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Biomedical subjects

D Petersen

Publications and source records attributed to D Petersen.

At least 109 records · Page 6Linked to original sources
PubMed1988

[Neuroblastoma of the olfactory nerve. Radiotherapy experiences in 6 patients].

Six patients with neuroblastomas of the olfactory nerve (esthesioneuroblastoma) are presented who were irradiated between 1983 and 1986 at the Medical Radiologic Institute of Tübingen. Clinical manifestations, diagnostics, histology, therapy, and courses are compared and discussed with regard to a survey of literature. An attempt is made to find out the value of radiotherapy in the treatment of this rare disease. In stage A (tumor restricted to the nasal cavity, 1 patient), a local tumor control of up to now 28 months could be achieved by a treatment combination of surgery and radiotherapy. A treatment consisting of surgery or radiotherapy alone should even in this stage only be performed in connection with a close follow-up because of the increased local recurrence risk. Tumors of stage B (manifestation in the nasal cavity and the paranasal sinuses) did not occur in this group of patients. Five patients suffered from tumors of stage C (tumor extent beyond the paranasal sinuses). A good palliative effect was obtained temporarily by radiotherapy alone in three out of these patients showing large inoperable tumors and rapidly progressing clinical symptoms. A complete remission now lasting 16 months was achieved only in one patient by radical surgery with unilateral evisceration of orbit and homogeneous postirradiation. In case of stage C tumors it is recommended to perform, if possible, a radical tumor excision with evisceration of orbit in case of unilateral manifestation in the orbit and a postirradiation applying a radical, large volume technique. In order to reduce the risk of radiogenic cerebral necroses, it should be attempted to avoid dose maxima as they can occur when applying a combined ventro-dorsal and lateral irradiation technique.

Adult↗
PubMed1988

[Cerebral tuberculoma in pregnancy].

Intracranial tuberculomas today are rare in industrialized countries. We report the case of a 29 year old female German patient who in the sixth month of her pregnancy presented with epilepsy and mild hemiparesis. Cranial CT showed a parietal contrast-enhancing lesion. Mediastinal tuberculosis was confirmed by biopsy. Both the mediastinal and the cerebral lesion together with the neurological signs resolved under therapy with antituberculous drugs, and the patient gave birth to a healthy child.

Adult↗
PubMed1987

Pseudotumor cerebri: clinical and neuroradiological findings.

Pseudotumor cerebri (PTC) is a diagnosis per exclusionem applied to a condition of increased intracranial pressure in the absence of an intracranial infection, a space-occupying lesion, or hydrocephalus. Diagnostic criteria should include the evaluation of possibly disturbed cerebral venous outflow, which may result in similar clinical findings. Disturbed venous drainage should be separated from the syndrome of PTC because it represents a condition of well-defined origin and therapeutic regimen. Course and prognosis of PTC are not related to the increased intracranial pressure, the degree of papilledema, or to the duration of the disease. Functional cerebral disorders and EEG abnormalities are rare, indicating that brain tissue is not primarily affected. Correspondingly, computerized tomography (CT) scans with respect to the cerebrum are normal in about 90% of the cases; but enlarged optic nerve sheaths (46.7%) and empty sella (45.7%) are frequent findings on CT-scans. They most likely represent a direct consequence of long-term increased pressure within CSF spaces. This observation favors the assumption of disturbed CSF-pressure regulation either by increased production of CSF or its decreased rate of absorption. Brain edema (slit ventricles) as assessed by CT is a rare finding (11.4% of our cases). It may be a hint towards a different pathogenetic entity.

Adult↗
PubMed1987

Indium-111 platelet scintigraphy and two-dimensional echocardiography for detection of left ventricular thrombus: influence of clot size and age.

Two-dimensional echocardiography and indium-111 platelet scintigraphy were performed on 50 dogs to determine the influence of clot age and size on the detection of experimentally induced left ventricular mural thrombus. Thrombus was induced by apical infarction and injection of a sclerosing agent and thrombin. The animals were classified into four groups according to the time of indium-111 platelet injection after thrombus induction: Group I (17 dogs, 1/2 hour after induction; 3 dogs, before induction), Group II (12 dogs, 24 hours after induction) and Group III (12 dogs, 1 week after induction). In Group IV (six control dogs) apical infarction was produced, but thrombin was not injected; indium-111 platelets were injected 1/2 to 1 hour after infarction. The dogs were studied by indium-111 platelet scintigraphy and by two-dimensional echocardiography 1/2 to 5 hours (Group I) and 1 to 5 and up to 72 hours (Groups II to IV) after platelet administration and before death was induced. Two-dimensional echocardiography showed the best overall sensitivity for detection of acute thrombus (97%; 29 of 30). The sensitivity of indium-111 platelet scintigraphy was 86% (18 of 21) for clots greater than or equal to 0.08 ml in size, and 67% (20 of 30) for detection of all clots. Thrombus did not form in 14 dogs of Groups I to III and in 6 of 6 control dogs. The specificity of scintigraphy was 100% (20 of 20) compared with 80% (16 of 20) for echocardiography. Echocardiography was more sensitive than scintigraphy for detecting very small clots in this experimental model.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Platelets↗
PubMed1987

[Cystic teratoma of the orbit].

Teratomas are rare cystic tumors of the orbit which lead to excessive congenital exophthalmos. They increase rapidly in size after birth and therefore require immediate surgical treatment. Initial puncture of the cyst under sonographic control prevents progressive mechanical damage to the globe and the optic nerve, providing sufficient time for the preoperative measures required prior to final surgical removal. The characteristic clinical features make it easy to identify a teratoma provided it has been taken into consideration in the differential diagnosis. It is shown with reference to one of the authors' own cases that a good functional result is possible after removal of the encapsulated tumor with preservation of the globe, even when the eye has been excessively displaced by the tumor.

Dermoid Cyst↗
PubMed1987

Antithrombin III (ATIII) activity in plasmas from normal and diseased horses, and in normal canine, bovine and human plasmas.

Plasma Antithrombin III (ATIII) activity was quantitated in 24 clinically normal Standardbred/Thoroughbred horses using a clotting time technique. ATIII activity ranged from 80 to 106% of the pooled reference standard plasma, with a mean of 94%. Horses presenting with impaction or spasmotic colic (n=17) had normal plasma ATIII activity, while 15 horses presenting with acute diarrhea/colitis had significantly lower plasma ATIII activity with a mean of only 74% of the reference plasma. Seven horses presenting with liver disease had significantly higher plasma ATIII activity with a range of 127 to 177% of the pooled reference plasma. Fifty-seven equine plasmas were retested using a rapid chromogenic substrate technique for quantitating plasma ATIII activity. A good correlation (r =+0.83) existed between clotting time and chromogenic determinations of ATIII. Pooled normal canine, human and bovine plasmas had only 65, 62 and 79%, respectively, of the ATIII activity of the equine reference plasma.

Journal Article↗
PubMed1987

[3-dimensional (3-D) image reconstruction of the facial skull and skull base in computerized tomography].

The diagnostic value of three-dimensional (3-D) image reconstruction in conditions affecting the craniofacial skeleton and the skull base has been assessed and the results compared with the CT scans used. Owing to reconstruction artefacts and some limitations in the exact display of 3-D images, no substantial improvement in diagnosis can be expected. Nonetheless, 3-D images facilitate the analysis and detection of complex fractures of the craniofacial skeleton and improve surgical planning and postoperative evaluation.

Facial Bones↗
PubMed1987

[Otogenic extradural pneumatocele, 36 years after a gunshot injury].

In the reported case an extradural pneumatocele developed 36 years after the mastoid tip had been destroyed by a bullet. It had reached the occiput and led to destruction of the bone surrounding its distal end, so that air could be found directly under the galea. In the literature there are only few case reports referring the otogenic origin of a posttraumatic extradural pneumatocele. Furthermore, an overpressure in the middle ear cleft or mastoid could be excluded because of the presence of a tympanic membrane perforation. In spite of a chronically infected middle ear, there was no infection of the pneumatocele.

Deafness↗
PubMed1986

[Comparison of clinical findings and nuclear magnetic resonance tomography in syringohydromyelia and intramedullary tumors].

Magnetic resonance imaging allowed a distinct differentiation between syringohydromyelia (9 patients) and intramedullary tumour (2 patients). In syringohydromyelia the morphological evaluation showed a greater extension of the cavitation, especially in the caudal direction, than the estimation according to clinical findings. Tumours were visualised indirectly by changing the physiological shape of the spinal cord; therefore, small parts were not recognisable on magnetic resonance images but detected by the corresponding clinical symptoms. Clinical and morphological data were complementary and both necessary for a comprehensive appreciation of the pathological process.

Adolescent↗
PubMed1985

Magnetic resonance and CT imaging of diastematomyelia.

The clinical, MRI and CT features of diastematomyelia with an uncommon clinical course are reported. Possible pathogenetic aspects in the late onset of symptoms are discussed implying vascular factors. MRI provides direct visualization of the split cord and low conus, confirming that frontal images are preferable.

Adult↗