Biomedical subjects

L Solymosi

Publications and source records attributed to L Solymosi.

At least 19 recordsLinked to original sources

PubMed2002

Sequential MRI and MR spectroscopy in embolized meningiomas: correlation with surgical and histopathological findings.

The preoperative embolization of meningiomas is commonly used to facilitate surgery. The purpose of this study was to evaluate the morphological and metabolic changes in embolized meningiomas and to correlate the results with surgical and histopathological findings. In a prospective study, 36 patients with intracranial meningiomas were included. The extent of devascularization was assessed by angiography and MR volumetry. MRI and MR spectroscopy (MRS) were performed before and sequentially after embolization. At surgery, blood loss was measured and intraoperative duplex-mode ultrasound was applied to identify avascular tumor portions. Histopathological specimens were evaluated for the histological subtype, localization and extent of necrotic tumor portions. Postembolization MRI revealed a variable pattern of secondary revascularization and devascularization with an early onset following embolization. In all patients, peripheral secondary enhancement was present which histopathologically represented a thin layer of vital tumor tissue. MRS revealed lactate in devascularized areas immediately after embolization. Lipids were not observed before the 3rd day after embolization and were always associated with avascular and soft tissue at the time of surgery. Embolized meningiomas feature a variable dynamic with the potential for revascularization and secondary devascularization. Lipid signals indicate avascular and soft tissue at surgery. In case of delayed surgery, MRI and MRS should be performed in order to exclude revascularization and to establish the fatty degeneration of the meningioma.

Embolization, Therapeutic↗

PubMed2001

Measurement of the midbrain diameter on routine magnetic resonance imaging: a simple and accurate method of differentiating between Parkinson disease and progressive supranuclear palsy.

Anteroposterior diameters of the suprapontine midbrain, the pons, and the collicular plate were measured in 50 patients with various parkinsonian syndromes (Parkinson disease [PD] [n = 20], progressive supranuclear palsy [PSP] [n = 16], and multiple-system atrophy of striatonigral type [n = 14]) and 12 age-matched healthy control subjects by means of axial T2-weighted magnetic resonance images. While no differences in midbrain diameter were found between patients with PD (mean, 18.5 mm) and control subjects (mean, 18.2 mm), patients with PSP had significantly lower midbrain diameters (mean, 13.4 mm) than patients with PD and control subjects (P<.001), without any overlap between these 2 groups. However, midbrain diameters of patients with multiple-system atrophy were also significantly lower than those of control subjects and patients with PD, with individual values showing overlap with the PSP, PD, and control groups. Pontine and collicular plate diameters did not contribute additional information. We therefore conclude that measurement of anteroposterior diameter of the midbrain on axial T2-weighted magnetic resonance images is a reliable means to differentiate patients with PSP from those with PD and should be incorporated into the diagnostic criteria for PSP.

Aged↗

PubMed2001

Diagnosing dural metastases: the value of 1H magnetic resonance spectroscopy.

The purpose of this study was to assess the value of MRI, MR spectroscopy (MRS) and intra-arterial angiography in the preoperative diagnosis of extra-axial dural-based masses. We prospectively studied 54 patients who underwent preoperative MRI, MRS and angiography. Histologically there were 50 meningiomas and four dural metastases. MRI and angiography did not allow reliable differentiation between meningiomas and metastases. MRS showed elevated choline/creatine ratios in both meningiomas and metastases, but there were prominent lipid signals in all metastases and a lactate peak in two. This spectroscopic pattern was not found in meningiomas. However, following embolisation, they showed similar spectra, due to ischaemia and necrosis. We therefore believe MRS to be valuable in differential diagnosis of dural metastases and meningiomas prior to embolisation.

Aged↗

PubMed2001

MRI in isolated sixth nerve palsies.

In previous studies the origin of the majority of isolated sixth nerve palsies was not clear or was ascribed to vascular disease. Our purpose was determine how frequently a causative lesion was demonstrated on MRI in patients with an acute unilateral sixth nerve palsy. We performed a prospective study of 43 patients using a standardised protocol. In 27 patients (63%) a lesion was identified on the initial MRI relevant to the sixth nerve palsy; 21 (49%) were found to have a tumour or tumour-like lesion; the frequency of presumed vasculopathy in this group was 15%. There were 16 patients (37%) with an initially normal MRI, of whom 10 (62%) had a history of vasculopathy, a significantly different proportion from the group of patients with a visible causative lesion. MRI after 3-6 months was normal in all patients with a normal initial MRI. We suggest that MRI should routinely be performed in patients presenting with an acute sixth nerve palsy, even those with evidence of a vasculopathy. If the symptoms regress spontaneously and there is a history of vasculopathy, follow-up MRI is not necessary.

Abducens Nerve↗

PubMed2001

Cerebral activation patterns in patients with writer's cramp: a functional magnetic resonance imaging study.

Functional MRI (fMRI), visualizing changes in cerebral blood oxygenation, has to date not been performed either in patients with writer's cramp or in healthy subjects during writing. We compared the cerebral and cerebellar activation pattern of 12 patients with writer's cramp during writing with a group of 10 healthy subjects performing the same tasks over 30-s periods of rest or writing. Sixty echo planar imaging multislice datasets were analysed using SPM96 software. Data were analysed for each subject individually and groupwise for patients vs. controls. Healthy subjects showed a significant activation of the ipsilateral dentate nucleus, contralateral cerebellar hemisphere, contralateral primary sensorimotor cortex, and contralateral precentral gyrus during writing. Patients with writer's cramp showed significantly greater activation of the ipsilateral cerebellar hemisphere than controls. Also the activation in the primary sensorimotor cortex extended further caudally and anteriorly towards the premotor association area. Activation was observed in the thalamus during writing only among the patients. Our results indicate an increased basal ganglia output via the thalamus to the motor and premotor cortical areas in dystonia patients and support the notion of disinhibition of the motor cortex leading to cocontractions and dystonic postures.

Adult↗

PubMed2001

A study of cranial computer tomograms in very early and early onset schizophrenia.

The cranial computer-assisted tomograms of 19 patients suffering from schizophrenic psychoses with onset by age of 14 were examined. The emphasis was on the extent of the inner liquor spaces. Compared to healthy controls, at the beginning of illness a significant enlargement was revealed only in the patient group with very early onset schizophrenia (VEOS, onset prior to the age of 12), whereas children with early onset (EOS, 12 to 14 years of age) showed no significant brain pathology. As a second result, an increase in the extent of the inner liquor spaces seems to correlate with the duration of illness. It is therefore concluded that psychoses interfere with neurodevelopmental processes and cause more severe brain pathology in very young children, already detectable at the onset of the illness. EOS, on the other hand, induces progressive morphological abnormalities over the course of the illness.

Adolescent↗

PubMed2001

Mechanical detachable platinum coil: report of the European phase II clinical trial in 60 patients.

PURPOSE: To determine the safety and reliability of the mechanical detachment system of a platinum coil (Detach-18) when used for neurovascular embolization. MATERIALS AND METHODS: Sixty patients (21 men, 39 women; age range, 26-75 years; mean age, 56.2 years) were treated in seven centers. Ease of introduction of the coil to the microcatheter, effect of coil passage on the microcatheter shape and stability during its delivery, retrievability of the coil before and after the transition zone passed beyond the microcatheter, detachment of the coil, and effect of coil rotation on the microcatheter stability were evaluated. The detachment system itself was evaluated for premature detachment, failure of the coil to detach, detachment time, number of turns, visibility of radiopaque markers, number of coils deployed per patient, and percentage of vessel occlusion obtained. A 0.015-inch-diameter regular coil and a 0.014-inch-diameter soft coil were used. RESULTS: A total of 1,061 coils were used; 1,009 were detached. The number of coils deployed ranged from four to 104 (mean, 17 coils). The coils passed easily through the microcatheter. The detachment maneuver occurred within 5-25 seconds, with five to 60 turns of the introducing wire. One premature coil detachment occurred without clinical sequela; 100% occlusion of the vessel lumen was achieved in 53 patients; 80%-90%, in four; and 70%-80%, in two. There were no device-related complications. CONCLUSION: The detachment system was safe and reliable. This is a useful system for coil embolization in neurovascular diseases.

Adult↗

PubMed2001

A report of the clinical use of the detach-18 mechanical detachable platinum coil in 41 patients.

BACKGROUND AND PURPOSE: The purpose of this study was to determine the safety and reliability of the mechanical detachment system of a new platinum coil, Detach-18, when used as a vascular occlusive device for neurovascular disease. METHODS: Forty-one patients (nine male and 32 female patients; age range, 26-75 years; mean age, 54.4 years) underwent treatment at seven centers. Twenty-two patients had dural arteriovenous fistulae of the transverse sinus treated by a transvenous route. Fourteen patients underwent internal carotid artery occlusion in the treatment of aneurysms, meningioma, facial tumor, or carotid injury. One patient underwent occlusion of the basilar artery and one patient underwent occlusion of the vertebral artery for treatment of aneurysms. In two patients, coils were used as part of the treatment of their arteriovenous malformations. In all cases, the Detach-18 coils were delivered through a microcatheter with two distal markers. Two types of coils, a 0.015-inch-diameter "regular" coil and a 0.014-inch-diameter "soft" coil, were used. RESULTS: A total of 569 coils were used, 541 of which were detached. The number of coils in ranged from four to 53 (average number of coils, 14). The coils passed easily through the microcatheter. The detachment maneuver occurred within 10 to 25 s with 20 turns of the introducing wire. No premature coil detachment occurred. Complete occlusion of the vessel lumen was achieved in 35 cases. In three cases, 80% to 90% occlusion was achieved. In two cases, 70% to 80% occlusion was achieved. There were no device-related complications. CONCLUSION: The detachment system was safe, reliable, consistent, and fast. This is a useful system for coil embolization in neurovascular applications.

Adult↗

PubMed2000

Spinal canal stenosis in L-2-hydroxyglutaric aciduria.

We describe 2 brothers with L-2-hydroxyglutaric aciduria who developed severe spastic tetraparesis in their 30s. They also had an underlying condition of high-grade cervical spinal canal stenosis diagnosed by magnetic resonance imaging. They were operated on to decompress the spine, and the preexisting gait disturbances slowly diminished after the decompression. Since most people with L-2-hydroxyglutaric aciduria show spastic signs in their legs and arms, we conclude that cervical spinal canal stenosis may be the underlying reason and may be linked to this rare metabolic disorder.

Adult↗

PubMed2000

Detectability and detection rate of acute cerebral hemisphere infarcts on CT and diffusion-weighted MRI.

Our purpose was to compare the detectability and detection rate of acute ischaemic cerebral hemisphere infarcts on CT and diffusion-weighted MRI (DWI). We investigated 32 consecutive patients with acute hemisphere stroke with unenhanced CT and DWI within 6 h of stroke onset. The interval between CT and DWI ranged from 15 to 180 min (mean 60 min). Infarct detectability on CT and DWI was determined by comparing the initial CT, DWI and later reference images in a consensus reading of five independent examiners. The "true" detection rate was assessed by analysing all single readings. Two patients had intracerebral haematomas on DWI and CT and were excluded. There were 27 patients with ischaemic infarcts; all were visible on DWI and proven by follow-up. DWI was negative in three patients without a final diagnosis of infarct (100% sensitivity, 100% specificity, chi2 = 30, P < 0.0001). Ischaemic infarcts were visible on 15 and not seen on 12 CT studies (55 % sensitivity, 100% specificity, chi2 = 1.48, P = 0.224). With regard to the single readings (30 examinations x 5 examiners = 150 readings), 63 CT readings were true positive and 72 false negative (sensitivity 47 %, specificity 86%, chi2 = 2.88, P = 0.089). Of the DWI readings 128 were true positive and 7 false negative (sensitivity 95%, specificity 87 %, chi2 = 70.67, P < 0.0001). Interobserver agreement was substantial for CT (chi = 0.72, 95 % confidence interval, 0.6-0.84) and DWI (chi = 0.82, 95 % confidence interval, 0.46-1). Taken together, detectability and detection rate of acute (< 6 h) hemisphere infarcts are significantly higher with DWI than with CT.

Brain↗

PubMed2000

Unusual pattern of leukoencephalopathy after morphine sulphate intoxication.

We report a 14-year-old girl with an unusual pattern of leukoencephalopathy after intentional intoxication with morphine sulphate tablets. Toxicological analysis showed exceedingly high levels of morphine and its metabolites. MRI disclosed a leukoencephalopathy with high signal from the centrum semiovale, corpus callosum and cerebellar white matter on T2-weighted images. These findings could be only partially explained by a hypoxic-ischaemic event; neurotoxic effects must be considered in this atypical leukoencephalopathy.

Adolescent↗

PubMed2000

Phase-contrast MR imaging of the cervical CSF and spinal cord: volumetric motion analysis in patients with Chiari I malformation.

BACKGROUND AND PURPOSE: Most previous MR studies of the dynamics of Chiari I malformation have been confined to sagittal images and operator-dependent measurement points in the midline. To obtain a deeper insight into the pathophysiology of the Chiari I malformation, we performed a prospective study using axial slices at the level of C2 to analyze volumetric motion data of the spinal cord and CSF over the whole cross-sectional area. METHODS: Eighteen patients with Chiari I malformation and 18 healthy control subjects underwent cardiac-gated phase-contrast imaging. Cross-sectional area measurements and volumetric flow/motion data calculations were made for the following compartments: the entire intradural space, the spinal cord, and the anterior and posterior subarachnoid space. RESULTS: The most striking feature was an increased early systolic caudal and diastolic cranial motion of the spinal cord in the patients. CSF pulsations in the anterior subarachnoid space were unchanged at systole but showed an impaired diastolic upward flow. In the posterior compartment, the CSF systole was slightly shortened, with an impairment of diastolic upward flow. Fourteen of the 18 patients had associated syringeal cavities. This subgroup showed an increased systolic downward displacement of the cord as compared with patients without a syrinx. CONCLUSION: Obstruction of the foramen magnum in patients with Chiari I malformation causes an abrupt systolic downward displacement of the spinal cord and impairs the recoil of CSF during diastole.

Adolescent↗

PubMed2000

Efficacy of trisacryl gelatin microspheres versus polyvinyl alcohol particles in the preoperative embolization of meningiomas.

BACKGROUND AND PURPOSE: Trisacryl gelatin microspheres are a new, commercially available nonabsorbable embolic agent. The purpose of this study was to evaluate their efficacy in the preoperative embolization of meningiomas as compared with polyvinyl alcohol (PVA) particles of various sizes. METHODS: In 30 consecutive patients, trisacryl gelatin microspheres (150-300 microm) were used for the preoperative superselective embolization of meningiomas (group 1). Thirty other consecutive patients had embolization with PVA particles of 45 to 150 microm (n = 15, group 2) and of 150 to 250 microm (n = 15, group 3). Extent of devascularization, intraoperative blood loss, blood transfusion, and hemostasis at the time of surgery were recorded for every patient. The inflammatory reaction, the extent of necrotic areas, and the most distal intravascular location of the embolic agent (arterial, arteriolar, precapillary, capillary) were recorded. RESULTS: There was no significant difference in the extent of angiographic devascularization among the groups. Intraoperative blood loss differed significantly between groups 1 and 2 and groups 1 and 3, but not between groups 2 and 3. The trisacryl gelatin microspheres were located more distally in tumor vessels than were the PVA particles of either size. The extent of intratumoral necrosis was not significantly different between the two embolic agents. In all groups there was a mild inflammatory tissue reaction in the vicinity of the embolic agent. CONCLUSION: Trisacryl gelatin microspheres may be effective in the preoperative embolization of meningiomas, producing significantly less blood loss at surgery than seen with PVA particles of either size, possibly because of the significantly more distal vascular penetration of the microspheres.

Acrylates↗

PubMed2000

MR spectroscopy in gliomatosis cerebri.

BACKGROUND AND PURPOSE: The diagnosis of gliomatosis cerebri with MR imaging is known to be difficult. We report on the value of MR spectroscopy in the diagnosis, grading, and biopsy planing in eight patients with histopathologically proved gliomatosis cerebri. METHODS: Patients underwent MR imaging and MR spectroscopy (single-voxel point-resolved spectroscopy [PRESS] at 1500/135, and chemical-shift imaging [CSI] PRESS at 1500/135) before open (n = 4) or stereotactic (n = 4) biopsy. In six patients who underwent CSI, biopsy samples were taken from regions of maximally elevated levels of choline/N-acetylaspartate (Cho/NAA). RESULTS: All patients showed elevated Cho/creatine (Cr) and Cho/NAA levels as well as varying degrees of decreased NAA/Cr ratios, which were most pronounced in the anaplastic lesions. In low-grade lesions, there was a maximum Cho/NAA ratio of 1.3, whereas in anaplastic tumors, the maximum Cho/NAA level was at least 2.5. Spectra in two patients with grade III lesions revealed a lactate peak; lactate and lipid signals were seen in two patients with grade IV lesions. Biopsy specimens from regions with maximally elevated levels of Cho/NAA showed dense infiltration of tumor cells. CONCLUSION: MR spectroscopy might be used to classify gliomatosis cerebri as a stable or a progressive disease indicating its potential therapeutic relevance.

Adolescent↗

PubMed2000

MR imaging- and MR spectroscopy-revealed changes in meningiomas for which embolization was performed without subsequent surgery.

We describe our experience with follow-up MR imaging and MR spectroscopy in two patients after embolization of meningiomas without subsequent surgery. In both patients there was a marked reduction in tumor size and a decrease in contrast enhancement associated with spectroscopic signs of fatty degeneration. We did not observe regrowth; however, in one patient with incomplete angiographic devascularization, residual vital tumor tissue was seen at follow-up examinations.

Aged↗

PubMed2000

Is there a benefit of preoperative meningioma embolization?

OBJECTIVE: To evaluate the effect of preoperative embolization of meningiomas on surgery and outcomes. METHODS: In a prospective study, 60 consecutive patients with intracranial meningiomas who were treated in two neurosurgical centers were included. In Center A, embolization was performed for none of the patients (n = 30). In Center B, 30 consecutive patients with embolized meningiomas were treated. Preoperatively, tumor size and location, neurological status, and Barthel scale score were recorded. In Center B, the extent of tumor devascularization was evaluated using angiography and postembolization magnetic resonance imaging. Intraoperatively, blood loss, the numbers of blood units transfused, and the observations of the neurosurgeon concerning hemostasis, tumor consistency, and intratumoral necrosis were recorded. Postoperatively, the neurological status and duration of hospitalization were recorded. Six months after surgery, the outcomes were assessed using the Barthel scale and neurological examinations. RESULTS: The mean tumor sizes were 22.9 cc in Center A and 29.6 cc in Center B (P > 0.1). The mean blood losses did not differ significantly (646 ml in Center A versus 636 ml in Center B; P > 0.5). However, for a subgroup of patients with subtotal devascularization (>90% of the tumor) on postembolization magnetic resonance imaging scans in Center B, blood loss was less, compared with the entire group in Center A (P < 0.05). The observations of the neurosurgeon regarding hemostasis, tumor consistency, and intratumoral necrosis did not differ significantly. There were no surgery-related deaths in either center. The rates of surgical morbidity, with permanent neurological worsening, were 20% (n = 6) in Center A and 16% (n = 5) in Center B. There was one permanent neurological deficit (3%) caused by embolization. CONCLUSION: In this preliminary study, only complete embolization had an effect on blood loss. The value of preoperative embolization for all meningiomas must be reconsidered, especially in view of the high costs and risks of embolization.

Adult↗

PubMed1999

Silent embolism in diagnostic cerebral angiography and neurointerventional procedures: a prospective study.

BACKGROUND: Cerebral angiography is associated with a small but definite risk of neurological complications with an unknown incidence of clinically silent embolism. We assessed the neurological complication rate compared with the frequency of silent embolism after angiography METHODS: We used diffusion-weighted magnetic resonance imaging (MRI) before and after angiography to assess embolic events. 100 consecutive angiographies (66 diagnostic and 34 interventional procedures) were done on 91 patients. Patients underwent neurological assessment before, immediately after, and 1 day after angiography. FINDINGS: Before angiography, no abnormalities were seen on diffusion-weighted MRI. Diffusion-weighted MRI showed 42 bright lesions in 23 patients after 23 procedures (17 diagnostic, six interventional) in a pattern consistent with embolic events. There was no new neurological deficit after any angiographic procedure. After diagnostic angiography in patients with a history of vasculopathy, the frequency of lesions was significantly higher than in patients without vascular risk factors (12 [44%] of 27 vs five [13%] of 39 patients, p=0.03). In diagnostic angiography, the appearance of lesions was significantly correlated with whether vessels were difficult to probe (p=0.01), amount of contrast medium needed (p<0.01), fluoroscopy time (p<0.01), and use of additional catheters (p=0.02). INTERPRETATION: After diagnostic and interventional cerebral angiography, embolic events are more frequent than the apparent neurological complication rate. In diagnostic procedures, the incidence of embolism is closely related to a vascular risk profile.

Adolescent↗

PubMed1999

[Cerebral aneurysms in the posterior circulation. Treatment results in 44 consecutive cases].

PURPOSE: Evaluation of clinical and morphological results in 44 consecutive patients with 45 aneurysms of the posterior circulation. METHODS: Retrospective analysis of patient charts and angiograms of all vertebrobasilar aneurysms diagnosed in our department between 10/95 and 08/99. All aneurysms were treated. RESULTS: 36/44 pts had a hemorrhage. Hunt/Hess (HH) gradings were as follows: HH1 in 10, HH2 in 6, HH3 in 9, HH4 in 10 cases, and HH5 in 1 case. 38 pts with 39 aneurysms were treated exclusively in the endovascular way, 3 pts with 3 aneurysms were operated on. 3 patients had to be operated upon following insufficient endovascular treatment. Endovascular treatment resulted in 63% total and 27% subtotal occlusions, results being stable in 85%. For our pts as a whole, the grading according to the Glasgow Outcome Scale (GOS) was GOS1 in 4, GOS3 in 8, GOS4 in 7, and GOS5 in 25 cases. CONCLUSION: Despite a less favourable clinical status of pts pre-treatment, the results of our interdisciplinary concept compare favourably with those of other surgical or interventional groups.

Adult↗