[Online survey of the organizational structures of emergency neurology in Germany]. / Onlineumfrage zur Struktur der Notfallneurologie in Deutschland 2016.

In 2007, the first poll among neurologists provided some insight into the organizational structures of emergency neurology in Germany. Given that emergency neurology as well as emergency medicine in general have undergone substantial changes during the last decade, the subcommittee Neurological Emergency Medicine of the German Neurological Society conducted a follow-up study to explore current structures supporting neurological emergency medicine in German neurological hospitals. Between July and September 2016, an online questionnaire was e­mailed to 675 neurologists in institutions participating in in-patient neurological care. Of these, some 32% (university hospitals 49%) answered. Neurological patients represent 12-16% and hence a significant proportion of emergency patients. The fraction of in-patients admitted to hospitals via emergency departments amounted to 78% (median) in general hospitals and 52% in university hospitals. Most emergency departments are organized as an interdisciplinary structure combining conservative with surgical disciplines frequently led by an independent department head. Neurology departments employ rather diverse strategies to organize neurological emergency care. Also, the way emergency patients are assigned to different disciplines varied largely. Currently, neurological patients represent a rather growing fraction of patients in emergency departments. An increasing proportion of neurology in-patients enter the hospital via emergency departments. Neurology departments in Germany face increasing challenges to cope with large numbers of neurological emergency patients. While most of the participating neurologists indicated suffering predominantly from scarce personal resources both in neurology and neuroradiology, an independent neurological emergency department was not considered an option.

[The course of early neurological rehabilitation in a patient with severe posterior reversible encephalopathy syndrome]. / Verlauf der neurologischen Frührehabilitation bei einem Patienten mit ausgeprägtem Posteriorem Reversiblem Enzephalopathiesyndrom.

Posterior reversible encephalopathy syndrome (PRES) is widely held to be a benign and potentially reversible disease. However, severe cases have been described in the literature. Data on the long-term outcome of these severe cases are scarce. Furthermore, there are no data focusing on potential benefits of neurological early rehabilitation in these patients. Here we present the clinical picture, neuroimaging features, rehabilitative course and long-term outcome of a patient with severe PRES who underwent early neurological rehabilitation.

Hyperattenuated intracerebral lesions after mechanical recanalization in acute stroke.

BACKGROUND AND PURPOSE: Following mechanical recanalization of an acute intracranial vessel occlusion, hyperattenuated lesions are frequently found on postinterventional cranial CT. They represent either blood or-more frequently-enhancement of contrast agent. Here, we aimed to evaluate the prognostic value of these hyperattenuated intracerebral lesions. MATERIALS AND METHODS: One hundred one consecutive patients with acute stroke in the anterior circulation who underwent mechanical recanalization were included. Risk factors for hyperattenuated intracerebral lesions were assessed, and lesion volume was compared with the volume of final infarction. Clinical outcome and relative risk of secondary hemorrhage were determined in patients with and without any hyperattenuated lesions and compared. RESULTS: The frequency of hyperattenuated lesions was 84.2%. Risk factors for hyperattenuated lesions were female sex, higher NIHSS score on admission, and higher amount of contrast agent applied. On follow-up, 3 patients showed no infarction; 53 patients, an ischemic infarction; and 45 patients, a hemorrhagic infarction. In all except 1 case, final volume of infarction (median = 92.4 mL) exceeded the volume of hyperattenuated intracerebral lesions (median = 5.6 mL). Patients with hyperattenuated lesions were at a 4 times higher relative risk for hemorrhagic transformation but had no significantly worse clinical outcome. CONCLUSIONS: Our data show that the extent of postinterventional hyperattenuated intracerebral lesions underestimates the volume of final infarction. Although hyperattenuated lesions indicate a higher risk of secondary hemorrhagic transformation, their presence seems not to be of any prognostic value regarding clinical outcome.

Time-of-flight angiography: a viable alternative to contrast-enhanced MR angiography and fat-suppressed T1w images for the diagnosis of cervical artery dissection?

OBJECTIVES: To compare the use of an unenhanced high-resolution time-of-flight MR angiography sequence (Hr-TOF MRA) with fat-suppressed axial/coronal T1-weighted images and contrast-enhanced angiography (standard MRI) for the diagnosis of cervical artery dissection (cDISS). METHODS: Twenty consecutive patients (9 women, 11 men, aged 24-66 years) with proven cDISS on standard MRI underwent Hr-TOF MRA at 3.0 T using dedicated surface coils. Sensitivity (SE), specificity (SP), positive and negative predictive values (PPV, NPV), Cohen's kappa (к) and accuracy of Hr-TOF MRA were calculated using the standard protocol as the gold standard. Image quality and diagnostic confidence were assessed on a four-point scale. RESULTS: Image quality was rated better for standard MRI (P = 0.02), whereas diagnostic confidence did not differ significantly (P = 0.27). There was good agreement between Hr-TOF images and the standard protocol for the presence/absence of cDISS, with к = 0.95 for reader 1 and к = 0.89 for reader 2 (P < 0.001). This resulted in SE, SP, PPV, NPV and accuracy of 97 %, 98 %, 97 %, 98 % and 97 % for reader 1 and 93 %, 96 %, 93 %, 96 % and 95 % for reader 2. CONCLUSIONS: Hr-TOF MRA can be used to diagnose cDISS with excellent agreement compared with the standard protocol. This might be useful in patients with renal insufficiency or if contrast-enhanced MR angiography is of insufficient image quality. KEY POINTS: • New magnetic resonance angiography sequences are increasingly used for vertebral artery assessment. • A high-resolution time-of-flight sequence allows the diagnosis of cervical artery dissection. • This technique allows the diagnosis without intravenous contrast medium. • It could help in renal insufficiency or when contrast-enhanced MRA fails.

[Current registry studies of acute ischemic stroke]. / Aktuelle Registerstudien beim akuten ischämischen Schlaganfall.

Study registries offer the opportunity to evaluate the effects of new therapies or to observe the consequences of new treatments in clinical practice. The SITS-MOST registry confirmed the validity of findings from randomized trials on intravenous thrombolysis concerning safety and efficacy in the clinical routine. Current study registries concerning new interventional thrombectomy techniques suggest a high recanalization rate; however, the clinical benefit can only be evaluated in randomized, controlled trials. Similarly, the experiences of the BASICS registry on basilar artery occlusion have led to the initiation of a controlled trial. The benefit of hemicraniectomy in malignant middle cerebral artery infarction has been demonstrated by the pooled analysis of three randomized trials. Numerous relevant aspects are currently documented in the DESTINY-R registry. Finally, the recently started RASUNOA registry examines diagnostic and therapeutic aspects of ischemic and hemorrhagic stroke occurring during therapy with new oral anticoagulants.

The crossed leg sign indicates a favorable outcome after severe stroke.

OBJECTIVE: We investigated whether crossed legs are a prognostic marker in patients with severe stroke. METHODS: In this controlled prospective observational study, we observed patients with severe stroke who crossed their legs during their hospital stay and matched them with randomly selected severe stroke patients who did not cross their legs. The patients were evaluated upon admission, on the day of leg crossing, upon discharge, and at 1 year after discharge. The Glasgow Coma Scale, the NIH Stroke Scale (NIHSS), the modified Rankin Scale (mRS), and the Barthel Index (BI) were obtained. RESULTS: Patients who crossed their legs (n = 34) and matched controls (n = 34) did not differ in any scale upon admission. At the time of discharge, the GCS did not differ, but the NIHSS was better in crossed legs patients (6.5 vs 10.6; p = 0.0026), as was the mRS (3.4 vs 5.1, p < 0.001), and the BI (34.0 vs 21.1; p = 0.0073). At 1-year follow-up, mRS (2.9 vs 5.1, p < 0.001) and the BI (71.3 vs 49.2; p = 0.045) were also better in the crossed leg group. The mortality between the groups differed grossly; only 1 patient died in the crossing group compared to 18 in the noncrossing group (p < 0.001). CONCLUSION: Leg crossing is an easily obtained clinical sign and is independent of additional technical examinations. Leg crossing within the first 15 days after severe stroke indicates a favorable outcome which includes less neurologic deficits, better independence in daily life, and lower rates of death.

Intra-arterial application of nimodipine in reversible cerebral vasoconstriction syndrome: a diagnostic tool in select cases?

INTRODUCTION: Differential diagnoses of the reversible cerebral vasoconstriction syndrome (RCVS) include all forms of intracranial stenotic disease, such as primary or secondary vasculitis of the central nervous system. Here, we tested the hypothesis that angiographic response to intra-arterial nimodipine application may be helpful in differentiating between RCVS and other entities. METHODS: A digital subtraction angiographic (DSA) series of nine consecutive patients with suspected RCVS that were treated by intra-arterial nimodipine due to clinical worsening were retrospectively analyzed. Pre- and post-therapeutic DSA findings of patients with later-confirmed RCVS were compared to those in which another diagnosis was finally made. RESULTS: Intra-arterial nimodipine resulted in a normalization of both the diameter of the main trunks of the cerebral vessels and the caliber of the peripheral vessels in all RCVS patients. This was not the case in the non-RCVS patients, in whom only a slight general vasodilatation was observed. DISCUSSION: Our preliminary results indicate that angiographic response to intra-arterial application might be a helpful differential diagnostic tool in select patients with suspected RCVS.

[New aspects of MRI for diagnostics of large vessel vasculitis and primary angiitis of the central nervous system]. / Neue Aspekte der MRT-Bildgebung zur Diagnostik der Großgefäßvaskulitiden sowie der primären Angiitis des zentralen Nervensystems.

Vasculitis is a rare disease and clinical symptoms are often unspecific. Accurate and early diagnosis is mandatory in order to prevent complications, such as loss of vision or stroke. Imaging techniques can contribute to establishing a definite diagnosis and to evaluate disease activity and the extent of the disease in various vascular regions. Conventional imaging methods, such as computed tomography (CT) and magnetic resonance (MR) angiography, as well as digital subtraction angiography allow the vessel lumen but not the vessel wall to be depicted. However, vasculitis is a disease which primarily affects the vessel wall, therefore conventional imaging modalities often fail to make a definite diagnosis. Recently black-blood high resolution MR in vivo imaging has been used to visualize cervical and intracranial vasculitis. This review article presents imaging protocols for intracranial and cervical black-blood MR imaging and clinical cases with large vessel vasculitis and vasculitis of the central nervous system. Furthermore the current literature, examples of the most common differential diagnoses of cervical and cranial arteriopathy and the potential of other imaging modalities, such as PET/CT and ultrasound will be discussed.

High-resolution black-blood contrast-enhanced T1 weighted images for the diagnosis and follow-up of intracranial arteritis.

Primary arteritis of the central nervous system (CNS) comprises a heterogeneous group of CNS disorders, which is characterised by non-atheromatous inflammation and necrosis of the arterial wall. The clinical presentation is highly variable, with stroke being the most common manifestation. Conventional angiography is considered to be the best imaging tool for diagnosing the disease. However, angiographic findings, which usually show lumen irregularities and stenosis, are often unspecific and can occur with a variety of other vascular disorders, such as atherosclerosis and arterial dissection. Therefore, brain biopsies are often needed to confirm the diagnosis. Recent reports have shown that MRI is able to visualise contrast enhancement in subjects with known primary CNS arteritis.

Progressive encephalomyelitis with rigidity and myoclonus preceding otherwise asymptomatic Hodgkin's lymphoma.

Stiff-person syndrome (SPS), a rare neuroimmunological disorder, is characterized by symmetrical rigidity and muscle stiffness, particularly of axial and proximal limb muscles. Progressive encephalomyelitis with rigidity and myoclonus (PERM) is a variant of SPS which includes additional clinical features (e.g. sensory symptoms, brain stem signs and pathological CSF findings). An association of both SPS and PERM with (solid) malignancies has been previously reported. Beyond this, there have been single reports of SPS in the setting of Hodgkin's lymphoma (HL). Here, we present a case of PERM associated with HL, with PERM preceding occurrence of lymphoma by more than seven months. Our observation has obvious implications for the management and, in particular, diagnostic evaluation of patients with PERM.

Polyneuropathy associated with cholesterol crystal embolism.

INTRODUCTION: Cholesterol crystal embolism complicating arterial catheterization usually presents as a multiorgan disease with renal failure, abdominal problems, and skin manifestations. METHODS: We present a patient with hypertension and generalized arteriosclerosis who presented with muscle weakness, diffuse pain in the extremities, and renal failure 3 weeks after coronary catheterization and angioplasty of the right coronary artery. Muscle weakness progressed during the following months. RESULTS: Nerve conduction studies and nerve biopsy showed severe axonal nerve injury. Biopsy of the kidney revealed the diagnosis of cholesterol crystal embolism. CONCLUSION: The clinical presentation indicates a direct association of cholesterol crystal embolism and polyneuropathy. Although cholesterol crystal embolism represents a rare cause of polyneuropathy, it should be considered in patients with acute onset polyneuropathy and sudden onset multiorgan disease after arterial catheterization.

Noncontrast CT in deep cerebral venous thrombosis and sinus thrombosis: comparison of its diagnostic value for both entities.

BACKGROUND AND PURPOSE: With its highly variable clinical presentation, the diagnosis of cerebral venous sinus thrombosis (SVT), and especially of deep venous thrombosis (DVT), as rare but important causes of stroke is challenging. Because noncontrast cranial CT (NCCT) is still the imaging technique of choice in most emergency departments, we aimed to investigate its value in the diagnosis of SVT and DVT. MATERIALS AND METHODS: Screening our patient data base, we identified 8 patients with DVT and 25 patients with SVT. We also included a control group of 36 patients who had presented with clinical signs of DVT or SVT but in whom thrombosis was subsequently excluded. MR imaging, multidetector row CT angiography (MDCTA), and/or digital subtraction angiography (DSA) were used as the reference standard. Three independent readers assessed the NCCTs for the presence of direct and indirect signs of DVT or SVT. Direct signs included the presence of hyperattenuated sinuses (ie, cord sign) or veins (ie, attenuated vein sign), whereas parenchymal edema and hemorrhage were indirect signs. RESULTS: The sensitivity and specificity of the attenuated vein sign for the diagnosis of DVT were 100%, and 99.4%, respectively, whereas the sensitivity and specificity of the cord sign for SVT were 64.6% and 97.2%, respectively. The sensitivity and specificity values of NCCT were 93.7% and 98% for intracerebral edema and 94.8% and 98.7% for intracerebral hemorrhages, respectively. CONCLUSIONS: Although NCCT is insufficient to exclude a SVT, its value in the emergency diagnosis of DVT seems to be very high.

Mimicking of cerebral herniation through gamma-hydroxybutyric acid therapy.

Besides being a treatment option for narcolepsy, gamma-hydroxybutyrate is used as an adjuvant during anesthesia in Europe. In addition, it is illegally used as a recreational drug. Fixed and dilated, asymmetric pupils developed in 2 patients during continuous therapy with intravenous gamma-hydroxybutyrate, which was added to the long-term anesthetics fentanyl and midazolam. Cerebral herniation as an alternative cause for the pupillary changes was ruled out by using continuous intracranial pressure monitoring and computed tomography. In both patients, the pupillary abnormalities resolved after discontinuation of gamma-hydroxybutyrate. Thus, fixed and dilated pupils that are asymmetric seem to be an important side effect of gamma-hydroxybutyrate therapy that may mimic cerebral herniation in deeply anesthetized patients.

[Complexities of "reversible posterior leukoencephalopathy syndrome"]. / "Reversibles posteriores Leukenzephalopathiesyndrom": Eine unglückliche Begriffsprägung für eine komplexe Erkrankung.

We report a case of reversible posterior leukoencephalopathy syndrome in a 50-year-old patient with severe untreated hypertension. Recent advances in magnetic resonance imaging (especially diffusion-weighted imaging) allow new pathopysiological insight: it was found that the resulting vasogenic edema was restricted neither to the posterior vascular territories nor to white matter. The apparent diffusion coefficient helps to differentiate between reversible vasogenic edema and cytotoxic edema, the latter indicating irreversible neuronal death.