580 A Surgical Dilemma; Complicated Case of Dandy Walker Malformation

Case summary

A 24-year-old male presented to the department with a 1-week history of sudden onset posterior headache and multiple episodes of vomiting. He reported similar episodes 8 months prior with ataxia which resolved itself. He has a past medical history of dandy walker malformation (DWM) diagnosed in early infancy and a shunt inserted at 3 months old due to hydrocephalus.

Initial blood investigations revealed extremely low platelets, low TLC and markedly raised potassium along with splenomegaly. Neurological examination was unremarkable with GCS of E4V5M6. A CT scan revealed hydrocephalus requiring revision shunt surgery. However, surgery was avoided due to the risks associated with thrombocytopenia therefore multiple specialists were consulted before a final decision could be reached.

Discussion

DWM is a rare congenital malformation typically presenting in early childhood characterised by hypoplasia of the cerebellar vermis, posterior fossa dilation and cystic enlargement of 4th ventricle. A complication of DWM is hydrocephalus, which requires surgery to correct via shunt insertion. However, this patients’ haematological instabilities risks deterioration and even death during surgery as preoperative thrombocytopenia has been associated with increased intra- and post-operative mortality. As such the patient was not advised surgery initially however the hydrocephalus was causing severe headaches to the patient ultimately making it difficult for surgeons to decide when surgery should be performed. On follow up, the patient was discharged with no shunt revision due to resolution of symptoms. This case highlighted the need for skilled physicians across multiple specialities to make a shared decision about surgical or conservative management.