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R V Fisker

Publications and source records attributed to R V Fisker.

6 recordsLinked to original sources

Resistive index: an experimental study of the normal range in the pig.

OBJECTIVES: To study the normal range and distribution of the resistive index (RI) and the resistive index ratio (RIR) in the non-obstructed non-dilated porcine kidney, and to assess the reliability of the threshold values RI 0.70 and RIR 1.10 as prognosticators of true obstruction in the upper urinary tracts. METHODS AND MATERIALS: Twenty female pigs of Danish land race breed were studied under general anaesthesia. Blood pressure and urine output was monitored throughout the experiment. Doppler evaluations were obtained from an interlobar artery in the lower half of each kidney, and the RI was calculated as the average of 3 x 3 cycles for each side independently. Statistical analysis of the obtained results was performed. RESULTS: Forty renal units were studied. The RI values ranged from 0.48-0.85 (mean 0.63). Nine renal units (22.5%) had RI values > or = 0.70. RIR values ranged from 1.00-1.38 (mean 1.07). Three RIR values (15%) were above 1.10. There was no statistically significant relationship between RI and laterality (p = 0.25), and no overall significant relationship between RI and mean arterial blood pressure (r2 = 0.21) or urine output (r2 = 0.004). CONCLUSIONS: This study shows a wide distribution of the RI normal values in the pig model, and our results do not support the normal ranges for RI and RIR, or the cut-off values used in clinical practice.

Animals↗

[Intracranial lipomas].

Intracranial lipomas are rare lesions that should be regarded as congenital malformations. They are usually asymptomatic and incidental findings during neuroradiological investigations. Other brain malformations are often seen in association with intracranial lipomas. The most common is hypoplasia of the corpus callosum. An attempt at surgical removal is not advisable. Lipomas are strongly adherent to the surroundings and typically enclose both vessels and nerves. Magnetic resonance imaging is capable of differentiating lipomas from dermoid cysts and teratomas, making this the diagnostic method of choice.

Adult↗

[Diagnostic possibilities and strategy in the detection of liver metastases].

The value of laboratory tests, scintigraphy, angiography, ultrasonography (US), computed tomography (CT) and magnetic resonance imaging (MR) in the detection of hepatic metastases is evaluated through a review of the literature. The diagnostic value, advantages, disadvantages and limitations of each test are discussed separately. The discussion also includes, economic aspects such as costs, time consumption and examination capacity as well as invasiveness, side-effects, use of contrast medium and patient tolerance. Based on an over-all evaluation, high-quality US combined with US-guided needle biopsy is recommended as the first-choice examination in the detection of liver metastases. In cases of doubt, CT with intravenous contrast and CT-guided biopsy are advisable as a supplement to US. For assessing the effect of treatment, CT is the most suited modality because of its reproducibility. In planning a resection of the liver, detailed information about the localization, size and extent of each lesion is required. Under these circumstances a combination of angiography, CT (or MR) and intraoperative US is to be preferred.

Evaluation Studies as Topic↗

[Spontaneously bleeding renal hemangioma treated by embolization].

Until 1990, a total of 198 cases of renal haemangiomas have been reported; these patients often have to undergo partial or total nephrectomy. We report a case of a 37 year old female admitted with severe haematuria. Selective renal angiography revealed a haemangioma with arteriovenous shunting, situated centrally in her left kidney. Embolization of the artery supplying the shunt was performed with five coils, and four months later isotope renography showed that both kidneys were functioning equally well. The only observed side-effect was mild hypertension.

Adult↗

[Renal vein thrombosis in the neonatal period].

Renal vein thrombosis is a rare disease, which most often occurs in the newborn, in premature babies with complicated deliveries, dehydration, septicaemia or congenital heart defects or in neonates delivered by diabetic mothers. Renal vein thrombosis is due to venous stasis secondary to haemoconcentration or decreased renal perfusion. The typical features are a palpable flank mass, microscopic haematuria, thrombocytopenia, leucocytosis and fever. Ultrasonographic examination shows an enlarged kidney with decreased echogenicity and loss of corticomedullary differentiation combined with hyperechoic streaks throughout the kidney. In Doppler sonography the obstruction of the peripheral veins causes a missing or even negative diastolic flow in the renal arteries. Intravenous pyelography and CT demonstrate missing or delayed excretion in the enlarged kidney. Usually the affected kidney becomes atrophic with calcifications of the renal parenchyma, the renal vein or the inferior vena cava. Therapy is symptomatic. The prognosis is dependent on the extent of the thrombus. In 25% of cases the affected kidney will improve or regain its normal function.

Heparin↗

Hydralazine-induced changes in tissue perfusion and radiation response in a C3H mammary carcinoma and mouse normal tissues.

Hydralazine has been reported to reduce blood perfusion in tumours, thereby increasing hypoxia and subsequently enhancing tumour sensitivity to certain drugs and hyperthermia. We have investigated the ability of hydralazine to induce such changes in a C3H mouse mammary carcinoma and various normal tissues. In tumours, hydralazine (5 mg/kg; i.v.) modified the radiation response, measured by a local tumour control assay, producing an effect equivalent to that seen in tumours made fully hypoxic by clamping. This effect was time-dependent and correlated with the decrease in tissue perfusion estimated by the 86-RbCl extraction procedure. Similar effects were seen in normal skin, although the changes were less dramatic and of a shorter duration. Hydralazine also reduced 86-RbCl uptake in liver, kidney, gut and spleen, but not in bladder, muscle and lung, suggesting that it may have the potential to increase the sensitivity of some normal tissues to hypoxic cell cytotoxins.

Animals↗