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Biomedical subjects

R M Katon

Publications and source records attributed to R M Katon.

At least 73 records · Page 4Linked to original sources

Small bowel biopsy by coaxial catheter. A simple, rapid technique.

A new small intestinal biopsy technique was developed and evaluated: it involves the rapid replacement of a simple duodenal tube using a controllable spring guide and fluoroscopy. A suction biopsy catheter was then passed coaxially through the tube as often as needed for sampling, after which other diagnostic studies were done with the same intubation. In clinical trials totaling 31 biopsies in 15 adult patients, the method proved safe and effective. Currently, the time required to intubate the ligament of Treitz and obtain two biopsies is usually less than 15 minutes.

Adult↗

Pseudomembranous enterocolitis. Resurgence related to newer antibiotic therapy.

Six patients with pseudomembranous entercolitis were seen at one institution over a six-month period. Clindamycin therapy preceded the diagnosis in all six patients and possibly caused the disease in five cases. Common clinical features included diarrhea, abdominal pain, fever, leukocytosis, radiographic findings of large bowel dilatation with mucosal thickening and a characteristic sigmoidoscopic or gross pathologic demonstration of discrete yellow-white plaques on an otherwise normal mucosa. Complications included toxic megacolon and sigmoid colon perforation. Two of the six patients died. The literature since 1970 is tabulated to clarify the clinical and pathological features of pseudomembranous enterocolitis associated with newer antibiotic therapy. Lincomycin and clindamycin are strongly implicated in the recent resurgence of this formerly rare variety of colitis.

Adult↗

Treatment of malignant esophageal obstruction with silicone-coated metallic self-expanding stents.

Six patients with high-grade malignant esophageal obstruction were treated with silicone-coated metallic self-expanding esophageal stents (Z stents). Endoscopic placement of stents was well tolerated. All patients achieved excellent palliation, defined by a decrease of at least two dysphagia grades, which was sustained. Complications occurred during follow-up in four patients and included stent migration, silicone disruption with tumor ingrowth, food impaction, and perforation (discovered at autopsy) at the distal stent site. Three of the four complications were promptly treated by endoscopic or radiologic intervention. Recent modification in stent design and placement technique will hopefully reduce complications. The self-expanding stent has several theoretical advantages over the rigid plastic stent and Nd:YAG laser for palliation of obstructing esophageal malignancy.

Adenocarcinoma↗

Silicone-covered self-expanding metallic stents for the palliation of malignant esophageal obstruction and esophagorespiratory fistulas: experience in 32 patients and a review of the literature.

Esophagogastric malignancies often are manifested with progressive dysphagia or esophagorespiratory fistulas. Palliative modalities currently available have significant limitations. A modified Gianturco-Rösch silicone-covered self-expanding metallic Z stent was used in 32 consecutive patients with malignant esophageal obstruction (n = 24) or esophagorespiratory fistulas (n = 8). The stent was placed successfully in all patients. Dysphagia improved by at least two grades in 21 of the 24 patients (87.5%); the mean dysphagia grade fell from 3.21 to 1.08. Six of the 8 patients with fistulas were able to resume a normal diet, and the other 2 were able to eat solids without symptoms of aspiration. Complications occurred in 10/32 patients (31%) and included stent migration (4 patients), food impaction (2 patients), membrane disruption with tumor ingrowth (1 patient), tumor overgrowth (1 patient), early pressure necrosis with hemorrhage (1 patient), and late pressure necrosis with sepsis (1 patient). The latter 2 patients died, giving a mortality rate of 6.3%. Many complications were managed with endoscopic or interventional radiologic techniques. Although randomized prospective clinical trials are needed, the silicone-covered Gianturco-Rösch Z stent offers promise for the effective palliation of malignant esophageal obstruction and esophagorespiratory fistulas.

Adult↗

Tiny snares prove safe and effective for removal of diminutive colorectal polyps.

The efficacy of two new tiny snares has been evaluated for removal of diminutive (7 mm or less) colorectal polyps. The small size of the snares facilitates direct placement over a polyp, after which resection can be performed using monopolar current. Data were prospectively collected on 183 polyps, 2 to 7 mm in diameter, encountered in 90 patients. Polyp diameter, location relative to the splenic flexure, and histologic characteristics were noted, as were retrieval rate and complications. Ninety-four percent of the polyps could be removed with a tiny snare, and 88% of these were recovered. Forty percent of the polyps were located proximal to the splenic flexure, and 69% were neoplastic. The only complication was major hemorrhage in 1 patient (0.5%), in whom snare polypectomy without current application was used. Tiny snares can effectively and safely be used to remove diminutive colorectal polyps, and they may make "hot biopsy" forceps obsolete.

Adenoma↗

Treatment of malignant esophagorespiratory fistulas with silicone-covered metallic Z stents.

PURPOSE: To prospectively evaluate the clinical efficacy of covered metallic Z stents in the treatment of esophagorespiratory fistulas (ERFs). PATIENTS AND METHODS: Twelve patients with severe aspiration symptoms from malignant ERFs were treated with silicone-covered, metallic, self-expanding Gianturco-Rösch Z (GRZ) stents. RESULTS: Fluoroscopically guided stent placement was successful and well tolerated in all patients. Immediate postprocedural endoscopy and esophagography showed excellent coverage of the fistulas in all cases. Aspiration symptoms were completely relieved in eight of 12 patients (67%). Four of 12 patients (33%) were improved and able to eat a soft diet. There were no stent-related deaths. Nine patients have died and three patients are alive. Mean follow-up for the entire group was 3.9 months (range, 1 week to 10.5 months). Nonfatal complications occurred in three of 12 patients (25%). Complications included one membrane disruption and one granulomatous reaction with a slight upward stent migration. CONCLUSION: GRZ stents are an effective and safe means of palliation in patients with malignant esophagorespiratory fistulas.

Adult↗

Treatment of malignant esophageal obstructions with covered metallic Z stents: long-term results in 52 patients.

PURPOSE: To prospectively evaluate the clinical efficacy of silicone-covered Gianturco-Rösch self-expandable Z (GRZ) stents in the treatment of malignant esophageal obstruction. PATIENTS AND METHODS: GRZ stents were placed in 52 patients (39 men, 13 women) with severe dysphagia due to high-grade malignant esophageal obstruction. RESULTS: Stent placement was technically successful, and immediate relief of dysphagia was achieved in 50 of 52 patients (96%), with long-term relief in 47 patients (90%). Fifty-one patients (98%) died during follow-up (range, 1 week to 33 months; mean, 4.3 months). Late complications were most prevalent and included stent migration (n = 5), food impaction (n = 2), chest pain (n = 2), membrane disruption with tumor ingrowth (n = 1), granulomatous reaction above the stent (n = 1), esophageal perforation with mediastinitis (n = 1), and upper gastrointestinal hemorrhage (n = 4). Twelve complications were easily managed with medical, endoscopic, or radiologic intervention. Four deaths may have been related to stent placement (early mortality rate, 7.7%). CONCLUSION: GRZ stents provide relatively safe and effective long-term palliation in patients with severe, malignant esophageal obstruction.

Aged↗