Surgical occlusion of middle meningeal artery in treatment of chronic subdural haematoma: anatomical and technical considerations.

BACKGROUND

The primary aim of chronic subdural haematoma (CSDH) treatment is to relieve pressure to improve neurological symptoms. The secondary aim is to avoid recurrence. The blood supply from the middle meningeal artery (MMA) to the haematoma membranes has recently become a research target, to enhance our understanding of the processes leading to growth and re-growth of a CSDH. Several studies indicate that endovascular embolization of the MMA (eMMA) reduces recurrence rates, but this effect must be confirmed in a randomized controlled setting. Endovascular embolization is an advanced and costly procedure carrying a significant risk of embolism in the elderly. The aim of this study was to assess anatomical and technical aspects of surgical occlusion of the MMA (soMMA) via a single same-procedure burr hole, as an alternative to eMMA.

METHOD

Technical aspects of soMMA were assessed using cadaver head dissection. MMA anatomy was examined by mapping the branching pattern and distribution of MMA in dry skulls, and CSDH position was investigated by analysis of computed tomography (CT) of CSDHs. Finally, we evaluated the possibility of CT-guided navigation to mark the branching point of the anterior MMA division on the skin.

RESULTS

We established anatomical landmarks to locate the MMA and found that particularly the anterior MMA branch can be occluded through a single burr hole at the pterion during the same procedure as haematoma decompression. CT of 1454 CSDHs in 1162 patients showed that the CSDH was anteriorly located in 57.5% compared with posteriorly in only 3%. This correlated with the anterior branch of the MMA being dominant in 58% of dry skull samples examined. We further confirmed that the MMA can be localized by neuronavigation as an alternative to using anatomical landmarks and average measurements.

CONCLUSION

A CSDH is mainly anteriorly located and supposedly primarily supplied by the anterior MMA branch. In a simulated setting, soMMA can be performed during the same procedure as haematoma decompression. A few reservations notwithstanding, we find that soMMA may be a viable alternative to eMMA in most CSDH cases and that soMMA should be further evaluated in a clinical setting.