Aneurysmal subarachnoid haemorrhage: guidance in making the correct diagnosis.

BACKGROUND: The natural history of untreated aneurysmal subarachnoid haemorrhage carries a dismal prognosis. Case fatalities range between 32% and 67%. Treatment with either surgical clipping or endovascular coiling is highly successful at preventing re-bleeding and yet the diagnosis is still missed. METHODS: Based on the national guidelines for analysis of cerebrospinal fluid for bilirubin in suspected subarachnoid haemorrhage and a review of other available literature this study has compiled guidance in making the diagnosis. CONCLUSION: In patients presenting with a suspected non-traumatic subarachnoid haemorrhage, computed tomography within 12 hours will reliably show 98% of subarachnoid haemorrhage. In patients who present after 12 hours with a negative computed tomogram, formal cerebrospinal fluid spectophotometry will detect subarachnoid haemorrhage for the next two weeks with a reliability of 96%. Between the early diagnosis with the aid of computed tomography and the later diagnosis with the added benefit of spectophotometry in the period where computed tomograms become less reliable, it should be possible to diagnose most cases of subarachnoid haemorrhage correctly.

Internal carotid blood flow and cerebral hemispheric perfusion in patients with subarachnoid haemorrhage: a study of the quantix/NDtrade mark system and CT perfusion technology.

OBJECTIVE: To assess whether carotid blood flow measurements predict abnormalities in cerebral hemispheric perfusion. DESIGN: The Quantix/NDTM system was used to measure carotid artery blood flow in nine patients with subarachnoid haemorrhage who underwent CT perfusion scanning. RESULTS: No significant correlation was found between internal carotid artery blood flow and ipsilateral cerebral hemispheric perfusion (013, p>0.05) but there was a statistically significant correlation between total internal carotid and global cerebral perfusion (0.63, p<0.05). CONCLUSIONS: This is the first report comparing the Quantix/NDTM system with CT perfusion. Our data do not show a statistically significant correlation between extracranial blood flow and cerebral hemispheric perfusion. This is in contrast to two previous studies where Quantix/NDTM measurements were compared with measurements of cerebral perfusion using the Xenon clearance technique.

Does posterior fossa decompression improve oculomotor and vestibulo-ocular manifestations in Chiari 1 malformation?

BACKGROUND: Oculomotor and vestibulo-ocular manifestations are associated with Chiari 1 malformation. Reports of the results of decompression of CM1 in resolution of these manifestations are limited. METHODS: A retrospective review of case notes were undertaken from Jan 1998 to March 2003 of all the cases undergoing posterior fossa decompressions by the senior author. Forty patients were identified of which 12 had oculomotor and vestibulo-ocular manifestations. RESULTS: Oculomotor and vestibulo-ocular symptoms were present in seven patients and eleven patients had clinical signs. There were only 2 patients who had symptoms and no objective findings. There was complete resolution of oculomotor and vestibulo-ocular manifestations in 8/12 patients and partial improvement in another one, leading to improvement in 9/12 patients. The mean time span to complete resolution was 15.5 months (range 3-71 months). CONCLUSION: Posterior fossa decompression appears to be highly effective in causing complete resolution of disabling oculomotor and vestibule-ocular manifestations in most cases of CM1.