Are codes 31295 and 31298 (Functional Endoscopic Sinus Surgery (FESS) and Balloon Sinuplasty) medically necessary for a patient with chronic maxillary sinusitis who has failed medical therapy and lacks a CT (Computed Tomography) report?

Medical Necessity Assessment for FESS (CPT 31295 and 31298)

No, codes 31295 and 31298 are NOT medically necessary at this time because a CT scan has not been obtained, which is an absolute prerequisite for surgical planning in chronic rhinosinusitis. 1

Critical Missing Requirement: CT Imaging

For any adult who is a candidate for sinus surgery, a computed tomography (CT) scan with a fine-cut protocol must be obtained to examine the paranasal sinuses for surgical planning. 1 This is a strong recommendation from the most recent 2025 American Academy of Otolaryngology guidelines and represents a non-negotiable requirement before proceeding with functional endoscopic sinus surgery. 1

• The absence of CT imaging makes it impossible to determine the extent of disease, identify anatomic variations, or plan which specific sinuses require surgical intervention. 1
• CT is considered mandatory for the safe performance of functional endoscopic sinus surgery, particularly when the ostiomeatal complex and ethmoids are involved. 1
• Standard radiographs are inadequate for surgical planning and cannot substitute for CT imaging. 1

Patient Does Meet Clinical Criteria for Surgical Candidacy

Despite the missing CT, this patient otherwise demonstrates appropriate candidacy for sinus surgery consideration:

Diagnostic Criteria Met

• Chronic rhinosinusitis diagnosis is confirmed: Symptoms present for 12+ weeks with multiple cardinal symptoms including nasal obstruction, facial pressure/pain, post-nasal discharge, and loss of smell. 1
• Positive validated outcome measures: SNOT-22 and ETDQ-7 scores document significant symptom burden and quality of life impact. 1

Failed Medical Management Documented

• Appropriate medical therapy trials completed: The patient has tried intranasal steroids, antihistamines, saline sinus rinses, and oral antibiotics (4+ courses within past year). 1
• Duration of medical therapy is adequate: Symptoms present for greater than 3 years with ongoing treatment attempts. 1
• The 2025 guidelines specifically state that surgeons should NOT require a predefined, one-size-fits-all regimen or duration of medical therapy as a prerequisite, and this patient has clearly exhausted reasonable medical options. 1

Quality of Life Impact

• Severe functional impairment: Unable to lay flat at night, constant mouth breathing, chronic pain from inspissated mucus, and ear symptoms affecting daily function. 1
• Long-standing disease: 32-year history since age 14 suggests chronicity and likelihood that medical management alone will be insufficient. 1

Required Next Step: Obtain CT Scan

Before any surgical authorization can be granted, a fine-cut CT scan of the paranasal sinuses must be obtained. 1 This imaging will:

• Confirm the presence and extent of sinus disease (maxillary, ethmoid, frontal, sphenoid involvement). 1
• Identify any anatomic variations that would affect surgical approach. 1
• Determine if disease characteristics warrant full functional endoscopic sinus surgery versus balloon sinuplasty alone. 1
• Rule out complications such as bony erosion, osteitis, or fungal disease that would require more extensive surgical intervention. 1

Surgical Approach Considerations Once CT Obtained

If CT Shows Polyps, Osteitis, or Extensive Disease

Full functional endoscopic sinus surgery (31295) would be indicated rather than balloon sinuplasty alone (31298). 1 The 2025 guidelines make a strong recommendation that when sinuses involve polyps, osteitis, bony erosion, or fungal disease, surgery must include full exposure of the sinus cavity and removal of diseased tissue, not just balloon or manual ostial dilation. 1

If CT Shows Isolated Ostial Obstruction Without Polyps

Balloon sinuplasty (31298) could be appropriate if imaging demonstrates isolated maxillary ostial obstruction without significant mucosal disease, polyps, or bony changes. 1

Common Pitfalls to Avoid

• Do not proceed with surgery based on symptoms alone without CT confirmation. Even with classic symptoms and failed medical therapy, CT is mandatory for surgical planning. 1
• Do not assume the extent of surgery based solely on the diagnosis of "chronic maxillary sinusitis." The surgeon should not plan the extent of sinus surgery solely based on arbitrary criteria regarding mucosal thickening or sinus opacification on CT. 1
• Do not deny surgery simply because more medical therapy could theoretically be tried. This patient has documented 3+ years of symptoms with multiple appropriate medical interventions, and the guidelines specifically reject requiring arbitrary durations of medical therapy. 1

Documentation Required for Authorization

Once CT is obtained, the following must be documented for surgical authorization:

• CT scan report confirming chronic rhinosinusitis with specific sinuses involved. 1
• Documentation that anticipated benefits of surgery exceed nonsurgical management alone. 1
• Patient counseling regarding realistic expectations, potential for chronicity or relapse, and likelihood of long-term medical management post-surgery. 1
• Specific surgical plan based on CT findings (which sinuses will be addressed and why). 1

Bottom line: Order the CT scan first. Once obtained, this patient will likely meet all criteria for surgical intervention, but the specific procedures authorized (31295 vs 31298 or both) will depend on the CT findings. 1