Very urgent carotid endarterectomy does not increase the procedural risk.

OBJECTIVES: The timing of CEA for symptomatic internal carotid artery (ICA) stenosis remains a matter of controversy. Recent registry data showed a significantly increased risk, especially in the very early days after the onset of symptoms. In this study the outcome of CEA in the hyperacute phase has been investigated. METHODS: The outcome of CEA for symptomatic ICA stenosis between January 2004 and December 2013 has been retrospectively analyzed. Patients were divided into four timing groups: surgery within 0 and 2 days, between 3 and 7 days, 8 and 14 days, and thereafter. The post-operative 30 day stroke and death rates were assessed. RESULTS: A total of 761 symptomatic patients (40.1% with transient ischemic attack [TIA], 21.3% with amaurosis fugax, and 38.6% with ischemic stroke) were included, with an overall peri-operative stroke and death rate of 3.3%. A stroke and death rate of 4.4% (9/206) for surgery within 0 and 2 days, 1.8% (4/219) between 3 and 7 days, 4.4% (6/136) between 8 and 14 days, and 2.5% (5/200) in the period thereafter (p = .25 for the difference between the groups) was observed. The timing of surgery did not influence the peri-operative outcome in a multivariate regression analysis (OR 0.93 [0.63-1.36], p = .71). CONCLUSIONS: These data show that very urgent surgery in symptomatic patients can be performed without increased procedural risk. Given the fact that ruptured plaques with neurological symptoms carry the highest risk of a recurrent ischemic event in the first 2 days, treating patients as soon as possible to offer the highest benefit in stroke prevention is recommended.

Carotid endarterectomy within seven days after the neurological index event is safe and effective in stroke prevention.

BACKGROUND: Timing of surgery remains a controversial subject with some concerns persisting that the benefit of early carotid endarterectomy (CEA) offsets the perioperative risks. We investigated the neurological outcome of patients with symptomatic internal carotid artery (ICA) stenosis after surgery in relation to the timing of treatment. METHODS: From January 2005 to June 2010, 468 patients (n = 349 male, 74.6%, median age 71 years) underwent CEA for symptomatic stenosis. Perioperative morbidity and mortality rates were assessed in the 30 days' follow-up. RESULTS: The median time interval between index event and CEA was 7 days; the overall stroke and death rate reached 3.4%. There was no difference in the 30 days' rate of stroke /death rate, depending on the timing of surgery (n = 5/241, 2.1% in patients treated within 1 week vs. n = 10/215, 4.7% in patients treated thereafter, p = 0.12). Patients with a postoperative neurological deterioration had more often an ischaemic infarction on preoperative cerebral computed tomography (CCT) compared with those without deterioration (n = 6/15, 40.0% vs. n = 39/441, 9.0%, p = 0.003). Logistic regression analysis showed that patients with preoperative infarction on CCT had the highest risk for postoperative neurological deterioration. CONCLUSION: An infarction on the preoperative CCT leads to an increased risk for a postoperative deterioration after CEA. Patients should be treated at an early point in time with bland CCTs.

Basilar artery dissection: series of 12 consecutive cases and review of the literature.

BACKGROUND: Current knowledge on primary or isolated basilar artery dissection (IBAD) is limited to case vignettes and small patient series. OBJECTIVE: To delineate the frequency and clinical presentations of IBAD along with short-term outcome, specific prognosis and targeted management. METHODS: Data were derived from a series of 12 consecutive patients and a review of 88 cases reported in the literature. In all the cases, the dissection was confined to the basilar artery. RESULTS: Disease incidence was estimated at 0.25 per 100,000 person-years. IBAD accounted for roughly 1.0% of all subarachnoid hemorrhage events and for no less than 10.5 and 4.5% of posterior circulation and brain-supplying artery dissections, respectively. The main clinical presentations were subarachnoid hemorrhage (46%) and posterior circulation brain ischemia (42%). Subarachnoid hemorrhage typically manifested at a higher age than brain ischemia (mean age, 48.9 vs. 41.4 years) and was more prevalent among women. Rebleedings related to pseudoaneurysm formation in patients with subarachnoid hemorrhage and recurrent ischemia in stroke patients were common in the acute phase (26.1 and 33.3%, respectively) but were rare in the long term. The outcome was generally favorable in stroke patients but variable in subarachnoid hemorrhage (case fatality rate, 21.7%). The mainstay of therapy for subarachnoid hemorrhage related to IBAD was endovascular occlusion of the aneurysm pouch whereas stroke patients were usually put on anticoagulants. CONCLUSIONS: IBAD is probably an underrecognized disease with heterogeneous clinical presentation and prognosis. It should be considered as a differential diagnosis in peritruncal subarachnoid hemorrhage, classic subarachnoid hemorrhage and posterior circulation stroke, especially in young individuals. Case management is challenging and has to be tailored to each patient.

Relationship of high-density lipoprotein subfractions and cholesteryl ester transfer protein in plasma to carotid artery wall thickness.

High plasma concentrations of high-density lipoprotein (HDL) cholesterol are a powerful indicator of low vascular risk. By decreasing HDL cholesterol, cholesteryl ester transfer protein (CETP) could perhaps constitute an atherogenic protein. We measured HDL cholesterol and HDL subfractions and quantified CETP mass in fasting plasma in 21 asymptomatic probands, and related these variables to the mean intima media thickness of the extracranial carotid arteries. HDL2 cholesterol, the less dense HDL subfraction, was inversely related to carotid wall thickness (r = -0.378; P < 0.05), and CETP was directly related to carotid wall thickness (r = 0.436; P < 0.05). In plasma CETP is associated mostly with the HDL3 subfraction. We therefore calculated from our measurements the relative CETP content of HDL3, i.e., CETP/HDL3 cholesterol. This ratio was correlated with carotid wall thickness stronger than any other variable measured (r = 0.718, P < 0.001). We conclude that variation in HDL subfractions and CETP may be more closely associated with carotid intima media thickness than the accepted strong risk factor of HDL cholesterol.

Menstrual cycle dependent right-to-left shunting: a single-blinded transcranial Doppler sonography study.

BACKGROUND AND PURPOSE: Menstruation has been described as risk factor for neurological decompression sickness in divers. In considering this for paradoxical gas embolism, we hypothesized that there may be a link between cycle-dependent hormonal changes and the manifestation of a right-to-left shunt (RLS). METHODS: 40 women with a regular cycle of 28 days underwent transcranial Doppler sonography examinations (TCD) on day 1 and on day 15 of the menstrual cycle. Cerebral high intensity transient signs (HITS) proved a RLS. RESULTS: We found a 25% RLS incidence consistent with the literature. In 7 of 10 shunt-positive women it was detected mainly or exclusively on day 15. This difference in PFO detection rate is statistically significant (p = 0.031), indicating more RLS during the peri-ovulatory period. CONCLUSIONS: Our results do not support menstruation as a risk factor for neurological decompression sickness. The peri-ovulatory estrogen peak, which leads to systemic vasodilation, may explain our data. Factors that increase the risk for developing a RLS and thereby paradoxical embolism should be avoided, perhaps including diving during the peri-ovulatory period of the menstrual cycle. Furthermore, contrast PFO testing in fertile females may be most sensitive if conducted mid-cycle.

Transcranial Doppler sonography guided by magnetic resonance angiography for improved monitoring of intracranial arteries.

Transcranial Doppler (TCD) sonography combines the advantages of real-time hemodynamic information, cost-effectiveness, and bedside application. However, measurements can be difficult to reproduce because the spatial resolution and the determination of insonation angles are limited. The purpose of this study was to use the high anatomic resolution of three-dimensional (3D) magnetic resonance angiography (MRA) images for the stereotactic guidance of TCD in order to improve the accuracy and reproducibility of TCD examinations. The MRA examinations were performed on a 1.5 T scanner using a 3D flow compensated gradient-echo sequence. A noninvasive stereotactic mask was used for image registration. The MRA data were then transferred to a personal computer. An infrared tracking system registered the position of the head and the ultrasound probe during TCD. This enabled the authors to superimpose a virtual ultrasound beam onto the MRA projections of the intracranial arteries displayed on the monitor of the personal computer. This allows the examiner to easily identify the insonated intracranial artery and displays the insonation angle. In volunteer examinations (n = 10), the accuracy and reproducibility for the localization of specific vessel segments was 2.48 mm for the middle cerebral artery and 2.81 mm for all insonated intracranial arteries (middle cerebral artery, anterior cerebral artery, internal carotid artery, and posterior cerebral artery). Without navigation the reproducibility of vessel segment insonation dropped to 4.7 mm for the middle cerebral artery and to 4.84 mm for all vessels. The authors conclude that 3D MRA, acquired as an initial procedure in patients with intracranial vascular disorders, can be used to provide stereotactic guidance for repeated TCD examinations. This facilitates the reproducible insonation of specific vessel segments.

Effects of normo- and hypocapnic nitrous-oxide-inhalation on cerebral blood flow velocity in patients with brain tumors.

Nitrous oxide (N2O) use during anesthesia for intracranial procedures has been a subject of controversy in the past. To date, the isolated influence of N2O on mean cerebral blood flow velocity in the middle cerebral artery (VMCA) has not been investigated during hypocapnia in patients with brain tumors. We compared VMCA during normocapnic (ETCO2: 40 mm Hg) and hypnocapnic (ETCO2: 25 mm Hg) inhalation of air and 50% nitrous oxide in oxygen N2O/O2 in eight patients with unilateral brain tumors on both the tumor side and the healthy side. Six patients completed the study. Mean VMCA increased during normocapnic inhalation of N2O/O2 (tumor side: 86 +/- 16 cm sec-1; healthy side: 74 +/- 17 cm sec-1) when compared with air (tumor side: 72 +/- 18 cm sec-1; healthy side: 62 +/- 14 cm sec-1, p < 0.01), whereas during hyperventilation VMCA decreased on both sides (p < 0.001). Mean VMCA values were quite similar during hypocapnic inhalation of 50% N2O/O2 (tumor side: 50 +/- 12 cm sec-1; healthy side: 45 +/- 13 cm sec-1) and air (tumor side: 51 +/- 14 cm sec-1; healthy side: 45 +/- 12 cm sec-1). The data of our study suggest that in patients with cerebral tumors the N2O-induced increase in mean VMCA can be completely reversed by hyperventilation.

Hypocapnia reverses the fentanyl-induced increase in cerebral blood flow velocity in awake humans.

Investigations on the effects of opioids on cerebrovascular dynamics have repeatedly demonstrated mild to moderate increases in cerebral blood flow velocity in the middle cerebral artery (CBFVMCA), cerebral blood flow, and cerebrospinal fluid pressure in humans and animals. However, the influence of hypocapnia on these fentanyl effects has not been investigated. We compared mean CBFVMCA during normo- and hypocapnia before and after administration of fentanyl (2.5 micrograms/kg i.v.) in 20 awake humans. During normocapnia (end-tidal carbon dioxide [ETCO2] 40 mmHg) fentanyl significantly increased mean CBFVMCA (60 +/- 10 cm/s vs. 81 +/- 12 cm/s [mean +/- SD]; p < 0.01), whereas during hypocapnia (ETCO2 25 mmHg) mean CBFVMCA values were identical (40 +/- 7 cm/s vs. 40 +/- 7 cm/s) before and after fentanyl administration. These results confirm previous findings that administration of fentanyl increases CBFVMCA, but, more importantly, clearly indicate that hypocapnia reverses this potentially undesirable effect.

[The role of sonography and MR tomography in the diagnosis and therapeutic control of the carpal tunnel syndrome]. / Der Stellenwert von Sonographie und MR-Tomographie in Diagnose und Therapiekontrolle des Karpaltunnelsyndroms.

120 wrists of 105 patients with carpal tunnel syndrome were studied preoperatively by high-resolution sonography. Follow-up examinations after carpal tunnel release were performed in 72 wrists. In addition, 40 wrists were examined preoperatively, and 20 wrists were examined postoperatively by MR imaging. Based on quantitative analysis of the cross-sectional area and shape of the median nerve and of the palmar bowing of the flexor retinaculum, sonography established the diagnosis in 95% of cases. MR was superior in the evaluation of mild degrees of median nerve compression, and in the detection of possible causes of the carpal tunnel syndrome, such as synovitis of the flexor tendon sheaths or ganglionic cysts. In postoperative follow-up, sonographic demonstration of a normally flattened median nerve was an excellent indicator of the successful carpal tunnel release. In 10 patients with persistent or recurrent symptoms after carpal tunnel release, the underlying pathology could be exactly demonstrated by MR.

Cerebral vasospasm following temporal lobe epilepsy surgery.

OBJECTIVE: Selective amygdalohippocampectomy (AHE) has been associated with postoperative cerebral vasospasm (CVS) in patients with medically intractable temporal lobe epilepsy. The incidence in temporal lobe resection (TLR) is unknown. This retrospective cohort study evaluates the incidence of and risk factors for the development of CVS in patients with TLR and AHE. METHODS: A total of 119 patients were included between 1998 and 2009. All patients were evaluated by standardized preoperative and postoperative transcranial Doppler sonography (TCD) evaluations and neurologic examinations. Postoperative CT scans were evaluated by an independent radiologist and the volume of bleeding within the resection cavity was quantified. RESULTS: Of 107 patients with longitudinal TCD data, 35 (32.7%) developed postoperative CVS. The incidence of CVS did not differ between patients with TLR and AHE. CVS was associated with female gender and a higher bleeding volume in the postoperative CT scan (p = 0.035 and 0.046). Patients with CVS showed a significantly higher incidence of postoperative neurologic signs and symptoms (48.6%) compared to patients without CVS (25%, p = 0.015). The mean length of stay was significantly prolonged in patients with diffuse CVS compared to patients with localized CVS or no CVS (28.8 ± 10.9, 24.2 ± 6.6, and 18.2 ± 6.1 days, p < 0.001). CONCLUSION: CVS is a frequent complication of surgery for temporal lobe epilepsy irrespective of the resection method. Important risk factors for the development of postoperative CVS are female gender and a higher amount of bleeding in the postoperative CT. Patients with CVS more frequently have neurologic signs and symptoms resulting in prolonged hospital stay.

Functional recovery after ischemic stroke--a matter of age: data from the Austrian Stroke Unit Registry.

OBJECTIVE: To analyze the association between patient age and good functional outcome after ischemic stroke with special focus on young patients who were numerically underrepresented in previous evaluations. METHODS: Of 43,163 ischemic stroke patients prospectively enrolled in the Austrian Stroke Unit Registry, 6,084 (14.1%) were ≤55 years old. Functional outcome was available in a representative subsample of 14,256 patients free of prestroke disability, 2,223 of whom were 55 years or younger. Herein we analyzed the effects of age on good functional outcome 3 months after stroke (modified Rankin Scale score ≤2). RESULTS: Good outcome was achieved in 88.2% (unadjusted probability) of young stroke patients (≤55 years). In multivariable analysis, age emerged as a significant predictor of outcome independent of stroke severity, etiology, performance of thrombolysis, sex, risk factors, and stroke complications. When the age stratum 56-65 years was used as a reference, odds ratios (95% confidence interval [95% CI]) of good outcome were 3.4 (1.9-6.4), 2.2 (1.6-3.2), and 1.5 (1.2-1.9) for patients aged 18-35, 36-45, and 46-55 years and 0.70 (0.60-0.81), 0.32 (0.28-0.37), and 0.18 (0.14-0.22) for those aged 66-75, 76-85, and >85 years (p < 0.001). In absolute terms, the regression-adjusted probability of good outcome was highest in the age group 18-35 years and gradually declined by 3.1%-4.2% per decade until age 75 with a steep drop thereafter. Findings applied equally to sexes and patients with and without IV thrombolysis or diabetes. CONCLUSIONS: Age emerged as a highly significant inverse predictor of good functional outcome after ischemic stroke independent of stroke severity, characteristics, and complications with the age-outcome association exhibiting a nonlinear scale and extending to young stroke patients.

Recanalization after thrombolysis in stroke patients: predictors and prognostic implications.

OBJECTIVE: To estimate rates, predictors, and prognostic importance of recanalization in an unselected series of patients with stroke treated with IV thrombolysis. METHODS: We performed a CT angiography or transcranial Doppler (TCD) follow-up examination 24 hours after IV thrombolysis in 64 patients with documented occlusion of the intracranial internal carotid or middle cerebral artery (MCA). Complete recanalization was defined by a rating of 3 on the Thrombolysis in Myocardial Infarction or 4/5 on the Thrombolysis in Brain Ischemia grading scales. Information about risk factors, clinical features, and outcome was prospectively collected by standardized procedures. RESULTS: Complete recanalization was achieved in 36 of the 64 patients (56.3%). There was a nonsignificant trend of recanalization rates to decline with a more proximal site of occlusion: 68.4% (M2 segment of MCA), 53.1% (M1 segment), and 46.2% (carotid T) (p for trend = 0.28). Frequencies of vessel reopening were markedly reduced in subjects with diabetes (9.1% vs 66.0% in nondiabetics, p < 0.001) and less so in subjects with additional extracranial carotid occlusion (p = 0.03). Finally, complete recanalization predicted a favorable stroke outcome at day 90 independently of the information provided by age, NIH Stroke Scale, and onset-to-needle time. CONCLUSIONS: We found a high rate of vessel recanalization after IV thrombolysis occlusion. However, recanalization was infrequent in patients with diabetes and extracranial carotid occlusion. Information on recanalization was a powerful, early predictor for clinical outcome.

Carotid endarterectomy after ischemic stroke--is there a justification for delayed surgery?

PURPOSE: To assess the relationship between outcome of carotid surgery and wait after ischemic stroke. METHODS: We retrospectively analysed data from patients undergoing carotid endarterectomy after ischemic stroke. We investigated the time interval between the event and endarterectomy in relation to surgical results and complications. RESULTS: Between January 2000 and December 2003, 104 patients were scheduled to undergo carotid endarterectomy after a recent stroke. Endarterectomy was performed within 6 h in seven patients (6.7%); within 4 weeks in 29 (27.9%); 4 weeks or more in 62 (59.6%) and six (5.8%) patients received no further therapy. Perioperative complications among patients treated within 4 weeks were 3.4% and were comparable to those treated after 4 weeks (4.8%). However, more than 12% of the patients awaiting operation experienced a new cerebrovascular event (ischemic stroke or carotid occlusion), most of them occurred in the 3rd or 4th week after the initial event. CONCLUSION: Our data indicates, that carotid endarterectomy can be performed with a comparable risk within a short delay after stroke. In addition severe cerebrovascular events occurring within the waiting period may be avoided.

Acute cerebellar ataxia after immunisation with recombinant hepatitis B vaccine.

We report one woman with acute cerebellar ataxia (ACA), a well-defined clinical syndrome, which occurred 10 days after the second vaccination with recombinant hepatitis B vaccine. The patient had no previous symptoms or signs of neurological disease and there was no evidence of neurologic disease in the family history. Within nine months the symptoms remitted completely according to other reports of ACA. As there was a close temporal connection and no noticeable other cause we assume a causal link between the vaccination and the disease. As far as we known this is the first case of ACA after hepatitis B vaccination.

[Membranous lipodystrophy (Nasu-Hakola disease)]. / Membranöse Lipodystrophie (Morbus Nasu-Hakola).

We present a case-report and review of the literature on membranous lipodystrophy. This is a rare disease characterized by progressive presenile dementia, multiple bone cysts with pathologic fractures, generalized cerebral seizures with abnormal EEG and bilateral calcifications of the basal ganglia. Neuropathological findings are neuroaxonal dystrophy with neurofilaments in the axons, neuronal cell loss and fibrillary gliosis. The disease is usually inherited as an autosomal recessive. The pathogenesis is unknown but is believed to be an enzyme defect of the glycolipid metabolism.

Hyperventilation reverses the nitrous oxide-induced increase in cerebral blood flow velocity in human volunteers.

Because hypocapnia is routine during general anaesthesia for intracranial procedures, we have compared, in 13 healthy volunteers, the effect of normocapnia (PE'CO2 5.3 kPa) and hypocapnia (PE'CO2 3.3 kPa) on mean blood flow velocity in the middle cerebral artery (Vmca) during normoventilation and hyperventilation with air and with 50% nitrous oxide in oxygen. After replacement of air with 50% nitrous oxide in oxygen, there was an increase in mean Vmca during normoventilation (air: mean 68.23 (SD 16.98) cm s-1 vs nitrous oxide in oxygen: 90.69 (20.41) cm s-1; P < 0.01), whereas during hyperventilation mean Vmca values were similar regardless of the inhaled gas mixture (air: 43.46 (9.97) cm s-1 vs nitrous oxide in oxygen: 41.69 (8.08) cm s-1. Our data suggest that the nitrous oxide-induced increase in mean Vmca can be blocked by hyperventilation.

Hereditary vitreoretinal dystrophy associated with peripheral neuropathy.

Autosomal dominant inherited vitreoretinal dystrophy has been reported to occur as isolated ocular disease (Wagner's disease) or in combination with systemic manifestations (e.g., Stickler's syndrome). We examined five members of one family (three generations) and found vitreoretinal dystrophy and non-ocular signs in a mother and her two children. In the mother we also observed tractional detachment of the macula. In addition to routine ophthalmological examinations, we performed electrophysiological tests (ERG, EOG), adaptometry and magnetic resonance imaging of the head. Neurological examination revealed peripheral neuropathy in the mother and her children. We had no evidence that the neuropathy had a toxic or metabolic origin, and other genetically determined neuropathies were unlikely based on the clinical picture, MRI, and laboratory tests. Therefore, the neuropathy might be either a hitherto unrecognized feature of a variant of Stickler's syndrome or part of a yet unclassified hereditary vitreoretinal dystrophy with systemic involvement.

[Increasing value of the duplex scan in preoperative diagnosis of the carotid artery--is preoperative carotid angiography still sensible?]. / Die zunehmende Bedeutung des Duplex Scans in der präoperativen Carotisdiagnostik--ist die präoperative Carotisangiographie noch sinnvoll?

In effort to eliminate morbidity and costs, associated with arteriographic investigation, we increasingly perform Duplex Scan of the extracranial carotid artery prior to endarterectomy. 451 carotid reconstructions between 1986 and April 1991 were evaluated retrospectively. The percentage of patients undergoing carotid endarterectomy without angiography has increased from 21.1% to 92.8%. Angiography was associated with a combined neurologic morbidity rate of 3.0%. Perioperative outcome of patients and stratification by indication did not show any significant differences for both groups undergoing Duplex Scan alone and/or angiography. Diagnostic Carotid angiography should only be used selectively in patients showing distal internal carotid plaque, recurrent stenosis, symptomatic carotid occlusion or aortic arch disease.

Carpal tunnel syndrome: diagnosis with high-resolution sonography.

OBJECTIVE: Carpal tunnel syndrome is characterized by typical anatomic changes that can be shown with high-resolution sonography. To determine whether these findings are reliable and can be used to establish the diagnosis, sonograms of patients with the disease were compared with sonograms obtained in patients with normal wrists. Also compared were sonograms and MR images obtained in the patients with carpal tunnel syndrome. SUBJECTS AND METHODS: Twenty wrists in 18 consecutive patients with clinical symptoms of carpal tunnel syndrome and with abnormal nerve conduction studies were examined with real-time sonography and MR imaging. The sonograms and MR images were evaluated quantitatively by two unbiased observers with regard to the size and shape of the median nerve and the palmar bowing of the flexor retinaculum. A t test was used to compare these data with those from previous sonographic studies of 28 normal wrists. Correlation coefficients for the measurements obtained with sonography and with MR were calculated. The relative accuracies of different diagnostic criteria for the diagnosis of carpal tunnel syndrome were assessed by using receiver-operating-characteristic analytical techniques. RESULTS: Characteristic findings on both MR and CT scans of the 20 wrists with carpal tunnel syndrome included swelling of the median nerve in the proximal part of the carpal tunnel in 16 wrists, flattening of the median nerve in the distal part of the carpal tunnel in 13 wrists, and increased palmar bowing of the flexor retinaculum in nine wrists. Comparison with the data of 28 normal wrists proved that these findings were significant (p less than .01 to p less than .001). Receiver-operating-characteristic analysis showed that the discrimination between wrists in normal subjects and in patients with carpal tunnel syndrome achieved with each of the three diagnostic criteria was not significantly different. Measurements of the size and flattening of the median nerve obtained from sonograms were similar to those on MR images, whereas sonography was less accurate for measuring the palmar bowing of the flexor retinaculum. CONCLUSION: We conclude that the results of sonography are reliable, and that the diagnosis of carpal tunnel syndrome can be established on the basis of sonographic findings.