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Biomedical subjects

M Rothmund

Publications and source records attributed to M Rothmund.

At least 109 records · Page 6Linked to original sources
PubMed1997

[Development of a thyroid carcinoma after irradiation of the head/neck region].

HISTORY AND CLINICAL FINDINGS: A 73-year-old woman was hospitalised because of increasing dyspnoea and hoarseness after a bout of acute tracheobronchitis. She had been receiving levothyroxine for a growing grade III nodular goitre. At the ages of 26 and 29 she had been treated for cervical lymph node tuberculosis with local excision and percutaneous radiotherapy of 8 Gy each time. On examination she was found to have a bulging neck profile and a hard, practically immobile node in the left lobe of the thyroid. INVESTIGATIONS: Laboratory tests showed a euthyroid metabolic state, while ultrasound demonstrated a mass. 40 mm in diameter, scintigraphically a cold nodule. A fine-needle biopsy was cytologically highly suspicious of neoplasm. TREATMENT AND COURSE: Surgical exploration of the neck and mediastinum revealed an insular follicular carcinoma (10 cm in diameter), involving the right recurrent laryngeal nerve and surrounding the brachiocephalic trunk. The latter had to be removed and a Gore-Tex graft was interposed. Postoperative radiotherapy was given (150 mCurie I131). CONCLUSION: An enlarging nodular goitre, occurring after a latent period of years following radiotherapy to the neck region for benign and (or) malignant disease, especially when it had been administered in childhood or young adulthood, should raise the suspicion of a radiogenic thyroid carcinoma. Definitive diagnosis by fine-needle biopsy is essential.

Adenocarcinoma, Follicular↗
PubMed1997

Antiproliferative effect of suramin on primary cultures of human pheochromocytomas and rat PC12 pheochromocytoma cells.

BACKGROUND: Suramin inhibits growth of neural crest-derived cells and is used to treat adrenocortical cancer and neuroblastoma in clinical trials. The antiproliferative effect of suramin was evaluated in primary cultures of human pheochromocytoma and the PC12 rat pheochromocytoma cell line in vitro and in vivo. METHODS: Human pheochromocytoma and PC12 rat pheochromocytoma cells were grown in medium supplemented with suramin at concentrations of 1-1,000 micrograms/ml (1.43-1.43 mM) for up to five generations. Suramin did not induce neuronal differentiation, but inhibited growth of cultured human pheochromocytoma cells with IC50 (inhibitory concentration at which a 50% reduction of proliferation is observed) of 50-250 micrograms/ml. Also, suramin inhibited proliferation of PC12 cells with IC50 of 228 micrograms/ml after 5 days and 161 micrograms/ml at 10 days of treatment. Colony formation assays demonstrated these effects to be cytotoxic rather than cytostatic. Thus when reproductive integrity of PC12 cells was taken into account, IC50 was calculated with 118 micrograms/ml and 129 micrograms/ml, respectively. In vivo experiments were performed with subcutaneously xenotransplanted PC12 cells (BALB/c NCR-NU mice). Suramin did not alter tumorigenicity and did not inhibit local tumor growth. RESULTS: These data determine for the first time an antiproliferative effect of suramin in pheochromocytoma cells. Suramin is cytotoxic to pheochromocytoma cells in vitro at levels that are clinically achievable. CONCLUSIONS: Suramin may have potential as an antiproliferative drug in nonresectable pheochromocytoma.

Adrenal Gland Neoplasms↗
PubMed1997

[Laparoscopic adrenal gland surgery].

Minimally invasive adrenalectomy is now an accepted alternative to conventional adrenalectomy. As in open surgery, several different endoscopic approaches to the adrenal glands have been described. In principle, one must distinguish between the laparoscopic and the retroperitoneoscopic access. All adrenal tumors--pheochromocytomas included--except adrenal carcinomas can be removed endoscopically. However, the use of these techniques is limited in patients with particularly large tumors. The results reported to date are convincing. Only limited data are available as yet to compare conventional and endoscopic adrenalectomy. Because adrenal diseases requiring surgery are rare, endoscopic adrenalectomy is an operation that, for the present, will be limited to centers with a particular interest in laparoscopic and endocrine surgery.

Adrenal Gland Neoplasms↗
PubMed1997

[Intraoperative cholangiography as a routine method? A prospective, controlled, randomized study].

A prospective, controlled, randomized trial was conducted in 275 patients with symptomatic gall stone disease, whose history, laboratory data or sonographical findings did not suggest common bile duct stones. Of these patients, 137 did not undergo intraoperative fluoroscopic cholangiography (IOC), but in the remaining 138 patients IOC was attempted. In 111 cases (80.4%) the biliary system was sufficiently visualized. In 3 patients (2.7%) calculi in the cystic or common bile duct were diagnosed, which would have been overlooked without IOC. IOC was false-positive in one case. One year after the operation the patients were asked to return for a follow-up examination. Three patients in the group without IOC had had symptomatic passage of a stone, and one had a common bile duct stone removed by endoscopic papillotomy. A retained stone was discussed as etiology for a pancreatitis in a fifth patient in this group. No patient sustained long-term sequelae from the retained common bile duct stones. None of the patients in the IOC group had evidence of cholangiolithiasis at follow-up. There was no difference between the study groups concerning the incidence of post-operative complications. The operations with IOC lasted significantly longer (92 +/- 31 min vs 77 +/- 28 min). According to our data and those published earlier, the additional financial and logistic expenditure associated with routine IOC is not justified. Patients with the preoperative suspicion of a common bile duct stone should have endoscopic bile duct clearance (ERCP and EPT) prior to cholecystectomy.

Adult↗
PubMed1997

[The longitudinal muscle of the anal canal].

The longitudinal muscle (LM) represents a strong muscular structure of the anal canal situated between the internal (IAS) and the external anal sphincter (EAS). Terminal fibres of this muscle insert at the submucosa of the anal canal, representing the m. canalis ani. Others cross the subcutaneous part of the EAS to become the m. corrugator ani. Thus, the LM connects the visceral and somatic parts of the anal sphincter complex. Histologically ganglionic cells and as Vater-Pacinian corpuscles can be identified inside the LM. Morphology, topography and histology of the LM suggest that this muscle participates in maintaining anorectal continence. It is mandatory that the exact functions of this muscular structure be to elaborated upon, if we are to understand the mechanism of anorectal continence.

Anal Canal↗
PubMed1997

"Surgical" ultrasound in suspected acute appendicitis.

BACKGROUND: Ultrasonography (US) by acknowledged experts enhances the diagnostic performance and reduces the rate of negative laparotomies in patients with suspected acute appendicitis (AA). METHODS: The diagnostic accuracy and clinical impact of routine US performed by surgical residents was prospectively studied in 504 unselected patients admitted for AA. Clinical and US findings were correlated with laparotomy findings and pathological outcome in 135 patients (113 cases with proven AA, prevalence 22.4%) and clinical as well as follow-up data were compared in the remainder. RESULTS: The overall accuracy, sensitivity, and specificity of the clinical diagnosis of AA were 84.9%, 51.3%, and 94.6% and those of US were 93. 6%, 83.1%, and 96.6%. Joint evaluation of the results from clinical evaluation and US further improved diagnostic performance (accuracy 93.4%, sensitivity 84.1%, specificity 96.2) and significantly reduced the rate of diagnostic errors to 3.4% (p < 0.001) and unnecessary laparotomies to 9.6% (p < 0.01) in patients with suspected AA. CONCLUSIONS: Ultrasonographic evaluation of the patient with suspected AA is considered to be of value in surgical practice.

Acute Disease↗
PubMed1997

Diagnostic ultrasound of acute colonic diverticulitis by surgical residents.

BACKGROUND: Recent studies have documented the feasibility of ultrasonography (US) to diagnose acute colonic diverticulitis (ACD). This prospective observational trial determined the sonomorphology of ACD and evaluated the diagnostic accuracy of routine US performed on admission by surgeons in training. METHODS: Fifty-seven consecutive patients with a confirmed episode of ACD were entered into this study, and the sonomorphology of the involved colon was assessed. US findings were compared to the results of the clinical evaluation and correlated to the clinicopathological outcome. RESULTS: The sonomorphology of ACD was characterized by segmental inflammatory transformation of the colon averaging 9.9 +/- 3.2 cm (range, 6-20) in length and visualized as target phenomena of a mean 3.5 +/- 0.8 cm (range, 2.4-4.8) width. Targets were caused by hypoechogenic thickening of the colonic wall of an average 7.7 +/- 2. 6 mm (range, 4-18). In 40% of cases, a hyperechogenic halo representing peridiverticulitis (average width, 2.3 +/- 0.6; range, 1.2-3 cm) was noted. Diverticula were seen in almost half of the cases. Of the 57 cases with confirmed ACD, the diagnosis was made by US in 48, for a global accuracy of 84.2%. US was false negative in nine patients, suggesting perforated appendicitis in five cases and acute appendicitis in one (the final diagnoses were perforated sigmoid diverticulitis in five cases and cecal diverticulitis in one case). In three patients, US was nondiagnostic. CONCLUSION: In the hands of sonographically trained surgeons, ultrasound is a useful modality to image acute colonic diverticulitis. US reveals diagnostic sonomorphology in most cases of ACD and therefore facilitates early confirmation of the diagnosis and assessment of severity.

Acute Disease↗
PubMed1997

Octreotide: effective treatment for hyperparathyroidism? A prospective, randomized, controlled clinical trial.

BACKGROUND: Recent studies suggest a role for somatostatin in the medical treatment of hyperparathyroidism. In a prospective, randomized, controlled, triple blinded clinical trial in patients with primary or secondary hyperparathyroidism, we evaluated the response of biochemical parameters relevant in hyperparathyroidism to the somatostatin analog octreotide. METHODS: Forty patients each with primary or secondary hyperparathyroidism were studied. Among other parameters, serum calcium and serum phosphate, parathyroid hormone, calcitonin, osteocalcin, and octreotide were assessed before and repeatedly for 4 hours after a single intravenous application of 200 micrograms octreotide or placebo. Subsequent to operation, which was performed on all patients, somatostatin-receptor autoradiography of parathyroid tissue was performed. RESULTS: After administration of octreotide, which resulted in an increase of plasma levels to pharmacologic levels, no significant changes in any of the biochemical parameters investigated for were observed. Multivariate analysis did not identify patient subpopulations that responded to either drug or placebo (p > 0.05). Forty-five percent of patients receiving octreotide reported side effects: Parathyroid tissue samples of patients with primary or secondary hyperparathyroidism were negative for somatostatin-receptor expression. CONCLUSIONS: Octreotide has no discernible effect on biochemical parameters of patients with primary or secondary hyperparathyroidism. Absence of somatostatin receptors, together with lack of octreotide effects, suggests that somatostatin is not effective in the medical therapy of hyperparathyroidism.

Adolescent↗
PubMed1997

Isotransplantation of microencapsulated parathyroid tissue in rats.

Permanent hypoparathyroidism is one of the most difficult of all endocrine disorders to treat medically. While autotransplantation of parathyroid tissue is clinically established, allotransplantation without immunosuppression is still at the level of animal experiments. Although persons affected by hypoparathyroidism are facing a clearly reduced quality of life, hypoparathyroidism rarely is a life threatening condition. Therefore, systemic immunosuppression for recipients of allotransplants is not justified. A conceptional alternative would be protecting the tissue to be transplanted from the immunologic response by coating it with a semipermeable membrane (microencapsulation). In 1994, we succeeded in iso-, allo- and xenotransplantation of microencapsulated parathyroid tissue in an animal model. Unfortunately, prior to the first clinical use, further analysis of the coating substance (alginate) demonstrated that it has mitogenic properties. Here, we report on the first successful transplantation of microencapsulated parathyroid tissue using a purified, non-mitogenic alginate which is suitable for clinical use.

Animals↗
PubMed1997

Small bowel lengthening by mechanical distraction.

To evaluate whether the small bowel can be distracted by mechanical stress in analogy to limb lengthening by osteodistraction, a gut-lengthening apparatus was designed. This distractor was placed at the antimesenterical side of a defined jejunum segment in rabbits. Distraction was performed by 1 mm lengthening of the distractor once daily using extracorporal screws. An effective gut lengthening was achieved of 9.9 +/- 0.5 mm (approximately 100%) within 3 weeks. Treated animals gained weight and remained in good general condition. Fasting plasma levels of cholecystokinin, neurotensin, glucagon-like peptide-1, gastric inhibitory polypeptide, and insulin remained unaffected. Postoperative factor XIII levels were significantly diminished and gastrin was elevated during gut distraction. DNA and protein concentrations in the mucosa of the distracted gut segments corresponded to controls. Mucosal lactase and saccharase activities were reduced. In the distracted bowel segments total tunica muscularis thickness was more than doubled due to muscle cell hypertrophy. In distracted segments villous width was increased. Detection of proliferating mucosal crypt cells utilizing BrdUrd labeling revealed no effects. In conclusion, small gut lengthening by mechanical distraction is possible without major changes in gut morphology. This technique may hint a novel experimental approach for the treatment of short bowel syndrome.

Animals↗
PubMed1997

Prospective evaluation of ultrasonography in acute colonic diverticulitis.

BACKGROUND: The clinical diagnosis of acute colonic diverticulitis (ACD) can be difficult and ultrasonography by experts is valuable in establishing the diagnosis. This prospective observational trial aimed to assess the diagnostic accuracy and clinical value of ultrasonography performed routinely by surgical residents in training. METHODS: The clinical course of 187 unselected consecutive patients admitted with suspected ACD was studied prospectively. Patients who had surgery for generalized peritonitis were excluded, leaving 143 for evaluation. Ultrasonographic findings and clinical assessment on admission were correlated with the patient's clinicopathological data and discharge diagnosis respectively. RESULTS: Of 74 patients with proven ACD (prevalence 52 per cent) the diagnosis was made by ultrasonography in 62, with an accuracy of 88 per cent, sensitivity 84 per cent and specificity 93 per cent. Ultrasonography gave a false-negative result in 12 patients (negative predictive value (NPV) 84 per cent) and there were five false-positive findings (positive predictive value (PPV) 93 per cent). The final diagnosis in the latter five patients was colitis (two patients), caecal carcinoma (one), colonic ileus due to perforated sigmoid carcinoma (one) and suppurative pyosalpingitis with involvement of the sigmoid colon (one). The accuracy of clinical evaluation on admission was 71 per cent (sensitivity 82 per cent, specificity 55 per cent, PPV 72 per cent, NPV 68 per cent); however, in only 53 per cent of patients was the diagnosis considered clinically unequivocal. CONCLUSION: Ultrasonography is a useful and valid modality for imaging ACD and its differential diagnoses in the hands of sonographically trained surgeons. It is especially helpful when the clinical findings are equivocal.

Acute Disease↗
PubMed1997

The value of somatostatin-receptor scintigraphy in newly diagnosed endocrine gastroenteropancreatic tumors.

BACKGROUND: Conventional imaging techniques do not routinely detect endocrine gastroenteropancreatic tumors preoperatively. The purpose of this study was to determine whether the new technique of somatostatin-receptor scintigraphy would improve the detection rate of these tumors before initial treatment. STUDY DESIGN: In a prospective study, 55 patients with a recent diagnosis of endocrine gastroenteropancreatic tumors (22 intestinal carcinoids, 17 gastrinomas, 10 nonfunctioning pancreatic tumors, and 6 insulinomas), were examined with somatostatin-receptor scintigraphy, computed tomography, and ultrasonography. Results of the three imaging modalities were compared with findings at surgical exploration. RESULTS: None of the insulinomas were localized by somatostatin-receptor scintigraphy, but 4 of 6 insulinomas were detected by computed tomography and ultrasonography. Of 17 gastrinomas, 9 were detected by somatostatin-receptor scintigraphy; computed tomography and ultrasonography localized only 7. Metastases from the gastrinoma were localized by somatostatin-receptor scintigraphy in all cases; computed tomography and ultrasonography detected metastases in only 6 of 9 patients. Nonfunctioning tumors could be localized by somatostatin-receptor scintigraphy, computed tomography, and ultrasonography in 4, 7, and 8 of 10 cases, respectively. Detection rate for corresponding metastases was the same for all three imaging techniques. Primary carcinoids were identified by somatostatin-receptor scintigraphy, ultrasonography, and computed tomography in 7, 8, and 11 of 22 cases, respectively. Extra-abdominal metastases were detected by somatostatin-receptor scintigraphy in only 7 of 19 patients. CONCLUSIONS: In patients with insulinomas, somatostatin-receptor scintigraphy is not indicated because none of the six tumors was imaged. This holds true for nonfunctional pancreatic endocrine tumors and their metastases because no advantage for somatostatin-receptor scintigraphy was found over computed tomography and ultrasonography. In contrast, somatostatin-receptor scintigraphy is superior to computed tomography and ultrasonography for determining the extent of the disease in patients with gastrinomas or carcinoids. The problem of detecting primary tumors in these patients is not solved by somatostatin-receptor scintigraphy.

Adult↗
PubMed1997

[Value of preoperative blood coagulation analysis for assessment of hemorrhage risk in general surgery].

Coagulation studies, i.e. platelet count, prothrombin time (PT) and activated partial thrombin time (aPTT) are commonly employed preoperatively to identify patients at risk. In a retrospective study we evaluated the usefulness of these screening tests to predict postoperative bleeding in 1447 patients with abdominal and thoracic surgery. Forty-six patients (3.2%) experienced postsurgical bleeding. 12.2% of our patients had abnormal coagulation studies. The sensitivity of abnormal coagulation studies with respect to postoperative bleeding was 23.9%. The sensitivity of the parameter "patient at risk", i.e. patients with suspected coagulopathies due to drugs or disease of the liver or kidney, was 56.5%. Thirty-four out of 1008 patients without risk factors had abnormal coagulation tests but an uneventful postoperative course. Preoperative screening of PT and aPTT should be reserved for patients with known or suspected inherited or acquired coagulopathies.

Adult↗