Residual Thromboembolic Material in Cerebral Arteries after Endovascular Stroke Therapy Can Be Identified by Dual-Energy CT.

BACKGROUND AND PURPOSE: Dual-energy CT features the opportunity to differentiate among up to 3 different materials because the absorption of x-rays depends on the applied tube voltage and the atomic number of the material. For example, it is possible to distinguish between blood-brain barrier disruption and an intracerebral hemorrhage following treatment for a stroke. The aim of this study was to evaluate whether dual-energy CT is capable of distinguishing intra-arterial contrast agent from residually clotted vessels immediately after endovascular stroke therapy. MATERIALS AND METHODS: Sixteen patients (9 women, 7 men; mean age, 63.6 ± 13.09 years) were examined. Measurements were made on the postinterventional dual-energy CT virtual noncontrast, iodine map, and "weighted" brain window (weighted dual-energy) series. Postinterventional conventional angiography was used as the criterion standard method. RESULTS: A residual clot was found in 10 patients. On the virtual noncontrast series, the Hounsfield attenuation of the clotted arteries was higher than that in the corresponding perfused contralateral arteries (53.72 ± 9.42 HU versus 41.64 ± 7.87 HU; P < .05). The latter had higher absorption values on the weighted dual-energy series than on the virtual noncontrast series (49.37 ± 7.44 HU versus 41.64 ± 7.87 HU; P < .05). The sensitivity for the detection of a residual clot was 90%; the specificity was 83.3%, and the accuracy was 87.5%. Interrater agreement was good (κ = 0.733). CONCLUSIONS: Dual-energy CT may be valuable in the detection of clot persistence or early re-thrombosis without the necessity of additional contrast administration. However, its relevance for the prediction of outcomes remains to be determined in further studies.

[Treatment of focal dystonia with botulinum toxin A]. / Botulinumtoxin in der Behandlung fokaler Dystonien.

Local injections with Botulinum toxin A (BtxA) are safe and effective in the treatment of focal dystonia. In cervical dystonia and blepharospasm, BtxA injections have become the treatment of choice. However, good results have also been reported with oromandibular dystonia, spasmodic dysphonia and writer's cramp. In cervical dystonia, muscles for injection are selected by clinical presentation or in complex forms with EMG guidance. Several studies have shown that 500 units Dysport are safe and effective in the treatment of cervical dystonia. In blepharospasm, injections are performed in the periorbital part of the orbicularis oculi muscle with good results for 12-14 weeks. The most frequently employed starting dose is 120 units Dysport per eye, divided in three periorbital injection sites. In case of levator inhibition, the pretarsal part of the orbicularis oculi muscle should be injected in a lower dose. EMG guidance is not necessary. By contrast, BtxA treatment of spasmodic dysphonia and writer's cramp require EMG-guided injections in order to avoid side-effects. Dose recommendations for the various types of dystonia are given in the text. In up to 5% of patients with dystonia, the development of neutralising antibodies is reported following repetitive injections with BtxA. Patients with antibodies had a shorter interval between injections, more "boosters", a higher dose per 3-month interval, and a higher total dose injected. In case of neutralizing antibodies against the A toxin, the treatment with Botulinum toxin B (Neurobloc) is a possible alternative.

[Safety and tolerance of single-dose botulinum toxin Type A treatment in 204 patients with spasticity and localized associated symptoms. Austrian and German botulinum toxin A spasticity study group]. / Sicherheit und Verträglichkeit einer einmaligen Botulinum Toxin Typ A-Behandlung bei 204 Patienten mit Spastizität und lokalen assoziierten Störungen. Osterreichische und Deutsche Botulinum Toxin A-Spastik-Studiengruppe.

High dose oral anti-spastic medication is effective in the treatment of spasticity but has the disadvantage of frequent systemic side effects such as drowsiness and general weakness. Therefore, neurolytic and chemodenervation procedures are further therapeutic options, especially in cases of local spasticity. Apart from phenol blocks with the risk of persisting painful dysesthesia, botulinum toxin type A (BtxA) appears to be a safe and effective treatment. In 204 patients (mean age, 41.5 years [range 3-91 years]) with acute (n = 29, mean duration of disease 2.9 months [range, 1-6 months]) and chronic (n = 175, mean duration of disease 111 months [range, 7-500 months]) spasticity due to stroke, traumatic brain and spinal injury and other lesions of the upper motor neuron, the effects of single-dose BtxA treatment were studied. An overall dose of 181.2 units [range, 15-600 units] of BtxA (Botox) was injected in a mean of 3.3 [1-14] muscles per patient. Results were assessed using a modified Rating of Response to BtxA (RRB, Brin et al. 1995). The RRB includes a pre- and post BtxA assessment of the severity of spasticity-associated problems (patient's self-assessment), a rating of the current percentage of normal function in the region of the body selected for BtxA and a global rating of changes induced by BtxA. 191 (93.6%) patients demonstrated improvement over a mean of 7.7 weeks [1-36]; no deterioration was observed. Mean overall severity and function improved significantly (p < 0.001). No systemic or severe side effects were registered. Only in 5.9% of the patients were mild (n = 10) or moderate (n = 2) reversible adverse events reported. We conclude that BtxA injections are safe and effective in the treatment of local spasticity.

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.

Sociocultural differences in gait.

Transcultural differences in routine motor behavior and movement disorders have rarely been assessed. In the present study gait was studied in 47 healthy inhabitants of Tyrol living in rural or semi-urban (Innsbruck, Austria) settings and 43 healthy subjects residing in Berlin, Germany. In addition, gait was assessed in 23 patients in early stages of idiopathic Parkinson's disease (11 in Berlin, 12 in Innsbruck). Healthy subjects in Berlin showed faster gait velocity than their counterparts in Tyrol, and patients with Parkinson's disease were slightly slower than their respective healthy peers in both environments. Surprisingly, patients with Parkinson's disease from Berlin had significantly faster walking speeds than both patients and healthy control subjects from Tyrol. High gait tempo in parkinsonian patients from Berlin was characterized by fast step-rates and short strides. Differences in normal gait in different sociocultural settings are thus reflected in parkinsonian slowing of gait.

[Dysequilibrium in idiopathic Parkinson disease. The effect of cerebrovascular comorbidity]. / Gleichgewichtsstörungen bei idiopathischer Parkinson-Erkrankung. Der Einfluss zerebrovaskulärer Komorbidität.

Disturbance of balance in idiopathic Parkinson's disease (IPD) has a significant effect on disability. Yet the underlying mechanisms and the contribution of age-associated comorbidity to dysequilibrium are unclear. In this study, static posturography was performed in 30 healthy controls and 40 patients with IPD. Comparison of sway during quiet stance did not show significant differences between patients and controls. Multiple linear regression analysis was used to identify factors responsible for the considerable interindividual variance in patients. Results of the pull test, CT-verified cerebral microangiopathy, dementia, and age were assessed, but only cerebrovascular comorbidity contributed significantly to variance. Apart from increased sway, patients with coinciding cerebral microangiopathy (n = 20) more frequently had a history of falls or pathological responses in the pull test. The present results suggest that cerebrovascular comorbidity enhances dysequilibrium in IPD. Pathological sway in IPD can indicate comorbidity and may have implications for further diagnostics.

Comparative analysis of gait in Parkinson's disease, cerebellar ataxia and subcortical arteriosclerotic encephalopathy.

Quantitative gait analysis has been used to elucidate characteristic features of neurological gait disturbances. Although a number of studies compared single patient groups with controls, there are only a few studies comparing gait parameters between patients with different neurological disorders affecting gait. In the present study, gait parameters were compared between control subjects, patients with parkinsonian gait due to idiopathic Parkinson's disease, subjects suffering from cerebellar ataxia and patients with gait disturbance due to subcortical arteriosclerotic encephalopathy. In addition to recording of baseline parameters during preferred walking velocity, subjects were required to vary velocity from very slow to very fast. Values of velocity and stride length from each subject were then used for linear regression analysis. Whereas all patient groups showed slower walking velocity and reduced step length compared with healthy controls when assessed during preferred walking, patients with ataxia and subcortical arteriosclerotic encephalopathy had, in addition, increased variability of amplitude and timing of steps. Regression analysis showed that with changing velocity, subjects with Parkinson's disease changed their stride length in the same proportion as that measured in controls. In contrast, patients with ataxia and subcortical arteriosclerotic encephalopathy had a disproportionate contribution of stride length when velocity was increased. Whereas the findings in patients with Parkinson's disease can be explained as a reduction of force gain, the observations for patients with ataxia and subcortical arteriosclerotic encephalopathy reflect an altered spatiotemporal gait strategy in order to compensate for instability. The similarity of gait disturbance in subcortical arteriosclerotic encephalopathy and cerebellar ataxia suggests common mechanisms.