Biomedical subjects

W E Hassler

Publications and source records attributed to W E Hassler.

11 recordsLinked to original sources

PubMed2001

[Spontaneous herniation of the thoracic spinal cord as the etiology of progressive Brown-Sequard syndrome. A description of 3 cases].

Spontaneous herniation of the spinal cord through a ventral dural defect is a rare neurological entity. We report on 3 patients treated in our clinic within 6 months. In 2 cases, the lesions were located at the BWK6 level and, in one case, at BWK2. The clinical presentation of all patients was f progressive Brown-Séquard's Syndrome. Diagnosis was confirmed by magnetic resonance imaging. In all cases, operation was performed. The myelon was replaced in the dural sleeve and the defect covered with a patch of lyophilized dura. After 1 year, symptoms were stable in 2 patients. In one case there was a slight deterioration because of an inexplicable swelling of the spinal cord which could not be controlled with a second operation. Pathophysiological, clinical, and radiological aspects are presented and discussed.

Adult↗

PubMed2000

Bypass-surgery and coil-embolisation in the treatment of cerebral giant aneurysms.

OBJECTIVE: Operative clipping is the most effective method in the treatment of cerebral giant aneurysms. But about 50% of all giant aneurysms are treatable this way. We want to report about eight patients with giant cerebral aneurysms, which were in our opinion "unclippable" without causing ischaemia in depending brain areas. METHODS: We describe eight cases of giant aneurysms of the pericallosal artery (n = 1) the middle cerebral artery (n = 3), the basilar tip (n = 3) and of the upper part of the basilar artery (n = 1). One patient with an aneurysm of the pericallosal artery was treated with an extra-intracranial saphenous vein bypass saphenous bypass, in three cases of middle cerebral artery aneurysms an extra-intracranial bypass was also done combined with a resection of the aneurysm. The four patients suffering from an aneurysm of the basilar artery got an extra intracranial bypass too followed by an occlusion of the aneurysm with GD-Coils. RESULTS: There was no peri-operative mortality and no severe peri- or postoperative complication. The neurological symptoms of all patients were unchanged after the operation. An angiographic control showed a complete obliteration of the aneurysm and a free running bypass in all cases. CONCLUSION: Bypass surgery and combined bypass surgery and coil embolisation are effective methods in the treatment of giant cerebral aneurysms, which can not be treated by clipping alone.

Anastomosis, Surgical↗

PubMed2000

Progressive spontaneous herniation of the thoracic spinal cord: case report.

OBJECTIVE AND IMPORTANCE: We report one case of spontaneous thoracic spinal cord herniation. To our knowledge, this is the first case involving radiological documentation of the development of herniation. Clinical features and surgical techniques are also presented. CLINICAL PRESENTATION: We describe the case of a 51-year-old female patient who experienced progressive Brown-Sequard syndrome for 2 years. Three magnetic resonance imaging examinations were performed; they revealed the progressive development of anterolateral spinal cord herniation at the level of T6 during those 2 years. INTERVENTION: After laminectomy at T6, the herniated myelon was microsurgically removed and the neurological symptoms improved. CONCLUSION: We present the possible causes, the proposed pathophysiological mechanisms, and the clinical and radiological development of this rare entity, with a review of the literature published to date. We propose that a preexisting weakness of the ventral dural fibers, combined with abnormal adhesion of the spinal cord to the anterior dural sleeve, leads to progressive herniation throughout life. Microsurgical treatment may halt the exacerbation of the neurological symptoms.

Brown-Sequard Syndrome↗

PubMed1999

Prediction of the post-comatose motor function by motor evoked potentials obtained in the acute phase of traumatic and non-traumatic coma.

OBJECTIVE: To define the value of electrically elicited motor evoked potentials (MEP), obtained during the initial phase of the coma, for correct prediction of the post-coma motor status. METHODS: Fifty-two patients were investigated by MEP within 72 hours after onset of the coma. It was the aim to correlate the MEP findings to the motor function two months after coma onset. RESULTS: Three patients with normal MEP showed no post-coma motor deficit. In 21 patients, a bilateral, symmetric prolongation of the central motor conduction time (CMCT) was registered. Eighteen of these 21 patients (86%) showed a normal post-coma motor status. In 28 patients, unilaterally absent evoked potential, or unilaterally prolonged CMCT, or bilaterally prolonged CMCT with significant difference in each hemisphere were observed. A post-coma contralateral paresis was found in 25 of these 28 patients (89%). That paresis was functionally important in 15 patients (54%) and functionally unimportant in 13 patients (46%). CONCLUSION: We identified certain MEP patterns (unilateral extinction of the evoked potential, unilateral, bilateral prolongation of the CMCT with significant "side" difference), which indicated a pyramidal tract lesion and a post-coma motor deficit with an accuracy of 89%. This refers to the motor results, which may not be the final post-coma motor results which are usually assessed six months after the coma onset. The MEP changes did not allow one to predict the severity of the paresis. The accuracy of prediction of a motor deficit increased from the MEP finding of unilaterally prolonged CMCT to the MEP finding of unilateral extinction of the potential. The most common finding, bilateral central motor slowing without significant "side" difference, did not indicate a post-coma paresis in 86%, leading to the assumption, that bilateral, symmetrical prolongation of the CMCT was not caused by lesions of the descending motor pathways, but by the drugs administered for treating the comatose patient. In conclusion, MEP allows one to predict the presence of a post-coma motor deficit with a high degree of accuracy already in the initial phase of coma, but MEP fails to predict the severity of that deficit.

Acute Disease↗

PubMed1999

Brain tumor surgery in geriatric patients: a critical analysis in 44 patients over 80 years.

BACKGROUND: The decision of whether to operate on brain tumors in elderly patients has not been made easier despite diagnostic and therapeutic advances facilitating their diagnosis. Little is known about the outcome of brain tumor surgery in patients 80 years or older probably because the number of these patients, although increasing, is still small. METHODS: The results of brain tumor surgery in 44 patients aged 80-86 years (mean age 83 years) were analyzed to determine which factors are relevant in the evaluation of the operative risk. The following parameters were analyzed with regard to the outcome: tumor volume, location, histopathology, preoperative condition, and concomitant diseases. RESULTS: At discharge 19 patients (43%) had improved while 14 (32%) remained unchanged. Nevertheless, the overall results were unsatisfactory in 10 patients (23%), of whom 5 died in hospital. Tumor location, volume, and histopathology did not correlate with the outcome. The preoperative cerebrovascular condition and the existence of multiple concomitant diseases were clearly the determining factors for the outcome. CONCLUSIONS: These results indicate that patients with life-threatening tumors or those causing persistent and intolerable brain dysfunction suffering from symptomatic cerebrovascular atherosclerosis as well as from multiple treatment requiring concomitant diseases did definitely not benefit from surgery.

Aged↗

PubMed1999

New device to treat chronic subdural hematoma--hollow screw.

Different surgical approaches exist for the treatment of chronic subdural hematoma. None of these approaches is superior to the other, so a minimal-invasive device (a hollow screw) was developed. The system consists of a stable hollow screw of surgical steel with a perforated tip, a hand-drill, screwdriver with guide, and collection bag. To place the screw in the skull local anesthesia is necessary followed by stab incision and percutaneous trephination. The screw is then placed in the bone and the guide removed. After spontaneous drainage and irrigation, a closed drainage system with a collection bag is connected with the screw. First results with the new technology are promising, with a high rate of completely treated patients and a low rate of complications. Two of 86 patients had a local skin infection after implantation of the screw, and in 22 patients the procedure was repeated due to one or more cases of recurrent or residual hematoma. No neurological deterioration was caused by the screw or the surgical approach. The advantages of this new system are: quick and simple procedure, minimal invasive, excellent function, inexpensive and reusable.

Adolescent↗

PubMed1998

Spondylodiscitis after lumbar discectomy. Incidence and a proposal for prophylaxis.

STUDY DESIGN: An analysis of the incidence of spondylodiscitis after lumbar disc surgery in 1642 patients. In 508 patients no prophylactic antibiotics were given. In 1134 patients a collagenous sponge containing gentamicin was placed in the cleared disc space. OBJECTIVES: To report the incidence of postoperative spondylodiscitis in cases in which no antibiotic prophylaxis was used, and to define the value of a collagenous sponge containing gentamicin in preventing disc space infections. SUMMARY OF BACKGROUND DATA: Spondylodiscitis is considered to be a rare complication of lumbar disc surgery. The retrospective design of most studies and the rare use of magnetic resonance imaging for early radiologic diagnosis suggest that the reported incidence rates may be underestimates. Postoperative spondylodiscitis is the result of intraoperative contamination and, theoretically, could be prevented by treating these patients with prophylactic antibiotics. METHODS: In 1642 patients, 1712 discectomies were performed. In 508 of these patients no prophylactic antibiotics were given; in 1134 of these patients a collagenous sponge containing gentamicin was placed in the cleared disc space. Clinical reexamination and, in cases of unsatisfactory results, laboratory and radiologic investigations were performed 4-8 weeks after surgery. RESULTS: In nineteen of the 508 patients who were not treated with antibiotic prophylaxis (3.7%) a postoperative spondylodiscitis developed, whereas none of the 1134 patients who received antibiotic prophylaxis became symptomatic (P < 0.00001). CONCLUSION: In the current study, a 3.7% incidence of postoperative spondylodiscitis was found in the absence of prophylactic antibiotics. Gentamicin-containing collagenous sponges placed in the cleared disc space were effective in preventing postoperative spondylodiscitis.

Administration, Topical↗

PubMed1995

Intraventricular recombinant tissue plasminogen activator for lysis of intraventricular haemorrhage.

A prospective series of 20 patients with moderate to severe intraventricular haemorrhage (IVH) was studied for the effect of intraventricular administration of recombinant tissue plasminogen activator (rt-PA) on reduction of haematoma volume and prognosis. On the day of haemorrhage ventriculostomy was performed and 2 to 5 mg of rt-PA were injected via the external ventricular drainage, followed by drainage closure for two hours. In 14 patients rt-PA treatment was repeated. Computed tomography showed complete clot lysis or substantial reduction of intraventricular haematoma volume in 19 patients within 96 hours; the clearance of the third and fourth ventricle preceded the clearance of the lateral ventricles. Decrease of ventricular enlargement was seen in all but one patient with initial ventricular dilatation. Increase of haematoma volume and ventricular size was found in one patient. Outcome was minor or no neurological deficit in nine patients, disabling neurological deficit in six patients, and vegetative status in four patients. One patient did not survive the IVH. Intraventricular treatment with rt-PA seems effective in rapid lysis of intraventricular haematoma and normalisation of impaired CSF circulation. This treatment may contribute to an improvement in prognosis of moderate to severe IVH.

Adult↗

PubMed1994

Pterional approach to the contralateral orbit.

Of a total of 80 operated intraorbital lesions, 2 were located in the posterior intraconal space, medial and inferior to the optic nerve. Because they were unfavorably located for standard surgical approaches, we operated via a contralateral pterional transsphenoidal-transethmoidal route. This technique provided excellent exposure and results in these two cases of intraorbital cavernous malformations. A brief description of the approach is presented.

Adult↗

PubMed1989

[Aneurysm of the vein of Galen as a possible cause of congestive heart failure: a report of 5 new cases].

We report on five newborns with an arterio-venous malformation of the vein of Galen. All newborns were cyanotic and in congestive heart failure without any evidence of congenital heart disease. Congestive heart failure in these cases was mainly due to an almost two-fold increase in cardiac output of approximately 8 l/min/m2 (normal: 4.5 l/min/m2). According to previous reports, mortality is very high in patients with this malformation when becoming symptomatic during infancy, and therapy by surgery or embolization is only successful in 10-30%. While three of our patients died shortly after diagnosis because of untreatable heart failure, the other two were operated on either by subtotal ligation of the draining vein or by ligation of 4 arterial feeders. In the first case secondary thrombosis of the aneurysm occurred and cardiac failure subsided. In the second case a large shunt remained and a balloon-embolization was performed successfully. However, in both patients severe neurologic defects occurred, the severity of which remains to be assessed later since the post-operative observation period is only 2 and 5 months, respectively.

Cerebral Angiography↗

PubMed1984

Intraoperative Doppler and real time sonography in neurosurgery.

Ultrasound Doppler sonography with miniaturized probes and high resolution offers new possibilities of intraoperative control of neurovascular procedures. Patency, flow direction stenoses and changes in resistance can be investigated atraumatically, repeatedly and without additional preparation. In bypass and aneurysm surgery, about 10% of the cases were shown by Doppler examinations to be unsatisfactory, with stenoses and occlusions. These could be immediately corrected without loss of time. In normal cases, the information on the local haemodynamics enlarges the knowledge as to the effects of the operation and make it safer. Real time ultrasonography, which can be easily adapted to neurosurgery, is a new atraumatic tool for localizing, in two dimensions, subcortical intrinsic processes, haematomas, ventricles ect. It is useful for guided biopsies and punctures and for the centering of the dura and brain incision over the middle of the lesion, especially in microsurgical procedures.

Carotid Arteries↗