Anoop Madan

Norfloxacin treatment for clinically significant portal hypertension: results of a randomised double-blind placebo-controlled crossover trial.

Background: While selective intestinal decontamination (SID) can alter the hyperdynamic circulatory state of cirrhosis, the impact of SID on portal pressure remains unclear especially in the setting of clinically significant portal hypertension.

The epidemiology of BCVI at a single state trauma centre

BACKGROUND Blunt carotid and vertebral artery injury (BCVI) is a relatively uncommon but potentially devastating injury. The aim of our study was to highlight the incidence, patterns, presentation and associations of BCVI at our institution. METHODS Retrospective data between 1st January 2003 and 31st December 2006 was obtained from The Alfred Hospitals health information system, patient medical records and the Department of Neurosurgerys database. Injuries were graded using the Denver grading scale. RESULTS 67 patients (0.64%) out of 10,417 minor and major trauma admissions, were diagnosed with BCVI. 33 (49%) sustained blunt carotid and 34 (51%) sustained blunt vertebral injuries. Motor vehicle accident (MVA) was the cause in 43 out of 67. 35% had associated head injury whilst 57% had concurrent cervical spine fractures. Odds ratio analysis showed that MVA victims with concomitant upper cervical spine injury were 22.9 times more likely to suffer BCVI than those without such risk factors. Approximately 50% of patients had a Glasgow coma score of 14 or less (GCS < or = 14). Grade 4 BCVI was most common. Stroke occurred in 22 (32%) and mortality in 14 (20%). CONCLUSION BCVI although infrequent, is a serious injury. Our study suggests that MVA patients with cervical spine fractures especially of the upper C-spine are at much higher risk of BCVI than those without such injuries.

Simultaneous microsurgical and endovascular management of multiple cerebral aneurysms in acute subarachnoid haemorrhage

Most aneurysms can be effectively managed using endovascular coiling or microsurgical clipping, but in an acute subarachnoid haemorrhage where there are multiple aneurysms identified, a sequential multimodal approach may prove more beneficial. This report involves a 31-year-old man who presented with sudden onset of severe headache and photophobia. A computed tomography brain scan revealed a diffuse grade II subarachnoid haemorrhagic pattern, and four-vessel angiography revealed two aneurysms: a right middle cerebral artery bifurcation aneurysm measuring 12 x 8 mm and a 4-mm basilar artery aneurysm associated with a fenestration at the confluence of the vertebral arteries. It was not possible to determine which aneurysm or aneurysms were responsible for the haemorrhage using the customary criteria. The patient underwent sequential endovascular coiling of the vertebrobasilar aneurysm without delay, followed immediately by microsurgical clipping of the right middle cerebral artery aneurysm, under a single anaesthetic. The postoperative course was uneventful. This method is a treatment option for acute subarachnoid haemorrhage where there are multiple aneurysms. It is a logical progression of management that could be employed at any experienced neurovascular centre; the employment of a sequential multimodal approach from the integration of these techniques is beneficial to the patient because it decreases morbidity and mortality.

Numerical Investigation of Hemodynamics of Lateral Cerebral Aneurysm Following Coil Embolization

Abstract Cerebral aneurysms can be treated by coil embolization within the aneurysm sac to alter the local hemodynamics and lower the wall shear stress (WSS) by making the aneurysmal flow inactive. This study investigates the hemodynamics of a lateral wall cerebral aneurysm with coils incorporating fluid-structure interaction (FSI) where the effect of apparent viscosity on thrombus formation is analysed considering the non-Newtonian behaviour of the blood. Three-dimensional transient incompressible laminar flow fields were predicted inside the aneurysm with coils at the proximal and distal neck ends with straight and curved parent vessels. The predictions showed the WSS and the effective stress were highest at the neck region, but the maximum wall displacement occurred at the dome. The coils at the distal neck performed better compared to the coils at the proximal neck in terms of reduced flow rate and higher apparent viscosity. The cerebral aneurysm with coils and curved parent vessel was subjected to higher inflow, displacement and WSS but lower apparent viscosity compared to the one with a straight parent vessel, and therefore has a greater risk of aneurysm wall damage. Hypertension increased the effective stress and displacement on the aneurysm. In patients with hypertension, more emphasis should be placed on ensuring that coils are densely packed at the distal end, especially for curved parent vessels.

Surgical treatment of poorly visualised and complex cerebrovascular lesions using pre-operative angiographic data as angiographic DynaCT datasets for frameless stereotactic navigation

BackgroundDigital subtraction angiography (DSA) is the “gold standard” for the imaging of cerebrovascular lesions, particularly cerebral aneurysms and arteriovenous malformations (AVMs). Current stereotactic navigation is based on computed tomography (CT) and magnetic resonance (MR) images, which—even despite the use of CT angiographic (CTA) or MR angiographic (MRA) sequences—may not reveal small lesions, and may not demonstrate all the different facets of complex lesions.ObjectiveTo develop frameless stereotactic protocols based on pre-operative cerebral angiograms for enhancing precision in intra-operative navigation and improve patient outcomes.MethodsPre-operative angiograms were obtained for ten patients requiring surgery for complex and/or poorly visualised cerebrovascular lesions. The angiographic data were captured as an angiographic DynaCT dataset and fused to pre-operative CT or MR imaging stereotactic sequences for pre-operative planning and intra-operative navigation. The utility of the angiographic DynaCT datasets for surgical navigation and treatment were assessed by the treating neurosurgeon.ResultsThis technique enabled precise navigation and better treatment of cerebrovascular lesions that were either inadequately imaged or invisible to conventional pre-operative CT and/or MR imaging techniques. We found that its use in the surgical excision of a micro-AVM to be far superior to CTA and MRA datasets. Its use in seven cases was found to be superior to CTA and MRA datasets, and as useful as CTA or MRA datasets in two cases.ConclusionPre-operative formal cerebral angiography as an angiographic DynaCT dataset can be used safely and effectively for intra-operative navigation and treatment of cerebrovascular lesions, in particular, micro-cerebral AVMs.

Isolated asymptomatic pulmonary arteriovenous malformation presenting with ischaemic stroke.

Young onset stroke is uncommon, and may be due to conditions other than traditional vascular risk factors. A 42-year-old woman with an ischaemic stroke was found to have left atrial bubble study positivity on transthoracic echocardiogram (TTE) suggestive of patent foramen ovale, however she also had low peripheral oxygen saturation. Investigation revealed an isolated pulmonary arteriovenous malformation (PAVM), visible on admission chest radiograph. This can cause embolic stroke and is an alternate cause of the TTE findings. The PAVM was able to be closed via endovascular intervention, removing the shunt and therefore removing her risk of recurrent stroke events. This is a rare cause of embolic stroke in young people which can be easily missed on investigation yet is amenable to treatment.

Recurrent artery of Heubner aneurysm

True Recurrent artery of Heubner (RAH) aneurysms are extremely rare and only three cases have been reported in the literature. We report a case of RAH aneurysm in a patient with World Federation of Neurosurgical Societies grade one subarachnoid hemorrhage (SAH), detected only on delayed cerebral angiography. We propose that an aneurysm in this location should be considered in the differential diagnosis of angiogram-negative SAH, and all vascular imaging studies be carefully scrutinized for RAH aneurysm