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Biomedical subjects

E Klemm

Publications and source records attributed to E Klemm.

At least 37 records · Page 2Linked to original sources
PubMed1998

Inhibitory effects of mesial temporal partial seizures onto frontal neocortical structures.

PURPOSE: A retrospective evaluation of the ictal temporal tracer uptake and the perfusion pattern in other neo- and subcortical structures was performed to define typical extratemporal changes of rCBF that might further aid the differentiation of temporal and extratemporal seizures. METHOD: Ictal and interictal rCBF brain SPECT studies were done in 17 patients with seizures of mesial temporal onset according to scalp electroencephalography (EEG) and electrocorticography (ECoG) using 99mTc-ECD. Except for hippocampal sclerosis/atrophy, which was found in 11/17 patients, no morphologic anomalies were detected by MRI. Ictal tracer injections were given immediately after the onset of the seizure according to continuous video-EEG monitoring. The injection latency was two to twenty seconds. The data acquisition was done 45 minutes after the tracer injection using an annular crystal system (Ceraspect, DSI). In 15 patients a semiquantitative ROI-analysis of the tracer uptake in temporal and frontal regions could be obtained. RESULTS: All ictal studies correctly localised the affected temporal lobe. A detection of the epileptogenic focus itself was successful in 59% of patients while in the remaining patients the maximum of tracer uptake was not found to be located in the mesial temporal lobe only. In contrast to all other cerebral structures, only within the ipsilateral basal frontal cortex a frequent reaction to the temporal seizure was found. The basal frontal cortex ipsilateral to the affected temporal lobe showed a reduction of tracer uptake between the ictal and interictal study in 82% of patients which was semiquantitatively significant using a paired t-test (p < 0.05). Other neo- or subcortical structures showed inconsistent results. CONCLUSION: Secondary involvement of neocortical temporal structures in ictal rCBF-SPECT with 99mTc-ECD occurs early and focal maxima of tracer uptake within the temporal lobe do not necessarily represent the epileptogenic focus itself. Seizures of mesial temporal origin did not activate but frequently depressed the ipsilateral basal frontal tracer uptake during the early ictal phase. This phenomenon may account for some aspects of the clinical appearance of mesial temporal seizures.

Adolescent↗
PubMed1996

Temporal lobe dysfunction and correlation of regional cerebral blood flow abnormalities with psychopathology in schizophrenia and major depression--a study with single photon emission computed tomography.

Studies of regional cerebral blood flow in both schizophrenic and depressed patients have yielded contradictory findings. Single photon emission computed tomography (SPECT) was used to compare brain-perfusion patterns in 17 patients with schizophrenia and 12 patients with major depression and to evaluate the relationship of the findings to psychopathology. The images were analyzed both visually and quantitatively. Twelve of the 17 schizophrenic patients and 8 of the 12 depressed patients showed a pathological blood flow pattern. Hypoperfusion of the left temporal lobe was observed in seven of the schizophrenic and five of the depressed patients. Five of the schizophrenic patients also had a hypoperfusion of the left frontal lobe. Separation of both diagnostic cohorts in two subgroups with pathological and normal cerebral blood flow patterns revealed significantly higher levels of symptomatology in the group with hypoperfusion in the SPECT image. The analysis of different cerebral regions revealed statistically significant temporal hypoperfusion was significantly related to positive symptoms in schizophrenia. Our data suggest that left-sided temporal lobe dysfunction is related both to schizophrenia and major depression. The localization of hypoperfusion seems to be associated with the type of psychopathology (positive vs. negative symptoms in schizophrenia). Thus, the results support the model of paralimbic and prefrontal dysfunction in both diseases.

Adolescent↗
PubMed1996

Fluorine-18 fluorodeoxyglucose positron emission tomography in the follow-up of differentiated thyroid cancer.

Whole-body fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging was performed during the follow-up of 33 patients suffering from differentiated thyroid cancer. Among them there were 26 patients with papillary and seven with follicular tumours. Primary tumour stage (pT) was pT1 in six cases, pT2 in eight cases, pT3 in three cases and pT4 in 14 cases. FDG PET was normal in 18 patients. In three patients a slightly increased metabolism was observed in the thyroid bed, assumed to be related to remnant tissue. In one case local recurrence, in ten cases lymph node metastases (one false-positive, caused by sarcoidosis) and in three cases distant metastases were found with FDG PET. In comparison with whole-body scintigraphy using iodine-131 (WBS) there were a lot of discrepancies in imaging results. Whereas three patients had distant metastases (proven with 131I) and a negative FDG PET, in four cases 131I-negative lymph node metastases were detectable with PET. Even in the patients with concordant "staging", differences between 131I and FDG were observed as to the exact lesion localization. Therefore, a coexistence of 131I-positive/FDG-negative, 131I-negative/FDG-positive and 131I-positive/FDG-positive malignant tissue can be assumed in these patients. A higher correlation of FDG PET was observed with hexakis (2-methoxyisobutylisonitrile) technetium-99m (I) (MIBI) scintigraphy (performed in 20 cases) than with WBS. In highly differentiated tumours 131I scintigraphy had a high sensitivity, whereas in poorly differentiated carcinomas FDG PET was superior. The clinical use of FDG PET can be recommended in all cases of suspected or proven recurrence and/or metastases of differentiated thyroid cancer and is particularly useful in cases with elevated serum thyroglobulin levels and negative WBS.

Adult↗
PubMed1996

Interventional brain SPECT--a review.

Brain SPECT with HMPAO or ECD has-due to its short accumulation period--a rather high time resolution of approx 60 sec. Compared to isopropyl amphetamine (I-123) and FDG-PET, shortlasting interventions may be evaluated by SPECT. Usually, a two-step approach is used, injecting one third of the dose under baseline conditions and two thirds during intervention. The first study is then subtracted from the second study, resulting in a "difference" image which allows to calculate the effect of the intervention. These interventional procedures may include drug, mechanical, and mental intervention as well as ictal, blood pressure and receptor intervention. Moreover, the difference of pCO2 after hyperventilation or hypoventilation may also be used as a stimulus. The above mentioned procedures are described in detail.

Brain↗
PubMed1996

[Measuring basilar artery blood flow velocity with transcranial Doppler and and transcranial Doppler color ultrasound].

GOAL: The aim of the present study was to clarify, by means of transcranial colour-coded duplex sonography of the basilar artery, whether there are changes in basilar artery blood flow in patients with acute inner ear disturbances and whether the flow in the basilar artery is affected by acoustic stimuli in such patients and in normal, healthy controls. METHOD: Basilar artery blood flow velocity was measured in 52 patients with severe inner ear impairment over a period of two weeks by means of conventional transcranial Doppler sonography and transcranial colour-coded duplex sonography. The same measurements were carried out in 45 healthy control subjects. At the end of the two week period, both patients and controls were exposed to 70-dB noise, with basilar artery flow evaluated before and during exposure. The basilar artery Doppler curves were analysed for systolic flow velocity, end-diastolic flow velocity, resistance index (Pourcelot) and pulsatility index (Gosling). RESULTS: During the first two days of the study, the basilar artery resistance index and pulsatility index were significantly (p < 0.001) higher in patients than in controls. During noise exposure, both patients and controls showed significant (p < 0.01) increases in these indices. CONCLUSION: This study shows that temporary increases in the basilar artery resistance index and pulsatility index are found both in the acute phase of inner ear disease and during exposure to noise.

Acoustic Stimulation↗
PubMed1996

[123I]IBZM SPECT for imaging of striatal D2 dopamine receptors in 56 schizophrenic patients taking various neuroleptics.

OBJECTIVE: The purpose of this study was to compare the binding of various typical and atypical neuroleptics to striatal D2 dopamine receptors in schizophrenic patients. METHOD: Fifty-six inpatients with schizophrenia, including 14 with schizoaffective disorder and one with schizophreniform disorder, were evaluated. Fourteen patients were neuroleptic free. Single photon emission computed tomography (SPECT) was performed 90 minutes after intravenous injection of [123I]benzamide ([123I]IBZM). Subsequent semiquantitative analysis of D2 receptor binding was done with the use of the basal ganglia (striatum)/frontal cortex (BG/FC) ratio of activity. Clinical symptoms were rated with the Positive and Negative Syndrome Scale and the Hamilton Depression Rating Scale. RESULTS: The BG/FC ratios in patients taking typical neuroleptics were significantly lower than those in the neuroleptic-free subjects but not lower than those in the patients taking atypical neuroleptics (clozapine, remoxipride). For atypical antipsychotics, a dose-dependent relationship with striatal D2 receptor binding could not be demonstrated. BG/FC ratios were not significantly correlated with clinical symptoms or with duration of illness. CONCLUSIONS: The results indicate that [123I]IBZM SPECT is useful for semiquantitative imaging of striatal D2 dopamine receptors and for estimating their blockade by neuroleptics. Thus, it may improve drug monitoring in psychiatric patients. Furthermore, the findings suggest a complex relationship between the antipsychotic effect of atypical neuroleptics and D2 receptor blockade.

Adult↗
PubMed1995

[Color-coded duplex ultrasound findings and transcranial color duplex ultrasound findings in patients with acute inner ear disorders--a preliminary observation].

A prospective investigation of 98 patients with acute loss of inner ear function showed that such patients display changes in the pulsatility of the basilar artery; however, the differences can be appreciated only by comparison with control sonograms during the course of the disease. Patients with sudden deafness or sudden loss of equilibrium generally showed unremarkable findings on duplex sonography of the cervical portions of vessels supplying the brain.

Acute Disease↗
PubMed1993

[Brain SPECT with 123I-labelled iodobenzamide (IBZM): aspects of semiquantitative evaluation].

The striatal dopamine-D2-receptor uptake of 123I-IBZM in 32 patients (18 without and 14 under therapy with typical neuroleptics) was measured semiquantitatively using different ROI techniques. The aim of the study was to evaluate the influence of these techniques on the different ratios (striatum/cortex) found by various examiners. Using the same SPECT system no major differences were found between rectangular and manually drawn ROIs of the same size. All ROI techniques could differentiate between patients with and without therapy on a highly significant level. Therefore, the resulting ratio is mainly dependent on the spatial resolution of the camera system and only to a relatively minor extent on the ROI technique. Ratios obtained by different observers are not comparable quantitatively.

Adult↗
PubMed1993

[HMPAO-SPECT in Alzheimer-type dementia and major depression with memory disorders].

The aim of the present study was to see whether HMPAO-SPECT may contribute to the differentiation between dementia of the Alzheimer type (DAT) and major depression (MD). The results in 77 patients with memory impairment were evaluated. 48 patients suffered from DAT and 29 from MD. Initially, the defects in SPECT imaging were attributed to a cerebral region and the degree of decrease was evaluated (-1/-2/-3). Thereafter, the results were classified by 7 categories. In some of these categories an accumulation of cases of either DAT or MD was found. 35% of the patients suffering from DAT had bilateral defects with distinct (> -1) parietal/parietotemporal hypoperfusions, but no patient with MD showed this perfusion pattern. 62% of the patients with MD had unilateral defects but only 31% of the patients with DAT. The present study demonstrates that only 35% of all patients suffering from DAT show a perfusion pattern, thought earlier as "pathognomonic" for this disease. This perfusion pattern--if it exists--may be used as a safe criterion to exclude MD. Beyond that no clearcut ("specific") perfusion pattern may be recognized but unilateral defects point to MD.

Aged↗
PubMed1993

[Aggressive episodes without amnesia. Differential diagnostic problems based on a case report].

A 21-year-old patient suffered from recurrent attacks characterized by aggression and a varying disturbance of consciousness. He had no amnesia for these episodes. Loss of activity and social withdrawal had heralded the manifestation of the disease. He had delusions at times. The problems of differential diagnosis: schizophrenic disorder, frontal lobe epilepsy, or psychogenic seizures are discussed.

Adult↗
PubMed1991

[Familial spastic spinal paralysis--clinical spectrum and differential diagnostic considerations].

The familial spastic paraplegia is a rare disorder of the cerebral nervous system characterized by a slowly progressive spasticity of the lower limbs with early or late onset. There are pure and complicated forms. The disease is inherited by an autosomal dominant mode and a recessive one. In this study 6 patients out of 5 families are presented. The clinical variety, genetic aspects, electrophysiological results and differential diagnosis are discussed.

Adult↗
PubMed1991

[Sudden deafness. A clinical analysis with special reference to tympanoscopy].

From a total of 720 patients with acute deafness, 85 patients suffered from unilateral deafness with a hearing loss of at least 80 dB in the speech frequency range. Under conservative therapy in 58 patients, there was an improvement in hearing in 19 cases and a return to normal in 6 patients. In 27 patients, the clinical history was suggestive of a possible tympanic membrane rupture, which was confirmed by tympanoscopy in 5 cases. On 5 other occasions, the intraoperative findings were highly suggestive of tympanic membrane rupture. In each case, a membranoplasty was performed. The results of operative therapy tended to give better results than conservative therapy. The presence of concomitant vestibular disorders did not influence the results of treatment in either group. The results of the study show, that apart from tympanoscopy, there are no other diagnostic criteria to recognize a membrane rupture. Typical case histories demonstrate that tympanoscopy can be useful diagnostic and therapeutic measure in cases of therapy-resistant deafness.

Adolescent↗
PubMed1990

Isolation and characterization of HIV-2ben obtained from a patient with predominantly neurological defects.

A HIV-2 strain named HIV-2ben was isolated from peripheral blood lymphocytes of a patient who, since 1984, had developed neurological symptoms such as Raynaud's syndrome, followed by paresthesia of extremities and ataxia, and finally paraparesis of the legs and incontinence. This new isolate could be distinguished from HIV-2rod by antibody-binding epitopes, peptide maps of core p24 and p18 polypeptides and restriction endonuclease cleavage pattern.

Animals↗
PubMed1989

Adult-onset metachromatic leucodystrophy presenting without psychiatric symptoms.

A 24-year-old man presented with a spastic and ataxic condition resembling chronic-progressive multiple sclerosis. Radiological examination revealed symmetrical diffuse paraventricular demyelination. Electrophysiological findings suggested additional involvement of the brain stem and the peripheral nervous system. The diagnosis of adult-onset metachromatic leucodystrophy was confirmed by biochemical and ultrastructural examination. In contrast to almost all adult cases reported so far, psychiatric symptoms were not present.

Adult↗
PubMed1988

HIV-II infection with initial neurological manifestation.

A patient with positive serological HIV-II reactions is presented, who lived for many years in North and West Africa and on the Arabian peninsula, and who developed asthenica, incontinence, gait disturbances, impaired mental function, personality changes and finally spastic paraplegia and peripheral neuropathy. He was shown to have a chronic inflammatory process of the central nervous system with cerebral atrophy.

Acquired Immunodeficiency Syndrome↗