Biomedical subjects
Publications and source records attributed to H J Bonjer.
The value of laparoscopic surgery for colorectal malignancy as compared with open surgery will be determined in the COLOR-trial. The disease-free survival time is the primary end point. Twenty-one hospitals in the Netherlands and Scandinavia will participate in the trial. In the COLOR trial 1500 patients with colon carcinoma will be randomised for either a laparoscopic or open colon resection.
OBJECTIVE: Evaluation of endoscopic retroperitoneal adrenalectomy in patients with adrenal tumours less than 6 cm in diameter. DESIGN: Retrospective analysis. SETTING: University Hospital Rotterdam-Dijkzigt, Department of General Surgery, Rotterdam, the Netherlands. METHOD: Analysis of per- and postoperative data on 19 patients subjected to endoscopic retroperitoneal adrenalectomy; 3 patients had bilateral surgery. RESULTS: Twenty adrenal tumours in 17 patients were successfully removed endoscopically. Conversion to lumbotomy was necessary in the two other cases. Median operative time was 85 min (range: 50-120). Median blood loss was 50 ml (10-400). Median postoperative hospital stay was 4 days (2-14). CONCLUSION: Endoscopic retroperitoneal adrenalectomy is associated with minimal morbidity and therefore valuable in patients with adrenal tumours smaller than 6 cm in diameter.
The success of parathyroid surgery is determined by the identification and removal of all hyperactive parathyroid tissue. Ectopic location of parathyroid tumours and fibrosis due to previous operations can cause failure of parathyroidectomy. Parathyroid tumours accumulate and retain 2-methoxyisobutylisonitrile (MIBI) labelled with technetium-99m. This study assesses the value of intra-operative localization of parathyroid tumours using a hand-held gamma detector in patients with hyperparathyroidism and parathyroid cancer. Twenty patients undergoing their first operations for hyperparathyroidism, 15 patients undergoing reoperations for either persistent or recurrent hyperparathyroidism and two patients with parathyroid cancer were studied. Radioactivity in the neck and the mediastinum was recorded by a gamma detector after administration of 370 MBq 99m Tc-MIBI. Surgical findings and postoperative serum levels of calcium were documented. The sensitivity of the gamma detector in identifying parathyroid tumours was 90.5% in first parathyroidectomies, 88.9% in reoperations for either persistent or recurrent hyperparathyroidism and 100% in parathyroid cancer. One false-positive result was due to a thyroid nodule. Hypercalcaemia ceased in all but one patient postoperatively. It is concluded that employment of the gamma detector is to be advocated in first parathyroidectomies when a parathyroid tumour cannot be discovered, in reoperations for either persistent or recurrent hyperparathyroidism and in surgery for parathyroid cancer.
PURPOSE: The aim of this study was to evaluate the role of defecography in predicting clinical outcome of rectocele repair. METHODS: Between January 1988 and July 1994, 74 consecutive patients (median age, 54 (range, 35-81) years) with a rectocele and symptoms of obstructed defecation were studied prospectively. After preoperative evaluation by a standardized questionnaire, physical examination, and defecography, a combined transvaginal/transanal rectocele repair was performed. At follow-up, all patients had defecography. Long-term results were qualified by an independent observer after a median follow-up of 58 (range, 14-89) months as "excellent," "good," or "poor." RESULTS: Rectocele repair was considered excellent in 37 patients and good in 13 patients. Defecography six months after surgery did not show persistent or recurrent rectocele in any of the patients. Size of the rectocele, barium-trapping in the rectocele, internal intussusception, rectal evacuation, and perineal descent did not appear to influence clinical outcome. Radiologic evidence of anismus did not correlate with long-term results of rectocele repair. CONCLUSIONS: Combined transanal/transvaginal repair of rectocele is an efficient therapy in patients with obstructed defecation. Various defecographic parameters (size of rectocele, internal intussusception, rectal evacuation, perineal descent, radiologic signs of anismus) do not appear to influence clinical outcome of surgery. The main value of defecography is the objective demonstration of rectocele and any associated abnormalities such as an enterocele preoperatively and again in objective assessment of the postoperative results.
BACKGROUND: A randomized clinical trial was performed to compare open appendectomy (OA) and laparoscopic appendectomy (LA). METHODS: 201 patients with similar characteristics of appendicitis were randomized to either OA or LA. Operative time and technique, reintroduction of diet, postoperative pain, use of analgesia, hospital stay, and complications were documented. RESULTS: 104 patients were allocated to the OA group and 97 to the LA group. Postoperative pain was significantly less in the LA group on the 1st (p < 0.001) and 2nd (p < 0.001) postoperative day, resulting in less use of analgesics on both days (p < 0.001). Restoration of diet was similar in both groups. Mean operative time was longer in the LA group: 61 vs 41 min (p < 0.001). Postoperative complications did not differ in either group, except for wound infections (six OA group vs zero LA group, p < 0.05). Mean hospital stay was similar in both groups. CONCLUSIONS: LA results in less postoperative pain and fewer wound infections. The laparoscopic procedure is technically more demanding to perform, resulting in longer operative time.
BACKGROUND: In experimental studies on the effects of laparoscopic procedures on tumor biology, a localized tumor model is desirable. The spleen and the kidney are preferable, because these organs are amenable to tumor placement and subsequent removal. This study describes the technique of laparoscopic splenectomy and nephrectomy in the rat model. METHODS: Pneumoperitoneum was established by CO2 insufflation. Laparoscopic splenectomy involved two-handed dissection, intracorporeal ligation, and division of gastrosplenic attachments and hilar and short gastric vessels. Laparoscopic nephrectomy was done by intracorporeal ligation and division of the renal vessels and the ureter after mobilization of the kidney. RESULTS: Laparoscopic splenectomy was performed in six rats; laparoscopic nephrectomy was done in six rats. Operative time ranged from 45 to 90 min for splenectomy and from 40 to 65 min for nephrectomy. Postoperatively, two rats died from hemorrhage. Necropsy of the rats after 10 days revealed adhesion in three rats after splenectomy and in four rats after nephrectomy. Inflammatory processes were found around the silk ligatures in all rats after splenectomy; in two rats wound infections occurred at the port sites. CONCLUSIONS: Laparoscopic splenectomy and nephrectomy in the rat proved technically feasible and may provide new localized tumor models suitable to be used in further studies on the oncological effects of laparoscopic surgery.
Explore the source record for details and available documents.
OBJECTIVE: Assessment of 99mTechnetium-sestamibi scintigraphy and ultrasonography as methods of locating enlarged parathyroid glands before operation. DESIGN: Retrospective analysis. SETTING: University hospital, The Netherlands. SUBJECTS: 21 patients with primary hyperparathyroidism and 6 patients with persistent or recurrent hyperparathyroidism. INTERVENTIONS: Single radionuclide scintigraphy with 99mTc-sestamibi, ultrasonography of the neck, and parathyroidectomy. MAIN OUTCOME MEASURES: Operative findings, postoperative serum calcium concentrations. RESULTS: 99mTc-sestamibi scintigraphy correctly identified 17 of 21 parathyroid tumours in patients who were about to undergo their first parathyroidectomy (sensitivity = 81%) with a positive predictive value of 94% and all 6 in patients with persistent or recurrent hyperparathyroidism. Ultrasonography correctly identified 13 parathyroid tumours in 18 patients about to undergo their first parathyroidectomy (sensitivity = 72%) with a positive predictive value of 93%, but only 3 among the 6 patients with persistent or recurrent hyperparathyroidism. CONCLUSION: Single radionuclide scintigraphy with 99mTc-sestamibi seems to identify the sites of parathyroid tumours accurately in patients with persistent or recurrent hyperparathyroidism but is not recommended for patients with primary hyperparathyroidism. Combining scintigraphy with ultrasonography does not improve the accuracy.
BACKGROUND: The role of laparoscopic surgery for malignant disease is controversial. To evaluate differences in tumour growth after conventional and laparoscopic surgery, an experimental study was performed in rats. METHODS: After intraperitoneal injection of CC-531 colonic cancer cells or subcapsular renal implantation of CC-531 cancer cells, rats underwent either laparoscopically assisted small bowel resection, open small bowel resection or anaesthesia only. Peritoneal tumour growth and subcapsular renal tumour growth were assessed after operation. RESULTS: Peritoneal tumour growth was the least after anaesthesia only (P < 0.05) and less after laparoscopic than open resection (P < 0.05). Subcapsular renal tumour growth after either laparoscopic resection or anaesthesia only was less than after open resection (P < 0.01). CONCLUSION: Laparoscopic surgery was associated with less tumour growth than conventional surgery in this experimental study.
BACKGROUND: Closed laparoscopy, employing a Veress needle and blind insertion of the first trocar, is favoured by most laparoscopic surgeons. The potential danger of this technique is the occurrence of visceral or vascular injury. Establishment of pneumoperitoneum by an open technique using a blunt-tipped trocar may be a safer alternative. METHODS AND RESULTS: Retrospective review of the literature and the authors' experience was used to compare closed and open laparoscopy. Data on closed laparoscopy in 489335 patients and on open laparoscopy in 12444 patients were culled. Rates of visceral and vascular injury were respectively 0.083 and 0.075 per cent after closed laparoscopy, and 0.048 per cent and zero after open laparoscopy. Mortality rates after closed and open laparoscopy were respectively 0.003 per cent and zero. Pearson chi 2 analysis demonstrated a statistically significant difference in terms of visceral and vascular injury between closed and open laparoscopy (P = 0.002); there was no such difference for mortality rates. CONCLUSION: Open establishment of pneumoperitoneum is advocated in laparoscopic surgery because it is safer than the closed method.
BACKGROUND: Conventional open adrenal surgery requires relatively large incisions and is associated with postoperative wound pain, intercostal neuralgia and pulmonary complications. Introduction of laparoscopic techniques has enabled development of minimally invasive adrenalectomy. METHODS: A case-control study of nine open, nine transperitoneal laparoscopic and 12 retroperitoneal endoscopic adrenalectomies was done in patients who were matched for Quetelet index, adrenal disorder and size of adrenal lesion; all tumours were less than 6 cm in diameter. RESULTS: Conversion to open adrenalectomy was necessary in two patients having transperitoneal laparoscopic adrenalectomy and in one having retroperitoneal endoscopic adrenalectomy. Operative time was longest in transperitoneal laparoscopic adrenalectomy (P = 0.004 and P = 0.005 versus open and retroperitoneal endoscopic adrenalectomy respectively). Blood loss was least in retroperitoneal endoscopic adrenalectomy (P = 0.01 versus both other groups). End-tidal carbon dioxide increase was greater in transperitoneal laparoscopic and retroperitoneal endoscopic than in open adrenalectomy (P = 0.014 and P = 0.01 respectively). After retroperitoneal endoscopic adrenalectomy, use of analgesia was least (P = 0.0003 versus other groups). Postoperative hospital stay was shortest after retroperitoneal endoscopic adrenalectomy (P = 0.024 and P = 0.027 versus open and transperitoneal laparoscopic procedures respectively). CONCLUSION: Retroperitoneal endoscopic adrenalectomy was optimal in patients with small adrenal tumours.
BACKGROUND: Thoracoscopic resection of the first through the fourth thoracic sympathetic ganglion for palmary and axillary hyperhidrosis and Raynaud's syndrome is associated with a high initial success rate. However, the reported incidence of compensatory hyperhidrosis of the trunk and legs and Horner's syndrome are high. This study assesses the results of thoracoscopic sympathectomy limited to transection of the interganglionic trunk or resection of one or two thoracic ganglia. METHODS: Twenty-eight thoracoscopic sympathectomies were done for dystrophy of the hand (n = 9), palmar and axillary hyperhidrosis (n = 6), and Raynaud's syndrome (n = 4). The extent of sympathectomy varied from interganglionic division between the second and third ganglion (n = 12), to resection of the third ganglion (n = 12), to resection of the second and third ganglion (n = 4). RESULTS: Sympathectomy resulted initially in relief of symptoms in all cases. Horner's syndrome did not occur. CONCLUSIONS: After a median follow-up of 11 months, two of nine patients with dystrophy judged the result of operation as good. All patients with hyperhidrosis and Raynaud's syndrome judged the result of sympathectomy as good. Compensatory hyperhidrosis was experienced by two patients with dystrophy of the hand who had removal of the second and third sympathetic ganglion.
BACKGROUND: The ability of laparoscopic techniques to treat malignant disease is controversial. We developed a rat model to assess metabolic and oncological effects of laparoscopic surgery. METHODS: Experiment I. The postoperative body weight in 10 rats having laparoscopic bowel resection (group I), 10 rats having open bowel resection (group II) and 5 rats having anesthesia only (group III) was determined. Experiment II. Tumor take was scored in 11 rats having laparoscopic bowel resection (group IV), 11 rats having open bowel resection (group V), 6 rats having CO2 pneumoperitoneum without bowel resection (group VI) and 6 rats having anesthesia only (group VII). All rats had CC531 cancer cells injected intraperitoneally postoperatively. RESULTS: Experiment I. Body weight loss in group I compared to group II (p<0.036). Rats of group III lost no weight postoperatively. Experiment II. Tumor take was less in the subcutis (p=0.005), parietal peritoneum (p<0.001) and bowel anastomosis (p=0.021) in group IV compared to group V. Tumor take was significantly greater at all sites except for subcutis in group VI compared to VII (all p<0.022). CONCLUSIONS: Laparoscopic surgery is associated with less postoperative weight loss and less tumor take compared to open surgery. CO2 insufflation appears to increase tumor take.
A 50-year-old woman is described with a very unusual combination of MEN-1 syndrome with a negative family history. At first she had been treated because of a clinically non-functioning pituitary adenoma in the maxillary sinus. Six years later a carcinoid tumour was discovered by means of 111In-pentreotide scintigraphy.
Explore the source record for details and available documents.
OBJECTIVE: A tumor model in the rat was used to study peritoneal tumor growth and abdominal wall metastases after carbon dioxide (CO2) pneumoperitoneum, gasless laparoscopy, and laparotomy. SUMMARY BACKGROUND DATA: The role of laparoscopic resection of cancer is under debate. Insufflation of the peritoneal cavity with CO2 is believed to be a causative factor in the development of abdominal wall metastases after laparoscopic resection of malignant tumors. METHODS: In the solid tumor model, a lump of 350-mg CC-531 tumor cells was placed intraperitoneally in rats having CO2 pneumoperitoneum (n = 8), gasless laparoscopy (n = 8), or conventional laparotomy (n = 8). After 20 minutes, the solid tumor was removed through a laparoscopic port or through the laparotomy. In the cell seeding model, 5 x 10(5) CC-531 cells were injected intraperitoneally before CO2 pneumoperitoneum (n = 12), gasless laparoscopy (n = 12), or laparotomy (n = 12). All operative procedures lasted 20 minutes. After 6 weeks, in the solid tumor model and after 4 weeks in the cell seeding model, tumor growth was scored semiquantitatively. All results were analyzed using the analysis of variance. RESULTS: In the solid tumor model, peritoneal tumor growth in the laparotomy group was greater than in the CO2 pneumoperitoneum group (p < 0.01). Peritoneal tumor growth in the CO2 group was greater than in the gasless group (p < 0.01). The size of abdominal wall metastases was greater at the port site of extraction of the tumor than at the other port sites (p < 0.001). In the cell seeding model, peritoneal tumor growth was greater after laparotomy in comparison to CO2 pneumoperitoneum (p < 0.02). Peritoneal tumor growth in the CO2 group was greater than in the gasless group (p < 0.01). The port site metastases in the CO2 group were greater than in the gasless group (p < 0.01). CONCLUSIONS: The following conclusions can be made: 1) that direct contact between solid tumor and the port site enhances local tumor growth, 2) that laparoscopy is associated with less intraperitoneal tumor growth than laparotomy, and 3) that insufflation of CO2 promotes tumor growth at the peritoneum and is associated with greater abdominal wall metastases than gasless laparoscopy.
We studied a 45-yr-old woman with food-dependent Cushing's syndrome. Plasma cortisol levels were subnormal (4-47 nmol/L) after an overnight fast and increased after a mixed meal to values between 500-1000 nmol/L. There was a close correlation between circulating gastric inhibitory polypeptide (GIP) and cortisol levels during normal food intake (r = 0.92; P < 0.0002). Plasma corticotropin (ACTH) levels were undetectable. Nonfasting plasma cortisol levels were not suppressed by low or high doses of dexamethasone. Plasma ACTH and cortisol levels did not increase after human CRH administration, but fasting plasma cortisol levels increased after ACTH treatment. The infusion of GIP increased plasma cortisol levels to 7.8 times above baseline. Radiological and cholesterol uptake studies pointed to a unilateral adrenal adenoma. Treatment with octreotide initially prevented the meal-induced increases in cortisol and GIP levels and decreased urinary cortisol excretion. Unilateral adrenalectomy was performed. Cortisol production by cultured adrenal adenoma cells from the patient was stimulated by GIP and ACTH. In situ hybridization studies using a GIP receptor probe showed an abundant expression of GIP receptor messenger ribonucleic acid in the adrenocortical adenoma. We conclude that food-dependent Cushing's syndrome results from the expression of GIP receptors on adrenocortical adenoma cells.