Objectives To review the utility of non-tumour brain biopsies in Alder Hey Children’s NHS Foundation Trust Paediatric Neurosurgery Department.

Methods Operative records were searched for ‘biopsy’. Case notes were reviewed for referral source, histology, surgical complication and outcome. Tumour, epilepsy and non-brain biopsy cases were excluded.

Results 83 ‘biopsy’ cases were identified between 2008 and 2017. 31 tumour, 5 epilepsy, 2 infections and 28 non brain/other biopsies were excluded. 17 brain biopsies for non-tumour causes were seen. 15 patients were referred by neurology, 2 by rheumatology. 14 underwent a craniotomy/mini-craniotomy, 3 had burrholes.4 biopsies were non diagnostic, 2 were abnormal but inconclusive for diagnosis. Diagnoses included: 3 demyelinating lesions, 2 normal brain tissue, 1 neurosarcoidosis, 1 autoimmune encephalitis, 1 definite Rasmussen’s Encephalitis, 1 possible Rasmussen’s Encephalitis, 1 systemic lupus erythematosus associated CNS vasculitis, 1 inflammatory infiltrate (secondary to hydrocephalus/ventriculitis), 1 patient developed a late wound infection. No other surgical morbidities/mortalities were recorded. 11 of these cases had a change in management or the treating team were reassured due to the result of the biopsy (i.e. were able to start immunomodulatory drugs in the absence of infection).

Conclusions 65% of brain biopsies were diagnostic. 71% of biopsies either changed management or reassured the treating team about a line of management. The procedure is low risk with 0.06% morbidity and 0% mortality.