Utility of PMMA-Based Cranioplasty Flap for the Reconstruction of Retromastoid Craniotomy Using a Single Standard Skull Model: A Low-Cost Alternative

Abstract

Introduction

Retrosigmoid suboccipital (RMSO) craniotomy is the most commonly used approach for lesions of cerebellopontine angle. The problem with RMSO craniotomy is the risk of injury to the transverse and sigmoid sinus during the fashioning of the craniotomy. This problem creates a craniectomy defect that is larger than the bone flap removed. Placement of such a bone flap would cause problems that are similar to the craniectomy defects. To avoid this complication, cranioplasty reconstruction is advised.

Objectives

In this study, we introduced a novel, low-cost technique for RMSO cranioplasty using a single standard polyvinyl chloride plastic skull model as a guide for cranioplasty flap development and observed the functional and cosmetic outcomes.

Results

None of the patients required reoperation, and there was no evidence of cerebrospinal fluid (CSF) leak, bleeding, infection, or poor scar formation. No patient experienced undue incisional pain or headache at long-term follow-up. The patients and their family members were satisfied with the cosmetic results of the procedure.

Conclusion

This technique has been proven to be not only cost-effective but also time-saving and easily reproduced, which may be significantly relevant in countries such as India, where the financial burden of healthcare is very high. This study identifies long-term improvement in CSF leaks and the long-term advantage of polymethylmethacrylate closure with less postoperative incisional pain and headache and improvement retroauricular cosmesis.

Keywords

RMSO craniotomy - cranioplasty - cerebellopontine angle - PMMA cranioplasty - custom made implant - craniotomy defect

Publikationsverlauf

Artikel online veröffentlicht:
26. Juni 2025

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