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C B Ostertag

Publications and source records attributed to C B Ostertag.

At least 91 records · Page 5Linked to original sources
PubMed1986

Colloid cysts of the third ventricle. Open operative approach or stereotactic aspiration?

Colloid cysts of the third ventricle can cause hydrocephalus if they grow to the point where they occlude the foramina interventricularia. The operative approach via a craniotomy used to be the common method of treating these lesions. Now, in the era of CT- and MR-scanning, stereotactic aspiration should be preferred as an ideal method of simultaneously diagnosing and treating colloid cysts. Unlike open surgery, aspiration of colloid masses poses hardly any risk for the patient. Ten cases successfully treated by this technique are presented.

Adolescent↗
PubMed1984

Iodine-125 interstitial irradiation of virally induced dog brain tumours.

Brain tumours were induced by intracerebral inoculation of beagle puppies with Avian sarcoma virus (ASV) suspension. The inoculation produced solitary or multiple sarcomas in three dogs and intraventricular anaplastic gliomas in four dogs. At the time of the first tumour positive CT-control Iodine-125 seeds (activity 8.5-10.5 mCi) were placed into the lesion. The radioactive Iodine-125 implants produced sharply delineated calcifying necroses with vital unaffected tumour outside the necrosis. The necrotizing and calcifying effect was apparent after 18 days and complete after 97 days when a transitional zone was no longer detectable. The response of neoplastic tissue to low dose rate interstitial irradiation was distinctly different in terms of the volume of necrosis when compared with Iodine-125 radionecroses in healthy brain tissue.

Animals↗
PubMed1983

Sequential morphological changes in the dog brain after interstitial iodine- 125 irradiation.

Iodine- 125 seeds (3.55 mCi) were stereotactically implanted into the subcortical white matter of the left coronal gyrus in six beagle dogs. Morphological changes were studied at intervals ranging from 25 to 368 days after implantation. In all of the animals, there was a calcifying necrosis 3 to 6 mm in diameter with an adjacent small zone of demyelination. There were no signs of delayed radiation damage outside the demyelinated perifocal zone. The central tissue necrosis was sharply delineated and did not increase in size after 70 days, i.e., an accumulated dose of 18,000 cGy. In addition, widespread vasogenic edema was present in the homolateral hemisphere. The morphological changes observed differed in many aspects from those found with other radioactive sources, such as gold-198, yttrium-90, or iridium-192. The low energy gamma radiation, the absence of beta radiation, and the half-life of 60.2 days makes iodine-125 a favorable radioactive source to produce a well-defined necrosis without delayed radiation damage in the surrounding brain.

Animals↗
PubMed1982

Radiation effects of iridium-192 implants in the cat brain.

The radiation effects of 192Ir permanent implants into the cat brain were studied with respect to morphological changes, blood flow, brain water and electrolytes. 192Ir wires (10 animals) and non-radioactive silver wires (5 control animals) were placed stereotactically into the left internal capsule. Activity of 192Ir was 0.31 mCi, and accumulated dose at 5 mm distance was 3060 rad after 21 days and 4680 rad after 35 days, respectively. None of the animals presented a neurological deficit, and the EEG recording was without significant changes. Histological damage which could be attributed to the radiation was not observed. Serum proteins, however, were detected immunohistochemically in reactive astrocytes (3x), in macrophages (2x) and as diffuse perivascular accumulation. Brain water in the white matter near the implantation site increased from 68.6 to 73.2%, corresponding to a volume increase of about 17%. There was no change in the grey matter or the opposite hemisphere. Cerebral blood flow decreased slightly but there was no relationship with the development of edema. The findings suggest that low dose rate topical irradiation of the brain produces primarily membrane dependent changes, resulting in local brain edema.

Animals↗
PubMed1981

[Correlation of infarctions of the visual cortex with homonymous visual field defects. A computer tomographic study (author's transl)].

Computed tomography (CT) is a simple and non-invasive method of demonstrating infarctions of the visual cortex. Seventy-eight CT-proven infarctions were correlated with the visual field defects. This correlation between cortical infarctions and visual field defects is difficult to achieve by angiography because of the variations in the vascular supply. CT, on the other hand, provides a far better correlation, showing the functional-anatomical structure of the visual cortex by projection in three planes (transverse, sagittal, coronar). CT, however, can not replace angiography in cases where arteriovenous malformations are suspected.

Acute Disease↗
PubMed1980

[Comparative emission tomographic and transmission tomographic studies of cranial and intracranial diseases (author's transl)].

A comparative study was performed in 58 patients with brain lesions using emission computed tomography (ECAT -- single photon, Cleon 710) and transmission computed tomography (TCAT). ECAT better demonstrates vascular functional i.e. physiologic disturbances. A disadvantage of ECAT is that there is no way to produce survey scans of the head. Relatively long scanning times and moderate spatial resolution when compared with TCAT furthermore reduces the value of ECAT. It is expected that the technical development of ECAT will soon alter the situation.

Adult↗
PubMed1980

Stereotactic biopsy of brain tumors.

Stereotactic biopsies from deep-seated brain tumors were carried out in 302 patients. There were more men (58 percent) than women. Peak of prevalence was in the second to fourth decade; the youngest patient was 18 months old. The tumors were deep-seated hemispheric in 36 percent, in the basal ganglia in 30 percent, in the diencephalic region, i.e., hypothalamus and suprachiasmatic region, in 21 percent, and in the midbrain and pineal region in 13 percent. The majority of lesions were gliomas (71 percent), the remaining being epithelial and various nonglial tumors. Operative mortality was 2.3 percent; transient deterioration was observed in 3 percent. Diagnosis was made instantly by cytological examination (smear preparations) and confirmed by conventional histological examination. In only 5 percent of the gliomas was a discrepancy found between the diagnosis from the smear preparation and the subsequent histological diagnosis. Integrating computerized tomography (CT) imaging techniques into the stereotactic technique makes it possible to take biopsies at exact and reproducible sites and with low risk. The findings suggest that exploratory craniotomies, risky free-hand punctures, and aspirations deep in the brain can no longer be advocated. No radiation treatment should be considered without histological confirmation.

Adenoma↗
PubMed1980

Stereotactic treatment of brain lesions. Biopsy, interstitial radiotherapy (iridium-192 and iodine-125) and drainage procedures.

Integrating CT imaging techniques into stereotactic procedures makes it easy to puncture cysts, take biopsies from neoplastic and nonneoplastic lesions, and place radioactive material in tumors at exact and reproducible sites. A stereotactic program of interstitial radiotherapy in deep-seated brain tumors has been applied in 326 cases as of December 31, 1979 (270 cases using iridium-192 and 56 cases using iodine-125). The use of iodine-125 is now favored since it requires less radiation protection due to its soft 28-35 keV radiation; at the same time, however, it possesses a comparable half life of 60 days. In 126 cases, stereotactic biopsy was used exclusively for diagnostic purposes followed by open craniotomy or conventional radiation. Cystic brain tumors (i.e., craniopharyngiomas and cystic low grade gliomas) were permanently drained by insertion of Rickham reservoir catheters in 61 cases. Stereotactic ventriculocisternostomies were carried out in cases of hydrocephalus and drainage of suprasellar arachnoid cysts was performed in 15 cases. A simple method of projecting CT images onto stereotactic X-ray pictures provides an exact mapping of lesions within the actual stereotactic brain space. The results of this series of patients strongly suggest that exploratory craniotomies and free-hand punctures can no longer be advocated. No radiation treatment should be considered without histological confirmation. The more clearly the volume of a tumor can be defined, the more favorable the results of interstitial irradiation in otherwise unresectable tumors.

Biopsy↗
PubMed1978

Diagnosis of normal-pressure hydrocephalus using CT with CSF enhancement.

Cisternography with the water-soluble contrast medium metrizamide provides substantial advantages for CT demonstration: the discrimination and sharpness of definition of the basal cisterns can be considerably improved by the positive demonstration of the subarachnoid spaces. Studies of CSF dynamics make it possible to differentiate between a communicating hydrocephalus aresorptivus and a hydrocephalus within the scope of a brain atrophy. Brain substance defects and subarachnoid cysts can be clarified with respect to communication with the CSF space. Apart from providing static insights, the cisternographic use of metrizamide through repeated CT examinations also makes it possible to make conclusive statements about CSF dynamics.

Humans↗
PubMed1978

Treatment of small cerebral gliomas with CT-aided stereotaxic curietherapy.

In cases of stereotaxic irradiation of small tumors, CT makes possible a precise determination of tumor volume and dosage and permits exact positioning of the therapy probe. Iridium 192 wires are interstitially implanted in the tumor (mostly gliomas Grades I-III) after biopsy. The results with 98 CT-controlled patients (from a series of 213 implantations in midline tumors) have provided new information about the method of treating small cerebral gliomas.

Brain Neoplasms↗
PubMedDate not supplied

[Stereotaxic diagnosis of brain tumors in childhood as a principle for therapy planning].

Brain tumors of the various histologic types and topographical localization may occur in children. The incidence of brain tumors under the age of 15 years is 2.4-6.5/100,000. Due to the profound physiopathological differences between the various types of cerebral tumors can the choice of the adequate method of treatment not accurately be made without the exact knowledge of the histologic nature. Modern imaging techniques facilitate the visualization of cerebral lesions, do not furnish however a histologic diagnosis. Stereotactic biopsy allows by a direct approach to the lesion--without removal or retraction of healthy brain tissue, as well in the supra--as in the infratentorial space, to establish the histologic diagnosis. This is, together with the topographical localization and the volume, an essential factor for the choice between open surgery, external irradiation (teletherapy), stereotactic interstitial radiation therapy (brachytherapy), stereotactic endocavitary treatment or conservative management.

Adolescent↗