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S Dorph

Publications and source records attributed to S Dorph.

87 records · Page 5Linked to original sources

Evaluation of treatment response in active Crohn's disease by low-field magnetic resonance imaging.

BACKGROUND: To evaluate low-field magnetic resonance imaging (MRI) in detecting therapeutic response in active Crohn's disease during treatment with systemic steroids. METHODS: Eight patients with active Crohn's disease were examined before and during treatment with systemic steroids (1 mg/kg/day) using low-field MRI (0.1 T) in transverse and coronal planes before and after an intravenously administered bolus of gadodiamide. Five healthy persons were once examined in the same way. MRI images were evaluated without knowledge of diagnosis, treatment, or findings of endoscopy, conventional radiography, and surgery. Proximal and mid small bowel, terminal ileum, right-sided colon, transverse colon, and left-sided colon were evaluated separately. RESULTS: Statistically significant differences were shown for both signal intensity on T2- (SIT2) and increment in signal intensity on T1-weighted images after contrast (%SIT1) when comparing diseased bowel segments with both nondiseased bowel segments (SIT2: p = 0.0001; %SIT1: p = 0.0009) and segments from the control group (SIT2: p < 0.00005; %SIT1: p < 0.00005). In 53 of 56 bowel segments evaluated (95%), agreement was found between findings by MRI, conventional radiography, endoscopy and/or surgery regarding disease extension. Extension was underestimated in two patients. All bowel segments in the control subjects were evaluated to be normal on MRI. Significant correlation was found between both SIT1 (p < 0.0025) and %SIT1 (p < 0.025) versus endoscopic activity gradings. During treatment, significant decrements of both SIT2 (p < 0.00005), %SIT1 (p = 0.002), and bowel wall thickness (p = 0.03) were found. CONCLUSIONS: Low-field MRI seems to be a promising noninvasive method in the evaluation of response regarding both disease extension and activity in Crohn's disease during treatment with systemic steroids.

Adult↗

Why does kidney size change during I.V. urography?

Meglumine iothalamate (280 ml I/ml) and sodium iothalamate (400 mg I/ml) in doses of 700 mg I/kg bw, were injected i.v. as a bolus in dogs. Renal size, urine flow rate, arterial pressure, renal blood flow and mean transit time and renal blood volume were measured before and after injection. All changes were qualitatively and quantitatively identical for both drugs. They produced a small transient renal shrinkage followed by a greater and prolonged renal enlargement. During the period of renal enlargement, urine flow increased. The time course of the enlargement paralleled the increase of urine flow rate. Renal blood flow also increased but both the mean transit time and renal vascular volume decreased. Therefore, the kidney size increase after i.v. injection of large doses of urographic contrast media cannot be attributed to an increased volume of the vessels. Most likely it is caused by diuresis-induced increase in the volume of the tubules.

Animals↗

Pyelorenal backflow in normal and ischemic rabbit kidneys.

Pyelorenal backflow during retrograde pyelography was studied in 68 kidneys of anesthetized rabbits. Thirty-three of the experiments were performed during or shortly after temporary renal arterial clamping. Pyelosinous backflow was observed in 67 and pyelovenous backflow in 65 of the 68 kidneys, occurring at an average intrapelvic pressure of 70 mmHg. This was true in intact kidneys and during arterial occlusion. Intrarenal backflow--intrusion of contrast material into the renal parenchyma--could be produced in only one of 35 experiments on intact kidneys, and occurred at an intrapelvic pressure of 119 mmHg. During arterial clamping, intrarenal backflow was observed in eight of nine experiments, occurring at intrapelvic pressures of about 70 mmHg. After removal of the clamp, intrarenal backflow was less frequent with shorter periods of arterial clamping and longer time between restoration of arterial flow before pyelography. Subcapsular extravasation of the medium with total blurring of the kidneys shadow and a prompt fall in intrapelvic pressure was the ultimate result of prolonged and extreme overdistension of the renal pelvis. It occurred at an average intrapelvic pressure of 80 mmHg. Histologic examination revealed tears in the fornix of the pelvic cavity in cases with pyelosinous backflow. If intrarenal backflow was present, there were tears leading from the pelvic cavity into the renal parenchyma. Supplementary experiments using a contrast material that could be demonstrated histologically (barium sulfate with gelatin) showed that the contrast filled the intertubular capillaries and venules. There was no evidence of backflow through the canalicular route.

Animals↗

The transplanted kidney. Diagnostic and interventional radiology.

Following kidney allotransplantation a great number of complications threaten the patient and his graft, e.g. acute tubular necrosis, acute and chronic rejection, urologic and vascular complications and complications due to the immunosuppressive treatment. During the last decade a number of technical developments in radionuclide, ultrasonographic and radiographic imaging and intervention has significantly improved the possibility of early recognition and handling of such complications. Knowledge of the capability and limitations of the various techniques is of vital importance for their rational use. The aim of this review article is to give a short description of the various imaging modalities, the rational monitoring of the posttransplant patient, and possible handling of complications by the aid of imaging techniques.

Angiography↗

Caliceal clubbing and adjacent parenchymal scarring (always reflux nephropathy?) as a cause of end-stage renal failure.

Various clinical and laboratory aspects in 15 kidney transplanted patients with urographic evidence of caliceal clubbing and adjacent parenchymal scarring in their native kidneys are reported. These lesions were found in 16 per cent of our series of kidney transplantations; below 35 years of age it was the second most frequent disease. In 9 of these patients severe vesicoureteral reflux had been demonstrated. In the remaining 6 patients reflux nephropathy was only a tentative diagnosis based on a striking similarity in the radiographs and in several clinical findings. Nine patients had symptoms (mainly related to urinary tract infection) from 1 to 17 years before diagnosis/urography, in 5 as early as the first year of life. Recurrent urinary tract infection and renal impairment were the most frequent disorders leading to the diagnosis. Replacement therapy was initiated at an average age of 32.7 years. Following renal transplantation urinary tract infection was documented in 37 per cent of patients whether the patient had been bilaterally nephrectomized or not.

Adult↗

The vestibular aqueduct in Meniere's disease.

The vestibular aquaeduct was evaluated blindly in tomograms from patients with Meniere's disease or chronic otitis and from patients without ear disorders. The descending part of the aquaeduct was clearly visible in 95% of the patients without ear disease. In the two other groups, it was visible only in about 50%. It is suggested that a narrow or invisible vestibular aquaeduct is an unspecific radiological sign in a variety of ear diseases.

Adolescent↗

Effect of glucagon-(1-21)-peptide on gastroduodenal motility during upper gastrointestinal examination. Randomized trials.

The inhibitory effect of glucagon-(1-21)-peptide on the motility of the stomach and duodenum during radiologic double contrast studies was examined. In a randomized trial of equimolar doses of glucagon and glucagon-(1-21)-peptide on 70 patients, glucagon-(1-21)-peptide showed to have a significantly weaker effect than glucagon. Glucagon caused significant increases in plasma-glucose and plasma-insulin, while glucagon-(1-21)-peptide had no such effects. In a subsequent randomized study on 75 patients glucagon-(1-21)-peptide in various doses was tested against placebo. The effect was insignificant from that of placebo at practically all dose levels. No side effects were registered. It is concluded, that glucagon-(1-21)-peptide probably has a certain relaxing effect on the smooth muscle of the stomach and duodenum, but that this effect is too small for practical clinical use.

Adult↗

Effects on urine profiles of diatrizoate in hydrated and dehydrated rats. A double cross-over study.

Effects of intravenous diatrizoate on urine profiles in hydrated and dehydrated rats were compared. In 12 normal rats albumin, glucose, sodium, and the enzymes LDH and GGT were followed twice over 3 hours. The 6 rats being dehydrated at the first examination were hydrated 28 days later and vice versa. At both examinations diatrizoate affected all profile components significantly during the first two hours and caused a 3 per cent weight loss in both groups. Only one significant difference between the hydrated and dehydrated rats was found: The excretion of the brush border enzyme GGT was 1.5 times higher in the dehydrated than in the hydrated rats in both series. Thus, the effect of diatrizoate on the tubular brush border seems to depend on the state of hydration in normal rats.

Albuminuria↗

Artificial urinary sphincters. Radiographic evaluation.

A small selected group of patients with urinary incontinence can be treated effectively with an artificial urinary sphincter. Since the fluid in the hydraulic system of this device is radiopaque, radiography is useful in its evaluation. An immediate postoperative radiogram should be performed to control the position and integrity of the system. It also serves as a useful baseline study in case of later complications. It should include radiograms both in the deactivated and activated state. A few cases of tube kinking may be overlooked when exposures in only one projection are used. Experience with 110 implanted sphincters is presented.

Adolescent↗

The upper urinary tract. Pyelography and interventional procedures.

Pyelography is superior to all other imaging techniques for the demonstration of fine detail in the pelveocalyceal system and the ureter. For almost 90 years it has been performed through a retrogradely inserted catheter, but during the recent 30 years antegrade injection via a transparenchymally inserted needle or catheter has become an accepted alternative, especially in case of a dilated upper urinary tract. Both methods have their advantages and their disadvantages. This article presents a review of indications, techniques, and complications. Furthermore, interventional procedures on the upper urinary tract--such as stent placement and balloon dilatation--are now handled by the radiologist, mainly through an antegrade approach. These therapeutic procedures are also reviewed.

Humans↗

Intravenous injection of ioxilan, iohexol and diatrizoate. Effects on urine profiles in the rat.

Effects of intravenous ioxilan, a new third generation non-ionic contrast medium, diatrizoate, iohexol and saline on urine profiles were compared. Albumin, glucose, sodium, phosphate, and the enzymes NAG, LDH and GGT were followed in 24 normal rats over 7 days. Diatrizoate significantly affected all profile components during the first two hours. Albuminuria was significantly greater after diatrizoate than after iohexol or ioxilan, and excretion of glucose, LDH and GGT was significantly higher than after ioxilan. Both iohexol and ioxilan increased the excretion of albumin, LDH and GGT, while iohexol also significantly increased excretion of glucose and sodium. There was a greater excretion of glucose and GGT after iohexol than after ioxilan. Saline did not induce any changes. At day 7, serum sodium, urea, creatinine, and albumin were normal for all test substances, and kidney histology revealed no difference between the groups of animals. It is thus concluded that both high osmolar ionic and low osmolar non-ionic contrast media may cause temporary glomerular and tubular dysfunction in rats. In this model, the kidney is affected most by diatrizoate, less by iohexol, and least by ioxilan.

Animals↗

Reliability of voiding colpo-cysto-urethrography in female urinary stress incontinence before and after treatment.

Voiding colpo-cysto-urethrography was performed in 52 consecutive female patients with genuine urinary stress incontinence before treatment and in 50 of the patients after treatment. The patients were randomized to either pelvic floor training or surgery. Surgery included a colposuspension operation in patients with an anterior suspension defect and a vaginal repair in patients with a posterior suspension defect. All pre- and posttreatment examinations were reevaluated blindly by one observer 4 to 6 years later. The pretreatment radiologic reevaluation was in agreement with the original classification in 79 per cent and not in agreement in 21 per cent. Pelvic floor training did not change the degree of suspension defect systematically. The effect of squeezing was significantly improved following pelvic floor training. A colposuspension gave rise to a typical radiologic configuration of the bladder and urethra. A vaginal repair was not detectable radiologically and it did not correct a posterior descent. The degree of descent and the degree of incontinence were not correlated and it was not possible radiologically to distinguish treatment failures from treatment success.

Adult↗

Effects of intravenous injection of diatrizoate, iohexol or ioxilan on renal size, urine profiles and blood profiles in the rabbit.

Diatrizoate, iohexol or ioxilan were injected intravenously in 18 rabbits. The contrast medium passage through the kidneys was recorded on digital subtraction images for the first 50 s followed by 100 mm exposures up to 15 min after injection. The renal area was measured planimetrically. Urine profiles (glucose, phosphate, LDH, GGT, NAG), blood profiles (potassium, urea) and the relative clearance of albumin and sodium were followed for 5 days and compared with a control group injected with saline. All kidneys were examined by light and immunofluorescence microscopy. All three contrast media produced excellent arteriograms and urograms. The three different contrast media caused a rapid increase of the kidney area within the first minute, reaching an average maximum of 10 to 12 per cent after 5 min, followed by a gradual decline. Contrary to expectations the increase in renal area was similar for all three contrast media, so hyperosmolality is no likely explanation of this phenomenon. None of the contrast agents caused significant changes in any of the profile components with one exception: the GGT excretion was significantly elevated during the first 24 h after diatrizoate administration as compared with the effect of saline. Light and immunofluorescence microscopy revealed no differences.

Animals↗