# Surgical management of petrous apex lesions: a descriptive analysis of outcomes by anatomical location for the Kawase, retrosigmoid, and pterional approaches

## TL;DR

This study analyzes surgical outcomes for petrous apex lesions based on anatomical location and approach, showing that specific approaches yield predictable results and risks.

## Contribution

The study introduces a framework for surgical decision-making based on lesion anatomical location and approach-specific outcomes.

## Key findings

- The Kawase approach achieved 100% gross total resection for anteromedial lesions but had longer operative time and higher infection risk.
- The endoscope-assisted retrosigmoid approach provided good exposure with minimal trauma for posterior lesions.
- The pterional approach for superoanterior lesions was linked to higher cranial nerve dysfunction and speech impairment rates.

## Abstract

This study is a descriptive analysis that systematically delineates the perioperative outcome profiles of Kawase, endoscope-assisted retrosigmoid, and pterional approaches for resecting petrous apex lesions within the clinical decision-making framework of “anatomical location first.” A retrospective series of 27 patients was included. Based on the core anatomical location of the lesion, surgery was performed via the Kawase approach (anteromedial region, n = 14), the endoscope-assisted retrosigmoid approach (posterior region, n = 7), or the pterional approach (superoanterior region, n = 6). The results demonstrate that surgical approaches corresponding to different anatomical subregions exhibited characteristic outcome profiles. For anteromedial petrous apex lesions, the Kawase approach achieved a high gross total resection rate (100%), but was associated with longer operative time and a higher risk of postoperative intracranial infection. For posterior lesions, the endoscope-assisted retrosigmoid approach provided excellent exposure with minimal tissue trauma and a relatively balanced complication spectrum. For superoanterior lesions, the pterional approach, while allowing direct access, was associated with higher rates of postoperative cranial nerve dysfunction (trigeminal nerve injury 50%, facial nerve palsy 67%) and speech impairment (50%). In a subgroup analysis focusing on the predominant pathology (meningioma, n = 20), these outcome differences linked to specific anatomical location-approach pairings persisted. The findings indicate that surgical outcomes for petrous apex lesions are closely associated with the approach dictated by their anatomical location, presenting a predictable characteristic profile. Therefore, clinical decision-making should prioritize the precise anatomical location of the lesion when selecting the surgical approach, and fully acknowledge the inherent perioperative risk profile specific to each “anatomical region–surgical approach” pairing. The integration of ancillary techniques such as neuroendoscopy with classic approaches holds promise for further optimizing outcomes in complex cases. This study is a single-center, retrospective, descriptive analysis with a limited sample size; its conclusions require validation by prospective, large-sample studies.