Biomedical subjects

G Pendl

Publications and source records attributed to G Pendl.

At least 73 records · Page 4Linked to original sources

PubMed1995

Evidence for segregated pain and temperature conduction within the spinothalamic tract.

The lateral spinothalamic tract, located in the anterolateral quadrant of the white matter of the spinal cord, is one of the most important structures in transmitting pain within the central nervous system. It has been known for almost a century that destruction of fibers in this tract results in analgesia contralateral to the lesion. The effectiveness and clinical importance of interruption of the lateral spinothalamic tract has been proven in many studies. Today cordotomies are still a useful neurosurgical treatment modality, especially when pain can no longer be sufficiently controlled by analgesic drugs. Although analgesia on the contralateral side is the desired effect, one must also expect to cause disturbance in temperature sensation when performing a cordotomy. The authors' observations showed that after a cordotomy the dermatome level of analgesia can be variable within certain limits, which is in accordance with the literature. Surprisingly, however, the loss of temperature sensation may differ significantly from the loss of pain sensation. It was also found to be possible to perform a successful cordotomy without altering the sensation of temperature at all. This indicates that pain and temperature sensations may be conducted via separate pathways. Possible mechanisms underlying this phenomenon are discussed.

Analgesia↗

PubMed1994

Boron neutron capture therapy: boron biodistribution and pharmacokinetics of Na2B12H11SH in patients with glioblastoma.

Data on biodistribution and pharmacokinetics of Na2B12H11SH are few and lack in standardization. This study comprises a uniform series of 10 patients with glioblastoma administered Na2B12H11SH i.v. 24 h before surgery at a dose level used in earlier therapeutical trials (75 mg/kg body weight). Boron concentrations in tumor, normal brain, peritumoral edematous brain, blood, and urine were determined by inductively coupled plasma-atomic emission spectroscopy 24 h after Na2B12H11SH administration; boron uptake in tumor (mean, 12.2 micrograms/g) was sufficiently selective compared to concentrations in normal and edematous brain (1.2 and 2.3 micrograms/g, respectively). Mean concentration ratio of tumor:blood was slightly above unity. Boron concentration in blood decreased according to an open two-compartment model, mean excretion in urine over 24 h was 81.9%. The only side effect was an inconstant facial flush. Among efforts aiming at an optimized treatment protocol a dose escalation study seems to be justified.

Borohydrides↗

PubMed1994

Radiosurgery with the first Austrian cobalt-60 Gamma-unit. A one year experience.

During the period of one year, from the 21. 4. 1992 to 21. 4. 1993, a total of 201 radiosurgical sessions on 181 patients were performed with the first Austrian Gamma-unit in Graz. 42% of radiosurgical sessions were undertaken for malignomas, 20% for meningiomas, 11.5% for vascular malformations, 9% for neurinomas, 8.5% for low grade astrocytomas and glomus jugulare tumours, 5% for sellar and suprasellar lesions, and 4% for functional disorders. Dose plan data for all the lesions treated are shown. Clinical and imaging data of the first year which are available for 120 patients (66%) are presented and discussed.

Adult↗

PubMed1994

Subcellular boron-10 localization in glioblastoma for boron neutron capture therapy with Na2B12H11SH.

Because of the short range of the highly energetic particles helium-4 and lithium-7 that results from neutron-induced disintegration of boron-10, the efficacy of Boron Neutron Capture Therapy (BNCT) is heavily dependent on 10B-microlocation. Despite the crucial importance of boron-10, there is little specific information with regard to the agent currently used for inducing BNCT, namely Na2B12H11SH. In the present study, a subcellular 10B-location was investigated in tumor tissue obtained from seven patients with glioblastoma World Health Organization Grade IV. These patients received Na2B12H11SH at doses used in therapeutic trials (75 mg/kg body weight in five patients, and 150 mg/kg body weight in two patients, respectively). In three cases, boron-10 was identified in glioblastoma cells by laser microprobe mass analysis. In these tumors, boron-10 was found only in the nuclei of neoplastic cells but not in other cell compartments. These preliminary results suggest a predominant association of Na2B12H11SH with the nuclei of malignant glioma cells and thus support the value of Na2B12H11SH as a suitable boron carrier for BNCT.

Borohydrides↗

PubMed1993

Primitive neuroectodermal tumor (PNET) extending into the cerebellopontine angle: case report.

The most common primary tumors of the cerebellopontine angle are growths of the 8th cranial nerve. The occurrence of other tumors in this area is very rare and may cause neuroradiological misinterpretation. We report the findings in a 37-year-old male patient suffering from a primitive neuroectodermal tumor (PNET) extending from the latero-basilar cerebellar hemisphere into the cerebellopontine angle (CPA) and causing cerebellar dysfunction as well as symptoms of typical cerebellopontine angle lesions. Differential diagnosis of tumors found in this area is given as well as a histological description of the tumor along with immunohistochemical findings and aspects of possible prognostic relevance.

Adult↗

PubMed1992

Surgery of tumours of the lateral ventricle.

Tumours of the lateral ventricle in most cases enlarge significantly before signs and symptoms are exhibited. In the years between 1980 and 1991 we encountered 55 patients of all age groups with tumours of the lateral ventricle. All were diagnosed either by CT or MRI, and in lesions with good enhancement on CT additional angiography was performed. All 55 tumours were operated upon using microsurgical techniques. The approach was chosen according to the location of the tumour, preferably transcortical. In selected cases large tumours were removed in a two-stage operation. Only in one frontal horn and Cella media tumour an interhemispheric transcallosal approach was used. Postoperative or surgically related mortality was experienced in 3 cases. Life expectancy and morbidity were dependent upon histology.

Adolescent↗

PubMed1991

Microsurgery of intrinsic midbrain lesions.

The advanced tools of neuro-imaging provide sufficient details for an appropriate open microsurgical approach to those lesions, which are well circumscribed even as intrinsic lesions of the midbrain. 30 reported cases with only 3 postoperative death related to surgery but otherwise no morbidity except in one case, demonstrate the safety of modern microsurgical techniques, provided the case has been well selected for surgery and the appropriate approach is chosen well. A clear histological diagnosis also is the foundation for the additional methods of postoperative treatment.

Adolescent↗

PubMed1991

Clinico-radiological spectrum of giant intracranial aneurysms.

A review of a series of 56 patients with a giant intracranial aneurysm showed that 28 presented with signs related to the mass effect and 19 with subarachnoid hemorrhage (SAH). Additional clinical signs observed were seizures, ischemia, and endocrinological disturbances. Fourty-five aneurysms involved the carotid artery territory and eleven the vertebrobasilar system. On computed tomography (CT) images partially thrombosed aneurysms (23 cases) showed 1) a marginal or central "target" appearance on contrast enhanced scans corresponding to the non-thrombosed lumen as demonstrated by angiography, 2) capsular enhancement in 16 cases and 3) calcifications in 9. SAH occurred in 13 and 6 cases of non-thrombosed and partially thrombosed aneurysms, respectively. Magnetic resonance imaging (MRI) in 6 cases showed several layers of thrombosis in 4 cases and a small signal void close to the parent artery. In one case of a non-thrombosed aneurysm, thrombosis was mimicked by flow artifacts of MRI.

Cerebral Angiography↗

PubMed1990

Surgical treatment of epilepsy.

Seventy patients with intractable epilepsy were surgically treated. Thirty-three patients underwent a stereotactic procedure and in all as a first-stage operation fornicotomy was performed. Because of inadequate results in 14 patients, an additional stereotactic intervention was necessary; the targets were amygdala, thalamus, and Forel's H-field, and the final outcome of these patients was 9 (27%) seizure-free, 19 (58%) improved, and 5 (15%) unchanged. In 3 patients a selective amygdalo-hippocampectomy was performed with 2 seizure-free patients and one with improvement. Topectomy in focal epilepsy in 5 patients resulted in freedom from seizures in all cases. In 23 patients a lobectomy was performed; 10 (43%) were seizures-free, 8 (35%) were improved, and 5 (22%) were unchanged. In 6 patients only a pathological lesion was resected. Our results speak in favour of ablative surgery. However, stereotactic operations are indicated in cases with secondary generalization and dissipated foci on the dominant hemisphere.

Adult↗

PubMed1990

Microsurgery of midbrain lesions.

Of 41 patients with midbrain lesions, 25 underwent definitive surgical exploration. In 16 patients surgical exploration was not warranted, since the patients had only slight neurological deficits and longstanding histories or consent was not given. The infratentorial supracerebellar approach proved to be the ideal method of exposure in 20 patients, in whom the lesion was located in the more dorsal aspect of the midbrain. In 6 of these patients the mass lesion extended from the cerebellum into the midbrain and, therefore, a transcerebellar route was also needed for exposure. In 5 patients the subtemporal approach was chosen. Three patients died as a result of the operation, but in the other 22 patients no increase in morbidity after surgery was apparent and the immediate postoperative course was normal. Five patients with malignant tumors died from recurrence despite radiotherapy. The remaining 17 patients have been doing well up to 14 years after surgery, but 3 had only limited follow-up. This experience with surgical exploration and total resection or evacuation of midbrain lesions in 25 patients should prove the safety of modern microsurgical techniques. Emphasis is placed on the benefit of microtopographic considerations in the choice of the most suitable approach to these deep-seated lesions.

Adolescent↗

PubMed1989

[Therapy refractory pain of malignant origin].

In 50 patients with intractable pain due to malignancy an intrathecal application of morphine was performed. The follow-up extended in 28 patients till their death. Overall 46% of the patients had a profit of the therapy for the whole remaining life, 25% at least half of it. The main indication to intrathecal infusion of morphine is in multiloculare and midline pain especially in advanced cancer stage.

Adult↗

PubMed1988

Microsurgery of midbrain lesions.

Between 1973 and 1987 a total of 38 patients with midbrain lesions were encountered. In 15 cases surgical exploration was not warranted, 23 patients underwent definitive surgical exploration. The infratentorial supracerebellar approach proved to be the ideal route for the exposure of the 21 lesions which were located in the more dorsal aspect of the midbrain; in 7 cases the extension of the mass lesion reached from the cerebellum into the midbrain and, therefore, the exposure demanded a transcerebellar route. In one case with a hamartoma in the interpeduncular cistern and another case of a metastasis of the right cerebral peduncle the subtemporal approach was chosen. Three patients died as a consequence of the operation, but in the other 20 there was no increase in morbidity after surgery and the immediate postoperative course was favourable. Four cases with malignant tumours died from recurrence despite radiotherapy. The remaining 16 cases have been doing well up to 14 years after surgery.

Adolescent↗

PubMed1988

Symposium on ethics and morals related to antenatal treatment of pediatric neurosurgical disorders. Treatment of fetuses in utero--an opinion from central Europe.

In Austria, there is no need for treatment of defective fetuses in utero. First of all, the possibilities known so far are limited their effectiveness is debatable. Second, knowledge about fetal therapy is limited to a few specialists but so far is not practiced. The problems to be encountered in this new field and are discussed with regard to the ethical impact on the physician, the parents, and society, as well as the costs involved. The answer to this controversial subject is proposed using clear, irrevocable diagnostic procedures. Indication for surgery should cover the benefits to the child and parents and the benefits for society as well; justification of antenatal surgery should lead to a better understanding of the whole problem; all identical cases should be treated under identical circumstances; finally, justification for antenatal surgery or preterm delivery should not contradict or subvert our notion of fundamental and equal human rights. Progress in this field should be observed very critically.

Attitude of Health Personnel↗

PubMed1988

[Results of electrocoagulation of Gasser's ganglion in 250 patients with idiopathic trigeminal neuralgia].

In 250 patients with tic doulourex an percutaneous radiofrequency coagulation of the gasserian ganglion has been performed. In 92.2% of the cases the patients were post-operatively painfree. The follow-up extended in 122 cases over 7 years. In these patients a pain recurrency was noted in 27%. On behalf of low invasivity of the procedure the radio-frequency coagulation of the gasserian ganglion is a recommendable operation with low risk and high efficiency especially in old patients.

Adult↗

PubMed1987

[Brain tumors: early symptoms, therapy and prognosis].

A survey of the variability of brain tumors, their early symptoms and possibilities of a rational surgical approach and the limits of radio- and chemotherapy. The prognosis is discussed by the biological properties and choice of possible treatment.

Brain↗

PubMed1987

Microsurgery of pineal region lesions in children.

Sixteen patients of the pediatric age group (mean age 6.9 years) harboring a tumorous, cystic or vascular mass lesion of the pineal region were evaluated for clinical, neuroradiological and microsurgical aspects. The heterogenous histological pattern of the lesions reflected various clinical signs and neuroradiological features. Computer assisted tomography and magnetic resonance imaging were the main neurodiagnostic tools, although angiography was an important complementary investigation in selected cases. Microsurgical approach and removal of the tumorous and cystic processes proved to be the rational treatment. Additional treatment such as chemotherapy or radiotherapy was performed in malignant processes upon a precise histological evaluation of the tumor specimen.

Adolescent↗

PubMed1987

Serum melatonin levels: a new neurodiagnostic tool in pineal region tumors?

The pineal hormone melatonin (MLT) is secreted in a circadian rhythm with high serum levels during nighttime and low serum levels during daytime. Several authors have reported an altered secretion pattern of MLT in patients with pineal tumors and have proposed that MLT may be used as a tumor marker. In nine patients, a pineal region tumor was diagnosed by computer-assisted tomography. Before and after surgical removal of the tumor, several day- and nighttime serum samples were collected and MLT concentrations were estimated by radioimmunoassay. Before operation, five patients presented a normal circadian pattern of MLT secretion. In the remaining four subjects, MLT levels were undetectable or at the limit of detection, with no signs of a circadian secretion pattern. Eight patients were reexamined after tumor resection, when all but one had undetectable or very low MLT levels. The remaining subject, with a pineomesencephalic pilocytic astrocytoma, dislocating but not involving the pineal gland, presented a normal circadian secretion pattern of MLT after operation; in this case, tumor resection was possible without damaging the pineal gland. Thus, before operation, MLT deficiency rather than exaggerated serum levels may be used as a marker for pineal tumors that destroy the pineal gland. After tumor resection, serum MLT may serve to demonstrate complete pinealectomy.

Adolescent↗

PubMed1987

[Computerized tomography in space-occupying lesions of the pineal region. Neurosurgical aspects].

61 patients harboring a space-occupying or vascular lesion of the pineal region were investigated by computed tomography (CT). Out of this series in 50 patients the process was approached by microsurgical techniques. In these cases CT was compared to the intraoperative topographic site and additionally an exact histological evaluation was achieved. Surgical experience and histological results show, that the CT and Nuclear Magnetic Resonance Imaging are the most important diagnostic tools in the neuroradiological investigation of pineal region lesions. In some cases a histological diagnosis can be expected from CT. Furthermore the CT enables the neurosurgeon to evaluate the relation of the process to the different anatomical structures and its growth pattern. Thus CT represents a keystone in the microsurgical treatment of lesions of the pineal region.

Brain Neoplasms↗