Biomedical subjects

W F Weidema

Publications and source records attributed to W F Weidema.

At least 19 recordsLinked to original sources

PubMed2005

Totally extraperitoneal repair for bilateral inguinal hernia: does mesh configuration matter?

BACKGROUND: The endoscopic preperitoneal approach has numerous advantages for the reconstruction of bilateral inguinal hernias. Repair may be achieved using either one large or two small meshes. The aim of this study was to investigate whether one of the techniques was superior in terms of recurrence and complication rate. METHODS: Data obtained from 113 patients who underwent surgery between January 1998 and December 2001 was reviewed. For the sake of this study, 86% of all patients were examined for hernia recurrence at an additional outpatient visit. RESULTS: The findings showed recurrence rates, of 3.5% for single mesh and 3.7% for double mesh. This difference was not significant. Complication rates did not differ significantly between the groups. CONCLUSIONS: Endoscopic preperitoneal bilateral hernia repair is a safe and reliable technique in the hands of experienced surgeons. The rate of hernia recurrence and complications is low and independent of the mesh configuration (single or double). Mesh configuration based on personal preference is permissible.

Adult↗

PubMed2005

Long-term follow-up after umbilical hernia repair: are there risk factors for recurrence after simple and mesh repair.

Adult umbilical hernia is a common surgical condition mainly encountered in the fifth and sixth decade of life. Despite the high frequency of the umbilical hernia repair procedure, disappointingly high recurrence rates, up to 54% for simple suture repair, are reported. Since both mesh and suture techniques are used in our clinic we set out to investigate the respective recurrence rates and associated complications, retrospectively. Patients who were treated between January 1998 and December 2002 were identified from our hospital database and invited to attend the outpatient department for an extra follow-up, history taking and physical examination. The use of prosthetic material, occurrence of surgical site infection, body mass and height as well as recurrence were recorded at the time of this survey. In total, 131 consecutive patients underwent operative repair of an umbilical hernia. Twenty-eight percent of the patients were female (n = 37). In 12 patients (11%) umbilical hernia repair was achieved with mesh implantation. Fourteen umbilical hernia recurrences were noted (13%); none had been repaired using mesh. No relationship was found between wound infection or obesity and umbilical hernia recurrence. In the light of these results it is necessary to re-evaluate our clinical "guidelines" on mesh placement in umbilical hernia repair: apparently not every umbilical fascial defect needs mesh repair. Research should focus on establishing risk factors for hernia recurrence.

Adult↗

PubMed2004

Long-term results after modified Gallie technique for incisional hernia repair: results in 19 patients.

BACKGROUND: A modified forgotten technique for repairing large incisional hernias is described together with its long-term results in 19 patients. A synthetic mesh with 1-cm wide spokes radiating from the mesh is placed preperitioneally, overlapping the fascial defect. The spokes are pulled through rectus sheaths and muscle and sutured ventrally, thereby creating a solid reconstruction withstanding shrinking of the mesh. METHOD: Nineteen patients were operated on (13 primary incisional hernia, minimal fascial defect 10 cm). Notes on patients were reviewed, and the patients were contacted for follow-up examination. RESULTS: No major complications occurred. After a median of 49 months, 17 patients were reviewed at the outpatient clinic. Two possible recurrences were detected, of which one was operated on. This proved to be bulging of the mesh, resulting in a recurrence of 1 out of 17 (6%). CONCLUSION: From these results, it is concluded that Gallie's technique using synthetic mesh is a safe and effective repair for incisional hernia and deserves more attention, especially for large fascial defects.

Aged↗

PubMed1999

Endoscopic total extraperitoneal repair of primary and recurrent inguinal hernias.

BACKGROUND: In most reports different techniques have been described for combinations of primary and recurrent hernias. The aim of this study was to investigate and compare the results of endoscopic total extraperitoneal repair (TEP) of primary and recurrent inguinal hernias. METHODS: From January 1993 to July 1995, 221 patients with an unilateral inguinal hernia (186 primary and 35 recurrent) underwent TEP repair. Follow-up, including physical examination, was performed at regular 3-month intervals. RESULTS: The mean operation time was 37.6 min. Minor perioperative complications occurred in 23 cases. Conversion was required for 16 patients (7.2%). Postoperative complications were reported for 11.7% of the patients. Hospital stay was short. Mean follow-up was 40.4 months. The recurrence rate was 3. 2% for primary hernias and 20% for recurrent hernias. CONCLUSIONS: This study confirms the preliminary success of TEP for primary inguinal hernia repair, as previously reported. The high recurrence rate after endoscopic repair of recurrent hernias needs to be studied further.

Adult↗

PubMed1999

Laparoscopic repair of recurrent inguinal hernias after endoscopic herniorrhaphy.

BACKGROUND: Although the recurrence rate for endoscopic herniography is low (0-3%), it is still debatable whether these recurrences should be corrected laparoscopically or by the conventional method. The aim of this study was to investigate whether these recurrences can be repaired by means of the laparoscopic approach with acceptable complication and recurrence rates. METHODS: From October 1992 to December 1997, 34 patients with recurrent inguinal hernias at physical examination underwent surgery at our institutions. All the recurrences occurred following endoscopic inguinal hernia repair with mesh prostheses. The recurrences were repaired endoscopically using a transabdominal approach. Depending on the size of the defect, a new polypropylene mesh was used. RESULTS: Mean surgery time was 69 min. There were no conversions to the anterior approach. After a mean follow-up of 35 months, no recurrences had been diagnosed. CONCLUSION: The transabdominal preperitoneal approach is a reliable technique for recurrent inguinal hernia repair after previous endoscopic herniorrhaphy.

Adult↗

PubMed1999

Endoscopic totally extraperitoneal repair of bilateral inguinal hernias.

BACKGROUND: Recurrence rates associated with bilateral inguinal hernia repair with a giant prosthesis (Stoppa procedure) are low. Endoscopic totally extraperitoneal bilateral inguinal hernia repair with a giant prosthesis combines the low recurrence rate of the Stoppa repair and the advantages of minimally invasive surgery. The aim of this retrospective study was to investigate whether extraperitoneal bilateral inguinal hernia repair could be performed by the minimally invasive, totally extraperitoneal approach. METHODS: From February 1993 to January 1998, 98 patients with bilateral inguinal hernias underwent surgery. A polypropylene 30 x 10 cm rectangular mesh or a 30 x 10/15 cm 'slipmesh' was used. Follow-up, including a physical examination, of 96 per cent of patients was performed. RESULTS: Median operative time was 60 min. Mostly minor intraoperative complications occurred. Conversion was required for two patients. Apart from one patient with a necrotic fasciitis who died from respiratory failure, only minor postoperative complications (10 per cent) occurred. Median hospital stay was 1 (range 1-21) days. Median recuperation time was 5 (range 1-22) days. Median follow-up (96 per cent) was 32 (range 7-57) months; there were six recurrences among 34 hernias in the group of 17 patients treated with 10 x 30 cm mesh and two (1 per cent) in the group that received 30 x 10/15 cm mesh (162 hernias in 81 patients). CONCLUSION: The endoscopic approach for the Stoppa procedure for bilateral inguinal hernia repair is a reliable method with minor complications. It ensures a short recuperation time and the recurrence rate is low owing to adequate overlap of the hernial defect when a 'slipmesh' is used.

Adult↗

PubMed1998

CD44 splice variants as prognostic markers in colorectal cancer.

BACKGROUND: Splice variants of CD44 play a causal role in the metastatic spread of pancreatic carcinoma in the rat. In previous studies we have shown that homologues of these CD44 isoforms (CD44v6) are overexpressed during colorectal tumorigenesis in man and that CD44v6 overexpression is associated with an unfavorable prognosis in this disease. In the present study we have assessed the prognostic significance of CD44 variants containing exon v5. In addition, we have used a panel of different antibodies against CD44v6 and applied a combined scoring system to improve its value as prognosticator. METHODS: Expression of CD44 variants was studied by immunohistochemistry on frozen tissue sections, and the prognostic value of the CD44 variant expression was assessed using univariate and multivariate analysis. RESULTS: Our studies show that expression of CD44v6, but not CD44v5, has significant prognostic value. Analysis of CD44v6 expression by means of a combined scoring system, on the basis of a panel of three different monoclonal antibodies (mAbs), makes CD44v6 a highly significant prognostic marker that is independent of Dukes stage, tumor grade, or tumor localization. CONCLUSION: Assessment of CD44v6 expression by a combination of mAbs yields an independent prognosticator that may be of value in identifying patients with a high propensity to develop distant metastasis.

Adult↗

PubMed1997

Comparison of conventional anterior surgery and laparoscopic surgery for inguinal-hernia repair.

BACKGROUND: Inguinal hernias can be repaired by laparoscopic techniques, which have had better results than open surgery in several small studies. METHODS: We performed a randomized, multicenter trial in which 487 patients with inguinal hernias were treated by extraperitoneal laparoscopic repair and 507 patients were treated by conventional anterior repair. We recorded information about postoperative recovery and complications and examined the patients for recurrences one and six weeks, six months, and one and two years after surgery. RESULTS: Six patients in the open-surgery group but none in the laparoscopic-surgery group had wound abscesses (P=0.03), and the patients in the laparoscopic-surgery group had a more rapid recovery (median time to the resumption of normal daily activity, 6 vs. 10 days; time to the return to work, 14 vs. 21 days; and time to the resumption of athletic activities, 24 vs. 36 days; P<0.001 for all comparisons). With a median follow-up of 607 days, 31 patients (6 percent) in the open-surgery group had recurrences, as compared with 17 patients (3 percent) in the laparoscopic-surgery group (P=0.05). All but three of the recurrences in the latter group were within one year after surgery and were caused by surgeon-related errors. In the open-surgery group, 15 patients had recurrences during the first year, and 16 during the second year. Follow-up was complete for 97 percent of the patients. CONCLUSIONS: Patients with inguinal hernias who undergo laparoscopic repair recover more rapidly and have fewer recurrences than those who undergo open surgical repair.

Activities of Daily Living↗

PubMed1996

The learning curve for totally extraperitoneal laparoscopic inguinal hernia repair.

BACKGROUND: Several laparoscopic techniques have been introduced to re pair inguinal hernia, the newest and most promising being a totally extraperitoneal approach. Nevertheless, the surgeon may encounter several complications and technical difficulties associated with the transition from the conventional anterior operation. METHODS: In late 1993 and 1994, 120 patients were operated on for inguinal hernia using the totally extraperitoneal approach by four laparoscopic surgeons inexperienced in this new technique in a secondary referral setting. Their learning curve was assessed through operation time, perioperative and postoperative complications, and technical difficulties. RESULTS: Median operative time decreased significantly (P = 0.0003) when going through the learning curve. During the initial part of the learning curve, conversion to another technique was necessary in 10 (8%) cases, and in 6 of these cases, conversion was needed for a peritoneal tear (relative risk for conversion if peritoneal tear was present: 4.0; 95% confidence interval 1.2 to 13.1, P = 0.025). The median operative time for Nyhus type IIIb and IVb hernias was significantly longer than for other types (70 versus 55 minutes, P = 0.003). Median postoperative stay was 2 days (range 0 to 7). There were 10 recurrences within 6 months due to technical or judgement errors. CONCLUSIONS: For surgeons, the learning curve for totally extraperitoneal laparoscopic hernia repair can be overcome; however, the presence of an experienced surgeon during the procedure is vital, as this may prevent unnecessary recurrences.

Adolescent↗

PubMed1995

Difference in expression of CD44 splice variants between proximal and distal adenocarcinoma of the large bowel.

To help determine whether adenocarcinomas of the proximal and distal large bowel reflect distinct entities, the expression of two splice variants of the metastasis-associated cell adhesion molecule CD44, carrying exons v5 and v6 respectively, was investigated retrospectively in fresh frozen samples of 23 proximal and 41 distal carcinomas by immunohistochemical staining with specific anti-CD44v5 monoclonal antibody VFF8 and anti-CD44v6 monoclonal antibodies VFF4 and VFF7. Tumours were staged as: Dukes A, 0; Dukes B, 27; Dukes C, 31; and Dukes 'D', six. Compared with distal tumours, proximal lesions expressed significantly more CD44v5 (96 versus 87 per cent, P = 0.02) and CD44v6 (83 versus 61 per cent, P = 0.01). CD44v5 and CD44v6 are considered markers for tumour progression and aggressive behaviour. Their high expression in proximal carcinomas seems to contrast with the general belief that these tumours show less aggressive behaviour than left-sided lesions. Further study of the biological significance of the expression of CD44 splice variants is therefore needed.

Adenocarcinoma↗

PubMed1994

Colorectal cancer prognosis and expression of exon-v6-containing CD44 proteins.

CD44 variants containing v6 confer metastatic potential to rat carcinoma cell-lines. In man, CD44v6 is increasingly expressed during colorectal tumour progression. In 68 colorectal carcinoma patients, survival analysis showed that CD44v6 expression in the tumours was associated with tumour-related death. In patients who had an apparently radical resection of their primary tumour, CD44v6 expression had prognostic value independent of Dukes' stage. CD44v6 expression may reflect propensity for metastasis after apparently curative surgery, making adjuvant therapy an option in these patients.

Carrier Proteins↗

PubMed1993

Initial experience with laparoscopic fundoplication in The Netherlands and comparison with an established technique (Belsey Mark IV).

Since the introduction of laparoscopic cholecystectomy as an alternative for conventional cholecystectomy, the number of cholecystectomies per year is showing an increased tendency, suggesting that indications for surgery have broadened now that the morbidity of the procedure has decreased so much. For gastro-oesophageal reflux disease (GORD) the current number of operations performed per year in The Netherlands is small compared with the calculated prevalence of complicated GORD. If the data on epidemiology of GORD by Richter are extrapolated to the population of The Netherlands, there must be at least 4,500 potential candidates for antireflux surgery currently available and only 250 operations are performed per year. Laparoscopic Nissen fundoplication is practised with acceptable results. If with this new development the same tendency as for laparoscopic cholecystectomy arises, this may mean either that too many patients will undergo antireflux surgery or that the potential candidates will now get their chance to have an effective operation with the prospect of low procedure-related morbidity. In The Netherlands, 62 laparoscopic Nissen fundoplications have been performed. There have been no deaths and in 5 patients the laparoscopic procedure had to be converted into a laparotomy. Forty-two of these 62 patients were treated according to a protocol and were included in the follow-up. At one month, 38 out of 42 patients were available for follow-up. At one month after surgery, 38 patients felt that their reflux symptoms had improved. Surgery-induced symptoms were present in 19 out of 38 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1989

Granular cell tumor of the breast.

Three cases of granular cell tumor of the breast are reported. Granular cell tumor of the breast is a rare benign tumor with a malignant appearance both clinically, radiologically and macroscopically. The cytology is quite characteristic although the tumor clinically often resembles a carcinoma. Frozen section can be misinterpreted, unnecessary mastectomy or axillary dissection can be prevented by careful cytological examination.

Aged↗

PubMed1989

Peri-operative blood transfusions in colorectal cancer.

Clinical studies report reduced recurrence-free survival and increased cancer-related death after surgical treatment for cancer, when peri-operative blood transfusions were given. In this study we collected transfusion data of 212 patients who participated in a prospective study of two different resection techniques for colorectal cancer. One hundred and fifty-eight patients were transfused and 54 were not. The follow-up period for almost all patients was 5 years. The 5-year survival rate was 52% both for the transfused patients and the nontransfused patients. For subgroups of patients with Dukes' B and Dukes' C tumours no statistically significant differences were found. In the group of patients that were transfused the number of transfusions did not affect survival. In this study we could not confirm the deleterious effect of peri-operative blood transfusions on survival.

Blood Transfusion↗

PubMed1988

Proximal femoral fractures in conjunction with hemiarthroplasty according to Moore.

During a period of six years, 245 hemiarthroplasties according to Moore were implanted for fractures with dislocation of the femoral neck. In five patients (2%) proximal ipsilateral fractures of the femur occurred in the postoperative phase. All fractures were located near the tip of the prosthesis. Four were spiral fractures, one was a communitive fracture. Four patients were treated with plating, one with screw fixation. Two patients were unable to walk, two patients were able to walk with help and one walked without help. Classification of fractures distal to an endoprosthesis and operative modalities are discussed.

Aged↗

PubMed1987

Sodium transport in a mouse model of colonic carcinogenesis.

Following 4 weeks of s.c. injections of 1,2-dimethylhydrazine, a carcinogen that produces colon cancer in CF1 mice, an increase in the unidirectional mucosal to serosal flux and net absorption of sodium was observed in the distal colon. This increase in sodium transport was amiloride sensitive. 1,2-Dimethylhydrazine treatment had no effect on sodium transport in the distal colon of DBA/2 mice, a strain which does not develop colonic malignant transformation. Although stimulation of sodium transport has been observed in cultured cell systems exposed to growth factors, similar changes in sodium transport have not previously been demonstrated in an intact epithelium at an early stage of carcinogenesis. The present study in mouse distal colon demonstrates that sodium transport is altered in 1,2-dimethylhydrazine-induced malignant transformation of the large bowel.

1,2-Dimethylhydrazine↗

PubMed1986

Transmural electrical potential difference as an early marker in colon cancer.

It has been suggested that relative depolarization of the cell membrane occurs during carcinogenesis. A study was undertaken to determine the effect on the colonic transmural potential difference in CF1 mice following the administration of a carcinogen, a cytotoxic agent, and bile acids. Depolarization of the distal colonic mucosa was seen in mice treated with the carcinogen but not with the cytotoxic agent, and bile acids caused further depolarization of the mucosa. These experiments support the hypothesis that epithelial depolarization is a putative mechanism in carcinogenesis, which could have important implications for the early detection of colon cancer.

Animals↗

PubMed1986

Recolonization and colonization resistance of the large bowel after three methods of preoperative preparation of the gastrointestinal tract for elective colorectal surgery.

The impact of three current types of preoperative large bowel preparation on the microbial flora and the colonization resistance (CR) was investigated in 15 volunteers. In the first group a whole gut irrigation was performed without administration of antibiotics (group WGI). In the second group 0.5 g/l metronidazole and 1 g/l neomycin was added to the irrigation fluid (group WGI + AB). A whole gut irrigation with prior oral administration of 1 l mannitol 10% was performed in the third group. The antibiotic prophylaxis in this group consisted of two doses of 80 mg gentamicin i.v. and 500 mg metronidazole orally 24 h after lavage (group Mann + AB). One hour after the mechanical cleansing procedure was finished all volunteers were orally contaminated with one dose of an Escherichia coli test strain. The aerobic faecal reduction due to the cleansing procedure was 2-3 logs, while for the anaerobes it was 4-5 logs. The anaerobic flora in group WGI recovered within 24 h, while the aerobes showed a transient 'overgrowth' for the period of 2 days. The overgrowth of aerobes in group WGI + AB was observed for more than a week and the total numbers of aerobes started gradually to decline after the anaerobic flora had reached pretreatment levels at day three or four. Despite the normal numbers of anaerobes present 24 h after treatment, overgrowth of E. coli was seen in the group Mann + AB, probably due to residual mannitol left in the intestinal tract. The test strain of E. coli was excreted for a period of 1 week by the volunteers in the groups WGI and Mann + AB, but it was isolated for more than 10 weeks in the group WGI + AB. It is thought that all three methods of preoperative large bowel preparation decreased the CR of the gastrointestinal tract because of a disturbance of the interaction between aerobic and anaerobic microorganisms and alterations of the colonic wall. The anaerobic microflora, however, appeared to be primarily responsible for the maintenance of the CR. Antimicrobial prophylaxis should consist of a high dose, short term, systemic antibiotic regimen, not only because an adequate serum level of an appropriate drug at the time of operation substantially decreases the incidence of postoperative septic complications but also because a systemic regimen scarcely influences the CR of the gastrointestinal tract. beta-Aspartylglycine appeared to be a specific but not very sensitive marker for decreased CR.

Adult↗