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W Küker

Publications and source records attributed to W Küker.

At least 19 recordsLinked to original sources
PubMed2004

Diffusion-weighted MRI in herpes simplex encephalitis: a report of three cases.

Herpes simplex virus encephalitis (HSVE) is the most frequent fatal viral infection of the brain. Because antiviral treatment may improve the prognosis significantly, early diagnosis is mandatory. Imaging diagnosis rests on conventional MRI for the visualization of lesions in the limbic system, the hallmark of HSVE. Diffusion-weighted MRI (DW-MRI) has not been used for the evaluation of HSVE. We report on the DW-MRI findings in three patients with HSVE, who had cortical diffusion abnormalities in affected brain parenchyma, partially as the initial or most sensitive sign of encephalitis. Sequential imaging showed that the diffusion abnormality started to return to normal after 2 weeks in the presence of persistent contrast uptake. Thus, DW-MRI may be a valuable tool for early detection and diagnosis of HSVE whereas contrast-enhanced images are indispensable after the first week.

Aged↗
PubMed2003

Progressive multifocal leukoencephalopathy: analysis of lesion development with diffusion-weighted MRI.

Progressive multifocal leukoencephalopathy (PML), caused by replication of JC virus in oligodendrocytes of immunocompromised patients, is diagnosed by polymerase chain reaction-based demonstration of JC virus DNA. We investigated whether MRI might be used to assess disease activity. Diffusion-weighted imaging (DWI) was obtained in two patients with PML, in whom it was the only MRI sequence on which we could identify areas of progressive disease. The extent of abnormal diffusion appeared to correlate with the speed of clinical progression. DWI would thus seem to be of value in patients with PML.

Brain↗
PubMed2003

A prospective trial of mechanical physiotherapy for lumbar disk prolapse.

Fifty consecutive patients with neuroradiologically confirmed lumbar disk prolapse, who responded to the first five daily physiotherapy sessions with pain centralization, were prospectively treated with mechanical physiotherapy (McKenzie). At a median follow-up of 55 weeks, there were high rates of patient satisfaction, recovery from neurological deficits, and employment, and a low rate of surgical interventions. Mechanical physiotherapy is thus a useful diagnostic tool and an effective treatment strategy for many patients with lumbar disk disease.

Adolescent↗
PubMed2003

Detection of acute thalamo-mesencephalic infarction: diffusion abnormality precedes T2 hyperintensity.

OBJECTIVE: To examine the time course of signal changes in diffusion-weighted magnetic resonance imaging (DW-MRI) and T2-weighted MRI in a case of cerebral infarction in the posterior circulation territory. MATERIALS AND METHODS: Diffusion- and T2-weighted MRI and comparison of signal changes in these sequences at 4 h, 1 day and 4 days after the onset of clinical symptoms caused by acute thalamo-mesencephalic infarction. RESULTS: Four hours after the onset of symptoms, signal changes in DW-MRI revealed an infarction in the territory of the posterior perforating thalamic artery, whereas no signal changes were detected in T2-weighted MRI. In follow-up MRI 1 and 4 days after infarction, however, a marked hyperintensity matching the location of the diffusion deficit could be identified in T2 images. CONCLUSION: Signal changes in DW-MRI precede T2 hyperintensity after infarction in the posterior circulation territory after hemispheric infarction.

Acute Disease↗
PubMed2003

Isolated internal cerebral venous thrombosis in a neonate with increased lipoprotein (a) level: diagnostic and therapeutic considerations.

Background. Internal cerebral venous thrombosis is a life-threatening condition, which requires immediate therapy. Being infrequent in childhood, internal venous thrombosis is very rare in the neonate and has never been observed without concomitant occlusion of further dural sinuses. Case Description. We report a neonate born at term, who developed seizures on the third day of life after normal pregnancy and uneventful delivery. Ultrasound and CT disclosed bilateral intraventricular and intracerebral hemorrhage with an unusual distribution for germinal matrix hemorrhage. MRI disclosed thrombotic occlusion of the straight sinus and the internal cerebral veins with concomitant bleeding into the ventricles, the basal ganglia, thalamus and the periventricular hemispheres. The other sinuses were not affected. The clinical condition of the child improved after initiation of a low-dose heparin treatment with subsequent partial recanalization of the occluded vessels. The screening for risk factors disclosed an elevated lipoprotein (a) level, also present in both parents. Conclusion. Internal cerebral venous thrombosis may be encountered in neonates and must be included in the list of differential diagnosis of perinatal intraventricular and intracerebral bleeding. MRI allows the diagnosis even in the absence of widespread dural sinus occlusion. Low dose heparin may be a therapeutic option in these cases. This is the first report of neonatal internal venous thrombosis due to hereditary lipoprotein (a) level elevation, which must be included in the list of possible predisposing conditions.

Humans↗
PubMed2003

[Enhanced MR-angiography (CE-MRA) of the supraaortic arteries: dose reduction with a contrast agent of high relaxivity (Gd-BOPTA)].

PURPOSE: Reducing the amount of contrast medium in contrast-enhanced MR-angiography (CE-MRA) of the cervical vessels could lead to considerable cost reduction. This study investigates whether the amount of contrast medium possessing high relaxivity can be reduced without loss of diagnostic information. MATERIALS AND METHODS: In a prospective study the supraaortic vessels of 40 patients were examined on a 1.5 T MR-system using 10 or 20 ml Gd-BOPTA (MultiHance). The examinations were evaluated by measurement of the signal increase in the common carotid arteries in 38 patients. Furthermore, CE-MRA was rated by two independent observers, who were blinded to the amount of contrast medium and degree of stenosis. Rating criteria were quality of arterial contrast and image impression. RESULTS: Signal increase in the carotid artery was identical for 10 and 20 ml Gd-BOPTA in 12 patients with optimal bolus timing (10 ml: 454 +/- 58; 20 ml: 458 +/- 63). Signal intensities were significantly lower for 10 ml when bolus timing was suboptimal (281 +/- 80 vs 353 +/- 65; p < 0.02). The quality of the CE-MRA using 10 and 20 ml Gd- BOPTA was rated as identical by the observers, and the amount of contrast medium used could not be deduced from the images. CONCLUSION: Image quality and signal values of the carotid arteries did not differ in CE-MRA performed with either 10 ml or 20 ml Gd-BOPTA (MultiHance) as long as the examination is adequate. Thus, cost reduction can be achieved with a reduced standard dose of 10 ml Gd-BOPTA without loss of diagnostic information.

Aged↗
PubMed2002

Malformations of the midline commissures: MRI findings in different forms of callosal dysgenesis.

Malformations of the corpus callosum (CC) may occur in many different syndromes. Various forms have been observed. We report seven cases of malformation of the CC. Special attention is directed towards the development of the fornix and hippocampus as a hippocampal commissure is a prerequisite of normal hippocampal development. The clinical disability of the patients presented here differed significantly, which may in part be due to the different extent of this cerebral malformation. The relevance of the concomitant aplasia of the limbic system has not been addressed in detail previously in the literature.

Adult↗
PubMed2002

Primary central nervous system (CNS) lymphoma in immunocompetent patients.

Primary CNS lymphoma (PCNSL) has been increasing in incidence among both immunocompetent and immunocompromised patients. Today there is no uniform approach to the treatment of this disease. Whole brain irradiation (WBI) has been standard treatment, resulting in complete remission in the majority of patients, but with most patients relapsing and dying of their disease within 2 years after treatment. The addition of chemotherapy to WBI appears to prolong survival for patients younger than 60 years with median survival reaching a plateau at approximately 40 months. The issue of the best treatment for older patients remains controversial. Prospective studies will be needed, as it is impossible to draw conclusions from the nonrandomized small series published so far. This is because the prognostic variables of age and performance status to date have affected outcome more than therapy. In this review, some of the questions regarding the management of PCNSL are addressed. Since the role of radiotherapy remains unclear, we designed a new randomized multicenter study (G-PCNSL-SG-1 trial) to investigate the optimal timing of WBI after high-dose methotrexate (HD-MTX) chemotherapy.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2002

Primary CNS lymphoma in the spinal cord: clinical manifestations may precede MRI detectability.

We report a 36-year-old woman whose first MRI after developing symptoms of cervical nerve root irritation was normal. Eight months later, after progression to tetraparesis and demonstration of an extensive contrast-enhancing intramedullary lesion giving high signal on T2-weighted images, the diagnosis of lymphoblastic non-Hodgkin's lymphoma was made by biopsy. The lesion responded for a short time to corticosteroid medication, but later rapidly extended to the epidural soft tissues, probably due to a cerebrospinal fluid fistula. Despite radio-and chemotherapy, the patient survived only 7 months from histological diagnosis and 15 months from the onset of symptoms.

Adult↗
PubMed2002

Ocular manifestation of primary nervous system lymphoma: what can be expected from imaging?

Primary ocular lymphoma, which affects the posterior parts of the eye, is an ocular manifestation of primary central nervous system lymphoma (PCNSL). It used to be the ocular disease with the shortest time of survival, even worse than ocular melanoma. Death ensues by CNS dissemination. Unfortunately, ocular lymphoma may be the initial manifestation of PCNSL and diagnosis is frequently difficult, even if vitreal biopsy is performed. Therefore, it should be determined whether cross sectional imaging may be helpful in detection and differential diagnosis of ocular lymphoma. MRI of seven patients (female = 6, male = 1, median age 62 years) with biopsy proven ocular lymphoma were retrieved from the files of our hospital and of a multicenter PCNSL study. In four patients, ocular lymphoma was the first manifestation of PCNSL, in three a cerebral lesion had occurred in the first place. Progression to cerebral lymphoma was seen in three of the four patients with initial eye manifestation. Imaging was performed using a dedicated thin section protocol in four patients. An intraocular abnormality was found in four cases, always in T1-weighted images after contrast injection. Differential diagnosis from uveitis or ocular melanoma was not possible by imaging alone. The examination was falsely negative in the remaining three patients.Hence, imaging has a low sensitivity for ocular lymphoma and does not facilitate differential diagnosis against uveitis or ocular melanoma.

Aged↗
PubMed2002

Myelopathy in primary Sjögren's syndrome: diagnostic and therapeutic aspects.

We report a patient with a myelopathy in primary Sjögren's syndrome, proven by salivary gland biopsy and specific antibodies. Under steroid medication, the patient had a remitting and relapsing clinical course. The severity of clinical symptoms correlated with a transient contrast uptake in spinal magnetic resonance imaging. Under a treatment with azathioprine and prednisone the patient has suffered no relapse within the last 20 months. Although this is only a case report, the combination of azathioprine and prednisone may be a valuable medication in chronic cases of Sjögren's syndrome with neurologic symptoms.

Aged↗
PubMed2001

MRI features of primary, secondary and metastatic medulloblastoma.

Medulloblastoma is the most frequent paediatric malignant brain tumour. The purpose of this study was to define imaging characteristics and contrast uptake patterns of primary and recurrent medulloblastoma using MRI. The MRI examinations of 17 histologically proven cases of medulloblastoma diagnosed in our institution (13 males and 4 females; mean age 13 years, 7 months) were reviewed in retrospect. Only patients with pre-treatment and follow-up examinations including T2-weighted images (fluid-attenuated inversion recovery or turbo spin echo) and T1-weighted images after contrast injection (0.1 mmol/kg Gd-DTPA) were included in this study. Whereas 6 of 7 tumours ( n=17) were hyperintense on T2-weighted images, contrast enhancement was detected in 13 patients. Fifteen tumours occurred in the cerebellar vermis, two were located in the cerebellar hemispheres. Mean size at the time of presentation was 30.1 mm. All patients presented with some extent of an occlusive hydrocephalus. Local recurrent tumour or metastases were seen in 6 patients (3 months to 7 years, mean age 2.5 years). Whereas the T2 signal intensity of recurrent tumour or subarachnoidal metastases resembled the primary neoplasms, the contrast uptake tended to be less pronounced ( n=3) or was completely absent ( n=2); thus, suggestive signs of primary medulloblastoma are location in the vermis, hyperintensity on T2-weighted images and hydrocephalus. The amount of contrast enhancement is variable and nonspecific. Secondary medulloblastoma manifestation is characterized by T2 hyperintensity but not by contrast uptake.

Adolescent↗
PubMed2001

MRI features of primary central nervous system lymphomas at presentation.

Pretreatment MRI examinations of 40 immunologically competent patients with primary CNS lymphoma (PCNSL) were evaluated (24 men, 16 women, median age 63 years). Seventy lesions were found (mean size: 19.9 mm). The number of lesions ranged from one (n = 25) to six (n = 1). The most frequent locations were the cerebral hemispheres (n = 22), the corpus callosum (n = 11), and the basal ganglia (n = 11). Cerebellar manifestations were found in 10 patients. Ocular (n = 2) and medullary cord (n = 1) manifestations were rare. Contrast enhancement was encountered in all lesions. Although 39 patients had lesions adjacent to the CSF space, leptomeningeal spread was only present in five patients. Necrosis was seen in two lesions only. Edema was extensive in 24 patients, moderate in 11 patients, and absent in five patients. Contrast-enhancing lesions in contact with the subarachnoid space and without necrosis are characteristic of PCNSL.

Adult↗