# Size of decompressive craniectomy as prognostic factor in space-occupying ischemic cerebellar stroke –a multicentric retrospective study

## TL;DR

This study finds that larger decompressive craniectomy in cerebellar strokes is linked to better recovery outcomes.

## Contribution

The study identifies a lateral diameter threshold of ≥6.5 cm for improved functional outcomes in cerebellar stroke surgery.

## Key findings

- A lateral diameter of ≥6.5 cm in craniectomy is associated with better 3-month functional outcomes.
- No significant difference in mortality was found between larger and smaller craniectomies.
- The study is the largest multicenter analysis of craniectomy size in cerebellar ischemic stroke.

## Abstract

In cases of space-occupying cerebellar ischemic strokes, guidelines recommend suboccipital decompressive surgery (SDC). While in supratentorial hemispheric stroke, the size of the bone flap has been the subject of many studies and ample debate, no studies have been conducted to determine the optimal size of the bone flap to be removed in SDC.

To determine the optimal size of SDC in ischemic cerebellar stroke.

This is a multicentric retrospective study of patients undergoing SDC for ischemic cerebellar stroke. SDC size was determined in two perpendicular planes on early postoperative CT scans: (a) maximal lateral extension (L) and (b) maximal craniocaudal extension (CC) in cm. The primary endpoint was functional outcome according to modified Rankin Scale (mRS) at three months. Secondary outcome was mortality at three months, as well as surgical complications.

A total of 88 patients were included in the final analysis. The mean L diameter of the SDC analyzed was 7 cm (SD 1.5), whereas the mean CC diameter was 4.4 cm (SD .8). When dichotomizing patients based on a threshold of L ≥ 6.5 cm, favorable outcome was more likely in the group with L ≥ 6.5 cm (OR = 3.23, 95%CI 1.02–10.56, p = .045). No statistically significant differences were observed in mortality at three months (OR = .66, 95%CI .24–1.78, p = .40).

In ischemic cerebellar stroke, a suboccipital craniectomy with a maximum lateral diameter of ≥6.5 cm appears to yield better functional outcomes than smaller ones. Prospective studies are needed to confirm these results.

•Largest multicenter study on craniectomy size in cerebellar ischemic stroke.•Lateral diameter ≥6.5 cm linked to better 3-month functional outcomes.•Suggests decompression of ∼50 % cerebellar convexity for optimal results.

Largest multicenter study on craniectomy size in cerebellar ischemic stroke.

Lateral diameter ≥6.5 cm linked to better 3-month functional outcomes.

Suggests decompression of ∼50 % cerebellar convexity for optimal results.