Iodinated contrast media and cerebral hemorrhage after intravenous thrombolysis.

BACKGROUND AND PURPOSE: Iodinated contrast is increasingly used in CT perfusion or angiographic examinations in acute stroke. Increased risk of intracranial hemorrhage (ICH) complicating microcatheter contrast injections has recently been reported in the second Interventional Management of Stroke (IMS 2) trial with contrast toxicity potentially contributory. METHODS: We reviewed clinical and radiological data on all patients treated with intravenous alteplase at a single center between May 2003 and November 2008. RESULTS: Of 312 patients treated with intravenous alteplase, 69 (22.1%) received intravenous iodinated contrast in volumes between 50 and 150 mL. Incidence of symptomatic ICH defined as per European Cooperative Acute Stroke Study 2 was 16 of 312 (5.1%; 95% CI, 2.7% to 7.6%); among patients not given contrast, it was 12 of 243 (4.9%; 2.2% to 7.7%) compared with 4 of 69 (5.8%; 0.3% to 11.3%) in those given contrast. Incidence of symptomatic ICH defined as per Safe Implementation of Thrombolysis in Stroke-MOnitoring Study (SITS-MOST) criteria was 12 of 312 (3.9%; 1.7% to 6%), 9 of 243 (3.7%; 1.3% to 6%) among those not given contrast, and 3 of 69 (4.4%; 95% CI, -0.5% to 9.2%) among those given contrast. Patients with symptomatic ICH were older, had higher pretreatment National Institutes of Health Stroke Scale, and blood glucose than those without symptomatic ICH. In logistic regression analysis, pretreatment blood glucose was the only significant predictor of symptomatic ICH by either definition (OR, 1.23; 95% CI, 1.03 to 1.48 per mmol/L increment; P=0.024). Contrast administration or dose was not associated with symptomatic ICH. CONCLUSIONS: Intravenous iodinated contrast in doses typically required for CT angiography and perfusion imaging was not associated with symptomatic intracranial hemorrhage in patients treated with alteplase.

Multidetector computed tomography angiography: Application in vertebral artery dissection.

BACKGROUND AND PURPOSE: Multidetector computed tomography angiography (MDCTA) is a minimally invasive radiological technique providing high-resolution images of the arterial wall and angiographic images of the lumen. We studied the radiological features of vertebral artery dissection (VAD) in a consecutive series of patients investigated for acute stroke and subarachnoid hemorrhage (SAH) in order to confirm and define the diagnostic features of VAD on MDCTA. PATIENTS AND METHODS: Review of patients identified prospectively over a 4-year period with VAD assessed by MDCTA was conducted. Radiological features of VAD on MDCTA were reanalyzed utilising previously reported criteria for VAD. RESULTS: Thirty-five patients (25 males, mean age 49.6 years) with a total of 45 dissected vertebral arteries were reviewed. MDCTA features of VAD included increased wall thickness in 44/45 (97.7%) arteries and increased total vessel diameter in 42/45 arteries (93.3%). All dissected arteries had either lumen stenosis (21/45) or associated segmental occlusion (24/45). An intimal flap was detected in 6/45 (13.3 %) vessels. Twenty-five patients had follow-up imaging, 14/32 vessels returned to normal, 4 showed improvement in stenosis but did not return to normal and 14 demonstrated no change. The majority of non-occluded vessels became normal or displayed improved patency. Only 4/17 occluded arteries demonstrated re-establishment of flow. No adverse effects were recorded. CONCLUSIONS: MDCTA is a safe and reliable technique for the diagnosis of VAD. Increased wall thickness (97.7%) and increased vessel wall diameter (93.3%) were the most frequently observed features.

Involved surgical margins in oral and oropharyngeal carcinoma-an anatomical problem?

A previous audit conducted in the West of Scotland (WoS) suggested that anatomical factors accounted for a substantial proportion of invaded surgical margins after resection of an oral or oropharyngeal squamous cell carcinoma (SCC). Since then a number of technical improvements have taken place, the most important of which has been advanced digital imaging that has enabled better surgical planning. In this study we compare the incidence of involved surgical margins in a recent group with those found in the earlier audit. The earlier (WoS) group comprised a consecutive series of patient operated on for a primary SCC of the oral cavity or oropharynx between November 1999 and November 2001 (n=296). The later series comprised 178 patients operated on for oral or oropharyngeal SCC at the Southern General Hospital (SGH), Glasgow, between 2006 and 2009. A total of 245 patients in the WoS cohort had information available on the invasion of the margins of whom 68 (28%) had an invaded margin. Of 177 patients in the SGH group, 9 (5%) had an invaded margin (p=0.001). An anatomical approach to the resection of oral and oropharyngeal SCC is appropriate, as it results in a rate of invaded margins of less than 10% irrespective of size and site of the primary lesion.

Impact of GP direct-access computerised tomography for the investigation of chronic daily headache.

BACKGROUND: Chronic daily headache is a major healthcare problem, with significant resource implications for specialist services. Since 1999, GPs in Greater Glasgow have had direct access to computerised tomography (CT) for investigation of chronic daily headache. AIM: The purpose of this study is to assess the significance of pathology, impact of the service, and GP satisfaction. METHOD: The direct-access CT findings in patients between 1999 and 2007 were reviewed. Radiological reports were reviewed for abnormal findings by a radiologist. A neurologist reviewed those cases with abnormalities to assess their potential causation in presenting symptoms. A questionnaire was sent to the referring GP for every patient referred for direct-access CT. Data from the Information Services Division of NHS National Services Scotland was used to estimate potential cost benefits. RESULTS: A total of 4404 CT scans were performed. Abnormal findings were reported in 461 (10.5%), and the reported abnormalities were considered a potential causative factor for the presenting symptoms in 60 patients (1.4%). Other abnormalities mostly resulted from established cerebrovascular disease and atrophy; 986 GP questionnaires were analysed. The major body of GP opinion (n = 460, 47%) indicated that direct-access CT was their preferred choice for referral of chronic daily headache. If direct-access CT was not available, neurology (n = 448, 45%) and general medicine (n = 379, 38%) would be the commonest referral choices. This study also reveals that 86% did not require further specialist referral. Projecting the GP questionnaire data to the study group gave an approximate cost saving of at least £86 681.81. CONCLUSION: Direct-access CT is now the preferred choice of management for patients with chronic daily headache in primary care. Patients and GPs are reassured by a normal scan in the majority of cases. There may be cost savings, although confirmation of cost-effectiveness would require further study.

Early recurrent ischemic stroke complicating intravenous thrombolysis for stroke: incidence and association with atrial fibrillation.

BACKGROUND AND PURPOSE: Mechanisms of early neurologic deterioration after treatment with intravenous, recombinant, tissue-type plasminogen activator (IV rt-PA) include symptomatic intracerebral hemorrhage (SICH) and early recurrent ischemic stroke. We observed a number of cases of acute deterioration due to recurrent ischemic events. METHODS: We undertook a single-center, retrospective analysis of consecutive acute stroke patients treated with IV rt-PA between January 2006 and December 2008 to define the incidence of early neurologic deterioration (>or=4-point drop on the National Institutes of Health Stroke Scale within 72 hours) and its mechanism. Deterioration was attributed to SICH when associated with a PH1 or PH2 hemorrhage on postdeterioration computed tomography scans, to recurrent ischemic stroke when there was clinical and radiologic evidence of a new territorial infarction or new vessel occlusion, and otherwise to evolution of the incident stroke. RESULTS: Of 228 consecutive IV rt-PA-treated patients, 34 (15%) developed early neurologic deterioration, 18 (8%) secondary to incident strokes 10 (4.4%) due to SICH, and 6 (2.6%) due to early recurrent ischemic events, which were significantly associated with atrial fibrillation (present in 5 of 6 patients; 4 paroxysmal, 1 permanent). In 4 patients, sudden clinical deterioration developed during or shortly after IV rt-PA infusion, and in 2, deterioration developed 3 days later. All died 2 days to 2 weeks later. The single case without atrial fibrillation had a recurrent, contralateral, middle cerebral artery stroke during IV rt-PA infusion and multiple high-signal emboli detected by transcranial Doppler. Early recurrent ischemic stroke accounted for 5 of 12 (42%) cases of early neurologic deterioration in patients with atrial fibrillation. CONCLUSIONS: In this single-center series, the incidence of early recurrent ischemic stroke after IV rt-PA was 2.6% and was associated with previous atrial fibrillation.

Perimesencephalic nonaneurysmal subarachnoid hemorrhage caused by jugular venous occlusion: case report.

OBJECTIVE: The cause of perimesencephalic nonaneurysmal subarachnoid hemorrhage remains unknown. We describe a patient in whom jugular venous occlusion preceded the occurrence of perimesencephalic nonaneurysmal subarachnoid hemorrhage. This finding supports the theory that the source of the hemorrhage is venous in origin. CLINICAL PRESENTATION: A 25-year-old man presented with sudden onset of headache after his head was held in a headlock during a playful fight 48 hours before the ictus. His computed tomographic (CT) scan on admission demonstrated a perimesencephalic pattern of subarachnoid hemorrhage. CT angiography excluded the presence of an underlying aneurysm or vascular malformation but showed bilateral jugular venous obstruction with hematoma surrounding the right internal jugular vein. Magnetic resonance imaging and a 4-vessel cerebral angiogram confirmed the CT angiographic findings. INTERVENTION: The patient was observed as an inpatient and had no complication of his hemorrhage. Follow-up at 5 months with CT angiography showed resolution of his neck hematoma and reopening of his internal jugular veins. CONCLUSION: The presence of acute jugular venous occlusion as a cause of perimesencephalic nonaneurysmal subarachnoid hemorrhage supports a venous origin of hemorrhage.

Multidetector computed tomographic angiography in isolated third nerve palsy.

OBJECTIVE: To evaluate whether multidetector computed tomographic angiography (CTA) scanners can detect a clinically significant intracranial aneurysm in the circle of Willis causing an isolated third nerve palsy (ITNP). DESIGN: Retrospective cross-sectional study. PARTICIPANTS: One hundred thirty-seven patients who presented with an ITNP were examined by multidetector CTA scanners. METHODS: All patients whose symptoms were caused by a compressive cerebral aneurysm were identified. The remaining patients were observed clinically to exclude the possibility of a missed cerebral aneurysm causing the ITNP. No patient underwent diagnostic conventional cerebral angiography (CCA), but all patients who underwent treatment underwent CCA at the time of the treatment. MAIN OUTCOME MEASURES: Accurate identification of a cerebral aneurysm that may cause an ITNP. RESULTS: A cerebral aneurysm causing an ITNP was detected in 27 patients (19.7%). The smallest maximal diameter of a clinically significant aneurysm was 5.7 mm. Of the 27 patients, 25 underwent endovascular coiling at which time CCA confirmed the aneurysm. In no case was another lesion found by CCA. Of the patients without an aneurysm, 81 of 110 (74%) made a complete spontaneous recovery. In no patient was there clinical evidence to suggest that a compressive cerebral aneurysm had been missed on CTA. CONCLUSIONS: Multidetector CTA is a safe and effective diagnostic imaging tool in detecting clinically significant aneurysms when a patient presents with an acute ITNP. We no longer perform CCA to detect a causative aneurysm or determine the type of treatment offered in these patients.

The role of non-invasive computed tomography in patients with suspected dural fistulas with spinal drainage.

OBJECTIVE: Accurate diagnosis and demonstration of the angioarchitecture and localization of a spinal dural arteriovenous fistula is of crucial importance before treatment. Selective spinal angiography (DSA) has been considered the standard technique, but is invasive, time-consuming, and may be falsely negative. This report evaluates the use of noninvasive vascular imaging (computed tomographic and magnetic resonance angiography [MRA]) in patients suspected to have a dural fistula with spinal drainage. METHOD: Ten consecutive patients had DSA and multidetector computed tomographic angiography (MDCTA), eight also had MRA. Nine were men with an average age of 67 years. In nine patients, the diagnosis was confirmed at surgery or intravascular treatment. Eight were proven to have a spinal dural fistula. In two, the fistula was within the cervical cranial dura. In all patients, the venous drainage involved only the spinal venous plexus. RESULTS: MDCTA identified the level of the feeding artery in nine patients. In two cases, selective DSA failed to show the abnormality found on MDCTA, but both were confirmed at surgery. MRA was diagnostic in a case in which the lesion was not accurately depicted by either MDCTA or DSA. MRA was less accurate than MDCTA in determining the level of the feeding artery. CONCLUSION: MDCTA and MRA can direct and focus DSA. MDCTA gives additional useful three-dimensional bone detail and localization information for the surgeon. It may replace DSA if surgery is the planned treatment.

The familial risk of subarachnoid haemorrhage.

Relatives of people with aneurysmal subarachnoid haemorrhage (SAH) may be at increased risk of SAH, but precise data on the level of risk and which relatives are most likely to be affected are lacking. We studied two samples: 5478 relatives of patients from the whole of Scotland who had a SAH in one year and 3213 relatives of patients with a SAH admitted to the West of Scotland regional neurosurgical unit 10 years previously. Overall, 2% of all relatives in each sample had a SAH. In the Scotland-wide sample, the absolute lifetime risk of SAH (from birth to 70 years) was higher for first-degree relatives [4.7%; 95% confidence interval (CI): 3.1-6.3%] than for second-degree (1.9%; 95% CI: 1.0-2.9%). In the West of Scotland sample, the lifetime risks were very similar to the Scotland-wide sample. The 10-year prospective risk for first-degree relatives alive at the time of the index patient's SAH was 1.2% (95% CI: 0.4-2%) and for second-degree was 0.5% (95% CI: 0.1-0.8%). There was a trend for risk to be highest in families with two first-degree relatives affected and lowest with only one second-degree affected. Most living relatives of patients who suffer a SAH are at low absolute risk of a future haemorrhage; screening is inappropriate except for the few families in whom two or more first-degree relatives, i.e. index case plus one extra have been affected.

Subtraction helical CT angiography of intra- and extracranial vessels: technical considerations and preliminary experience.

BACKGROUND AND PURPOSE: Reported CT angiographic (CTA) subtraction methods are not simple, robust, or real time. We investigated a novel technique for semiautomated digital subtraction CTA of the intracranial and extracranial arteries. METHODS: Thirty patients underwent precontrast (low milliampere-seconds) and postcontrast (pitch, 1.5; collimation, 1-2.5 mm) helical imaging with a vacuum-type head holder to facilitate image registration and minimize movement. A reconstructed three-dimensional model of the precontrast bone dataset was subtracted from the postcontrast dataset to produce subtracted maximum-intensity-projection angiograms. Experienced (operator 1) and less-experienced (operator 2) staff performed the standard and subtraction reconstructions, and image generation time and quality (graded 1-5) were compared. A third operator blinded to the method assessed the hard-copy image quality. RESULTS: Image quality with subtraction postprocessing was significantly better with both operators (operator 1, mean improvement of 0.87 grade, median improvement of 1 grade, P <.001; operator 2, mean improvement of 0.63 grade, median improvement of 1 grade, P <.001). Hard-copy image quality was better with the subtraction method (operator 1, P >.001; operator 2, P <.001). Blood vessels at the base of the brain were better demonstrated on subtraction images in 13 of 14 examinations. For the less experienced operator, the reconstruction time was significantly less with the subtraction method than with the conventional method (mean, 7.5 vs 10.1 minutes; P =.001). CONCLUSION: When separation of the vasculature from bone is important and technically difficult, digital subtraction CTA offers a potential advantage. This semiautomated technique is fast and easy to learn, and variably experienced staff can use it.

The non-invasive detection of intracranial aneurysms: are neuroradiologists any better than other observers?

Can non-neuroradiologists detect intracranial aneurysms as well as neuroradiologists, using CT and MR angiography? Sixty patients undergoing intra-arterial digital subtraction angiography (IADSA) to detect aneurysms also underwent computed tomographic angiography (CTA) and time-of-flight magnetic resonance angiography (MRA). Consensus review of IADSA by two neuroradiologists was the reference standard. Two neuroradiologists, a neurosurgeon, a neuroradiographer and a general radiologist blinded to IADSA, plain CT and clinical data, independently reviewed hard-copy base and reconstructed maximum intensity projection images of the CTA and MRA studies. Thirty patients had a total of 63 aneurysms, 71.4% were