Update on acute endovascular and surgical stroke treatment.

Emergency stroke care has become a natural part of the emerging discipline of neurocritical care and demands close cooperation between the neurologist and neurointerventionists, neurosurgeons, and anesthesiologists. Endovascular treatment (EVT), including intra-arterial thrombolysis, mechanical thrombectomy and angioplasty/stenting, is under rapid development. Although EVT has yet to be shown in randomized controlled trials to improve clinical outcome compared to intravenous thrombolysis, it is far better in achieving recanalization of occluded large cerebral vessels, which is crucial for rescuing the penumbra. Moreover, decompressive craniectomy is now a well-established treatment option for malignant middle cerebral artery infarction and cerebellar stroke. Using a case-based approach, this article reviews recent achievements in advanced treatment options for patients with acute ischemic stroke.

Endovascular embolization of intracranial iatrogenic pseudoaneurysms. A report of two cases and review of the literature.

Iatrogenic pseudoaneurysm is a rare but severe complication of intracranial surgery. Treatment of the condition is difficult. The purpose of this report is to draw attention to the fact that endovascular embolization of pseudoaneurysms with parent artery preservation is possible. We describe two cases of endovascular embolization and review the literature. The conclusion is that endovascular treatment can be safe and curative.

Progressive atrophy of the frontal lobes in first-episode schizophrenia: interaction with clinical course and neuroleptic treatment.

OBJECTIVE: This prospective study examined the interaction of clinical course of disease and brain structure with time in schizophrenic patients. METHOD: A total of 21 first-episode schizophrenic patients, 10 patients with other psychiatric disorders and a control group of 9 healthy volunteers had CT at first admission and at reinvestigation 5 years later. RESULTS: At first admission all of the patients had enlarged cortical fissures and sulci compared to controls, and the duration of untreated psychosis was significantly correlated with sulcal enlargement. At reinvestigation, frontal and central brain atrophy had progressed in schizophrenic patients. CONCLUSION: The study indicated that ongoing psychosis and lifetime dose of classical antipsychotics were the main candidates accounting for the finding of progressively disturbed brain structure during the first 5 years of schizophrenia.

[Whiplash injury syndrome. A prospective study of 39 patients with whiplash injury]. / Piskesmaeldsyndromet. En prospektiv undersøgelse af 39 patienter med piskesmaeldlaesioner.

The acute symptoms after whiplash trauma can be explained by the neck sprain, but the pathogenesis of the "late whiplash syndrome" and the reasons why only some people have persistent symptoms more than six months are still unknown. Thirty-four consecutive cases of piskesmaeld injury were examined clinically three times; respectively within 14 days, after one month and finally seven months post-injury. In addition, MRI of the brain and the cervical spine, neuropsychological tests and motor evoked potentials (MEP) were done one month post-injury and repeated after six months, if abnormalities were found. We found the total recovery rate (asymptomatic patients) was 29% after seven months. All MEP examinations were normal. The correlation between MRI and the clinical findings was poor. Cognitive dysfunction as a symptom of brain injury was not found. Stress at the same time as the accident predicted more symptoms at follow-up. We conclude that long-lasting distress and poor outcome were more related to the occurrence of stressful life events than to clinical and paraclinical findings.

A prospective study of 39 patients with whiplash injury.

INTRODUCTION: The acute symptoms after whiplash traumas can be explained by the neck sprain, but the pathogenesis of the "late whiplash syndrome" and the reason why only some people have persistent symptoms more than 6 months is still unknown. MATERIAL AND METHODS: Thirty-four consecutive cases of whiplash injury were examined clinically three times; within 14 days, after 1 month and finally 7 months postinjury. In addition, MRI of the brain and the cervical spine, neuropsychological tests and motor evoked potentials (MEP) were done one month postinjury and repeated after 6 months, if abnormalities were found. RESULTS: The total recovery rate (asymptomatic patients) was 29% after 7 months. MRI was repeated in 6 patients. The correlation between MRI and the clinical findings was poor. Cognitive dysfunction as a symptom of brain injury was not found. Stress at the same time predicted more symptoms at follow-up. All MEP examinations were normal. CONCLUSION: In this study, long-lasting distress and poor outcome were more related to the occurrence of stressful life events than to clinical and paraclinical findings.

MR velocity mapping measurement of renal artery blood flow in patients with impaired kidney function.

Renal blood flow (RBF) was measured in 9 patients with chronic impaired kidney function using MR velocity mapping and compared to PAH clearance and 99mTc-DTPA scintigraphy. An image plane suitable for flow measurement perpendicular to the renal arteries was chosen from 2-dimensional MR angiography. MR velocity mapping was performed in both renal arteries using an ECG-triggered gradient echo pulse sequence previously validated in normal volunteers. Effective renal plasma flow was calculated from the clearance rate of PAH during constant infusion and the split of renal function was evaluated by 99mTc-DTPA scintigraphy. A reduction of RBF was found, and there was a significant correlation between PAH clearance multiplied by 1/(1-hematocrit) and RBF determined by MR velocity mapping. Furthermore, a significant correlation between the distribution of renal function and the percent distribution of RBF was found.

A segmented K-space velocity mapping protocol for quantification of renal artery blood flow during breath-holding.

Two important prerequisites for MR velocity mapping of pulsatile motion are synchronization of the sequence execution to the time course of the flow pattern and robustness toward loss of signal in complex flow fields. Synchronization is normally accomplished by using either prospective ECG triggering or so-called retrospective gating. However, if the studied vessel moves periodically in space as a result of respiratory motion, as in the case of renal arteries, a second synchronization with respect to the vessel motion in space may be necessary. One method to overcome this problem is to use the segmented k-space technique, in which the entire data acquisition can be made within a breath-hold by the sampling of several phase-encoding lines within a small time window during each heart cycle. The aim of this study was to investigate the performance of a segmented k-space velocity mapping protocol for renal artery flow determination. The protocol uses 16 phase-encoding lines per heart beat during 16 heart cycles and gives a temporal velocity resolution of 160 msec. Comparison with a conventional ECG-triggered velocity mapping protocol was made in phantoms as well as in volunteers. In our study, both methods showed sufficient robustness toward complex flow in a phantom model. In comparison with the ECG technique, the segmentation technique reduced vessel blurring and pulsatility artifacts caused by respiratory motion, and average flow values obtained in vivo in the left renal artery agreed between the two methods studied.(ABSTRACT TRUNCATED AT 250 WORDS)

Ultrasonography in arthritis of the knee. A comparison with MR imaging.

Ultrasonography (US) of the knee in gonarthritis was evaluated with gadolinium-DTPA-enhanced MR imaging as a reference. The study included 13 patients with gonarthritis, 2 patients with osteoarthritis and 5 healthy controls. Compared to MR, US identified 100% (12/12) of joint effusions, 100% (5/5) of Baker's cysts, 57% (8/14) of the synovial membranes of the suprapatellar recess and 38% (3/8) of bone erosions. No MR or clinical findings characterized the patients with ultrasonographically identifiable synovial membranes. Quantitative MR- and US-estimates of effusion, synovial membrane and cartilage thicknesses were correlated. The Spearman correlation coefficients were 0.87, 0.86 and 0.82, respectively. US reliably demonstrated joint effusions and Baker's cysts but showed lack of sensitivity for demonstration of the synovial membrane and bone erosions. When the synovial membrane was identifiable, the measurements of synovial thickness by US appeared precise. Cartilage evaluation by US seemed dependable. The clinical value was limited, because the weight-bearing areas were inaccessible.

[Intracranial venous thrombosis]. / Intrakranial venøs trombose.

Thrombosis of intracranial sinuses and veins is a rare but potentially lethal syndrome. It often affects young adults, but occurs in all ages. It is frequently seen in association with hormonal changes (puerperium, pregnancy and the use of oral contraceptives), inflammatory bowel disease, cancer, and various states of hypercoagulability, or as a consequence of infection. The clinical picture is extremely variable and the diagnosis can be difficult unless one specifically searches for it. The combination of magnetic resonance imaging and magnetic resonance angiography is a powerful and non-invasive tool for diagnosing the syndrome. Treatment with heparin (and for the septic form antibiotics) improves the outcome.

In vivo measurements of proton relaxation times in human brain, liver, and skeletal muscle: a multicenter MRI study.

Quantitative magnetic resonance imaging may offer unique potential for tissue characterization in vivo. In this connection texture analysis of quantitative MR images may be of special importance. Because evaluation of texture analysis needs large data material, multicenter approaches become mandatory. Within the frame of BME Concerted Action on Tissue Characterization by MRI and MRS, a pilot multicenter study was launched in order to evaluate the technical problems including comparability of relaxation time measurements carried out in the individual sites. Human brain, skeletal muscle, and liver were used as models. A total of 218 healthy volunteers were studied. Fifteen MRI scanners with field strength ranging from 0.08 T to 1.5 T were induced. Measurement accuracy was tested on the Eurospin relaxation time test object (TO5) and the obtained calibration curve was used for correction of the in vivo data. The results established that, by following a standardized procedure, comparable quantitative measurements can be obtained in vivo from a number of MR sites. The overall variation coefficient in vivo was in the same order of magnitude as ex vivo relaxometry. Thus, it is possible to carry out international multicenter studies on quantitative imaging, provided that quality control with respect to measurement accuracy and calibration of the MR equipments are performed.

In vivo field dependence of proton relaxation times in human brain, liver and skeletal muscle: a multicenter study.

T1 and T2 relaxation times are fundamental parameters for signal contrast behaviour in MRI. A number of ex vivo relaxometry studies have dealt with the magnetic field dispersion of T1. By means of multicenter study within the frame of the COMAC BME Concerted Action on Tissue Characterization by MRI and MRS, the in vivo field dispersion of T1 and T2 has been measured in order to evaluate whether ex vivo data are representative for the in vivo situation. Brain, skeletal muscle, and liver of healthy human volunteers were studied. Fifteen MR units with a field strength ranging from 0.08 T to 1.5 T took part in the trial, which comprised 218 volunteers. All the MR systems were tested for measurement accuracy using the Eurospin TO5 test object. The measured relaxation data were subsequently corrected according to the obtained calibration curves. The results showed a clear field dispersion of T1, whereas no significant variations were seen for T2. Our in vivo data were generally in reasonable agreement with proposed models based on ex vivo measurements.

[Cerebral toxoplasmosis primarily diagnosed as a tumor]. / Cerebral toksoplasmose primaert diagnosticeret som tumor.

Three cases of cerebral toxoplasmosis as the presenting manifestation of AIDS are reported. The initial diagnoses were brain tumors because of the cerebral mass lesions which resembled glioblastoma. In the light of the increasing occurrence of AIDS, attention is drawn to cerebral toxoplasmosis as a differential diagnosis from glioblastoma multiforme.