Michael Gerhards - Academia.edu (original) (raw)
Papers by Michael Gerhards
The Lancet Gastroenterology & Hepatology, Aug 1, 2019
Take-down policy If you believe that this document breaches copyright please contact us providing... more Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.
Hpb, Apr 1, 2016
81.2% mild); jaundice was observed in 62 patients. Preoperative radiologic imaging was done in 43... more 81.2% mild); jaundice was observed in 62 patients. Preoperative radiologic imaging was done in 43 patients (CT scan in 7.1%, MRI in 31.3%). There were 70 transcystic and 42 transductal choledochoscopies with a median IQR operative time of 77.5 (110e65) vs. 122.5 (140e94) minutes, p < 0.001. T-tubes were placed only in 13 (11.5%) patients. Complete clearance of the bile duct was achieved in 91.1% leading to a conversion rate of 2.7%; in 6.2% of cases additional postoperative ERCP was performed. Readmission and ERCP for missed stones was needed in 3.6% of all cases. The overall postoperative complication rate reached 6.3%. The median IQR overall hospital stay was 9 (14e7) days. Conclusions: One-stage surgical approach is rational in the management of patients with a high risk of CBD stones.
Keighley & Williams’ Surgery of the Anus, Rectum and Colon, 2018
Nederlands tijdschrift voor geneeskunde, 2010
Haemorrhoids occur in approximately 30% of the population. Commonly occurring complaints include ... more Haemorrhoids occur in approximately 30% of the population. Commonly occurring complaints include blood loss, pruritus, hygiene problems and soiling. A high-fibre diet, with dietary-fiber supplementation if required, often resolves the symptoms. When symptoms are not resolved, the next step is rubber band ligation: a safe and easy procedure. In the long term, the result of rubber band ligation is often unsatisfactory. Haemorrhoidectomy was formerly the only alternative. Haemorrhoidectomy can be accompanied by serious complications, such as disabling pain and incontinence. Haemorrhoidectomy was therefore considered obsolete by the Dutch Institute for Healthcare Improvement (CBO) guideline of 1994. Today new operative procedures are available: Doppler-guided haemorrhoidal artery ligation (DG-HAL) and stapled anopexy. Both techniques are safe and yield good results. Moreover, these techniques cause little postoperative pain. DG-HAL and stapled anopexy offer an alternative for patients w...
The Netherlands journal of medicine, 2011
Surgical Endoscopy, 2012
Background Risk factors for conversion in cholecystectomy may be of clinical value. This study ai... more Background Risk factors for conversion in cholecystectomy may be of clinical value. This study aimed to investigate whether a set of risk factors, including the surgeon's specialization, can be used for the development of a preoperative strategy to optimize conversion outcome. Methods The data for all patients who underwent laparoscopic cholecystectomy at a single institution between January 2004 and December 2008 were retrospectively reviewed. Factors predictive for conversion were identified, and a preoperative strategy model was deduced. Results Of the 1,126 patients analyzed, 106 (9%) underwent laparoscopic cholecystectomy in an emergency setting. Delayed surgery was performed for 63 (46%) of 138 patients (12%) with acute cholecystitis. Preoperative endoscopic retrograde cholangiography was achieved for 161 of the patients (14%). Risk factors predictive of conversion (for 65 patients) were male gender [odds ratio (OR), 2.3; 95% confidence interval (CI), 1.3-3.9; p = 0.004], age older than 65 years (OR, 2.6; 95% CI, 1.4-4.8; p = 0.002), body mass index (BMI) exceeding 25 kg/m 2 (OR, 3.4; 95% CI, 1.7-7.1; p \ 0.001), history of complicated biliary disease (HCBD) (OR, 5.6; 95% CI, 3.2-9.8; p = \ 0.001), and surgery by a non-gastrointestinal (non-GI) surgeon (OR, 4.9; 95% CI, 2.2-10.6; p \ 0.001). The conversion rate for patients with a history of no complications who had two or more risk factors (gender, age, BMI [ 25) and for patients with a HCBD who had one or more risk factors was significantly higher if the surgery was performed by non-GI rather than GI surgeons. Conclusion Male gender, age older than 65 years, BMI exceeding 25 kg/m 2 , HCBD, and surgery by a non-GI surgeon are predictive for conversion. A preoperative triage for surgeon selection based on risk factors and a HCBD is proposed to optimize conversion outcome.
Radiology, 2007
To prospectively compare in a multicenter study the agreement between endoanal magnetic resonance... more To prospectively compare in a multicenter study the agreement between endoanal magnetic resonance (MR) imaging and endoanal ultrasonography (US) in depicting external anal sphincter (EAS) defects in patients with fecal incontinence. The study was approved by the medical ethics committee of all participating centers. A total of 237 consenting patients (214 women, 23 men; mean age, 58.6 years +/- 13 [standard deviation]) with fecal incontinence were examined from 13 different hospitals by using endoanal MR imaging and endoanal US. Patients with an anterior EAS defect depicted on endoanal MR images and/or endoanal US scans underwent anal sphincter repair. Surgical findings were used as the reference standard in the determination of anterior EAS defects. The Cohen kappa statistic and McNemar test were used to calculate agreement and differences between diagnostic techniques. Agreement between endoanal MR imaging and endoanal US was fair for the depiction of sphincter defects (kappa = 0.24 [95% confidence interval: 0.12, 0.36]). At surgery, EAS defects were found in 31 (86%) of 36 patients. There was no significant difference between MR imaging and US in the depiction of sphincter defects (P = .23). Sensitivity and positive predictive value were 81% and 89%, respectively, for endoanal MR imaging and 90% and 85%, respectively, for endoanal US. In the selection of patients for anal sphincter repair, both endoanal MR imaging and endoanal US are sensitive tools for preoperative assessment, and both techniques can be used to depict surgically repairable anterior EAS defects.
International Journal of Radiation Oncology*Biology*Physics, 2010
Biological, physical and clinical aspects of cancer treatment with ionising radiatio
European Journal of Gastroenterology & Hepatology, 2013
Digestive Surgery, 2009
Background/Aims: Procedures for haemorrhoidal prolapse that maintain functional haemorrhoidal ana... more Background/Aims: Procedures for haemorrhoidal prolapse that maintain functional haemorrhoidal anatomy are progressively used. The procedure for prolapse and haemorrhoids (PPH) has advantages over conventional haemorrhoidectomy, but is associated with a higher recurrence rate. The feasibility and efficiency of a second PPH instead of haemorrhoidectomy in case of recurrent symptoms were studied. Methods: A retrospective chart review was conducted of all patients that were treated with PPH for haemorrhoidal prolapse in our hospital between May 2002 and November 2008. All patients in need for a second PPH because of persistent or recurrent symptoms of prolapse were identified and analyzed. Results: Out of 137 patients who underwent a PPH, 22 patients (16%) were in need of a reoperation for symptoms of prolapse. Of these, 12 (55%) were treated with a second PPH. Successful prolapse reduction was achieved in 11 out of 12 patients. No postoperative complications were encountered during a m...
Colorectal Disease, 2012
Comparison of functional and surgical outcome of the J-pouch with the side-to-end coloanal anasto... more Comparison of functional and surgical outcome of the J-pouch with the side-to-end coloanal anastomosis after preoperative radiotherapy and total mesorectal excision in rectal cancer patients. In a multicentre study, patients with a carcinoma of the lower two-thirds of the rectum were randomized to either a J-pouch or a side-to-end reconstruction. Primary outcome was function of the neorectum 1 year after surgery. A functional outcome [COloREctal Functional Outcome (COREFO)] questionnaire, and two quality of life questionnaires (EORTC-QLQ-CR38 and SF-36) were to be completed by all participants preoperatively, and 4 and 12 months postoperatively. Independent data managers recorded surgical outcome. A group size of 30 patients in each group was calculated based on a 15-point difference of the COREFO scale. In total, 107 patients were randomized, 55 in the J-pouch group and 52 in the side-to-end anastomosis group. The COREFO incontinence scale at 4 months and the total functional outcome at 4 and 12 months showed better results for the J-pouch group in comparison with the side-to-end anastomosis group. The remaining COREFO scales (frequency, social impact, stool-related aspects and bowel medication), surgical outcome (complications, reoperations, length of hospital stay, readmissions and mortality) and quality of life did not show significant differences between treatment groups. The overall results of a coloanal J-pouch and a side-to-end anastomosis are comparable, although functional results are slightly better with a J-pouch. The side-to-end anastomosis is technically less demanding and therefore a justified alternative in sphincter-saving surgery.
Colorectal Disease, 2012
The procedure for prolapse and haemorrhoids (PPH) is an effective surgical therapy for symptomati... more The procedure for prolapse and haemorrhoids (PPH) is an effective surgical therapy for symptomatic haemorrhoids. Compared with haemorrhoidectomy, meta-analysis has shown PPH to be less painful, with higher patient satisfaction and a quicker return to work, but at the cost of higher prolapse recurrence rates. This is the first report describing predictors of prolapse recurrence after PPH. A cohort of patients with symptomatic haemorrhoids, treated with PPH in our hospital between 2002 and 2009, was retrospectively analysed. Multivariate analysis was performed to identify patient-related and perioperative predictors associated with persisting prolapse and prolapse recurrence. In total, 159 consecutively enrolled patients were analysed. Persistence and recurrence of prolapse was observed in 16% of the patients. Increased surgical experience showed a trend towards lower recurrence rates. Multivariate analysis identified female gender, long duration of PPH surgery and the absence of muscle tissue in the resected specimen as independent predictors of postoperative persistence of prolapse of haemorrhoids. The absence of prior treatment with rubber band ligation (RBL) as well as increased PPH experience at the hospital showed a trend towards a higher rate of prolapse recurrence. In order to reduce recurrence of prolapse, PPH should be performed by a surgeon with adequate PPH experience, patients should be treated with RBL prior to PPH and a resection of mucosa with underlying muscle fibres should be strived for.
Colorectal Disease, 2014
As a result of their extent and complexity, pelvic wounds after surgery for anorectal malignancy ... more As a result of their extent and complexity, pelvic wounds after surgery for anorectal malignancy often require a multidisciplinary approach to accomplish closure. This report describes a successful reconstruction using the lotus petal perforator flap. This flap is based on perforators of the internal pudendal artery and was partially depithelialized for plugging the defect. Wound healing was achieved after 12 days. The lotus petal flap is a relatively simple and successful choice for reconstruction of an extended chronic presacral defect after radiotherapy and rectal cancer resection.
Colorectal Disease, 2009
Continent ileostomy (CI) after proctocolectomy is an alternative technique compared to an ileal p... more Continent ileostomy (CI) after proctocolectomy is an alternative technique compared to an ileal pouch-anal anastomosis (IPAA). The question arises as to whether this technique is valuable. The aim of this study was to evaluate the role of the continent ileostomy, by patient follow-up satisfaction and quality of life assessment. Twenty-eight patients with a continent ileostomy operated between 1996 and 2007 were compared with patients who received an IPAA or a conventional ileostomy. SF-36 and EORTC QLC-CR38 questionnaires and a specific continent ileostomy questionnaire were used to assess differences and patient satisfaction. The quality of life in patients with a CI is not significant better or worse than patients with either a conventional ileostomy or an IPAA. On three scales (sexual enjoyment, gastro-intestinal tract symptoms and male sexual problems) statistically significant differences were reported. Overall, nearly all patients are very satisfied with the CI. All patients would make the same decision again and would recommend this procedure to other patients. The continent ileostomy remains to be a suitable alternative for the preservation of continence after a proctocolectomy, especially when an ileal pouch-anal anastomosis is not an option. If a choice has to be made between a CI and conventional ileostomy good preoperative counselling is necessary to make a well founded decision. To minimize complications, these procedures have to be performed in centres with specific expertise. Therefore, knowledge about the CI should be preserved for the future.
European Journal of Surgical Oncology
European Journal of Surgical Oncology
Dates of consent of participating centres.
The Lancet Gastroenterology & Hepatology, Aug 1, 2019
Take-down policy If you believe that this document breaches copyright please contact us providing... more Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.
Hpb, Apr 1, 2016
81.2% mild); jaundice was observed in 62 patients. Preoperative radiologic imaging was done in 43... more 81.2% mild); jaundice was observed in 62 patients. Preoperative radiologic imaging was done in 43 patients (CT scan in 7.1%, MRI in 31.3%). There were 70 transcystic and 42 transductal choledochoscopies with a median IQR operative time of 77.5 (110e65) vs. 122.5 (140e94) minutes, p < 0.001. T-tubes were placed only in 13 (11.5%) patients. Complete clearance of the bile duct was achieved in 91.1% leading to a conversion rate of 2.7%; in 6.2% of cases additional postoperative ERCP was performed. Readmission and ERCP for missed stones was needed in 3.6% of all cases. The overall postoperative complication rate reached 6.3%. The median IQR overall hospital stay was 9 (14e7) days. Conclusions: One-stage surgical approach is rational in the management of patients with a high risk of CBD stones.
Keighley & Williams’ Surgery of the Anus, Rectum and Colon, 2018
Nederlands tijdschrift voor geneeskunde, 2010
Haemorrhoids occur in approximately 30% of the population. Commonly occurring complaints include ... more Haemorrhoids occur in approximately 30% of the population. Commonly occurring complaints include blood loss, pruritus, hygiene problems and soiling. A high-fibre diet, with dietary-fiber supplementation if required, often resolves the symptoms. When symptoms are not resolved, the next step is rubber band ligation: a safe and easy procedure. In the long term, the result of rubber band ligation is often unsatisfactory. Haemorrhoidectomy was formerly the only alternative. Haemorrhoidectomy can be accompanied by serious complications, such as disabling pain and incontinence. Haemorrhoidectomy was therefore considered obsolete by the Dutch Institute for Healthcare Improvement (CBO) guideline of 1994. Today new operative procedures are available: Doppler-guided haemorrhoidal artery ligation (DG-HAL) and stapled anopexy. Both techniques are safe and yield good results. Moreover, these techniques cause little postoperative pain. DG-HAL and stapled anopexy offer an alternative for patients w...
The Netherlands journal of medicine, 2011
Surgical Endoscopy, 2012
Background Risk factors for conversion in cholecystectomy may be of clinical value. This study ai... more Background Risk factors for conversion in cholecystectomy may be of clinical value. This study aimed to investigate whether a set of risk factors, including the surgeon's specialization, can be used for the development of a preoperative strategy to optimize conversion outcome. Methods The data for all patients who underwent laparoscopic cholecystectomy at a single institution between January 2004 and December 2008 were retrospectively reviewed. Factors predictive for conversion were identified, and a preoperative strategy model was deduced. Results Of the 1,126 patients analyzed, 106 (9%) underwent laparoscopic cholecystectomy in an emergency setting. Delayed surgery was performed for 63 (46%) of 138 patients (12%) with acute cholecystitis. Preoperative endoscopic retrograde cholangiography was achieved for 161 of the patients (14%). Risk factors predictive of conversion (for 65 patients) were male gender [odds ratio (OR), 2.3; 95% confidence interval (CI), 1.3-3.9; p = 0.004], age older than 65 years (OR, 2.6; 95% CI, 1.4-4.8; p = 0.002), body mass index (BMI) exceeding 25 kg/m 2 (OR, 3.4; 95% CI, 1.7-7.1; p \ 0.001), history of complicated biliary disease (HCBD) (OR, 5.6; 95% CI, 3.2-9.8; p = \ 0.001), and surgery by a non-gastrointestinal (non-GI) surgeon (OR, 4.9; 95% CI, 2.2-10.6; p \ 0.001). The conversion rate for patients with a history of no complications who had two or more risk factors (gender, age, BMI [ 25) and for patients with a HCBD who had one or more risk factors was significantly higher if the surgery was performed by non-GI rather than GI surgeons. Conclusion Male gender, age older than 65 years, BMI exceeding 25 kg/m 2 , HCBD, and surgery by a non-GI surgeon are predictive for conversion. A preoperative triage for surgeon selection based on risk factors and a HCBD is proposed to optimize conversion outcome.
Radiology, 2007
To prospectively compare in a multicenter study the agreement between endoanal magnetic resonance... more To prospectively compare in a multicenter study the agreement between endoanal magnetic resonance (MR) imaging and endoanal ultrasonography (US) in depicting external anal sphincter (EAS) defects in patients with fecal incontinence. The study was approved by the medical ethics committee of all participating centers. A total of 237 consenting patients (214 women, 23 men; mean age, 58.6 years +/- 13 [standard deviation]) with fecal incontinence were examined from 13 different hospitals by using endoanal MR imaging and endoanal US. Patients with an anterior EAS defect depicted on endoanal MR images and/or endoanal US scans underwent anal sphincter repair. Surgical findings were used as the reference standard in the determination of anterior EAS defects. The Cohen kappa statistic and McNemar test were used to calculate agreement and differences between diagnostic techniques. Agreement between endoanal MR imaging and endoanal US was fair for the depiction of sphincter defects (kappa = 0.24 [95% confidence interval: 0.12, 0.36]). At surgery, EAS defects were found in 31 (86%) of 36 patients. There was no significant difference between MR imaging and US in the depiction of sphincter defects (P = .23). Sensitivity and positive predictive value were 81% and 89%, respectively, for endoanal MR imaging and 90% and 85%, respectively, for endoanal US. In the selection of patients for anal sphincter repair, both endoanal MR imaging and endoanal US are sensitive tools for preoperative assessment, and both techniques can be used to depict surgically repairable anterior EAS defects.
International Journal of Radiation Oncology*Biology*Physics, 2010
Biological, physical and clinical aspects of cancer treatment with ionising radiatio
European Journal of Gastroenterology & Hepatology, 2013
Digestive Surgery, 2009
Background/Aims: Procedures for haemorrhoidal prolapse that maintain functional haemorrhoidal ana... more Background/Aims: Procedures for haemorrhoidal prolapse that maintain functional haemorrhoidal anatomy are progressively used. The procedure for prolapse and haemorrhoids (PPH) has advantages over conventional haemorrhoidectomy, but is associated with a higher recurrence rate. The feasibility and efficiency of a second PPH instead of haemorrhoidectomy in case of recurrent symptoms were studied. Methods: A retrospective chart review was conducted of all patients that were treated with PPH for haemorrhoidal prolapse in our hospital between May 2002 and November 2008. All patients in need for a second PPH because of persistent or recurrent symptoms of prolapse were identified and analyzed. Results: Out of 137 patients who underwent a PPH, 22 patients (16%) were in need of a reoperation for symptoms of prolapse. Of these, 12 (55%) were treated with a second PPH. Successful prolapse reduction was achieved in 11 out of 12 patients. No postoperative complications were encountered during a m...
Colorectal Disease, 2012
Comparison of functional and surgical outcome of the J-pouch with the side-to-end coloanal anasto... more Comparison of functional and surgical outcome of the J-pouch with the side-to-end coloanal anastomosis after preoperative radiotherapy and total mesorectal excision in rectal cancer patients. In a multicentre study, patients with a carcinoma of the lower two-thirds of the rectum were randomized to either a J-pouch or a side-to-end reconstruction. Primary outcome was function of the neorectum 1 year after surgery. A functional outcome [COloREctal Functional Outcome (COREFO)] questionnaire, and two quality of life questionnaires (EORTC-QLQ-CR38 and SF-36) were to be completed by all participants preoperatively, and 4 and 12 months postoperatively. Independent data managers recorded surgical outcome. A group size of 30 patients in each group was calculated based on a 15-point difference of the COREFO scale. In total, 107 patients were randomized, 55 in the J-pouch group and 52 in the side-to-end anastomosis group. The COREFO incontinence scale at 4 months and the total functional outcome at 4 and 12 months showed better results for the J-pouch group in comparison with the side-to-end anastomosis group. The remaining COREFO scales (frequency, social impact, stool-related aspects and bowel medication), surgical outcome (complications, reoperations, length of hospital stay, readmissions and mortality) and quality of life did not show significant differences between treatment groups. The overall results of a coloanal J-pouch and a side-to-end anastomosis are comparable, although functional results are slightly better with a J-pouch. The side-to-end anastomosis is technically less demanding and therefore a justified alternative in sphincter-saving surgery.
Colorectal Disease, 2012
The procedure for prolapse and haemorrhoids (PPH) is an effective surgical therapy for symptomati... more The procedure for prolapse and haemorrhoids (PPH) is an effective surgical therapy for symptomatic haemorrhoids. Compared with haemorrhoidectomy, meta-analysis has shown PPH to be less painful, with higher patient satisfaction and a quicker return to work, but at the cost of higher prolapse recurrence rates. This is the first report describing predictors of prolapse recurrence after PPH. A cohort of patients with symptomatic haemorrhoids, treated with PPH in our hospital between 2002 and 2009, was retrospectively analysed. Multivariate analysis was performed to identify patient-related and perioperative predictors associated with persisting prolapse and prolapse recurrence. In total, 159 consecutively enrolled patients were analysed. Persistence and recurrence of prolapse was observed in 16% of the patients. Increased surgical experience showed a trend towards lower recurrence rates. Multivariate analysis identified female gender, long duration of PPH surgery and the absence of muscle tissue in the resected specimen as independent predictors of postoperative persistence of prolapse of haemorrhoids. The absence of prior treatment with rubber band ligation (RBL) as well as increased PPH experience at the hospital showed a trend towards a higher rate of prolapse recurrence. In order to reduce recurrence of prolapse, PPH should be performed by a surgeon with adequate PPH experience, patients should be treated with RBL prior to PPH and a resection of mucosa with underlying muscle fibres should be strived for.
Colorectal Disease, 2014
As a result of their extent and complexity, pelvic wounds after surgery for anorectal malignancy ... more As a result of their extent and complexity, pelvic wounds after surgery for anorectal malignancy often require a multidisciplinary approach to accomplish closure. This report describes a successful reconstruction using the lotus petal perforator flap. This flap is based on perforators of the internal pudendal artery and was partially depithelialized for plugging the defect. Wound healing was achieved after 12 days. The lotus petal flap is a relatively simple and successful choice for reconstruction of an extended chronic presacral defect after radiotherapy and rectal cancer resection.
Colorectal Disease, 2009
Continent ileostomy (CI) after proctocolectomy is an alternative technique compared to an ileal p... more Continent ileostomy (CI) after proctocolectomy is an alternative technique compared to an ileal pouch-anal anastomosis (IPAA). The question arises as to whether this technique is valuable. The aim of this study was to evaluate the role of the continent ileostomy, by patient follow-up satisfaction and quality of life assessment. Twenty-eight patients with a continent ileostomy operated between 1996 and 2007 were compared with patients who received an IPAA or a conventional ileostomy. SF-36 and EORTC QLC-CR38 questionnaires and a specific continent ileostomy questionnaire were used to assess differences and patient satisfaction. The quality of life in patients with a CI is not significant better or worse than patients with either a conventional ileostomy or an IPAA. On three scales (sexual enjoyment, gastro-intestinal tract symptoms and male sexual problems) statistically significant differences were reported. Overall, nearly all patients are very satisfied with the CI. All patients would make the same decision again and would recommend this procedure to other patients. The continent ileostomy remains to be a suitable alternative for the preservation of continence after a proctocolectomy, especially when an ileal pouch-anal anastomosis is not an option. If a choice has to be made between a CI and conventional ileostomy good preoperative counselling is necessary to make a well founded decision. To minimize complications, these procedures have to be performed in centres with specific expertise. Therefore, knowledge about the CI should be preserved for the future.
European Journal of Surgical Oncology
European Journal of Surgical Oncology
Dates of consent of participating centres.