[Guideline "Legal evaluation after closed brain injury in adulthood"]. / Leitlinie "Begutachtung nach gedecktem Schädel-Hirntrauma im Erwachsenenalter".

In 2005 and 2013, the "Deutsche Gesellschaft für Neurowissenschaftliche Begutachtung" (German Society for Neuroscientific Evaluation) together with other societies developed and consented guidelines fort the legal evaluation of patients with closed head injuries and published them trough the National Working Group of Scientific Medical Societies and in this journal. Five years later, a revision was necessary, this was developed on the higher S2 k level of consent through a Delphi conference.

[The German guideline "legal evaluation after closed head injury"]. / Die leitlinie "begutachtung nach gedecktem schädel-hirntrauma".

In 2005, the "Deutsche Gesellschaft für Neurowissenschaftliche Begutachtung" (German Society for Neuroscientific Legal Evaluation) together with other Societies published a guideline for the legal evaluation of patients with closed head injuries. Meanwhile, not only scientific progress in imaging techniques but also in other fields such as neuropsychology has necessitated a revision, which is presented here. In the mean time, the handling of guidelines has been systematised in Germany so that a registration with the Cooperation of German Medical Learned Societies is applied for and publication in the German Guideline Registry is expected.

Konversion eines postoperativen Hypoparathyreoidismus in einen Hyperparathyreoidismus bei ektopem Nebenschilddrüsenadenom.

We present a patient with a history of thyroid cancer, presumably following radiochemotherapy of a childhood medulloblastoma, who developed a primary hyperparathyroidism 10 years after long-term postsurgical hypoparathyroidism. All established imaging modalities failed to detect the origin and only selective neck sampling could identify the suspected parathyroid adenoma causing hyperparathyroidism. This encourages the use of selective neck vein catheterization, particularly in patients with only slightly elevated parathyroid hormone-levels or suspected small ectopic adenoma.

A rare anomaly of the anterior communicating artery complex hidden by a large broad-neck aneurysm and disclosed by three-dimensional rotational angiography.

Double fenestration of the anterior communicating artery (ACoA) complex associated with an aneurysm is a very rare finding and is usually caused by ACoA duplication and the presence of a median artery of the corpus callosum (MACC). We present a patient in whom double fenestration was not associated with ACoA duplication or even with MACC, representing therefore, a previously unreported anatomic variation. A 43 year old woman experienced sudden headache and the CT scans showed subarachnoid haemorrhage (SAH). On admission, her clinical condition was consistent with Hunt and Hess grade II. Conventional digital subtraction angiography (DSA) was performed and revealed multiple intracranial aneurysms arising from both middle cerebral arteries (MCA) and from the ACoA. Three-dimensional rotational angiography (3D-RA) disclosed a double fenestration of the ACoA complex which was missed by DSA. The patient underwent a classic pterional approach in order to achieve occlusion of both left MCA and ACoA aneurysms by surgical clipping. The post-operative period was uneventful. A rare anatomical variation characterised by a double fenestration not associated with ACoA duplication or MACC is described. The DSA images missed the double fenestration which was disclosed by 3D-RA, indicating the importance of 3D-RA in the diagnosis and surgical planning of intracranial aneurysms.

Efficacy of Mechanical Thrombectomy Using Stent Retriever and Balloon-Guiding Catheter.

PURPOSE: Intra-arterial therapy of acute ischemic stroke has developed rapidly in recent years. Due to proven efficacy in randomized trials, stent retrievers were replacing first-generation thrombectomy devices and have been defined as method of choice. However, aspiration catheters or a combination of several techniques have shown promising rates of successful recanalizations. To create a basis for comparison of the new approaches according to real-world data, we determined the first pass recanalization rate of an evidence-based standard technique with the use of a stent retriever in combination with a balloon-guiding catheter. The assessment was based on the number of required passages and reperfusion rate, but not on clinical results. METHODS: Patients from our institution with anterior circulation occlusions and mechanical thrombectomy by using stent retrievers in combination with balloon-guiding catheters were analyzed retrospectively. Reperfusion was graded with the "thrombolysis in cerebral infarction" (TICI) classification on post-interventional angiograms. Additionally, the number of passes and the duration of the recanalization procedure were recorded. RESULTS: Between 2014 and July 2017, 201 patients met the inclusion criteria. Successful recanalization, defined as a TICI scale 2b/3, was 91% (TICI 2b was achieved in 44% and TICI 3 in 47%) after the procedure. After the first passage, successful recanalization was achieved in 65% of the patients. Mean number of passes was 1.4 (1-5 passes) for all patients. Median duration of the procedure was 49 min (0:11-2:35 h). CONCLUSIONS: Even a standard thrombectomy technique with the use of a stent retriever together with a balloon-guiding catheter provides reasonable recanalization rates with only one passage. The results can be taken as benchmark for alternative and more complex techniques.

Conformability of balloon-expandable stents to the carotid siphon: an in vitro study.

BACKGROUND AND PURPOSE: Endovascular placement of coronary balloon-expandable stents in patients with recurrent cerebral ischemia has emerged as a treatment option for intracranial arterial occlusive disease. We have developed an in vitro model matching the tortuous curve of the carotid siphon that allows the assessment of apposition of stents to a curved vessel wall. METHODS: Six types of balloon-expandable coronary stents were implanted in a silicone model of the carotid siphon. Digital radiographs and 3D rotational angiograms were obtained. Stent morphology was evaluated and the degree of apposition between stent and wall of the model was measured on a digital workstation. RESULTS: All 6 stents showed lack of apposition between stent and the wall at the convexity of the anterior segment of the carotid siphon and the wall at the concavity at both extremities of the stent. In and around the curve, the modules of the stents did not expand completely to their nominal diameter and were distorted to an oval shape. CONCLUSION: The tested coronary balloon-expandable stents did not completely conform to the vessel wall of the model of the carotid siphon and further development is needed to approach the goal of an "ideal intracranial stent."

Diffusion-weighted MR imaging lesions after filter-protected stenting of high-grade symptomatic carotid artery stenoses.

BACKGROUND AND PURPOSE: The clinical efficacy of filter devices in internal carotid artery (ICA) stent placement has been a matter of controversy. The aim of this retrospective study was to assess the number and extent of cerebral emboli, as represented by new lesions on diffusion-weighted MR imaging (DWI), in patients treated with filter-protected carotid stent placement. METHODS: Standard DWI (B0 = 1000) was performed within 48 hours before and 48 hours after filter-protected carotid stent placement in 50 patients with symptomatic, high grade (>70%), atherosclerotic ICA stenosis. Number, extent, and vascular territory of new DWI lesions after stent placement were assessed by consensus of 2 experienced neuroradiologists. Multifactorial statistical analysis was performed to determine risk factors associated with DWI lesions. RESULTS: New punctate DWI lesions with a median diameter of 2 mm were detected in 14 of 50 cases in the territory of the stented ICA and in 7 of 50 cases in other vascular territories. Median lesion load was 1 lesion (range, 1-15) per positive case in the stented ICA and 1 lesion (range, 1-7) in other vascular territories. All DWI lesions were clinically asymptomatic. Because of 1 hyperperfusion syndrome with temporary brain swelling, the 30-day stroke and death rate was 2%. Age >or =70 years was the only significant predictor for new DWI lesions, whereas sex, degree and site of stenosis, vascular risk factors, and stent and filter type showed no significant correlation. CONCLUSIONS: New DWI lesions after filter-protected carotid stent placement are substantially more frequent in the ipsilateral ICA territory compared with other vascular territories. Therefore, intraluminal filters cannot completely protect the brain from procedure-related embolization. However, individual lesion load and the risk of clinically relevant ischemia is low.

[Long term follow-up after intracranial vertebro-basilar artery stenting]. / Langzeitergebnisse nach Behandlung intrakranieller vertebrobasilärer Stenosen mit Stents.

PURPOSE: Recurrent ischemic symptoms attributable to intracranial high-grade vertebrobasilar artery stenoses are associated with a high risk of ischemic stroke, particularly if these occur in spite of aggressive medical treatment. Long term efficacy data for endovascular stent angioplasty of symptomatic intracranial stenoses are lacking. The purpose of this prospective study is to determine the rates of deaths, of ischemic events and of restenosis during long-term follow-up. MATERIALS AND METHODS: Between June 2001 and February 2004 twelve patients (11 male, 1 female; median 63 yrs; range, 46 - 75 yrs) with recurrent ischemic symptoms attributed to > or = 70 % intracranial vertebro-basilar artery stenoses, who had failed aggressive medical treatment, were included. Median follow-up was 24 months (range: 6 to 36 months). Intracranial stenoses were measured using 3D rotation angiography data sets and treated with balloon expandable stents. All patients were scheduled for follow-up including clinical (Barthel Index) and transcranial Doppler examinations and intraarterial angiography at 6 months after intervention. Clinical outcome was defined as the rate of stroke in any vascular territory or death during follow-up. Vascular outcome was determined by the rate of in-stent restenosis 50 % on follow-up as examined by intraarterial angiography at 6 months or by transcranial color-coded duplex sonography. RESULTS: Stent placement was technically successful in all patients. No patient had further cerebral ischemic symptoms; two patients died (1 myocardial infarct, 1 sudden death) during follow-up of median 24 months. The degree of stenoses was reduced from median 81 % (range 69 - 94 %) to 19 % (range 10 - 36 %) immediately after stent placement and to 32 % (range 22 - 48 %) after 6 months. No restenosis > or = 50 % occurred during follow-up. CONCLUSION: Based on this limited series, we believe that in patients, with recurrent symptoms despite aggressive medical treatment, endovascular stent placement in intracranial high-grade vertebrobasilar artery stenoses can be an effective and safe treatment option.

Effect of incomplete (spontaneous and postthrombolytic) recanalization after middle cerebral artery occlusion: a magnetic resonance imaging study.

BACKGROUND AND PURPOSE: Early reperfusion is one of the best predictors of good outcome after acute middle cerebral artery (MCA) occlusion. The purpose of this study was to analyze the frequency and relevance of incomplete recanalization for tissue and clinical outcome. METHODS: From a larger acute stroke database (Kompetenznetzwerk Schlaganfall B5), all patients (n=82) with MCA main stem occlusion (excluding carotid T-occlusions) were selected. These patients had received a multiparametric stroke MRI protocol including diffusion- and perfusion-weighted imaging (DWI, PWI) and MR angiography (MRA) within 6 hours after symptom onset, at day 1 and after 1 week. Recanalization status was determined with MRA on day 1 (according to Thrombolysis In Myocardial Infarction flow grades) and used to group patients into those with persistent occlusion (0) or minimal (1), partial (2), or complete (3) recanalization. RESULTS: Incomplete recanalization according to MRI criteria was found in 39 patients (grade 1: n=20; grade 2: n=19), complete recanalization in 10, and persistent occlusion in 33. There was no statistically significant difference in any of the clinical (National Institutes of Health Stroke Scale score) or MRI baseline parameters (DWI lesion, PWI deficit, mismatch volume, mismatch ratio). However, lesion growth was smaller in patients with recanalization (even in patients with only minimal recanalization) and outcome was related to the degree of recanalization (mean modified Rankin score at 90 days: 3.36, 2.70, 1.79, and 1.44 for the groups with no, minimal, partial, and complete recanalization, respectively). Both incomplete and complete recanalization was more frequent in patients receiving thrombolysis. CONCLUSIONS: Incomplete recanalization on day 1 is a frequent MR finding after MCA main stem occlusion, indicating a more favorable clinical course than persistent occlusion. MR indicators of early recanalization could be useful surrogates of efficacy in thrombolytic trials.

[31P-MR spectroscopy of the human liver--the spectral indications of lymphoma infiltration]. / 31P-MR-Spektroskopie der menschlichen Leber--spektrale Hinweise auf eine Lymphominfiltration.

PURPOSE: To evaluate whether phosphorus magnetic resonance spectroscopy (31P-MRS) enables a non-invasive detection of liver involvement in systemic diseases like Hodgkin's lymphoma. MATERIALS AND METHODS: Using a clinical 1.5 Tesla whole-body MR system image-guided localised phosphorus MR spectra from the anatomically defined volumes of interests were measured. A combination of surface coil, adiabatic excitation pulse and modified image-selected in vivo spectroscopy (ISIS)-sequence was applied. The spectroscopy data were evaluated quantitatively with a time-domain fit programme using non-linear optimisation algorithms to quantify peak areas. After establishment of the examination protocol, 22 healthy volunteers and 13 patients with suspected lymphoma infiltration of the liver were examined. RESULTS: Liver spectra of patients suffering from lymphoma infiltration differed significantly from spectra of persons with normal liver: 1. The peak area ratio of phosphomonoesters (PME) to beta-NTP was elevated in all patients with histologically confirmed liver lymphoma. 2. Patients suffering from Hodgkin's disease with specific or unspecific liver infiltration (n = 7) could be differentiated from patients without liver involvement. In case of infiltrated liver, the peak area ratio PME to beta-NTP was increased, and the pH value was shifted to lower values. Unambiguous differentiation between non-specific (n = 3) and specific (n = 4) infiltration of the liver was not possible. 3. In patients after cytostatic treatment (n = 3), an increase of the peak area ratio of inorganic phosphate to beta-NTP was observed. CONCLUSIONS: Our preliminary results indicate that 31P-MRS can yield pointers to liver involvement in patients with systemic diseases such as Hodgkin's disease, which may be hardly detected by imaging methods.

Beyond delayed cerebral vasospasm: infarct patterns in patients with subarachnoid hemorrhage.

PURPOSE: Angiographic vasospasm (CVS) has been accused to be the main cause of delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (SAH). However, treatment success including endovascular treatment remains to be improved. We performed a pattern analysis of ischemic lesions in SAH patients in the absence of angiographic cerebral vasospasm to generate further hypotheses concerning etiology and risk factors of DCI apart from vasospastic narrowing. METHODS: We retrospectively included 309 patients with cerebral infarcts after SAH. Vasospasm was assessed by means of CT or MR angiography and perfusion measurement or digital subtraction angiography. All clinical and radiological data were used to determine the most probable etiology for new infarcts. RESULTS: Twenty-seven percent of patients showed infarcts without presence of angiographic vasospasm. Seventy-three percent of these "atypical infarcts" were induced by complications of aneurysm therapy, 7 % by hypoxia, 2 % by ICP-related herniation. In 17 %, the etiology remained unclear; however, disturbances of the microcirculation for different reasons were the most likely cause in these patients. CONCLUSION: Beyond CVS and treatment complications, a not insignificant number of SAH patients suffered from infarcts of other etiology probably due to disturbance of the microcirculation. Therapeutic approaches for vasodilation of angiographic vasospasm alone should be reconsidered.

Long-term outcome after coil embolization of cavernous sinus arteriovenous fistulas.

BACKGROUND AND PURPOSE: Cranial nerve palsies are regularly observed in patients with arteriovenous fistulas of the cavernous sinus. The purpose of our study was to determine the long-term clinical outcome-with a special focus on extra-ocular muscular dysfunctions-in patients who had undergone endovascular treatment of a cavernous sinus fistula with detachable coils. MATERIALS AND METHODS: Sixteen patients were recalled for an ophthalmoneurologic control examination (mean interval of 4.4 years). The mRS and the EQ-5D questionnaire were used for the description of general outcome. Age, duration of symptoms, character of the fistula (direct, dural), and coil volume were tested to assess their relevance for persistent symptoms. RESULTS: All patients displayed complete regression of chemosis, exophthalmus, and pulsating tinnitus with no evidence of recurrences. Oculomotor disturbances persisted in 9 of 13 patients and caused permanent diplopia in 7 patients. In 15 patients a mRS score of 1 or 2 was achieved; however, 7 patients reported some limitations in life quality (EQ-5D). A significant correlation was found between coil volume and persistent diplopia (P = .032) and persistent cranial nerve VI paresis (P = .037). CONCLUSIONS: Coil embolization of the cavernous sinus led to durable closure of AVF and reliable regression of acute symptoms. However, long-term follow-up showed a 44% rate of persistent cranial nerve deficits with disturbances of oculomotor and visual functions. This may be explained by the underlying fistula size itself and/or the space-occupying effect of the coils. As neuro-ophthalmologic outcome is crucial for control of therapeutic success, patients should be routinely examined by ophthalmologists.

Treatment of symptomatic high-grade intracranial stenoses with the balloon-expandable Pharos stent: initial experience.

INTRODUCTION: We report our first clinical experience with a CE-marked flexible monorail balloon-expandable stent for treatment of high-grade intracranial stenoses. METHODS: Between April 2006 and November 2007 21 patients with symptomatic intracranial stenoses (>70%) were treated with the PHAROS stent. In seven patients, the procedure was performed during acute stroke intervention. Procedural success, clinical complication rates and mid-term follow-up data were prospectively recorded. RESULTS: During a median follow-up period of 7.3 months one additional patient died of an unknown cause 3 months after the intervention. A patient with a significant residual stenosis presented with a new stroke after further progression of the residual stenosis. None of the successfully treated patients experienced ipsilateral stroke. CONCLUSION: Recanalization of intracranial stenoses with the balloon-expandable Pharos stent is technically feasible. The periprocedural complication rate and mid-term follow-up results were in the range of previously reported case series. This pilot study was limited by the small sample size and severe morbidity of the included patients. Final evaluation of the efficacy of Pharos stent treatment demands further investigation.

[Mechanical recanalization in acute stroke treatment]. / Mechanische Rekanalisation beim akuten Schlaganfall.

The development of endovascular techniques for the treatment of acute stroke began with the introduction of local intra-arterial fibrinolysis. In parallel to designing new systemic therapy approaches, catheter systems for loosening, disintegrating, or removing cerebral thrombi have undergone assessment in recent years to serve as alternatives or supplements to fibrinolytic treatment. Mechanical alteration of intracranial thrombi with balloon catheters, manipulations with the guide wire, or ultrasound waves transmitted into the vascular system as well as techniques for thrombus aspiration, snare extraction, or more complex hydrodynamic or laser-guided thrombectomy systems have been tested in feasibility studies, which evidenced basic functionality and relative safety. Broad clinical applications outside of the clinical trial setting cannot yet be recommended since the new catheter systems are still in early phase clinical testing.

Assessment of changes in cerebral circulation time due to vasospasm in a specific arterial territory: effect of angioplasty.

This study demonstrates that in experienced hands, intracranial angioplasty is a feasible and safe option in a selected group of patients with severe (>50% stenosis) symptomatic vasospasm following subarachnoid hemorrhage. Cerebral circulation time is a surrogate parameter closely linked to cerebral perfusion. The study presented shows that not only stenosis but also changes in circulation time are obtained by angioplasty. Twenty angioplasties of one or two vessel segments were performed over 2 years in 18 consecutive patients with posthemorrhagic vasospasm fulfilling criteria for invasive treatment. In all patients, degree of stenosis and circulation time could be reduced by angioplasty. Clinical results were ranked according to Glasgow Outcome Scale. Imaging after 15/20 angioplasties showed no additional infarction. In 4/20 cases, CT showed demarcation of infarction after angioplasty. In 1/20 cases of posterior circulation angioplasty, CT is not sensitive enough to exclude smaller infarctions. Imaging and clinical outcome reveal a definite benefit.

[Stenting in acute stroke]. / Stenting beim akuten Schlaganfall.

Hemodynamic impairment caused by pseudo-occlusion or occlusion of the internal carotid artery (ICA) is a rare etiology of stroke. Acute revascularization of the vessel can restore the flow to the brain. This retrospective study shows that ICA stenting with proximal and distal protection devices in patients with acute stroke and pseudo-occlusion or occlusion of the ICA is technically feasible and can prevent further hemodynamic strokes. In contrast, selected patients have a high risk of reperfusion syndrome with intracranial hemorrhage and peri-interventional monitoring of blood pressure in an ICU is recommended.

[Injuries of the spine: current concepts in radiologic diagnosis]. / Verletzungen der Wirbelsäule: Gegenwärtige Konzepte der radiologischen Diagnostik.

This review discusses the usefulness of plain radiography, computed tomography (CT), and magnetic resonance imaging (MRI) in the evaluation of spinal trauma. The indications for the different imaging modalities in dependence on the specific pattern of injury are explored. Plain radiography still remains the prime method in the diagnosis of acute spinal trauma but there are substantial deficits, especially in the evaluation of the occipitocervical and the cervicothoracic junction as well as in the evaluation of the integrity of the posterior vertebral body line. If injury in these regions is suspected CT should follow plain radiography immediately. In the case of spinal trauma with unexplained neurologic deficits MRI is the method of choice for the detection of spinal cord injury. Recommendations with regard to instability and the classification of specific injuries, including examples of typical findings are presented.

[Stents in the treatment of intracranial atherosclerotic stenoses]. / Stents bei intrakraniellen atherosklerotischen Stenosen.

The treatment of intracranial atherosclerotic stenoses, which account for 10-15% of all ischemic strokes, is technically feasible for few years by the use of new flexible stent devices. Especially patients who fail best medical treatment have a poor prognosis and stenting becomes a reasonable treatment option. Herein we discuss treatment concepts and the principles of stent placement against the background of epidemiology and pathophysiologic basics.

Endovascular recanalization of acute atherothrombotic carotid artery occlusion holds up progressive stroke.

In acute carotid artery occlusion, hemodynamic compromise in addition to artery-artery thromboembolism is the mechanism of ischemia that may lead to a progressive clinical course with enlarging infarcts. The natural course of carotid artery occlusion with a progressive stroke is unfavorable with only about 10% of patients making a good recovery. We report on two patients in whom emergency recanalization of acute carotid artery occlusion with self-expanding stents restored cerebral blood flow and held up progressive stroke.