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L Solymosi

Publications and source records attributed to L Solymosi.

At least 19 recordsLinked to original sources
PubMed1995

A characteristic ventricular shape in myelomeningocele-associated hydrocephalus? A CT stereology study.

We measured the volume of the supratentorial ventricles in 39 consecutive children with myelomeningocele (MMC) and associated hydrocephalus, using a stereological method based on the Cavalieri theorem of systematic sampling. We distinguished the following groups: newborns before and after cerebrospinal fluid shunting (14), a somewhat larger group of newborns with an untreated MMC-associated hydrocephalus (25) and a group of shunted children at a mean age of 1.5 years (28). We paid special attention to the shape of the lateral ventricles, looking separately at the anterior and posterior halves. The measurements were compared with a healthy control group (10) and with children with hydrocephalus unrelated to MMC (15). The average volume ratio of the posterior to the anterior half of the lateral ventricles was 1.05 +/- 0.39 in non-hydrocephalic children, 1.11 +/- 0.55 in untreated hydrocephalic children without MMC, and 2.15 +/- 0.65 in MMC-associated hydrocephalus prior to shunting. These ratios did not change significantly after shunting. This confirms our impression that MMC-associated hydrocephalus shows a characteristic shape, with a disproportionate enlargement of the posterior part of the lateral ventricles, in clear contrast to the normal-width frontal horns. This shape is reminiscent of the fetal ventricular shape. It reveals disturbance of brain development in children with MMC, which goes beyond the classic description of the Chiari malformation.

Arnold-Chiari Malformation↗
PubMed1995

Posterior inferior cerebellar artery aneurysm in the fourth ventricle.

We report a patient with a ruptured aneurysm of the choroidal branch of the right posterior inferior cerebellar artery (PICA), lying in and causing an isolated haemorrhage in the fourth ventricle. MRI on the first day after bleeding revealed an abnormal vessel in the fourth ventricle, which was surrounded by a mass of intermediate signal on T1- and T2-weighted images. The aneurysm was clipped via partial splitting of the lower vermis and opening the inferior medullary velum. A postoperative angiogram confirmed complete obliteration of the aneurysm. With PICA aneurysms the rate of intraventricular haemorrhage is high and in most cases due to reflux of blood. If there is an isolated intraventricular haemorrhage, a peripheral PICA aneurysm, lying in or near the fourth ventricle, may be suspected.

Cerebellum↗
PubMed1995

[Multimodal carotid occlusion test for determining risk of infarct before therapeutic internal carotid artery occlusion].

UNLABELLED: In patients with head and neck carcinoma and extensive cervical metastasis, the topographic and functional relationship of the tumor to the carotid artery is highly important. In case of suspected carotid infiltration, the possibility of a carotid resection or a prosthetic replacement has to be considered preoperatively. Treatment of cavernous carotid aneurysms may also require sacrificing the internal carotid artery (ICA). An interdisciplinary test occlusion of the ICA was performed to assess cerebral collateral circulation prior to permanent carotid occlusion. MATERIALS AND METHODS: Fifty-two patients with cervical tumors (n = 45) or inoperable aneurysms (n = 7) were examined. The endovascular balloon test occlusion (BTO) of the ICA was combined with monitoring of the neurological status, cardiovascular status (EKG, blood pressure), cortical function (EEG), and single photon emission CT (SPECT) imaging of the regional cerebral blood flow (rCBF) with 99mTechnetium-HMPAO. In the last 24 patients, transcranial Doppler sonography (TCD) of the ipsilateral middle cerebral artery (MCA) was added for direct hemodynamic monitoring during BTO. In order to improve the diagnostic value of the test results and to simulate hemodynamic crisis, the cerebrovascular reserve capacity was then evaluated with acetazolamide (Diamox). RESULTS: BTO could be performed without neurological complications or carotid dissection. In eight (15%) patients BTO had to be interrupted previously due to neurological symptoms or a delta-EEG. These patients and patients with highly pathological test results in SPECT imaging (n = 9) or TCD (n = 3) were excluded from permanent carotid occlusion. Ten (19%) patients were definitely occluded without hemodynamic complications, but two patients suffered embolic infarctions, which can not be predicted by this procedure. In two patients with a severe hypoperfusion in SPECT imaging, the ICA had to be ligated under emergency conditions following a carotid rupture. Predictably, a hemodynamic infarction occurred postoperatively in both patients. CONCLUSIONS: The multimodal BTO with brain perfusion imaging (HMPAO-SPECT) and quantitative blood flow monitoring (TCD) allows a hemodynamic stroke risk assessment prior to permanent occlusion of the ICA. The procedure is important for planning of the therapeutic strategy and for the preoperative dialogue with the patient. Embolic ischemic complications can not be predicted.

Adult↗
PubMed1995

Surgical treatment of temporal lobe epilepsy: clinical, radiological, and histopathological findings in 178 patients.

The surgical treatment of pharmacoresistant temporal lobe epilepsy is increasing rapidly. The correlation of preoperative MRI, histopathological findings, and postoperative seizure control is reported for 178 patients with chronic medically intractable temporal lobe epilepsy who were operated on between November 1987 and January 1993. Histopathologically there were distinct structural abnormalities in 97.2% of the surgical specimens. Signal abnormalities on MRI were present in 98.7% of patients with neoplastic lesions (n = 79), 76.6% of patients with non-neoplastic focal lesions (n = 55), and 69.2% of patients with Ammon's horn sclerosis (n = 39). Overall, structural abnormalities were detected by MRI in 82.7% of all patients. The mean postoperative follow up period was three years. Some 92% of the patients benefited from surgery: 103 patients (61.7%) were seizure free, 26 (15.5%) had no more than two seizures a year, and 24 (14.4%) showed a reduction of seizure frequency of at least 75%. Fourteen patients (8.4%) had a < 75% reduction of seizure frequency. The percentage of patients who were completely free of seizures after operation was 68.5% for patients with neoplastic lesions, 66.7% for Ammon's horn sclerosis, and 54.0% for patients with non-neoplastic focal lesions. By contrast, none of the patients in whom histopathological findings were normal became seizure free postoperatively. The data show that the presence of focal lesions or Ammon's horn sclerosis as determined by histopathological examination is associated with improved postoperative seizure control compared with patients without specific pathological findings. Brain MRI was very sensitive in detecting neoplasms; however, its sensitivity and specificity were limited with respect to non-neoplastic focal lesions and Ammon's horn sclerosis. Improvement of imaging techniques may provide a more precise definition of structural lesions in these cases and facilitate limited surgical resections of the epileptogenic area rather than standardised anatomical resections.

Adolescent↗
PubMed1995

[Embolization of bone metastases].

Eighteen patients (11 renal tumours, 3 bronchogenic carcinomas, 4 others) with 24 different bone metastases were embolized for preoperative devascularization (11 x) or for intractable pain (7 x). Metastases were localized in the spine (17 x), pelvis (5 x), and shoulder girdle (2 x). All metastases were hypervascularized. Post-embolization showed no complications. Intraoperative blood loss was minimized to 2100 ml (600 ml-4200 ml). Pain relief was achieved in 6 out of 7 patients. Eight of 18 patients died as a result of underlying diseases (follow-up 7 months).

Aged↗
PubMed1994

[The value of MR tomography after transsphenoidal hypophyseal resection. A retrospective comparison between endocrinology, operation and MRT].

Postoperative magnetic resonance images of 40 patients after transsphenoidal surgery for pituitary adenoma were evaluated retrospectively. The signal intensities of packing material and residual tumour were analysed. T1-weighted spin-echo sequences were obtained in coronal and sagittal views with and without intravenous injection of contrast media. Residual tumour demonstrated homogeneous or inhomogeneous signal intensity on the native scan with homogeneous or inhomogeneous enhancement. Packing material demonstrated a homogeneous signal intensity on the images obtained without injection of contrast media with a peripheral enhancement or alternate layers of low and intermediate signal intensity with alternate enhancement after injection of contrast media. In 5 of 54 examinations different results were found in MRI, endocrinology and surgery (two false negative and one false positive MRI in correlation with endocrinology; two residual tumours on MRI where surgery was supposed to be complete). Application of intravenous contrast media facilitates the interpretation of postoperative examination of the pituitary gland as well as comparison with preoperative examinations and the knowledge of the intraoperative procedure.

Adenoma↗
PubMed1994

Gangliogliomas: clinical, radiological, and histopathological findings in 51 patients.

Clinical, radiological, and histopathological features of 51 surgically treated gangliogliomas were evaluated retrospectively. The most common presenting symptoms were epileptic seizures (47 patients (92%)). Focal neurological deficits occurred in 8% of the patients. The duration of symptoms at the time of operation ranged from three months to 45 years, mean 11 years. The temporal lobe was affected in 43 patients (84%), the frontal lobe in five patients (10%), and the occipital lobe in one patient (2%). Two of the tumours (4%) were localised infratentorially. On MRI, solid tumour parts usually showed a pronounced signal increase on proton density images and a less pronounced signal increase on T2 weighted images, whereas solid components were mainly isointense on T1 weighted images. Contrast enhancement was noted in 16 of 36 patients (44%). Cystic tumour parts were found in 23 of 40 patients (57%), all characterised by signal increase on T2 weighted images and decreased T1 signals. Signal deviation of cystic tumour parts on proton density images was variable. Computed tomography was performed in 17 patients and showed hypodense lesions in 10 (59%), and calcifications in seven (41%) cases. Surgery included complete tumour removal in 44 patients (86%) and partial resection in seven (14%). In six patients (12%) there were transient postoperative complications. One patient (2%) died postoperatively due to pulmonary embolism. Histopathological examination of the surgical specimens showed low grade gangliogliomas in 49 cases (96%) and anaplastic gangliogliomas in two (4%). Control MRI of 31 patients with a mean follow up period of 16 months was uneventful in all but one case of an anaplastic ganglioglioma. In all patients in whom the ganglioglioma was associated with medically intractable seizures the operation resulted in complete relief of seizures or a noticeable improvement of the epilepsy.

Adolescent↗
PubMed1994

Cerebral MR in ophthalmoplegia plus.

PURPOSE: To evaluate MR patterns in ophthalmoplegia plus and correlate them with clinical symptoms. METHODS: MR was performed on a 1.5-T whole-body scanner with T2-weighted gradient-echo and spin-echo images. The retrospective analysis included 19 patients with clinically established diagnoses of ophthalmoplegia plus. RESULTS: Two types of cerebral MR abnormalities were found in ophthalmoplegia plus: brain atrophy and hyperintensities restricted to the white matter and basal ganglia, which appeared as either focal or diffuse areas of high signal intensity and were of strictly supratentorial location. No specific distribution was found. These findings differ markedly from infarction-like lesions found in mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes. CONCLUSIONS: MR is sensitive for the detection of central nervous system involvement in ophthalmoplegia plus, but findings are nonspecific. However, cerebral MR in ophthalmoplegia plus is different from other mitochondrial encephalomyopathies and underlines the clinical differentiation of mitochondrial encephalomyopathies.

Adolescent↗
PubMed1993

Magnetic resonance angiography of cerebral developmental venous anomalies: its role in differential diagnosis.

CT, MRI and contrast angiography of 20 patients with 21 developmental venous anomalies (DVAs), so-called venous angiomas, were compared with magnetic resonance angiography employing a two-dimensional time-of-flight technique (2D-MRA). MRA was diagnostic in 17 DVAs, when both the primary 2D slices and the maximum-intensity-projection images were read. Contrast angiography still provides the best visualization of both DVA components: dilated medullary veins and transcerebral draining vein; however, it is an invasive procedure and delivers no information about brain parenchyma. We regard MRI as necessary in cases with a suspected DVA because of the high rate of association with cavernomas: 33% in this study. Acute neurological symptoms were caused by haemorrhage from an associated cavernoma and not from the DVA in 4 such cases. Thus MRA combined with MRI obviates angiography in most cases and offers a noninvasive diagnostic strategy adequate for DVAs.

Adolescent↗
PubMed1993

Differentiation of multi-infarct and Alzheimer dementia by intracranial hemodynamic parameters.

BACKGROUND AND PURPOSE: The differentiation between the Alzheimer and multi-infarct types of dementia may still be equivocal considering clinical criteria, neuropsychological tests, and imaging techniques. Cerebral microangiopathic alterations underlying multi-infarct dementia should allow the characterization of dementia subgroups. METHODS: Patients with a diagnosis of multi-infarct dementia (n = 17; mean age, 69.1 +/- 8.5 years) or Alzheimer dementia (n = 24, mean age, 65.8 +/- 9.0 years) according to standard testing criteria, clinical findings, and neuroimaging techniques (computed tomography and magnetic resonance imaging) were investigated prospectively by transcranial Doppler sonography and compared with a normal reference group (n = 64; mean age, 61.0 +/- 11.1 years). Transcranial Doppler sonography allows an indirect evaluation of peripheral flow resistance in the microcirculatory bed by quantifying pulsatility characteristics, as reflected in the effective pulsatility range (time-averaged mean blood flow velocity minus the peak-systolic to end-diastolic amplitude, in centimeters per second). RESULTS: A total of 204 vessels were investigated in 105 subjects. Mean and diastolic blood flow velocities as well as the effective pulsatility range were significantly lower in the multi-infarct dementia group compared with the Alzheimer and the normal reference groups (p < 0.001). By using receiver operating characteristic analysis, a cutoff point for effective pulsatility range values of -5 cm/sec gives a side-dependent sensitivity of 90.48-95.24% and a specificity of 64.71-70.59% in diagnosing Alzheimer-type dementia; the corresponding sensitivity and specificity for a value of -2 cm/sec are 82.35-88.24% and 80.95-90.48%, respectively. CONCLUSIONS: Pulsatility changes as reflected by the effective pulsatility range are a noninvasive additional criterion in the differential diagnosis of dementia.

Aged↗
PubMed1993

[Neuroradiologic methods and findings prior to the surgical treatment of epilepsy in children].

Epilepsy in childhood is often caused by morphological abnormalities and is frequently pharmacoresistant. Therefore it represents a challenge to the neuroradiologist because early and accurate diagnosis of abnormal morphology is the basis for planning surgical intervention with a high chance of controlling seizures and a low risk of complications. Both morphological (radiography, CT, MRI and angiography) and functional examinations [intracarotid amobarbital test (IAT)] are essential parts of the presurgical evaluation. In most cases MRI has proved to be most sensitive in detecting lesions except for some calcifications. Routine protocols for brain examinations are not sufficient, missing about 22% of lesions. Therefore a refined MRI and CT protocol is proposed. Even in very young children IAT can be performed at very low risk; these tests contribute highly valuable information about actual hemispheric dominance and other functions in more than 80% of procedures that is indispensable if postoperative neurological and neuropsychological deficits are to be avoided.

Adolescent↗
PubMed1993

[The intracarotid amobarbital test. Neuroradiologic and neuropsychologic aspects].

In presurgical evaluation of epilepsy, unilateral cerebral inactivation by means of intracarotid injection of amobarbital is used for the determination of cerebral dominance for language and memory functions. This intracarotid amobarbital test (IAT) is intended to yield prognoses concerning postsurgical neuropsychological and neurological deficits. In the present review, neuroradiological and neuropsychological aspects of the procedure are discussed. Each IAT is preceded by a cerebral angiography to exclude or detect vascular anomalies that might be relevant to the interpretation of neuropsychological test data. The main methodological problems of the IAT are interference of various cognitive deficits and monitoring of the course of amobarbital action. Alternative procedures of determination of hemispheric asymmetries--positron emission tomography, electrical stimulation mapping, and noninvasive methods like tachistoscopy--mainly yield data complementary to the results of the IAT and hence are not taken as substitutes of that technique.

Amobarbital↗
PubMed1993

[The selective amobarbital test in epileptology].

Epileptic foci in the frontal or parieto-occipital cortex often cause epileptiform EEG changes in both hemispheres. Therefore, delineation of the primary epileptogenic area, which is necessary for epilepsy surgery, is not possible by electrophysiological methods. A temporary inactivation of the epileptogenic area by a selective injection of the short-acting barbiturate amobarbital (selective amobarbital test, SAT) can prove the relation between generalized EEG changes and a circumscribed epileptogenic area. The SAT may also be used for evaluation of the risk for additional functional deficits after epilepsy surgery in certain brain areas. During temporary inactivation of the brain area to be resected, the function of the motor system, speech and memory can be tested.

Amobarbital↗
PubMed1992

Interhemispheric dissociation of expressive and receptive language functions in patients with complex-partial seizures: an amobarbital study.

Bilateral intracarotid amobarbital procedures (IAP) were performed in 144 patients with medically intractable complex-partial seizures. As a result of language testing, 29 patients (20.1%) were found to have bilateral language representation to different degrees. In four (2.8%) of these patients--all right-handers with early onset of epilepsy and/or evidence of early brain damage--there was strong evidence of an interhemispheric dissociation of expressive and receptive language functions. Two of these patients had circumscribed temporal foci (one left, one right), and receptive language functions were represented in the hemisphere contralateral to the focus. One patient with a right frontal focus showed left-hemisphere dominance for expressive functions, while the fourth patient exhibited left-hemisphere dominance for receptive functions associated with a right temporo-parietal focus. It is argued that in these four cases the circumscribed functional and/or structural impairments have led to a shift of the anatomically associated language functions to the opposite hemisphere (rather than to neighboring regions of the same hemisphere). These findings substantiate the hypothesis that in special circumstances the anterior (expressive) language area can be located in one hemisphere and the posterior (receptive) area in the other.

Adolescent↗
PubMed1990

Activation of the epileptic focus during intracarotid amobarbital test. Electrocorticographic registration via subdural electrodes.

During presurgical evaluation, bilateral intracarotid amobarbital tests were performed in 21 patients (42 tests) to establish the lateralization of cerebral speech dominance as well as memory function. All patients suffered from long-standing, medically intractable, complex partial seizures. Electrocorticographic recording during the investigation was carried out via bilaterally implanted subdural electrodes. The aim of the study was to assess amobarbital-induced effects on the primary epileptic focus, determined throughout presurgical evaluation. Following the application of amobarbital the primary epileptic focus was selectively activated in 10 and preferentially activated in 3 patients suffering from temporal lobe epilepsy. Specific responses of the primary epileptic focus consisted of: (i) induction of a spike-burst-suppression pattern, mainly in the mesio-basal aspects of the focal temporal lobe (n = 13); (ii) induction of spikes or sharp waves following contralateral intracarotid injection (n = 10); (iii) late induction of spikes or sharp waves following ipsilateral injection (n = 4); (iv) loss or marked reduction of drug-induced beta activity over the primary epileptic focus (n = 14) following ipsilateral or contralateral injection. In conclusion, electrocorticographic recording during the intracarotid amobarbital test contributes valuable information about the primary epileptic focus in a high proportion of patients.

Action Potentials↗
PubMed1990

[Concomitant vertebral trauma in patients with craniocerebral injuries. 34 consecutive patients over 3 years].

Between February 1986 and January 1989, a total of 430 inpatients with the diagnosis of a head injury were prospectively registered and analysed for the association of a spinal trauma. Of these patients, 92% (n = 396) suffered a primary coma and 8% (n = 34) a secondary coma. On admission the ratio of coma, somnolence, and mild clouding was 6:1:3. In 8% (n = 34) the head injury was combined with a lesion of the spinal column. The cervical spine was affected in two-thirds of the cases (21/34). The clinical outcome was subdivided into three categories: dead (n = 10), paraplegic (n = 12), and 12 other patients. At least 4 patients were disabled at the end of the observation period (hospitalized or receiving home care). It is discussed how to avoid overlooking associated spinal fractures in patients with head trauma and multiple injuries that all require emergency treatment.

Adolescent↗