Biomedical subjects
Publications and source records attributed to S T Ko.
The typical concept of endoscopic surgery is the performance of surgical procedures in the two major body cavities, the abdomen and thorax. To perform this, small incisions for the ports are needed to introduce optics and instruments. Typically, the optic and the instruments are introduced from different angles. The access itself is associated with a reduced trauma.
This pilot study was conducted to determine if percutaneous endoscopic external ring (PEER) hernioplasty would be a viable alternative to the conventional and laparoscopic methods of tension-free repair. The procedure consists of (1) a 2.0-2.5-cm incision over the external inguinal ring to reach the emerging spermatic cord structures, and ligation and excision of the hernia sac and (2) insertion of an endoscope-attached retractor through the external ring, into the inguinal canal for visualization, dissection of posterior inguinal wall, and placement of mesh to complete tension-free repair. PEER hernioplasty was used to treat 48 patients with 60 primary hernias (bilateral in 12 patients) between January 1993 and December 1994. Median follow-up was 12 months and ranged from 5 to 22 months. All patients were discharged within 24 h after surgery except for one. All patients resumed their normal activity within 2-3 weeks. Only three complications were encountered (two scrotal hematomas and one inguinal seroma). To date, there has been recurrence of two hernias in one patient. We conclude that PEER hernioplasty is an effective method of repair of primary hernias that is less invasive than the conventional approach and both less invasive and more cost-effective than laparoscopic approaches.
UNLABELLED: Transanal endoscopic microsurgery (TEM) was first used on a regular basis in the United States in 1990. Because there is a sole source of instrumentation, the surgeons who use this equipment are known to us. Thus, this earliest registry is a compilation of data based on most patients who underwent TEM in the United States from 1990 to 1994. METHOD: One hundred fifty-three cases were voluntarily registered by six surgeons. Pathology included 54 carcinomas, 82 adenomas, and 17 other entities. Most resections were full thickness. Fifty percent of cases were out of reach of standard instruments. Complication rate, hospital stay, and blood loss were recorded. Technical difficulties at time of surgery (9 percent), early complications (15 percent), and late complications (5 percent) have been tabulated. RESULTS: Recurrence rates for carcinoma were 10 percent for T1, 40 percent for T2, and 66 percent for T3 stages. Failures were treated by abdominoperineal resection or low anterior resection. Adenomas recurred in 11 percent, but these recurrences were small and easily treatable. CONCLUSION: TEM has a low complication rate. By carefully selecting small, superficial cancers and adenomas, TEM results in superior outcome over other approaches to the mid and upper rectum.
UNLABELLED: Strict credentialing and proctoring guidelines were set up prior to initiating a program of laparoscopic cholecystectomy at the Good Samaritan Hospital in Downers Grove, Illinois. This is a private 386-bed community hospital. At the inception of the program, there were 15 general surgeons who were going to participate in this program. In 1992, there were 20 general surgeons performing the laparoscopic cholecystectomy (LC). The following guidelines were approved by the Credentials Committee and authorized by the Executive Committee: A. Training: A SAGES-approved or equivalent course in LC, meeting or exceeding SAGES guidelines. B. Proctoring: Proctoring of 10 LC cases, prior to operating independently. C. Prevention of injuries: Two surgeons credentialed in LC to operate as a surgeon-cosurgeon team. D. EVALUATION: 100% concurrent review of all LC cases.
Complications of laparoscopic cholecystectomy were evaluated by a survey of surgical department chairpersons at 4,292 US hospitals. The 77,604 cases were reported by 1,750 respondents. Laparotomy was required for treatment of a complication in 1.2% of patients. The mean rate of bile duct injury (exclusive of cystic duct) was 0.6% and was significantly lower at institutions that had performed more than 100 cases. Bile duct injuries were recognized postoperatively in half of the cases and most frequently required anastomotic repair. Intraoperative cholangiography was practiced selectively by 52% of the respondents and routinely by 31%. Bowel and vascular injuries, which occurred in 0.14% and 0.25% of cases, respectively, were the most lethal complications. Postoperative bile leak was recognized in 0.3% of patients, most commonly originating from the cystic duct. Eighteen of 33 postoperative deaths resulted from operative injury. These data demonstrate that laparoscopic cholecystectomy is associated with low rates of morbidity and mortality but a significant rate of bile duct injury.
Explore the source record for details and available documents.
Transanal endoscopic microsurgery (TEM) has emerged as a minimally invasive means of resecting rectal tumors. Developed in Germany and now being used with increasing frequency in the United States, TEM utilizes a 40-mm operating rectoscope, which is sealed with an airtight facepiece. Carbon dioxide is constantly infused, thereby distending the rectum and maintaining visibility. A variety of instruments, such as tissue graspers, a high-frequency knife, suction, and needle holders, are inserted through the facepiece. Adenomas that are small, large, or even circumferential, as well as selected carcinomas up to 24 cm, can be removed with TEM instrumentation. The optics provide sixfold magnification, and this, combined with the constantly distended operative field, allows for a precise excision of the tumor as well as closure of the wound. For lesions in the mid and upper rectum, TEM is an alternative to a transsacral or transabdominal approach, with subsequently shorter hospital stay and fewer complications.
With the advent of laparoscopic cholecystectomy, assessment of data and its relationship to quality of care became important. The Mount Sinai Hospital Medical Center conducted a prospective survey in conjunction with the Society of American Gastrointestinal Endoscopic Surgeons (SAGES) National Survey. In this survey, only two surgeons operated as surgeon and co-surgeon with an extremely small rate of complication. A national survey of chairpersons in surgery was designed at Rush Presbyterian St. Luke's Hospital, and 4300 chairpersons were mailed questionnaires to record complications of laparoscopic cholecystectomy. There were 36,232 patients and 3111 surgeons in the survey. The Southern Surgeons Club experience, as reported in New England Journal of Medicine, was reviewed. Because of the complexity of understanding the implications of the survey results, the authors have arrived at a simplified system of evaluating quality of care in laparoscopic cholecystectomy. In this system only three considerations are taken into account: (a) elective conversions to standard operation, (b) forced conversions (due to iatrogenic injuries), and (c) reoperation rate (delayed complication). It is hoped that data collection will be simplified and more meaningful.
A 72-year-old white male was found to have a 6-cm submucosal mass at 35 cm on screening sigmoidoscopy. The lesion had all the characteristics of a submucosal lipoma. Instead of performing a laparotomy with its potential morbidity, the lesion was removed laparoscopically in its entirety without untoward operative sequelae. Laparoscopic techniques have had a profound impact on the treatment of patients with surgical disorders. This new technology can be applied to selected patients with colorectal diseases.
The present paper reviews 300 laparoscopic cholecystectomies with intraoperative cholangiograms that were performed by the authors. The development and evolution of this procedure are described along with the results. The guidewire technique used for operative cholangiography and the maneuver applied to control bleeding of the cystic artery are detailed. Five cases were converted to open operations. No serious complications were encountered. One common bile duct injury occurred during endoscopic retrograde cholangiopancreaticography performed on postoperative day 8 for diagnostic purposes.
The influence of caffeine on secretion of catecholamines (CA) was examined in the isolated perfused rat adrenal gland. Caffeine (0.3 mM) perfused into an adrenal vein of the gland produced a marked increase in secretion of CA. This secretory effect of CA evoked by perfusion of caffeine for one minute was considerably prolonged, lasting for more than 90 minutes. The tachyphylaxis to releasing effect of CA induced by caffeine was observed by repeated perfusion of this drug. The caffeine-evoked CA secretion was markedly inhibited by pretreatment with ouabain, trifluoperazine, TMB-8 and perfusion with calcium-free Krebs solution containing 5 mM EGTA, but was not affected by perfusion of calcium-free Krebs solution without other addition. CA secretion evoked by caffeine was not reduced significantly by pretreatment with chlorisondamine but after the first collection of perfusate for 3 min was clearly inhibited. Interestingly, the caffeine-evoked CA secretion was considerably potentiated by pretreatment with atropine or pirenzepine, but after the first collection for 3 min it was markedly decreased. These experimental results suggest that caffeine causes a marked increase in secretion of CA from the isolated perfused rat adrenal gland by an extracellular calcium-independent exocytotic mechanism. The secretory effect of caffeine may be mainly due to mobilization of calcium from an intracellular calcium pool in the rat chromaffin cells and partly due to stimulation of both muscarinic and nicotinic receptors.
Mucus samples obtained from 61 patients with different types of colon and rectal disease were assayed for CK isoenzyme fractionation. Twelve additional patients without evidence of such diseases were used as reference subjects. The diseases surveyed were hemorrhoids, proctocolitis, polyps, and cancer of the colon and rectum. The CK BB fraction was predominant in the mucus of the reference subjects and in mild cases of hemorrhoids and polyps. With inflammation of degeneration of the colonic mucosa, the present CK BB decreased and the percent of CK MM increased. It is speculated that the increased CK MM possibly derives from increased permeability of degeneration of the colonic wall, permitting plasma CK MM to admix with the mucus. Mucin CK isoenzyme fractionation may be useful in assessing the pathogenesis of colonic and rectal diseases, as a marker to monitor the efficacy of the therapeutic regimen, and as a technique for monitoring conversion of a premalignant process into a malignant one.
Explore the source record for details and available documents.
Relationships between various types of chronic anemia, wound healing, and red cell 2,3-diphosphoglycerate (2,3 DPG) were examined in rabbits. Wound tensile strength and energy absorption were not affected by chronic iron-deficiency anemia, the chronic hemolytic anemia caused by intravenous water infusion nor by chronic hemolytic anemia caused by intravenous water infusion nor by chronic phenylhydrazine-induced anemia. Red cell 2,3 DPG levels were increased in the anemia of iron deficiency and were normal in the rabbits with chronic phenylhydrazine-induced anemia at the time of wound excision but were low following phynylhydrazine injection. The results show that chronic anemia per se does not affect the tensile strength and energy adsorption of wound healing. The findings suggest that the wound healing process may differ in certain types of anemia.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Pharbitis nil seedlings rapidly metabolized (-)-kaurene-17-(14)C administered to the cotyledons. Less than 20% of the radioactivity was recovered by extraction of the cotyledons on the following day. Of this the major metabolite was an unidentified acidic material which did not correspond chromatographically to any of the known gibberellins.Significant differences were observed between the radioactivity found in the buds of a group of seedlings subjected to photoperiodic floral induction and that in a noninduced group. In both cases almost all of this radioactivity was in the neutral fraction, but thin-layer chromatography of these fractions revealed that the induced group contained 2 or more labelled components which were either absent or present in lower concentrations in the noninduced group.
With the introduction of the technique of Interventional laparoscopy, a new era of minimally invasive general surgery has begun. The well-established principles of general surgical technique have not been altered by this new technology. As the new laparoscopic technology has become available, intraabdominal laparoscopic suturing and ligating techniques have been developed. The authors have attempted to elucidate the techniques of endoligation, "Endoloop" application, endosuture placement, sling suture placement, and continuous suture placement in laparoscopic surgery.