PubMed Health⌕ Search

Biomedical subjects

R H Yuan

Publications and source records attributed to R H Yuan.

16 recordsLinked to original sources
PubMed2001

Effectiveness of transperitoneal and trans-retroperitoneal laparoscopic adrenalectomy versus open adrenalectomy.

PURPOSE: This study compared the effectiveness of laparoscopic adrenalectomy, using either a transperitoneal or trans-retroperitoneal approach, with that of open adrenalectomy in patients with benign adrenal tumors. METHODS: From February 1995 to April 2000, laparoscopic adrenalectomy was performed on 31 patients with adrenal tumors, including 16 aldosteronomas, 10 Cushing's adenomas, three nonfunctioning tumors, and two pheochromocytomas. A lateral trans-retroperitoneal approach was used for the first 16 patients and a lateral transperitoneal approach was used for the last 15 patients. Twenty-one patients who received open adrenalectomy during the same period served as a control group. Comparisons were made between laparoscopy and open groups, and between transperitoneal and trans-retroperitoneal groups. RESULTS: Conversion to open adrenalectomy was necessary in two cases--both in the trans-retroperitoneal group during the first 2 years of the study period. No other intraoperative complications occurred and blood transfusion was not used. Compared with the open group, the laparoscopic group had less blood loss (71 vs 124 mL), resumed oral feeding earlier (28 vs 60 hr), required less postoperative narcotics (45 vs 120 mg meperidine), and had shorter postoperative hospital stays (4.9 vs 7.6 days) (all p < 0.05). The mean operative time was longer in the laparoscopic group (203 vs 123 min, p < 0.001). There were no significant differences between the transperitoneal and trans-retroperitoneal laparoscopy groups in any of the studied parameters, except that the operative time was longer in the trans-retroperitoneal laparoscopy group (244 vs 166 minutes, p < 0.01). CONCLUSIONS: Decreased blood loss, less postoperative pain, earlier resumption of oral feeding, and shorter hospital stays were achieved in patients undergoing laparoscopic adrenalectomy. These findings indicate that laparoscopic adrenalectomy is the treatment of choice for benign adrenal tumors. The transperitoneal approach yielded shorter operative time than the trans-retroperitoneal approach, because it offered a clearer view and familiar landmarks.

Adrenalectomy↗
PubMed2000

Color Doppler vascularity index can predict distant metastasis and survival in colon cancer patients.

The purpose of this study was to investigate the clinical usefulness of the color Doppler vascularity index (CDVI) in patients with colon cancer before surgery. Forty-four patients with sonographically visible tumor mass of colon cancer were investigated. The CDVI of each tumor was determined using transabdominal color Doppler ultrasound. The CDVI was defined as the ratio of the number of the colored pixels within a tumor section to the number of total pixels in that specific tumor section and was calculated by using Encomate software (Electronic Business Machine Co. Ltd., Taipei, Taiwan). The correlation between the CDVI and clinicopathological factors, mode of recurrence, and patient survival was studied. For comparison, microvessel density (the mean number of microvessels in three areas of highest vascular density at x200 magnification) of the tumors of these 44 patients was also evaluated by using immunohistochemical staining of surgical specimens with anti-CD34. The microvessel density was not correlated with Dukes' classification, clinicopathological factors, and survival. The CDVI was significantly higher in the patients with lymph node metastases and vascular invasion than in those without such metastases and invasion (P = 0.006 and P = 0.0098, respectively). Moreover, in patients with a high CDVI (> 15%) and positive vascular invasion, survival was significantly poorer than in those with low CDVI (< or = 15%) and negative invasion (P = 0.0037 and 0.0039, respectively). Multivariate analysis indicated that liver metastasis, vascular invasion, and CDVI are independent prognostic factors in the patients with colon cancer. According to the mode of recurrence in 36 patients who underwent curative resection, the frequency of the distant organ recurrence was significantly higher in the high CDVI group (40%) than in the low CDVI group (0%). The CDVI is a good preoperative indicator of recurrence and patient survival in colon cancer. Thus, the CDVI may be helpful in stratifying patients for adjuvant therapy.

Adult↗
PubMed1999

Combined use of mini-laparoscope and conventional laparoscope in laparoscopic cholecystectomy: preservation of minimal invasiveness.

Mini-laparoscopic cholecystectomy using a 2-mm mini-laparoscope has been reported to be beneficial but technically difficult. This study attempted to evaluate the relative efficacy of a new method, which provides the benefits of both conventional and mini-laparoscopic cholecystectomy. From March 1997 to December 1997, 143 patients (49 men, 94 women, mean age 52.6 years, range 20-79), American Society of Anesthesiology (ASA) class I-II, underwent elective cholecystectomy by a combination of a 2-mm mini-laparoscope and 10-mm conventional laparoscope (combined lap-aroscopic cholecystectomy, C group) in National Taiwan University Hospital, Taipei, Taiwan. The entire procedure was done through four ports (one 11-mm port and three 2-mm ports). For comparison, records from 46 patients receiving mini-laparoscopic cholecystectomy (M group, 17 men, 29 women, mean age 49.0 years, range 26-76) and 139 patients receiving conventional laparoscopic cholecystectomy (L group, 47 men, 92 women, mean age 51.2 years, range 28-82) by the same operative team were included retrospectively. Mean operation time, time until first postoperative oral intake, dosage of analgesic, and postoperative hospital stay as well as possible complications were compared. No significant differences concerning the age, sex, and ASA classification were identified between all groups. The operative time of the C group (59.9 +/- 17.3 min, p = 0.420) but was significantly shorter than that of the M group (72.8 +/- 26.5 min, p < 0.001). No differences concerning the analgesic usage (0.5 +/- 0.8 unit vs. 0.4 +/- 0.7 unit, p = 0.372), postoperative oral intake (4.4 +/- 1.9 h vs. 3.3 +/- 2.3 h, p = 0.067), and postoperative hospital stay (1.7 +/- 0.7 days vs. 1.7 +/- 0.7 days, p = 0.941) were found between the C group and the M group. However, compared with the L group, analgesic usage (0.5 +/- 0.8 unit vs. 0.8 +/- 1.0 unit, p = 0.003) and time until first postoperative oral intake (4.4 +/- 1.9 h vs. 6.2 +/- 3.0 h, p < 0.001) were less, and the postoperative hospital stay (1.7 +/- 0.7 days vs. 2.0 +/- 0.9 days, p = 0.002) was significantly shorter in the C group. Combined use of the mini-laparoscope and the conventional laparoscope in cholecystectomy provides the benefits of both conventional laparoscopic and mini-laparoscopic cholecystectomy. It is easier to perform than cholecystectomy that uses the mini-laparoscope alone and results in a much smaller wound with less pain than conventional laparoscopic cholecystectomy. It is a feasible, safe procedure, and the minimal invasiveness of mini-laparoscopic cholecystectomy is preserved. It is an alternative way to deal with gallstone disease, especially for younger women, who tend to be more concerned about cosmetic outcome.

Adult↗
PubMed1998

Laparoscopic management of a gastric perforation after snare removal of a gastric leiomyoma.

A 67-year-old man with a history of myocardial infarction, who had been suffering intermittent epigastric pain and tarry stool for nine months, was referred to our hospital with a suspected gastric tumor. The panendoscopy showed a round, hard submucosal tumor at the greater curvature of the upper gastric body, near the fundus. An ulcer scar was observed on the surface of the tumor. Polypectomy using snare cauterization was carried out. However, severe abdominal pain and abdominal distension developed. A chest radiograph revealed bilateral subphrenic free air. Due to the high risk in this patient, laparoscopic repair of the gastric perforation was carried out using an Endo-GIA instrument. The postoperative course was uneventful. Feeding started on the third postoperative day, and the patient was discharged on the eighth day. A follow-up panendoscopy two months later showed a well-healed scar.

Aged↗
PubMed1998

Minilaparoscopic splenectomy: a new minimally invasive approach.

This report introduces our new technique in laparoscopic splenectomy. A 2-mm minilaparoscope and a conventional 10-mm laparoscope were used alternatively during the procedure, with a result of nearly no visible scar after the operation. Two young females diagnosed with idiopathic thrombocytopenic purpura, refractory to medical treatment, underwent laparoscopic splenectomy in our hospital. The whole procedure was finished through one 12-mm port (supraumbilical) and three 2-mm ports (subxiphoid, left midclavicular, and left midaxillary). The short gastric vessels and splenic vessels were clipped and divided by Endo-GIA II (U.S. Surgical Corp., Norwalk, CT) that was applied through the 12-mm port. The spleen was placed in a bag and was fractured to be removed piece by piece. A drain tube was not necessary after meticulous hemostasis. Two weeks after the operation, only three tiny wounds, resembling mosquito bites, were present at the left subcostal region. In conclusion, minilaparoscopic splenectomy is feasible and safe for patients with idiopathic thrombocytopenic purpura, and may ultimately be an alternative choice for patients desiring superior cosmesis.

Adult↗
PubMed1998

Laparoscopic subtotal gastrectomy with lymphadenectomy in a patient with early gastric cancer.

Laparoscopic surgery is rapidly gaining in popularity among general surgeons. It is not widely used to treat abdominal malignancies because of technical difficulties and the fear of peritoneal dissemination. We describe the use of laparoscopic surgery to treat early gastric cancer. A 66-year-old man was diagnosed with early gastric adenocarcinoma by endoscopic ultrasonography and biopsy. Subtotal gastrectomy along with removal of the perigastric (D1) and selective extraperigastric lymph nodes over the celiac trunk was accomplished laparoscopically, through five punctures and a minilaparotomy. The patient's convalescence was uneventful. Bowel sounds were heard on postoperative day 1. On postoperative day 3, he passed flatus. The patient was started on a clear liquid diet on postoperative day 5. There was neither leakage nor obstruction after oral intake. He was discharged on postoperative day 11. No local recurrence or distant metastasis was found during 16 months' follow-up. This is the first report of successful laparoscopic resection of early gastric cancer with lymph node dissection in Taiwan.

Aged↗
PubMed1998

Advantages of laparoscopic splenectomy for splenomegaly due to hematologic diseases.

Recent advancements in laparoscopic surgery have made laparoscopic splenectomy possible. We retrospectively compared the outcomes of laparoscopic versus open splenectomy in patients with idiopathic thrombocytopenic purpura (ITP) or beta-thalassemia. From July 1993 to July 1997, 52 patients (ITP, 43 cases; beta-thalassemia, 9 cases) underwent either laparoscopic (30 patients, 9 men, 21 women; average age, 36.9 years) or conventional open splenectomy (22 patients, 5 men, 17 women; average age, 34.3 years). The two groups were similar in terms of sex, age, diagnosis, duration of disease, preoperative platelet count, and spleen size. The mean surgical time, estimated amount of blood loss, duration of postoperative recovery, analgesic usage, and complications were compared between the two groups. Laparoscopic splenectomy was successful in 29 (97%) of the 30 patients. The mean surgical time in the laparoscopy group was longer than in the open splenectomy group (190.6 vs 113.9 minutes, p < 0.01). The laparoscopy group had earlier postoperative oral intake (15.2 vs 52.6 hours, p < 0.01), less usage of analgesics (meperidine 50 mg/unit, 1.1 vs 2.8 units, p < 0.01) and a shorter postoperative hospital stay (4.1 vs 6.8 days, p < 0.01). The estimated blood loss, incidence of accessory spleen, surgical complication rate, and recurrence rate of thrombocytopenia were similar in the two groups. Our findings show that laparoscopic splenectomy in patients with ITP or beta-thalassemia is as safe as the open approach. While laparoscopy required a longer surgical time, the recovery period was shorter, analgesic use was less, and physical discomfort was less severe.

Adolescent↗
PubMed1997

Seroprevalence of Helicobacter pylori in patients with surgical peptic ulcer.

BACKGROUND: Helicobacter pylori is known as a major cofactor in ulcerogenesis. However, the role of H pylori in surgical patients with peptic ulcer and its possible influence on surgical treatment is unclear. OBJECTIVES: To determine the prevalence of H pylori infection in surgical patients with complicated peptic ulcer diseases and analyze its clinical significance. DESIGN: A prospective, controlled study. SETTING: University-affiliated hospital and tertiary care center. SUBJECTS: Two study groups: surgical group (n = 66), i.e., patients who received surgical treatment for their peptic ulcer disease), and control group (n = 377) comprising 3 subgroups: normal volunteers (NV subgroup, n = 136) and patients who required only medical treatment for duodenal ulcer (DU subgroup, n = 119) or gastric ulcer (GU subgroup, n = 122) from January 1, 1994 to June 30, 1995. METHODS: Preoperative or overnight fasting serum samples were collected, and H pylori state was assessed by serum anti-H pylori IgG. RESULTS: Seropositivity was similar between the surgical group (60.6%) and NV control subgroup (58.8%), but it was highest in the DU control subgroup (87.4%) (P < .001 compared with NV control subgroup), followed by GU control subgroup (76.2%) (P < .01 compared NV). The patients with surgical peptic ulcer who had both seropositive and seronegative results for H pylori were similar for sex, age, social status, ulcer history, associated major medical problems, use of nonsteroid anti-inflammatory drugs, ulcer location, type of surgery, and ulceration recurrence rate. Although patients who underwent elective surgery had a higher seroprevalence rate (88.9%) than those requiring emergency surgery (56.4%) and patients who were seronegative for H pylori seemed to be associated with a higher major morbidity, these results were not statistically significant. CONCLUSION: No significant association of H pylori infection and peptic ulcer was noted between patients who required surgical treatment compared with those who required only medical treatment; H pylori played only a limited role in the cause of disease in surgical patients, perhaps only in the cases complicated with stenosis or intractable ulcers. This suggests that presently adequate acid reduction procedure will still be the main objective of surgical treatment and prevention of the ulcer recurrence.

Adult↗
PubMed1997

Mini-laparoscopic cholecystectomy: a cosmetically better, almost scarless procedure.

Laparoscopic cholecystectomy is the most common laparoscopic operation in the world and is accepted as the standard procedure for cholecystectomy. Although use of miniendoscope in diagnosis of gynecological disease has been performed for decades, using a 2-mm mini-laparoscope for cholecystectomy is new. From November 1996 to January 1997, 14 patients (6 men, 8 women; mean age 47 years) with gallbladder stone disease were treated by mini-laparoscopic cholecystectomy at National Taiwan University Hospital, Taipei, Taiwan. The entire procedure was done through four ports (an 11-mm subumbilical working port, a 2-mm subxiphoid video port, one 2-mm mid-clavicular retraction port, and one anterior axillary retraction port). The operative time for these patients ranged from 30 to 150 min, with an average time of 79.29 min. Suturing was not necessary for the three 2-mm wounds. The estimated blood loss was minimal, and no intraoperative transfusions were required. All patients were able to tolerate feeding within 8 h. The average postoperative hospital stay was 1.57 days. Neither complications nor operation-related mortality were seen. In conclusion, mini-laparoscopic cholecystectomy is a feasible and safe procedure with nearly scarless wounds with a much better cosmetic effect, especially for young female patients.

Antibiotic Prophylaxis↗
PubMed1996

Laparoscopic splenectomy: preliminary experience.

The role of conventional open splenectomy in the treatment of idiopathic thrombocytopenic purpura (ITP) is well known. As improvement in laparoscopic instruments and techniques have been made, laparoscopic surgery has been significantly extended to include more general surgical procedures. From July 1993 to March 1995, five patients with refractory ITP were treated by laparoscopic splenectomy at National Taiwan University Hospital. The entire procedure was completed under laparoscopic guidance in which four ports were used in four of the five cases. The operative time for these four patients ranged from 180 to 330 minutes with an average time of 225 minutes. The estimated blood loss ranged from 100 to 400 mL with an average of 175 mL. No intraoperative blood transfusions were required. A Penrose drain was in place for 2 to 3 days. All of the patients were able to tolerate a regular diet within 1 postoperative day. The average postoperative hospital stay was 5.25 days. No complications occurred. The remaining laparoscopic surgery was unsuccessful, requiring conversion due to severe bleeding. In conclusion, laparoscopic splenectomy is a feasible and safe procedure for patients with ITP. It may be an alternative choice for a variety of hematologic and pathologic conditions involving the spleen.

Adolescent↗
PubMed1991

Benign chest wall lipoblastoma: report of a case.

This report deals with a 22-month-old boy who had a benign lipoblastoma on the chest wall. The tumor was located intrathoracically and was well-encapsulated. It was yellowish in color with a shiny cut surface and consisted of multiple lobules. Histologically, peripheral immature lipoblasts with fat vacuoles of various size and central mature fat cells containing a single, large fat vacuole are characteristic of this tumor. No local recurrence has been found during the 17 months since total excision.

Adult↗
PubMed1988

Localization of protease nexin-1 on the fibroblast extracellular matrix.

Protease nexin-1 (PN-1) is a protease inhibitor that is secreted by fibroblasts and several other cultured cells. PN-1 forms complexes with certain serine proteases in the extracellular environment including thrombin, urokinase, and plasmin. The complexes then bind to the cells and are rapidly internalized and degraded. This report demonstrates that PN-1 is present on the surface of fibroblasts, bound to the extracellular matrix. Immunofluorescent studies showed that PN-1 colocalized with fibronectin on both intact cells and in preparations of extracellular matrix made from these cells. In contrast, PN-1 did not colocalize with the epidermal growth factor receptor, a plasma membrane marker. An enzyme-lined immunosorbent assay was developed which showed that the extracellular matrix contained at least 60-80% of the cellular immunoreactive PN-1. Extraction of the matrix with 2 M NaCl removed PN-1 in a form which reacted with 125I-thrombin to form complexes which were immunoprecipitated by anti-PN-1 IgG and were of identical size as complexes made from soluble PN-1 and 125I-thrombin. These data indicate that in addition to its role as a soluble protease inhibitor, PN-1 is also a component of the extracellular matrix and might control its proteolysis.

Amyloid beta-Protein Precursor↗
PubMed1977

Giant intracranial aneurysms: a review of 13 cases.

Thirteen cases of subarachnoid, extracavernous giant aneurysms are reported. The various types of presentation and treatment are discussed. Of interest is the fact that the paraclinoid carotid artery is the most common location for giant aneurysms. Thirty-one percent have another vascular abnormality associated with them, and 70% presented initially with a subarachnoid hemorrhage.

Adult↗
PubMedDate not supplied

Laparoscopic wedge resection of benign gastric tumor.

BACKGROUND/AIMS: In the past 2 years, 9 patients diagnosed as benign gastric tumor pre-operatively underwent laparoscopic wedge resection of stomach at National Taiwan University Hospital. Among them, 6 were females and 3 were males. METHODOLOGY: Histopathologically, 7 of 9 cases were of gastrointestinal stromal tumor (GIST). The clinical characteristics of this group were retrospectively reviewed and compared with another 12 cases of benign gastric tumor receiving open wedge resection in the same period. RESULTS: There were no differences in sex, age, and pre-operative diagnosis in these two groups. It took a significantly longer operation time in the laparoscopic group than it did in the open group (205.71 vs. 97.5 min, p<0.05). However, the patients of the laparoscopic group started post-operative oral intake earlier (4.0 vs. 5.58 days, p<0.05), had shorter hospital stays (6.67 vs. 10.77 days, p<0.05), and lower analgesic usage rate (55% vs. 100%). There were no differences in operative complication rates. CONCLUSIONS: Laparoscopic resection of benign-gastric tumor is recommended as a minimally invasive procedure.

Adult↗