Orbital reconstruction and volume in the correction of proptosis after resection of spheno-orbital meningiomas

J Neurosurg 140:1305–1311, 2024

The objective of this study was to evaluate the effect of reconstruction and orbital volume on the reduction of proptosis in patients undergoing resection for spheno-orbital meningiomas. Additionally, potential predictors of optimal proptosis reduction after surgery were evaluated.

METHODS Patients with spheno-orbital meningiomas who underwent resection at the authors’ institution between 2005 and 2020 were evaluated retrospectively. The exophthalmos index (EI) was measured on pre- and postoperative imaging to quantify proptosis and calculate the primary outcome measure of proptosis reduction. Patients were excluded if they had no preoperative proptosis (i.e., EI < 1.1), prior resection, or insufficient imaging available for analysis. Clinical and surgical characteristics were collected, including sex, extent of resection, WHO grade, and rigid orbital reconstruction, and assessed as predictors of greater proptosis reduction. Additionally, orbital volumes of the affected and contralateral orbits were measured to correlate postoperative orbital volumes with proptosis reduction.

RESULTS Thirty-three patients, with a mean age of 53 years, met inclusion criteria. The majority of the patients were female (23, 69.7%), and most tumors were classified as WHO grade 1 (29, 87.9%). Six patients (18.2%) underwent rigid orbital reconstruction. The mean EI across all patients decreased from 1.36 ± 0.18 to 1.19 ± 0.15 (p < 0.001). Patients who underwent reconstruction had on average a 76.4% greater reduction in the EI (p = 0.036) and a 9.1 times higher odds of achieving a normal EI (< 1.1) compared with those who did not receive reconstruction (OR 9.1, p = 0.025). Additionally, patients without residual hyperostotic bone compressing the orbit had a 2.16 times greater reduction in EI (p = 0.039). A linear relationship between orbital volume ratios (affected/unaffected orbit) and proptosis reduction was observed (p = 0.029, r = 0.529), including at ratios > 1.0. This suggests that greater orbital volumes postoperatively correlated with greater reductions in proptosis.

CONCLUSIONS Three factors were identified that optimize proptosis correction. First, all abnormal bone compressing the orbital contents must be removed completely. Second, rigid orbital reconstruction leads to improved proptosis correction, possibly by preventing frontal lobe and dural reconstruction from descending onto the compressed orbit. Third, aiming for an orbital volume slightly larger than the contralateral normal side leads to improved proptosis correction.

Hyperostosing sphenoid wing meningiomas: surgical outcomes and strategy for bone resection and multidisciplinary orbital reconstruction

J Neurosurg 134:711–720, 2021

Hyperostosing sphenoid wing meningiomas cause bony hyperostosis that may extend into the orbit, resulting in proptosis, restriction of extraocular movements, and/or compressive optic neuropathy. The extent of bony removal necessary and the optimal reconstruction strategy to prevent enophthalmos is debated. Herein, the authors present their surgical outcomes and reconstruction results.

METHODS This is a retrospective review of 54 consecutive patients undergoing resection of sphenoid wing meningiomas associated with bony hyperostosis. The majority of cases were operated on by the senior author. Extent of tumor resection, volumetric bone resection, radiographic exophthalmos index, complications, and recurrence were analyzed.

RESULTS The median age of the cohort was 52.1 years, with women comprising 83% of patients. Proptosis was a presenting symptom in 74%, and 52% had decreased visual acuity. The WHO grade was I (85%) or II (15%). The median follow-up was 2.6 years. On volumetric analysis, a median 86% of hyperostotic bone was resected. Gross-total resection of the intracranial tumor was achieved in 43% and the orbital tumor in 27%, and of all intracranial and orbital components in 20%. Orbital reconstruction was performed in 96% of patients. Postoperative vision was stable or improved in 98% of patients and diplopia improved in 89%. Postoperative complications occurred in 44% of patients, and 26% of patients underwent additional surgery for complication management. The most frequent complications were medical complications and extraocular movement deficits. The median preoperative exophthalmos index was 1.26, which improved to 1.12 immediately postoperatively and to 1.09 at the 6-month follow-up (p < 0.001). Postoperatively, 18 patients (33%) underwent adjuvant radiotherapy after subtotal resection. Tumors recurred/progressed in 12 patients (22%).

CONCLUSIONS Resection of hyperostosing sphenoid wing meningiomas, particularly achieving gross-total resection of hyperostotic bone with a good aesthetic result, is challenging and associated with notable medical and ocular morbidity. Recurrence rates in this series are higher than previously reported. Nevertheless, the authors were able to attain improvement in proptosis and visual symptoms in the majority of patients by using a multidisciplinary approach.