Posterior petrous meningiomas: clinical manifestations, anatomical relationships and postoperative outcomes

BACKGROUND

Posterior petrous meningiomas (PPM) are located anterior and posterior to internal auditory meatus. Their relationships with cerebellopontine angle are variable, and they present with various symptoms.

OBJECTIVE

To create a classification of PPMs depending on location in relation to internal auditory meatus, and to compare clinical symptoms, anatomical relationships and postoperative outcomes for different groups of PPM.

MATERIAL AND METHODS

A retrospective study included 112 patients undergoing surgery for PPM (97 women and 15 men aged 25—80 years). There were 61 left-sided and 51 right-sided tumors (mean size 32.4 mm, range 10—66 mm).

RESULTS

PPMs were divided into retromeatal (R) in 44 cases, antemeatal (A) in 62 cases and anteretromeatal (AR) in 6 cases. PPM size in the R group was 34 mm (15—66 mm), in the A group — 30 mm (10—64 mm), in the AR group — 49 mm (38—65 mm). Total resection was performed in 84 patients (36, 47 and 1 in three groups, respectively). Anatomical integrity of cranial nerves was preserved in most patients. Postoperative deterioration of cranial nerve dysfunction was noted in 24 patients in groups A and AR.

CONCLUSION

Antemeatal meningiomas more often present with cranial nerve dysfunction, retromeatal meningiomas — with cerebellar symptoms. Retromastoid approach enables total/subtotal resection of PPM, and postoperative cranial nerve dysfunction is more common in antemeatal meningiomas. Preservation of anatomical and functional integrity of neurovascular structures is important for favorable postoperative outcomes.