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H J Bonjer

Publications and source records attributed to H J Bonjer.

At least 55 records · Page 3Linked to original sources
PubMed2001

Impact of randomized trials on the application of endoscopic techniques for inguinal hernia repair in The Netherlands.

BACKGROUND: One year after publication of a Dutch prospective trial randomizing patients with inguinal hernias to either endoscopic or open repair, a questionnaire was sent to all Dutch surgeons to evaluate the impact of this trial on the application of endoscopic inguinal hernia repair in the Netherlands. METHODS: All 780 registered Dutch surgeons were surveyed. The performance of endoscopic inguinal hernia repair, the technique and the indications, the involvement of surgical residents, the motives for use of conventional techniques, and the type of open repair were documented. RESULTS: The response rate was 100%. Endoscopic inguinal hernia repair was performed by 16% of Dutch surgeons. For 81% of the surgeons, the total extraperitoneal approach was the preferred endoscopic technique. Primary inguinal hernias were approached endoscopically by only 54% of these surgeons, and recurrent hernias by 92%. The technique of choice for open repair of primary hernias was the Shouldice repair. The predominant repair for recurrent inguinal hernias was the Lichtenstein technique. CONCLUSIONS: Although randomized clinical trials have provided evidence that the endoscopic approach to inguinal hernias is preferable, only 1 of 6 Dutch surgeons has adopted endoscopic inguinal hernia repair. Improvement in training of both surgical residents and surgeons and increasing awareness among medical doctors and patients about the benefits of endoscopic inguinal hernia repair are necessary to enhance the acceptance of this valuable technique for inguinal hernia repair.

Evidence-Based Medicine↗
PubMed2001

Fine needle aspiration cytology of thyroid nodules: how accurate is it and what are the causes of discrepant cases?

Fine-needle aspiration cytology (FNAC) is widely accepted as the most accurate, sensitive, specific and cost-effective diagnostic procedure in the assessment of thyroid nodules and helps to select people preoperatively for surgery. The purpose of this study was to evaluate the results of thyroid FNAC in our institution and to determine the reasons for discrepancies between the cytological and histological diagnosis. We evaluated the cytological and histological results of 254 FNACs obtained from 231 patients who underwent subsequent thyroid surgery. All of the material was blindly reviewed for quality control, by one experienced cytopathologist. All FNACs were carried out under ultrasound guidance. The cytological diagnosis was classified as benign, suspicious, malignant or unsatisfactory. The definitive histological study showed benign lesions in 195 of the 231 patients (84%). A benign diagnosis based on FNAC was correct in 105 of the 108 benign cases (97%). FNACs diagnosed as 'suspicious' resulted in a distribution of 49 benign (79%) and 13 malignant (21%) diagnoses. FNAC showed malignancy in 34 cases (13%) and in only one case did the final histology differ from cytology (correlation 97%). The percentage of FNACs that were inadequate for diagnosis was 20%. Review of cytological and histological slides did not lead to any change in the original diagnosis. Our study revealed a cytological-histological discrepancy (2%) in only 4 out of 231 cases over a period of 10 years, due to either a diagnostic or sampling error.

Adolescent↗
PubMed2001

[(123)I]metaiodobenzylguanidine and [(111)In]octreotide uptake in begnign and malignant pheochromocytomas.

Selecting the appropriate approach for resection and follow-up of pheochromocytomas (PCCs) is highly dependent upon reliable localization and exclusion of multifocal, bilateral, or metastatic disease. Metaiodobenzylguanidine (MIBG) scintigraphy was developed for functional localization of catecholamine-secreting tissues. Somatostatin receptor imaging (SRI) has a high sensitivity for localizing head and neck paragangliomas, but studies of intraabdominal PCCs are rare. In this study we review our experience of [(123)I]MIBG and SRI, performed since 1983 and 1989, respectively, in the work-up of primary and recurrent PCCs. Scintigraphic results were correlated with catecholamine secretion, size and site, malignancy, associated tumor syndromes, and morphological features. [(123)I]MIBG scans were performed in a total of 75 patients, in 70 cases before resection of primary PCCs and in 5 cases because of recurrent disease. Ninety-one PCCs were resected. The overall detection rates were 83.3% and 89.8% for PCCs larger than 1.0 cm. Multifocal disease was detected in 4 patients with [(123)I]MIBG. [(123)I]MIBG uptake correlated with greater size of PCC (r = 0.33; P = 0.008) and greater concentration of plasma epinephrine (r = 0.32; P = 0.006). [(123)I]MIBG-negative PCCs (n = 14) had significantly (P = 0.01) smaller diameters than [(123I)]MIBG-positive tumors. Furthermore, [(123)I]MIBG uptake was significantly higher in unilateral (P = 0.02), benign (P = 0.02), sporadic (P = 0.02), intraadrenal (P = 0.02), and capsular invasive (P = 0.03) PCCs than in bilateral, malignant, MEN2A/2B-related, extraadrenal, and noninvasive PCCs, respectively. The detection rate of SRI was only 25% (8 of 32) for primary benign PCCs. In 14 patients metastases occurred, which were effectively visualized with [(123)I]MIBG in 8 of 14 cases. SRI was able to detect metastases in 7 of 8 cases, including 3 [(123)I]MIBG-negative metastatic cases. In addition, [(123)I]MIBG and SRI detected 2 recurrences. In conclusion, [(123)I]MIBG uptake is correlated with the size, epinephrine production, and site of PCCs. Its role in bilateral and MEN2A/2B-related PCCs seems limited. In cases of recurrent elevation of catecholamines, localization of metastases and/or recurrence should be attempted with [(123)I]MIBG scintigraphy. In suspicious metastatic PCCs, SRI might be considered to supplement [(123)I]MIBG scintigraphy.

3-Iodobenzylguanidine↗
PubMed2000

Laparoscopic or conventional Nissen fundoplication for gastro-oesophageal reflux disease: randomised clinical trial. The Netherlands Antireflux Surgery Study Group.

BACKGROUND: For the surgical treatment of gastrooesophageal reflux disease (GORD), laparoscopic Nissen fundoplication has largely replaced the open procedure. Retrospective and prospective non-randomised studies have shown similar results after laparoscopic Nissen fundoplication compared with the open procedure. METHODS: In a multicentre randomised trial candidates for surgical treatment of GORD were randomly assigned to either laparoscopic or open 360 degrees Nissen fundoplication. Primary endpoints were dysphagia, recurrent GORD, and intrathoracic hernia. Secondary endpoints were effectiveness and quality of life. This planned interim analysis focuses on endpoints and complications and in-hospital costs. FINDINGS: At the time of interim analysis, 11 patients in the laparoscopic group and one in the conventional group had reached a primary endpoint (p=0.01; relative risk=8.8, 95% CI 1.2-66.3). This difference was caused mainly by whether or not patients had dysphagia (seven patients in the laparoscopic group and none in the conventional group, p=0.016). INTERPRETATION: Although laparoscopic Nissen fundoplication was as effective as the open procedure in controlling reflux, the significantly higher risk of reaching a primary endpoint in the laparoscopic group led us to stop the study.

Adult↗
PubMed2000

Adult hyperinsulinemic hypoglycemia not caused by an insulinoma: a report of two cases.

Nesidioblastosis is rare in adults and accounts for 0.5-5% of cases of organic hyperinsulinemia. The diagnosis of nesidioblastosis should be considered when peroperative imaging modalities fail to localize a lesion in patients with hyperinsulinism. Two female patients, aged 55 and 16 years, with hyperinsulinemic hypoglycemia are reported. Somatostatin receptor scintigraphy showed slight focal activity in both patients. The first patient underwent a Whipple procedure and became diabetic. The second patient underwent a distal hemi-pancreatectomy and suffered from recurrent hypoglycemic episodes 3 months after surgery, for which she is presently being treated with octreotide. Histological examination of the resected pancreata revealed focally increased islet tissue and a number of slightly hypertrophic beta cells. Such histological abnormalities have been related to functional changes of beta-cells. In infantile nesidioblastosis, a proportion of cases has been associated with mutations in one of several genes. Whether such mutations, leading to hyperinsulinism, also play a role in adult nesidioblastosis is presently unknown.

Adolescent↗
PubMed2000

Peritoneal adhesions to prosthetic materials: choice of mesh for incisional hernia repair.

BACKGROUND: In many cases, incisional hernia repair requires the use of prosthetic materials. The aim of this experimental study in a rat model was to assess the role of polyglactin 910 mesh and fluoropassivated polyester mesh in preventing the formation of adhesions. METHODS: In the first experiment, the formation of peritoneal adhesions was assessed after insertion of polypropylene, polypropylene combined with polyglactin 910, or no mesh. In the second experiment, adhesion formations were compared after insertion of fluoropassivated polyester, polypropylene, and no mesh. RESULTS: The first experiment showed no significant difference in adhesion formations between the polypropylene mesh and the combined mesh; however, when no mesh was used, there were significantly fewer adhesions in both experiments (p < 0.01). The second experiment showed a significantly lower degree of adhesions and a lower Adhesion Index after insertion of fluoropassivated polyester mesh than when polypropylene mesh was used (p = 0.04). CONCLUSIONS: Adding polyglactin 910 mesh to polypropylene mesh to prevent the formation of adhesions is not an effective measure. Fluoropassivated polyester meshes appear to provide a better alternative to the use of polypropylene meshes for incisional hernia repair in humans in terms of the formation of adhesions.

Animals↗
PubMed2000

Intraperitoneal tumor growth is influenced by pressure of carbon dioxide pneumoperitoneum.

BACKGROUND: Several studies have indicated that the carbon dioxide (CO(2)) pneumoperitoneum during laparoscopy plays a role in the pathogenesis of port-site metastases. An experimental animal study was performed to investigate the impact of various pneumoperitoneum pressures on peritoneal tumor growth. METHODS: In this study, 36 male WAG rats were randomized into three groups; two groups with different pneumoperitoneum pressures (16 mmHg and 4 mmHg) and one group of gasless controls. After a pneumoperitoneum of 0.5 x 10(6) ml was established, 531 tumor cells were injected intra-abdominally and the pneumoperitoneum was maintained for 60 min. Peritoneal tumor growth was assessed on day 11 at autopsy. RESULTS: Peritoneal tumor growth in the 16-mmHg group was significantly greater than in the 4-mmHg group (p = 0.039) and the gasless group (p = 0.004). CONCLUSIONS: High-pressure CO(2) pneumoperitoneum stimulates intra-abdominal tumor growth. The use of low insufflation pressures in laparoscopic cancer surgery should be considered.

Animals↗
PubMed2000

Port-site metastases after CO(2) laparoscopy. Is aerosolization of tumor cells a pivotal factor?

BACKGROUND: Animal experiments have shown that carbon dioxide (CO(2)) laparoscopy results in more port-site recurrences than gasless laparoscopy. Possible transport of aerosolized tumor cells by CO(2) was investigated in rats. METHODS: Abdominal cavities of 15 pairs of Wistar Agouti (WAG) rats were connected and 2 x 10(6) or 16 x 10(6) CC 531 cells were injected in the first (donor) rat of each pair. Then 10 l of CO(2) were allowed to flow from the first (donor) to the second (recipient) rat. RESULTS: No tumor was found in the recipients after injection of 2 x 10(6) cells in the donors. Injection of 16 x 10(6) cells in the donors resulted in very limited tumor growth in the recipients. CONCLUSIONS: Aerosolization of tumor cells occurs, but the number of intraperitoneal tumor cells required for metastases to occur by this mechanism is extremely high. Therefore, aerosolization of tumor cells appears not to be of major relevance in the pathogenesis of port-site metastases.

Adenocarcinoma↗
PubMed2000

Losses of chromosomes 1p and 3q are early genetic events in the development of sporadic pheochromocytomas.

Despite several loss of heterozygosity studies, a comprehensive genomic survey of pheochromocytomas is still lacking. To identify DNA copy number changes which might be important in tumor development and progression and which may have diagnostic utility, we evaluated genetic aberrations in 29 sporadic adrenal and extra-adrenal pheochromocytomas (19 clinically benign tumors and 10 malignant lesions). Comparative genomic hybridization was performed using directly fluorochrome-conjugated DNA extracted from frozen (16) and paraffin-embedded (13) tumor tissues. The most frequently observed changes were losses of chromosomes 1p11-p32 (86%), 3q (52%), 6q (34%), 3p, 17p (31% each), 11q (28%), and gains of chromosomes 9q (38%) and 17q (31%). No amplification was identified and no difference between adrenal and extra-adrenal tumors was detected. Progression to malignant tumors was strongly associated with deletions of chromosome 6q (60% versus 21% in clinically benign lesions, P = 0.0368) and 17p (50% versus 21%). Fluorescence in situ hybridization confirmed the comparative genomic hybridization data of chromosomes 1p, 3q, and 6q, and revealed aneuploidy in some tumors. Our results suggest that the development of pheochromocytomas is associated with specific genomic aberrations, such as losses of 1p, 3q, and 6q and gains of 9q and 17q. In particular, tumor suppressor genes on chromosomes 1p and 3q may be involved in early tumorigenesis, and deletions of chromosomes 6q and 17p in progression to malignancy.

Adult↗
PubMed2000

Percutaneous treatment of bile duct stones in patients treated unsuccessfully with endoscopic retrograde procedures.

BACKGROUND: The preferred treatment for stones in the bile duct is endoscopic sphincterotomy followed by stone extraction. When this fails, percutaneous treatment is an alternative to surgery. The purpose of this study was to evaluate the success and complication rate of percutaneous treatment. METHODS: Between April 1990 and April 1997, a total of 31 consecutive patients (20 men, 11 women, mean age 70.1 years) underwent percutaneous treatment of bile duct stones (average of 2.2 per patient, range 1 to 10). The percutaneous treatment was considered successful if all stones could be removed. Time and number of sessions needed for imaging, percutaneous treatment, and complications were scored. RESULTS: Twenty-seven patients (87%) were free of stones after 2 to 15 sessions (mean 5.6). The median time for treatment was 16 days (3 to 299). Complications occurred in 3 of the 31 patients: one myocardial infarction during extracorporeal shockwave lithotripsy, one pancreatitis, and one bacteremia. None of these complications were life threatening. Four patients (13%) underwent surgery after failed percutaneous treatment. CONCLUSION: Percutaneous treatment of bile duct stones is an alternative with a high success rate when endoscopic stone removal fails. Surgery can be avoided in nearly 90% of cases.

Adult↗
PubMed2000

Intraperitoneal polypropylene mesh repair of incisional hernia is not associated with enterocutaneous fistula.

BACKGROUND: Incisional hernia repair with prosthetic material is followed by fewer recurrences than primary repair. Polypropylene is the most commonly used prosthetic material but may cause entero- cutaneous fistulas. The aim of this study was to determine whether enterocutaneous fistulas developed after incisional hernia repair with polypropylene mesh and to evaluate clinical outcome after incisional hernia repair. METHODS: A retrospective analysis of the outcome of incisional hernia repair with polypropylene mesh between 1982 and 1998 was conducted. Follow-up data were obtained from medical records and questionnaires. RESULTS: Polypropylene incisional hernia repair was performed in 136 patients. Median follow-up was 34 months. No enterocutaneous fistulas developed. Wound infection occurred in 6 per cent. Wound sinus formation occurred in two patients. No mesh was removed because of infection and no persisting infection of the mesh occurred. CONCLUSION: Enterocutaneous fistula formation appears to be very rare after incisional hernia repair with polypropylene mesh, regardless of intraperitoneal placement, omental coverage or closing of the peritoneum.

Cutaneous Fistula↗
PubMed2000

Diagnosis and treatment of portal vein thrombosis following splenectomy.

BACKGROUND: Portal vein thrombosis is a rare but potentially fatal complication of splenectomy. The aim of this study was to assess the incidence, risk factors, treatment and outcome of portal vein thrombosis after splenectomy in a large series of patients. METHODS: All patients who had undergone a splenectomy in the University Hospital, Rotterdam, between 1984 and 1997 were reviewed retrospectively. Splenectomy that was followed by symptomatic portal vein thrombosis was selected for analysis. Risk factors for portal vein thrombosis were sought. RESULTS: Of 563 splenectomies, nine (2 per cent) were complicated by symptomatic portal vein thrombosis. All these patients had either fever or abdominal pain. Two of 16 patients with a myeloproliferative disorder developed portal vein thrombosis after splenectomy (P = 0.03), and four of 49 patients with haemolytic anaemia (P = 0.005). Treatment within 10 days after splenectomy was successful in all patients, while delayed treatment was ineffective. CONCLUSION: Portal vein thrombosis should be suspected in a patient with fever or abdominal pain after splenectomy. Patients with a myeloproliferative disorder or haemolytic anaemia are at higher risk; they might benefit from early detection and could have routine Doppler ultrasonography after splenectomy.

Adolescent↗
PubMed2000

Laparoscopic detection and resection of insulinomas.

BACKGROUND: Laparoscopic ultrasonography as a diagnostic tool for the localization of islet cell tumors has been described before, but few reports on laparoscopic resection of insulinomas exist. We retrospectively reviewed the results of our experience with laparoscopic detection and the resection of insulinomas to determine its feasibility. METHODS: Between February 1996 and February 1999, 10 patients underwent operation for organic hyperinsulinism at our institution. Patient and clinical characteristics were studied retrospectively. Laparoscopic ultrasonography was performed to localize the insulinoma and then laparoscopic resection was performed. RESULTS: Eight women and 2 men underwent operation for hyperinsulinism. In 6 patients the insulinoma could be resected laparoscopically, either by enucleation (5 patients) or by resection of the pancreatic tail (1 patient). Four procedures were converted to laparotomy for the proximate location of the insulinoma to the portal vein or pancreatic duct (3 procedures) and failure to identify the insulinoma (1 procedure). The overall success rate of preoperative localization of an insulinoma with the use of various imaging techniques was 60% (6/10 patients). Laparoscopic ultrasonography could identify an insulinoma in 90% of the patients (9/10 patients). The median hospital stay was 7 days. CONCLUSIONS: Laparoscopic ultrasonography followed by laparoscopic removal of the insulinoma in patients with clinically manifested hyperinsulinism is a feasible and safe technique with low morbidity and fast postoperative recovery. Preoperative localization studies appear of limited value.

Adolescent↗
PubMed2000

Endoscopic retroperitoneal adrenalectomy: lessons learned from 111 consecutive cases.

OBJECTIVE: To evaluate the effectiveness of endoscopic retroperitoneal adrenalectomy (ERA). SUMMARY BACKGROUND DATA: Minimally invasive adrenalectomy has become the procedure of choice for benign adrenal pathology. Although the adrenal glands are located in the retroperitoneum, most surgeons prefer the transperitoneal laparoscopic approach to adrenal tumors. METHODS: Clinical characteristics and outcomes of 111 ERAs from January 1994 to December 1999 were evaluated. RESULTS: Ninety-five patients underwent 111 ERAs (79 unilateral, 16 bilateral). Indications were Cushing syndrome (n = 22), Cushing disease (n = 8), ectopic adrenocorticotropic hormone syndrome (n = 6), Conn's adenoma (n = 25), pheochromocytoma (n = 19), incidentaloma (n = 11), and other (n = 4). Tumor size varied from 0.1 to 8 cm. Median age was 50 years. Unilateral ERA required 114 minutes, with median blood loss of 65 mL. Bilateral ERA lasted 214 minutes, with median blood loss of 121 mL. The conversion rate to open surgery was 4.5%. The complication rate was 11%. Median postoperative hospital stay was 2 days for unilateral ERA and 5 days for bilateral ERA. The death rate was 0.9%. At a median follow-up of 14 months, the recurrence rate of disease was 0.9%. CONCLUSION: For benign adrenal tumors less than 6 cm, ERA is recommended.

Adolescent↗
PubMed1999

[Laparoscopic splenectomy for hematological diseases; results in 28 patients].

OBJECTIVE: To evaluate the first results of laparoscopic splenectomy for haematological diseases and the learning curve. DESIGN: Retrospective. PATIENTS AND METHODS: Data of all patients who underwent a laparoscopic splenectomy in October 1994-July 1998 in the University Hospital Rotterdam, Department of surgery, the Netherlands, were collected from electronic databases. Data on postoperative complications were collected from medical records. Patients with splenomegaly (> 15 cm) were not eligible for the procedure. RESULTS: 28 patients were eligible for a laparoscopic splenectomy. The male:female ratio was 1:4. The mean age was 35 years. The indications for surgery were idiopathic thrombocytopenic purpura (ITP; n = 24), Gilbert syndrome (n = 1), spherocytosis (n = 1), thalassaemia (n = 1) and haemolytic anaemia with ITP (n = 1). Conversion to an open procedure was necessary in 5 of 28 laparoscopic splenectomies (18%). The median operating time was 172 minutes. Complications occurred in four patients: pneumonia (n = 2), bleeding (n = 1) and urosepsis (n = 1). The median hospital stay was 5 days (range: 1-18). The first 14 laparoscopic splenectomies differed from the following 14 by a higher conversion rate (p = 0.01), a longer operation time (p = 0.002) and a longer hospital stay (p = 0.004). In 23 out of 25 patients with ITP the thrombocyte count became normal. CONCLUSION: Laparoscopic splenectomy is associated with a learning curve, with a high incidence of conversion in the early procedures. It appears to be a safe and effective operation.

Adolescent↗
PubMed1999

[Laparoscopic donor nephrectomy for kidney transplants from living family members: good preliminary results].

OBJECTIVE: Evaluation of safety and technical feasibility of laparoscopic live donor nephrectomy. DESIGN: Descriptive. METHOD: The per- and postoperative results were analysed of 15 patients subjected to laparoscopic live donor nephrectomy in the Erasmus Medical Centre Rotterdam, Dept. of General Surgery, the Netherlands. Both left and right nephrectomy were performed via the transperitoneal route. The kidney was removed via a subumbilical incision. RESULTS: Laparoscopic donor nephrectomy was attempted in 15 patients and completed successfully in 14. Conversion to flank incision was resorted to one patient because of a venous bleeding. Median operating time was 290 min (SD: 57). Mean warm ischaemia time was 7 min (range: 4-17), including laparoscopic harvest. All kidneys were functioning well after transplantation. The mean duration of postoperative hospitalization of the donors was 4 days. CONCLUSION: Laparoscopic live donor nephrectomy is a safe and technically feasible procedure in a kidney transplant programme involving a living relative.

Adult↗