PubMed Health⌕ Search

Biomedical subjects

A Laun

Publications and source records attributed to A Laun.

At least 19 recordsLinked to original sources
PubMed1998

Prognostic implication of histopathological, immunohistochemical and clinical features of oligodendrogliomas: a study of 89 cases.

Histopathological, immunohistochemical and clinical parameters were correlated with survival in 89 cases of oligodendroglioma (65 patients with grade II and 24 patients with grade III of the WHO classification). Median survival time and 5-year survival rate were 3.5 years and 76% for patients with oligodendroglioma grade II and 0.875 years and 23% for patients with oligodendroglioma grade III. The tumor biopsy specimens were immunohistochemically analyzed for Ki 67 (MIB-1), vimentin, glial fibrillary acidic protein (GFAP), neuron-specific enolase (NSE) and synaptophysin. MIB-1 nuclear labeling index ranged from 0.0% to 33.4%; vimentin-immunoreactive tumor cells were found in 25 cases. MIB-1 nuclear labeling index and vimentin immunoreaction showed a significant statistical correlation to the 5-year survival rate of the patients. Tumors with vimentin expression (n=25) and/or high MIB-1 labeling index (n=26) had a poorer prognosis than tumors lacking vimentin expression (n=57) and/or displaying a low MIB-1 labeling index (n=56). The expression of immunoreactivity for GFAP (n=53), NSE (n=23) and synaptophysin (n=15) appeared to be of no prognostic relevance. Patients with gross total tumor resection (n=47) had a median survival time and 5-year survival rate of 3.3 years and 84% compared to 1.2 years and 42% for patients with subtotal resection (n=41). The comparison between patients who underwent surgery alone (n=53) and those who had surgery plus postoperative radiation therapy showed no significant survival benefit from postoperative radiation therapy. In conclusion, tumor grade, MIB-1 labeling index, expression of vimentin and the extent of surgery are shown to be of prognostic relevance for patients with oligodendroglioma.

Adolescent↗
PubMed1995

[Modified Kirschner wire insertion for direct ventral screw fixation of dens fractures].

Since 1985 25 patients with a fracture of the odontoid process (dens) were operated in the Neurosurgical Department of the Justus-Liebig-University in Giessen. An early stabilization through an anterior approach was favoured for type II fractures, and for displaced type III injuries, according to the classification of Anderson and d'Alonzo. Two double threaded screws were implanted to reach a compression between the fragments and a stabilization of rotation. With patients having a large thoracic volume and/or a short neck there are often problems, to insert the K-wires in the correct angle, before the screw fixation is performed. For these cases we have developed a new device for the K-wire insertion. After technical examinations in specimen the device was successfully applied in clinical use. This device with its inherent advantages is presented and discussed in this paper.

Bone Screws↗
PubMed1995

[Correlation between the gradient constant of the theoretical pressure volume diagram (PVD) and the pressure volume index (PVI) in relation to brain pulse amplitude-mean pressure function].

In 54 neurosurgical patients--suffering from intracranial tumors, hydrocephalus or different kinds of brain injury--a catheter was implanted in the lateral ventricle for continuously monitoring of the intracranial pressure (ICP). The intraventricular injection of defined amounts of sodium clearance (1-2 cm3) was followed by increased values of intracranial mean pressure--(pm) and pulse-amplitude- (PA). The recorded data showed a high significant correlation after regression analysis. After determination of the pressure-volume-index (PVI) and the theoretical pressure-volume-diagram it was examined whether there is a linear correlation between the parameters of the craniospinal space (id) reserves (constant of gradient, (PVI, K of PVD)) and the gradients (CA) of the linear PA-PM-function. A significant linear relationship, however of weak degree, could be found between these two parameters. The linear PA-PM-function, therefore, can only be understood in restricted circumstances as a direct parameter of the intracranial spacial reserves. The underlying facts of these problems are dealt within this paper.

Brain Injuries↗
PubMed1994

Space-occupying cerebellar infarction. Clinical course and prognosis.

BACKGROUND AND PURPOSE: Because the timing and strategy of surgical intervention in massive cerebellar infarction remains controversial, we report our experience with the management of 52 such patients. METHODS: Case records, computed tomographic scans, surgical reports, and angiograms of 52 patients with space-occupying cerebellar infarction defined by computed tomographic criteria were reevaluated with regard to clinical course, etiology, therapeutic management, mortality, and functional outcome. RESULTS: In most cases clinical deterioration started on the third day after stroke, and a comatose state was reached within 24 hours. Sixteen patients were treated medically, and 30 by suboccipital craniectomy (22 plus ventriculostomy, 12 plus tonsillectomy). Ten patients primarily had ventriculostomy, which in 4 patients was supplemented by craniotomy because of continuing deterioration. Twenty-nine patients made a good recovery, 15 remained disabled, and 8 died. Even comatose patients had a 38% chance of a good recovery with decompressive surgery. Age older than 60 years (P = .0043) and probably initial brain stem signs (P = .0816) and a late clinical stage (P = .0893) were linked with a fatal or disabling outcome. CONCLUSIONS: Decompressive surgery should be the treatment of choice for massive cerebellar infarction causing progressive brain stem signs or impairment of consciousness.

Adult↗
PubMed1994

Stereotactic cysto-ventricular shunting in diencephalic (arachnoid) cysts.

Stereotactic cysto-ventricular shunting in three patients with congenital (subependymal cyst of the 3rd ventricle, subependymal cyst of foramen of Monroi, cyst of cavum septi pellucidi) is dealt with in this paper. The first operation was performed in May 1992 and the latest, being considered in this paper, in January 1993. All patients were admitted to our hospital suffering from increased intracranial pressure. CT-scans revealed an obstructive hydrocephalus subjected to the cystic lesions. After stereotactic puncture of these cysts, aspiration of their contents as well as biopsy of the wall a silicone catheter was implanted, thus constructing a permanent communication between the cyst and the lateral or 3rd ventricle. The internal catheter was connected to a subcutaneous burr-hole reservoir. All patients recovered uneventfully without neurological deficits. There were no operative complications. Follow-up CT-scans showed no recurrences of the cysts and obstructive hydrocephalus. Resulting from our experiences, it is quite obvious that the stereotactic internal shunt implantation seems to be a safe, proper and reliable method in the treatment of such cystic lesions. Open craniotomy or intracorporal shunting procedures and their immanent complications can be avoided for most cases of congenital intracranial cysts. It should, therefore, be the aim of further clinical investigations to prove the value of this method in additional cases.

Arachnoid Cysts↗
PubMed1993

Function tests on the neuroendocrine hypothalamo-pituitary system following acute midbrain syndrome, with special reference to computertomographical and magnetic resonance imaging results.

Seventeen patients underwent a neuroendocrinological function test at a mean 6.3 years following a severe craniocerebral trauma (CCT) accompanied by midbrain syndrome. An insulin hypoglycaemia test (IHT) and the combined pituitary anterior lobe test (CPALT) were applied. Whereas the IHT as maximum stimulator of the hypothalamo-pituitary system (HPS) showed an adequate reserve capacity, the CPALT yielded a partial limitation of the secretion dynamic in the somatotropic, adrenocorticotropic axis as well as a dysfunction in the FSH secretion. Neuroradiological tests could not establish substantial injury in the regio hypothalamica in any patient.

Adolescent↗
PubMed1993

Outcome of patients with aneurysmal and presumed aneurysmal bleeding. A hospital study based on 100 consecutive cases in a neurological clinic.

One hundred patients with spontaneous subarachnoid hemorrhage due to aneurysm or presumed aneurysm consecutively admitted to a neurological clinic and subjected to CCT during the first 72 hours were examined retrospectively. The outcome after two months as defined by the Glasgow Outcome Scale (GOS) was relatively good: 23% of the patients suffered management mortality (GOS I) (postoperative lethality 8%), 3% showed GOS-Grade II, 14% grade III, 17% grade IV, and 43% grade V. The extent of intracranial hemorrhage correlated well with the initial Hunt-Hess Grade which, in turn, had a strong influence on case fatality and the degree of disability. Lethal factors were: 1. massive subarachnoid hemorrhage together with a massive ventricular hemorrhage (p < 0.001), 2. massive subarachnoid hemorrhage together with an intracerebral hematoma > 20 ml (p < 0.05). Case fatality was lower when angiography was negative. In our study rebleeding (12%) and delayed cerebral ischemia (DCI) (18%) were less frequent and the lethality due to acute hydrocephalus (5%) and delayed cerebral ischemia (5%) was less pronounced than in comparable studies. The degree of disability (GOS) was directly related to the amount of intracranial blood, to the development of acute or chronic hydrocephalus, delayed cerebral ischemia and rebleeding. DCI occurred in 60% of patients with marked hydrocephalus. Rebleeding was more frequent in patients with acute hydrocephalus. Hydrocephalus, DCI, and rebleeding were associated with a poorer initial grade on the Hunt and Hess Scale.

Adult↗
PubMed1993

[Tuberculum sellae meningioma and hypophyseal adenoma in a woman].

The case of a 61 years old female patient with coincidental tuberculum sellae meningeoma and pituitary adenoma is demonstrated. Because of deteriorating vision of the left eye and bitemporal hemianopia the patient was investigated. Primary arranged computertomographical investigation showed a tall intra- and suprasellar solid homogeneous tumor. The plain skull film revealed sellar enlargement; angiographically craniolateral displacement of Aa. cerebri anteriores was found. Only MRI cleared up two coexisting tumors, an intrasellar lower enhancing tumor close to another extra-/parasellar. Neuroendocrinological investigations including insulinhypoglycaemiatest and the combined pituitary anterior lobe test showed findings to be seen typically in tuberculum sellae meningeomas. Only very discrete signs for a disturbance of anterior lobe secretion could be found. Postoperatively only a discrete deterioration of clinical symptoms and neuroendocrinological findings were noticed. The diagnosis of two coincidental tumors was confirmed histologically. Two years after operation no tumor-recurrence was seen. This case is comparable with cases published until now.

Adenoma, Chromophobe↗
PubMed1990

Comparative study of lyophilized human dura mater and lyophilized bovine pericardium as dural substitutes in neurosurgery.

In a prospective, controlled randomized study either lyophilized bovine pericardium or lyophilized human dura mater have been used as a patch for the closure of the dura in 102 patients. The aim of this investigation was to compare both materials in terms of immunogenic response of the patients. The rate of post-operative complications was comparably low in both groups (wound infection in 1/51 patients each). In regard of workability, thickness of the material and flexibility the pericardium patches were judged to be by far superior. Neither signs of a cellular nor of an intesified humoral response could be detected in patients who received the pericardium implants. Thus, lyophilized bovine pericardium seems to be a superior alternative for the surgical repair of dural defects.

Animals↗
PubMed1989

Rhinorrhea following dopamine agonist therapy of invasive macroprolactinoma.

We report on the occurrence of CSF rhinorrhea in a group of 17 patients harbouring macroprolactinomas who were treated with a dopamine agonist (DA, bromocriptine) alone or the combination of DA and transcranial operation. In 2 out of 17 cases shrinkage of tumour remnants during therapy with the oral or injectable form of bromocriptine was responsible for delayed occurrence of rhinorrhea. Operative procedures for successful closure of the fistulae were mandatory in both cases.

Adult↗
PubMed1988

Cranial nerve lesions following subarachnoid hemorrhage and aneurysm of the circle of Willis.

Fifty-eight of 570 patients with an aneurysm and/or subarachnoid hemorrhage displayed palsy of one or several cranial nerves. In 48 patients, this lesion occurred in the context of SAH (total n = 534). The oculomotor nerve was most frequently affected (38 cases), followed by the abducens nerve with the second-highest incidence (18 cases). The highest rate of cranial nerve symptoms occurred in cases of ophthalmic carotid aneurysms (83.3%). Damage to the abducens nerve regressed most rapidly.

Adult↗
PubMed1987

[Brain infarct caused by trauma-induced intracranial pressure elevation. Clinical and computerized x-ray tomography findings].

Of 327 patients admitted to hospital with signs of trauma-induced raised intracranial pressure 41 had infarcts demonstrated by computed tomography (CT). The most common site was the area supplied by the posterior cerebral artery, usually ipsilaterally. Experience so far indicates that the infarcts are most commonly caused by transient, dynamically produced occlusion of the artery, more rarely by venous congestion, resulting from the raised intracranial pressure. Comparison of the morbidity and mortality rate of patients with and without infarction after trauma with signs of raised intracranial pressure indicates that an infarct clearly worsens prognosis. Infarcts can be easily distinguished from contusional foci by CT, although both have decreased density, because the former spread within the supply area of a vessel and, similarly to embolic or arteriosclerotic infarcts, produce contrast enhancement after administration of contrast media as an expression of a disturbed blood-brain barrier.

Adolescent↗
PubMed1987

Acute direct and indirect lesions of the brain stem--CT findings and their clinical evaluation.

Since the introduction of computer tomography (CT) (Ambrose 1973, Hounsfield 1973) it has become an essential instrument in the diagnosis of acute intracranial lesions. The precise analysis of the CT and in particular the evaluation of the basal cisterns, yields results which are already wellknown, basically, from post-mortem investigations and clinical findings. However, while these were retrospective analyses and results, serial CT examinations which are free of risk for the patient and can be used in correlation with the clinical neurological findings, allow important assertions intra vitam, as well as a definitely better assessment of the prognosis. In addition to acute supratentorial lesions, acute and subacute infratentorial lesions are analysed and their clinical significance described. In this way, for the first time, the dynamics of the mechanical factors in raised intracranial pressure can be analysed. Important conclusions are drawn for the clinical management of the patients, and even some new indications for operation. Analysis of the acute hyperdense brain stem lesions--pathognomonic for haemorrhages--allows for the first time the diagnosis and continuous observation of traumatic and secondary haemorrhages caused by raised pressure, as well as spontaneous ones. As regards the mortality and morbidity, the results in this large series of traumatic and secondary haemorrhages are in striking contrast to previous analyses based on post mortem findings. Acute hypodense brain stem lesions are not amenable to any definite pathogenetic classification--softening, inflammatory lesions, tumours and oedema must all be considered. With acute lesions we are only dealing with infarcts, which are only incompletely assessable in the computer tomogram, and their diagnosis must still depend on the clinical findings. Secondary ischaemic lesions in acute raised intracranial pressure are identifiable in over 18% as infarcts which involve the entire territory of an artery. These additional space-occupying lesions are only survived by 11% of the patients. Hence the correlation which has been established between the basal cisterns and intracranial pressure is of great clinical significance. From our own research group several reports on different aspects of raised intracranial pressure and lesions of the brain stem have appeared since 1979. Similar analyses of partial aspects of the basal cisterns, have been published only recently, and came essentially to the same conclusions.

Acute Disease↗
PubMed1984

Cerebellar infarcts in the area of the supply of the PICA and their surgical treatment.

The authors report seven cases of cerebellar infarcts in the distribution of the PICA, of whom six were treated surgically. Only one patient died and he was not operated on. Although of the remaining six patients four were comatose, and two presented obvious signs of midbrain decerebration, all of them subsequently showed a really good quality of survival. In addition to the clinical details of the cases which are set out in tabular form, a survey of the literature is given and the indications for surgical treatment discussed. The exact interpretation of the CT scan and, in this context, particularly of the brain stem and its surrounding cisterns, above all the cisterns of the quadrigeminal plate and of the vein of Galen, gives decisive help in assessing the indications for suboccipital decompressive craniotomy. In view of the small number of cases, expressing the mortality rate in percentages would seem to be pointless. However, it appears appropriate to describe our experiences of the last two years and to recommend surgical treatment.

Adult↗
PubMed1984

Decerebrate rigidity and vegetative signs in the acute midbrain syndrome with special regard to motor activity and intracranial pressure.

Decerebrate rigidity, intracranial pressure and vegetative signs were studied in 25 patients. Advanced statistical techniques were used to analyse the interrelationships between muscle activity (IEMG), blood pressure (ABP), intracranial pressure (ICP), pulse rate (HR), respiratory rate (RR), and central venous pressure (CVP) occurring during paroxysms of decerebration. The pattern of reaction is influenced by compression or stress imposed on the brain stem at the tentorial incisure and is related to the degree of cisternal obstruction. Significant differences in reaction were disclosed between provoked and spontaneous decerebration posturing.

Adolescent↗
PubMed1984

[Obstructive hydrocephalus in cerebellar infarcts].

Large cerebellar ischaemic infarction may act as a space-occupying lesion and cause acute ventricular dilatation secondary to brain stem compression. 8 cases are regarded and the clinical course and therapy are discussed. After acute onset with vestibular and cerebellar symptoms, signs of progressive clouding of consciousness, accompanied often by signs of brain stem compression develop leading finally to decerebration syndrome. CT reveals an extensive hypodense area, usually in the lower part of the cerebellar hemisphere, compression and shift of the IVth ventricle and dilatation of 3rd and lateral ventricles. Drainage of ventricular fluid alone is not sufficient and the therapy of choice is the resection of infarcted tissue. Even in patients, who were operated in the early phase of decerebration excellent recovery was noted.

Adult↗
PubMed1984

Enterogenous intraspinal cysts.

The authors have reviewed the literature and recorded the distinguishing features of intraspinal enterogenous cysts. There are no characteristic clinical findings or history associated with this disease. These congenital space-occupying lesions frequently go undiagnosed, and the patient may be treated for many years as a case of multiple sclerosis. The teratogenic "determination period" is decisive for the development of anomalies affecting one, two, or all three of the germinal layers. All of these cysts belong to the same group, and their structure is an expression of the differing determination periods. The various theories about their etiology are discussed. True intraspinal enterogenous cysts are usually found in the cervical region. After careful operative removal, the prognosis is favorable.

Adult↗