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Biomedical subjects

W Bautz

Publications and source records attributed to W Bautz.

At least 91 records · Page 5Linked to original sources
PubMed1998

Experiences with gadodiamide, a non-ionic contrast agent, in MRI of brain metastases.

29 patients suffering from brain metastases were studied with a single (0.1 mmol/kg body weight) and triple dose (0.3 mmol/kg) of gadodiamide, a non-ionic MR contrast agent. The study was performed using an extended imaging protocol with application of T1-weighted images in three orientations. Number of definite and suspected metastases, lesion contrast, edema delineation, and flow artefacts were evaluated. Most of the definite metastases were found in triple dose images. However, the total lesion number could only be determined by looking on all sequences as a whole. Furthermore, the number of suspected metastases could be significantly reduced with triple dose images, but once more all sequences were needed to do so. Flow artefacts were significantly increased by triple dose, whereby lesion contrast and edema delineation was considerably improved. The conclusion is that the combination of high dose application of the contrast agent and an optimized imaging protocol facilitates sufficient imaging of brain metastases. This is important for therapeutical considerations, because patients with more than 1-2 metastases will be treated primarily with radiation therapy instead of neurosurgery.

Brain Neoplasms↗
PubMed1998

[Neuro-MR-findings in primary panhypopituitarism].

Congenital panhypopituitarism is a rare disease. It may be a complication of tumors, craniocerebral trauma, infection, granulomatous diseases, vascular pathologies, etc. In many cases no primary disease causing panhypopituitarism is found (idiopathic form). A potential reason is interruption of the pituitary stalk due to ischemic etiology in patients with cord encirclement and/or other birth injuries leading to interruption of the axonal transport of ADH and oxytocin as well as hypothalamic releasing hormones. This explains the ectopy of the neurohypophysis without diabetes insipidus and the hypoplasia of the adenohypophysis. GH-deficiency causes short stature and metabolic disturbances, LH-FSH-deficiency amenorrhoea/oligomenorrhoea, loss of libido and secondary sexual characteristics, TRH-deficiency hypothyroidism and ACTH-deficiency hypotonia, weakness, loss of pigmentation. We report a case of congenital panhypopituitarism. MR imaging of the brain revealed a hypoplastic adenohypophysis and a hypoplastic pituitary stalk which was interrupted in its superior segment. An ectopic neurohypophysis was found located in the area of the hypothalamus ("hypothalamic hot spot"). The ectopic neurohypophysis showed strong enhancement after intravenous application of Gd-DTPA. MR imaging of the hypothalamic-hypophyseal axis is well suited for the differentiation between congenital and acquired forms of panhypopituitarism in clinically uncertain cases.

Adult↗
PubMed1998

[Interventional methods in breast diagnosis. Histological vs. cytological evaluation of core cut biopsies of the breast].

High speed core cut biopsies of breast tumors, sonographically or stereotactically guided, allow an histological examination of the tumor without surgery. It can be used prior to operation for the confirmation of a breast cancer and it can avoid unnecessary breast surgery in benign tumors. Unfortunately, only some centers are equipped with a pathology unit that allows an immediate histological examination. But often these institutes are provided with an experienced cystologist. Thus, the question arises if a cytology taken from the core cut biopsy is as reliable as an histological examination. In a prospective study we performed unroll-cytologies in core cut biopsies of 173 breast tumors in 169 patients consisting of 122 malignant and 51 benign tumors. Histology of core cut biopsies was proven by operational histology in all malignant and in 5 benign tumors. Histology of core cut biopsies could not be judged in 2 cases (lymphoma, gallert carcinoma). Cytological slide preparations were technically inadequate in 4 cases. The false negative rate of histology was 1/120 and 27/120 in cytology. Histology compared with cytology showed the following results: sensitivity 99.2% versus 77.5%, specificity 100% versus 95.9%, positive predictive value: 100% vs. 97.8%, negative predictive value: 98.1% vs. 63.5%, and accuracy: 99.4% vs. 82.8%. The sensitivity of cytology was much worse than that of histology of core cut biopsies. Thus, in our opinion cytology can provide a quick diagnostic orientation, but it cannot replace the more reliable histological examination. Diagnostic or therapeutic decisions should be based upon the more reliable histological results.

Biopsy↗
PubMed1997

Pulmonary nodule caused by an alveolar adenoma of the lung.

Alveolar adenomas of the lung may be a rare cause of solitary coin lesions on chest radiographs. We report a case of this neoplasm, describe its morphological and immunohistochemical characteristics and give further evidence that alveolar adenomas of the lung represent a benign proliferation of both the alveolar epithelium and the septal mesenchyme.

Adenoma↗
PubMed1997

Imaging and staging of avascular osteonecroses at the wrist and hand.

Avascular ostenecroses (AVN) are unspecific focal sceletal lesions of vascular origin. At the wrist, AVNs are mainly seen in the lunate (Kienbock's disease) and the proximal scaphoid fragment in the presence of a nonunion disease (pseudarthrosis). Other types of osteonecroses are rare. The natural process of devitalization proceeds in steps: initially, there is a bone marrow oedema, followed by trabecula sclerosis, cystic transformation of the spongiosa, and bone fragmentation. End stages include carpal collapse (SLAC wrist) and osteoarthritis. For imaging of the sceletal morphology in AVN computed tomography is most useful, whereas initial stages and perfusion damages are better detected with contrast enhanced magnetic resonance imaging (MRI). In this paper a staging classification for Kienböck's disease and the scaphoid nonunion, considering the diagnostic and therapeutic consequences, is presented.

Diagnosis, Differential↗
PubMed1996

Anatomic variants of the spermatic vein: importance for percutaneous sclerotherapy of idiopathic varicocele.

PURPOSE: To evaluate percutaneous sclerotherapy of idiopathic varicocele in left internal spermatic vein variants. MATERIALS AND METHODS: The left spermatic vein was embolized with a liquid sclerosing agent in 386 patients (mean age, 29.5 years) with idiopathic varicocele. Success and complication rates were assessed and correlated with spermatic vein variant. Doppler ultrasound was performed 3 and 6 months after therapy in 263 patients. RESULTS: The success rate was 93.8% (n = 362). Perforation of the vein was the most common complication (n = 24). The recurrence rate was 3.8% (10 of 263 patients). Success and complication rates were associated with spermatic vein variant. Type IVb (intact valve of the main trunk, insufficient collateral vessels; n = 73) was of special importance: 67% (16 of 24) of all perforations occurred and 54% (13 of 24) of all unsuccessful interventional procedures were performed in patients with this variant. CONCLUSION: Sclerotherapy is a safe and effective alternative treatment of idiopathic varicocele. It can be performed on an outpatient basis. Success depends on the anatomic variant.

Adult↗
PubMed1995

[Pyrimethamine-sulfadiazine resistant cerebral toxoplasmosis in AIDS].

A 48-year-old man with known HIV infection for 4 years was admitted with a 2-week history of increasing brachio-facial paraesthesiae of the left side of the body and pains in the head and neck. Physical examination also showed discrete slowing of mental activity and oral candidiasis. Toxoplasmosis serology showed a low titre with a borderline IgM titre. Cranial computer tomography showed two confluent contrast medium concentrating foci in the region of the head of the caudate nucleus and the right internal capsule. Because toxoplasmosis encephalitis was suspected, treatment was started with sulfadiazine (1 g four times daily), pyrimethamine (25 mg four times daily), folic acid (15 mg daily) and dexamethasone (8 mg three times daily). After 19 days of treatment there was no clinical improvement, and a check CT scan showed worsening with increased oedema of the cerebellar medulla, compression of the lateral ventricles and a mid-line shift of 5 mm. Since the Sabin-Feldman test titre had increased, and there was no evidence to suggest a lymphoma or a viral or fungal infection, toxoplasmosis resistant to standard therapy was postulated, and treatment was started with clindamycin (600 mg three times daily) and pyrimethamine (25 mg four times daily). The clinical features subsided within 4 days. A further check CT scan 14 days later showed almost complete resolution.

AIDS-Related Opportunistic Infections↗
PubMed1995

[Volumetry of abdominal tumors. Problems--feasibility].

If multimodal tumor therapy in the abdomen is to be effective, exact staging is required for which one needs precise planimetric and volumetric data. The most important indication for clinically reliable volumetric determination of tumor size in the abdominal region is monitoring liver metastases during chemotherapy. Determination of volume can be effectively realized using 3D reconstruction. Therefore, the primary data set must be complete and contiguous. The mass should be depicted strongly enhanced and free of artifacts. At present, this prerequisite can only be complied with using thin-slice spiral CT. Phantom studies have proven that a semiautomatic reconstruction algorithm is recommendable. The basic difficulties involved in volumetric determination of tumor size are the problems in differentiating active malignant mass and changes in the surrounding tissue, as well as the lack of histomorphological correlation. Possible indications for volumetry of gastrointestinal masses in the assessment of neoadjuvant therapeutic concepts are under scientific evaluation.

Abdominal Neoplasms↗