A case of spontaneous haematoma from vertebral artery arterio-venous fistula in a patient with neurofibromatosis type 1.

Neurofibromatosis type 1 (NF1) is an autosomal dominant condition caused by a mutation on chromosome 17. Vascular abnormalities are recognised complications of NF1. These include aneurysms, stenoses, arteriovenous malformations, fistulae, etc. We report the case of a young gentleman with NF1 with a spontaneous cervical bleed from an arteriovenous fistula arising from the left vertebral artery, and illustrate the various management options and difficulties arising from rapid fistula formation.

A phantom-based evaluation of three commercially available patient organ shields for computed tomography X-ray examinations in diagnostic radiology.

Three commercially available in-plane patient organ shields (barium eye, bismuth eye and bismuth breast) for computed tomography (CT) examinations were evaluated to determine their effectiveness for dose reduction. Absorbed doses were measured using metal oxide semiconductor field effect transistor dosemeters fastened to a Kyoto CT Torso phantom. Resultant images were visually compared with those minus shielding by an experienced radiologist. Approximate dose reductions of 21, 38 and 50 % were achieved by the barium eye, bismuth eye and bismuth breast shields, respectively, at a cost of increased image noise and streak artefacts. Shielded images produced varied levels of image artefact, particularly those resulting from the eye shields. Measured dose reductions were not consistent with the potential dose savings stated by the manufacturers of the shields. When evaluating the breast shield, similar dose reduction was achieved without shield-induced artefact by simply reducing the X-ray tube current.

Progressive seizures in a patient with congenital coagulopathies.

Dural arteriovenous fistula (DAVF) is a rare complication of cerebral venous sinus thrombosis (CVST). DAVFs develop as a result of direct arterial to venous sinus communications evolving in response to an occluded sinus. The authors present a patient with Down's syndrome who developed progressive, uncontrolled seizures and chronic CVST secondary to factor V Leiden deficiency. Brain MRI and computerised tomographic venography revealed a complex secondary DAVF, which once embolised resulted in a dramatic reduction in seizures and improvement in the clinical state. DAVFs should be considered as a potential complication in patients with persistent features of CVST.

Persistent CSF Rhinorrhoea, Pneumocephalus, and Recurrent Meningitis Following Misdiagnosis of Olfactory Neuroblastoma.

A 41-year-old female patient was admitted with streptococcal meningitis on a background of 5-month history of CSF rhinorrhoea. Imaging revealed an extensive skull base lesion involving the sphenoid and ethmoid sinuses, the pituitary fossa with suprasellar extension and bony destruction. Histological examination of an endonasal transethmoidal biopsy suggested a diagnosis of olfactory neuroblastoma. A profuse CSF leak occurred and the patient developed coliform meningitis. A second endonasal endoscopic biopsy was undertaken which demonstrated the tumour to be a prolactinoma. Following endonasal repair of the CSF leak and lumbar drainage, she developed profound pneumocephalus. The patient underwent three further unsuccessful CSF leak repairs. Definitive control of the CSF leak was finally achieved through a transcranial approach with prolonged lumbar drainage. This case illustrates some of the potentially devastating complications which can occur as a consequence of complex skull base lesions. A multidisciplinary approach may be required to successfully manage such cases.