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Biomedical subjects

A Pallua

Publications and source records attributed to A Pallua.

At least 19 recordsLinked to original sources
PubMed1999

Changes in the volume of residual pituitary adenomas in patients with adult-onset growth hormone deficiency during replacement therapy with the recombinant human growth hormone.

In the course of a prospective study concerning recombinant human growth hormone replacement therapy in adult-onset growth hormone deficiency, we determined the volumes of residual tumors in six patients with pituitary macroadenomas who had formerly been treated with surgery alone or surgery and external radiotherapy. Pituitary CT scans in direct coronal views were obtained at baseline, and at 6, 12 and 18 months. The volumes of the residual tumors were calculated from the tumor diameters assuming that the tumors had an ellipsoid shape. Tumor volumes did not change in one patient and were reduced in two patients. In three patients, clinically non-significant tumor expansion by a median of 23.6 +/- 13.2% (range, 21.1-62.0%) was noted after 12 to 18 months. This tumor expansion did not cause signs or symptoms of a mass effect and did not influence further treatment. One of the six patients discontinued treatment and no further change in tumor size, as determined by MRT, was noted over a mean follow up of 34 months. Treatment was continued for up to 38 months in five patients. In four of these five patients no further change in tumor size was detected. However, treatment with the growth hormone was stopped in one patient since a 30% expansion in tumor volume, elevating the optic chiasm, was noted on MRT. None of the patients developed deterioration of visual fields. Interestingly, tumor invasion of the cavernous sinus had been present initially in all three who displayed tumor expansion while on rhGH. This first study in which diameters of residual pituitary adenomas in patients on growth hormone replacement therapy were prospectively and carefully measured, permits no conclusion regarding a causal relationship between growth hormone and tumor expansion, owing to the small number of patients. However, the observed incidence is not much different from that in former studies without growth hormone replacement therapy. Nevertheless, a close observation of the pituitary by imaging studies at regular intervals appears to be mandatory, particularly in patients with invasive residual adenomas.

Adenoma↗
PubMed1999

Attenuated corticomedullary contrast: An early cerebral computed tomography sign indicating malignant middle cerebral artery infarction. A case-control study.

BACKGROUND AND PURPOSE: No neuroradiological markers have been characterized that support a timely decision for decompressive surgery in malignant middle cerebral artery (MCA) infarction (mMCAI). This case-control study was designed to analyze whether early cerebral CT (CCT) scanning provides reliable information for the prospective selection of stroke patients at risk of developing mMCAI. METHODS: Thirty-one pairs (n=62) were formed with cases (mMCAI) and controls (acute but not malignant MCA infarction) closely matched in terms of age, sex, and stroke etiology. CCT was performed within 18 hours of stroke onset and analyzed by a blinded neuroradiologist according to a defined panel of 12 CCT criteria. RESULTS: In terms of predicting mMCAI, the criteria of extended MCA territory hypodensities >67% and >50%, hemispheric brain swelling, midline shift, and hyperdense MCA sign exhibited high specificity (100%, 93. 5%, 100%, 96.7%, and 83.9%, respectively) but low sensitivity (45.2%, 58.1%, 12.9%, 19.4%, and 70.9%, respectively). Two criteria yielded high sensitivity (subarachnoid space compressed, 100%; cella media compressed, 80.6%) but low specificity (29% and 74.2%, respectively). The criterion of attenuated corticomedullary contrast yielded both high specificity (96.8%) and sensitivity (87.1%). The latter remained as the crucial criterion [Exp(B)=90.8; 95% CI, 5.8 to 1427. 5] in a 2-tailed logistic regression analysis with the strongest correlating parameters (Spearman correlation factor >/=0.6 or </=-0.6). CONCLUSIONS: The analysis of CCT scans within 18 hours of stroke onset revealed an attenuated corticomedullary contrast as the crucial CCT criterion, which, with both sufficient sensitivity and specificity, predicted mMCAI with 95% certainty.

Adult↗
PubMed1997

Image registration of MR and CT images using a frameless fiducial marker system.

A new system of fiducial stereotactic markers that can easily be adapted to various imaging modalities without losing image registration was developed and tested. Utilizing MR and CT imaging the accuracy of the new system was evaluated with phantom studies and preliminary patient studies. The markers are clearly visible without artifacts on both imaging modalities. The clear delineation of the marker dots on the images enables an accurate automated marker detection. Using the marker system, image registration was found to yield an accuracy of up to 1 mm, depending on the imaging modality and the employed marker arrangement. The presented marker system shall improve patient comfort in comparison to conventional fixed stereotactic frames if repeated, highly accurate registrations are necessary over longer periods.

Data Collection↗
PubMed1993

[The value of closed reduction of fractures of the lower thoracic and lumbar spine and computerized tomography follow-up].

The objectives of this prospective study were to investigate the value of the immediate closed reduction following fractures of the thoracolumbar and lumbar region. To reach that goal we performed a two stage CAT scan procedure before and after the reduction maneuver in a distinct patient population. The aim was not only to investigate the biomechanical process but also to evaluate and describe certain fracture types which have a good prognosis due to closed reduction according to posttraumatic spinal stenosis because of protruding posterior wall fragments and those who fail, respectively.

Follow-Up Studies↗
PubMed1993

[Meningiomas of the cerebellopontile angle].

Meningiomas of the cerebellopontine angle are the second most frequent type of tumours in that region and constitute more than one-third to one-half of all meningiomas of the posterior cranial fossa. On account of their vulnerable position in relation to the cranial nerves and due to the lack of available space, good postoperative results and a minimum of cranial neurological deficits can be achieved only if they are identified well in time and surgically removed. Basing on case histories and follow-ups of 15 selected patients, preoperative and postoperative symptoms of meningiomas of the cerebellopontine angle are discussed, possible misinterpretations pointed out and recommendations worked out to achieve an early clarification or surgical treatment.

Adult↗
PubMed1992

[The CT-controlled treatment possibilities in intervertebral disk prolapses].

A CT-controlled method for the treatment of lumbar and cervical disc prolapse is described. Compared with fluoroscopically controlled percutaneous lumbar discectomy, percutaneous treatment of the L5/S1 disc by a dorsal approach is possible even in the presence of high iliac crests, as is described in this paper. In the cervical region the risk of iatrogenic damage is reduced. In a small group of 42 patients, an attempt has been made to remove disc material which is intraforaminal, intraspinal, subligamentous or sequestered. Amongst 79 patients with lumbar and 15 patients with cervical disc prolapse treatment was successful in 85% (after 17 months of observation) and 93% (after 12 months of observation). These figures refer to the early results from a new method. The success of the method will have to be assessed after a larger number of patients has been treated and there has been a longer period of observation.

Adult↗
PubMed1992

[Neuroradiologic treatment possibilities of intervertebral disk displacement].

A CT assisted method for automated percutaneous lumbar discectomy (APLD) is described. With this technique and introduction of a "pull and push" method as well extruded and sequestrated herniated lumbar discs as cervical herniated discs can be treated. The CT assisted discectomy was performed in 70 patients. The success rate was 86% in the lumbar region and 93% for cervical herniated discs. We believe that this percutaneous technique will increase the importance of interventional neuroradiology for this common disease.

Adult↗
PubMed1989

Doppler and duplex sonography of the cervical arteries and correlations with other examinations. A field study in a population over forty years.

Of the population of a small Tyrolean village, 185 (56%) of the 329 inhabitants over 40 years were investigated by means of Doppler and duplex sonography, electroencephalography (EEG), electrocardiography (ECG), and neurological examination. Four subjects (2%) previously had a transitory ischemic attack (TIA) or stroke in the carotid territory. Sonographically detectable abnormalities in one or more extracranial arteries were present in 42 (23%) persons. Of the 14 subjects with more than slight abnormalities in the common or internal carotid artery two were symptomatic. Two additional cases with TIA or stroke did not show relevant lesions on sonographic examination. The presence of narrowing in the extracranial artery was not related to risk factors (hypertension, smoking, obesity) or abnormalities on ECG and EEG. This study shows 1) that the clinical relevance of ultrasound screening of the carotid arteries in an average population is 15%; 2) that significantly more patients with TIAs or strokes are found in the group with more severe sonographic findings (p = 0.001) than in the group with normal ultrasound results.

Carotid Arteries↗
PubMed1987

[Hydrocephalus following spontaneous subarachnoid hemorrhage].

In the period 1980-1985 221 patients presenting with subarachnoid haemorrhage were operated on at the Department of Neurosurgery of the University of Innsbruck. 26 patients (11.7%) of them required a ventriculoatrial or ventriculoperitoneal shunt. The relationship between the incidence of this complication and the various clinical features of subarachnoid haemorrhage is discussed. Computed tomography is the most important investigative tool for diagnosis and follow-up of hydrocephalus. The results after shunt operation are correlated with the site of the aneurysm and the pre-operative grade of the patient.

Adult↗
PubMed1985

Cerebrovascular lesions and livedo reticularis (Sneddon's syndrome)--a progressive cerebrovascular disorder?

Four cases are described in which livedo reticularis was associated with repeated cerebrovascular accidents, which eventually resulted in severe disability in two cases. Patients with severe disability had a history of many years, whereas two patients with little or moderate residual disability had a follow-up of 3 years each. CT scan revealed multifocal cerebral infarctions and cortical atrophy in all cases. Repeated cerebral angiograms, done in three cases, showed no signs of a vascular disease. There were no parameters that pointed to active immunological or inflammatory disorder. Neither clinical evidence of heart or large vessel disease was found. Observations suggest that a so-far unknown progressive cerebral vessel disease associated with livedo is the cause of a steady increase in multiple small cerebral infarctions. Because of the progressive character of the disease the search for effective therapy is needed.

Adult↗
PubMed1984

[Possibilities and limits of cranial computerized tomography for clinical psychiatry].

The interpretation of the computer-tomogramm is of practical value for diagnostic, therapeutic and prognostic aspects (Seitz [21]). Brain-atrophy is a pathomorphological change caused by a number of facts. Only the consideration of the patient's age, the degree of hydratation, serious internal or neurological diseases, endo- or extotoxic variables respectively, postnarcotic incidents or minimal brain damage allows an interpretation in accordance with the psychopathological symptoms.

Adult↗
PubMed1983

[Jopamidol, a non-ionic x-ray contrast medium--tolerance from a neurological viewpoint].

A double-blind trial was carried out in 80 patients, whereby jopamidol, the first stabilized non-ionic contrast medium, and meglumine iodamine were compared in 40 patients undergoing cranial computed tomography and 40 patients subjected to cerebral angiography. There was no difference in the quality of the radiographs. Jopamidol was better tolerated and caused significantly fewer side effects or complications than meglumine iodamine. Our evidence suggests that jopamidol has significant advantages over currently employed contrast media for cranial computed tomography and cerebral angiography.

Adolescent↗
PubMed1983

Central somatosensory conduction time and short latency somatosensory evoked potentials in post-traumatic coma.

Short latency evoked potentials (SEPs) were elicited by stimulation of the median nerve at the wrist and recorded simultaneously from the neck and the contralateral scalp in 44 comatose patients with signs of brain stem impairment due to head injury. Thirty-four patients were studied in acute coma on day 1 or 2 after brain injury. Twenty-three patients were studied in prolonged coma during days 3-12 after trauma. Six patients were examined in brain death. Brain stem involvement was divided clinically and by CT scan into secondary lesions due to supratentorial mass displacement and primary lesions due to direct violence to the brain stem. The central somatosensory conduction time (CCT) was measured by subtracting the peak latency of the major response from the neck (N14) from that of the primary scalp response (N20). The amplitude ratios (ARs) N20/N14 were calculated for each trace. Further asymmetries and absence of SEP over one or both hemispheres were noted. In cases in coma due to supratentorial lesions CCT and AR were close to normal in patients with good outcome. CCT increased and AR decreased with the worsening of outcome both in acute and prolonged coma. Asymmetries of SEPs indicated moderate or severe final disability. Patients with absent SEPs over one or both hemispheres due to supratentorial lesions died or survived severely disabled (1 case). In patients suffering from primary brain stem dysfunction, confirmed by a normal or slightly abnormal CT scan, prolonged CCT, asymmetric but also absent SEPs were also found in patients with good outcome both in acute and prolonged coma. AR was generally low in these cases. Early appearance of SEPs or early recovery of initially distorted SEPs and decrease of CCT in prolonged coma or during recovery was a favourable prognostic sign. Therefore even absent or severely distorted SEPs should be interpreted cautiously in patients who may suffer from primary brain stem involvement. Scalp SEPs were totally absent in patients with brain death.

Adolescent↗
PubMed1983

Incidence and prognostic value of spindles in post-traumatic coma.

One hundred and thirty-three EEGs were analysed from 80 comatose patients with signs of brain stem impairment due to head/brain injury. Seventy EEGs were taken in acute coma on day 1 or 2 after brain injury. Sixty-three EEGs were recorded in prolonged coma 3-12 days after brain injury. Brain stem involvement was divided by neurological signs and by CT scan into secondary lesions due to supratentorial mass displacement and primary lesions due do direct violence to the brain stem. Different EEG patterns were observed, but spindle activity was of special interest. Spindles were classified as typical (easily recognizable, well organized, 12-14 c/sec activity) or atypical (hardly recognizable, distorted form, 6-11 c/sec activity). Furthermore, asymmetries of spindles were noted. The spindles and their alterations were related to different stages of outcome. Spindles were seen in 91% of the EEGs in acute coma and in 30% in prolonged coma. In acute coma due to secondary brain stem involvement a good outcome was heralded by the occurrence of typical symmetrical spindles combined with early stages of secondary brain stem impairment at neurological examination. In cases of primary brain stem involvement typical spindles also suggested a good prognosis despite the observation of serious clinical signs (decerebrate posturing). The percentage of spindle activity decreased, and distortion and asymmetry of spindles increased with the worsening of outcome. Severe intracerebral lesions (confirmed by clinical and CT scan examinations) led to distortion, asymmetry and finally disappearance of spindles. In prolonged coma spindle activity was markedly reduced regardless of the final outcome. When spindles were present atypical and asymmetric forms significantly increased in patients with bad outcome. There were no significant differences in spindle activity in the different outcome categories, if primary and secondary brain stem lesions were compared.

Adolescent↗