-old adult presenting with clear unilateral nasal drainage that increases with leaning forward, positional headaches, and a recent history of prior endoscopic sinus surgery or skull base trauma. Evaluation includes nasal endoscopy and high-resolution CT of the sinuses and skull base, often accompanied by beta-2 transferrin testing of the fluid to confirm cerebrospinal fluid (CSF). After localization of a defect in the ethmoid sinus roof or cribriform plate, the patient is scheduled for an endoscopic transnasal repair under general anesthesia. The surgical workflow includes intraoperative endoscopic visualization (nasal endoscopy), identification of the CSF leak site, preparation of local mucosa, and repair using grafts (e.g., autologous fascia, muscle, fat) or vascularized flaps. Intraoperative measures include lumbar drainage or intrathecal fluorescein in selected cases for leak localization, and hemostasis measures. Postoperative care includes nasal packing or splints, activity restrictions to avoid Valsalva, prophylactic antibiotics as indicated, and follow-up endoscopic surveillance to confirm healing and absence of recurrent leak or meningitis. Typical site of service is an ambulatory surgical center or hospital operating room. Service type is surgical, specifically endoscopic skull base/ENT surgical repair of CSF leak using intranasal endoscopy.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
22 | Increased procedural services |