Christoph A. Maurer
University of Basel
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Featured researches published by Christoph A. Maurer.
Annals of Surgery | 2001
Kaspar Z’graggen; Christoph A. Maurer; Stefan Birrer; Daniel Giachino; Beatrice Kern; Markus W. Büchler
ObjectiveTo analyze the feasibility, safety, complication and death rates, and early functional results of the transverse coloplasty pouch procedure after low anterior rectal resection and total mesorectal excision. Summary Background DataThe authors previously developed a novel neorectal reservoir, the transverse coloplasty pouch, in an animal model; they report the first clinical data of a prospective phase 1 study. MethodsForty-one patients underwent low anterior rectal resection with total mesorectal excision for rectal cancer (n = 37) or benign pathology (n = 4). The continuity was restored with a transverse coloplasty pouch anastomosis, and the colon was defunctionalized for 3 months. Patients were followed up at 2-month intervals for functional outcome. ResultsIntraoperative complications occurred in three patients (7%), none related to the transverse coloplasty pouch. There were no hospital deaths and the total complication rate was 27% (11/41); an anastomotic leakage rate of 7% was recorded. The stool frequency was 3.4 per 24 hours at 2 months follow-up and gradually decreased to 2.1 per 24 hours at 8 months. Stool dysfunctions such as stool urgency, fragmentation, and incontinence grade 1 and 2 were regularly observed until 6 months; the incidence significantly decreased thereafter. None of the patients had difficulties in pouch evacuation. ConclusionsThe transverse coloplasty pouch is a small-volume reservoir that can safely be used for reconstruction after sphincter-preserving rectal resection. The early functional outcome is favorable and can be compared to other colonic reservoirs. The concept of reducing early dysfunction seen after straight coloanal anastomosis and avoiding long-term problems of pouch evacuation is supported by this study. Future trials will compare the transverse coloplasty pouch with other techniques of restorative resections of the rectum.
Diseases of The Colon & Rectum | 2000
Christoph A. Maurer; Pietro Renzulli; Luca Mazzucchelli; Bernhard Egger; Christian Seiler; Markus W. Büchler
PURPOSE: Stercoral perforation of the colon is reported to be a rare disease with poor prognosis. The aim of this study was to determine the frequency of stercoral perforation of the colon, to define diagnostic criteria for stercoral perforation of the colon, and to analyze the patient outcome in a university hospital gastrointestinal surgery unit. METHODS: From November 1993 until November 1998 all surgically treated patients with a colorectal disease were prospectively recorded in a computerized database. Diagnosis of stercoral perforation of the colon was made if 1) the colonic perforation was round or ovoid, exceeded 1 cm in diameter, and lay antimesenteric; 2) fecalomas were present within the colon, protruding through the perforation site or lying within the abdominal cavity; and 3) pressure necrosis or ulcer and chronic inflammatory reaction around the perforation site were present microscopically. Any additional colon pathology led to exclusion from the diagnosis of stercoral perforation of the colon. Using the same criteria, 81 cases in the literature were found to qualify and were further analyzed. RESULTS: In a five-year period 1,295 patients underwent colorectal interventions through laparotomy. A total of 566 (44 percent) cases were emergencies, 220 (17 percent) of these caused by colonic perforation. Seven patients had stercoral perforation of the colon. The incidence of stercoral perforation of the colon was 0.5 percent of all surgical colorectal procedures through laparotomy, 1.2 percent of all emergency colorectal procedures, and 3.2 percent of all colonic perforations. The mean age of the patients was 59 (median, 64; range, 22–85) years. All perforations were situated in the left hemicolon or upper rectum. The round or ovoid perforation had a mean diameter of 3.6 cm. Fecalomas were present in all patients and protruded from the perforation site or were found within the free abdominal cavity in three of them. Generalized stercoral peritonitis was a constant finding. Using a colonic resection without immediate restoration of continuity, an extensive intraoperative lavage, and antibiotics, there was no in-hospital mortality. Analysis of the reports in the literature revealed additionally that 28 percent of patients with stercoral perforation of the colon have multiple stercoral ulcers in the colon and that substantial mortality is encountered if only minor surgical procedures of treatment are used. CONCLUSIONS: The incidence of stercoral perforation of the colon seemed to have been underestimated. The reason for this might be the lack of defined diagnostic criteria for this disease. Low mortality is obtained by early surgical eradication of the affected part of the colon, including all stercoral ulcers, and by aggressive therapy for peritonitis.
World Journal of Surgery | 2006
Sven Richter; Werner Lindemann; Otto Kollmar; Georg A. Pistorius; Christoph A. Maurer; Martin K. Schilling
IntroductionGuidelines for the treatment of complicated sigmoid diverticulitis recommend Hartmann’s procedure or anastomosis with protective colostomy for Hinchey stage III diverticulitis and Hartmann’s procedure only for Hinchey stage IV diverticulitis. We evaluated the outcome of patients with perforated sigmoid diverticulitis Hinchey III/IV undergoing one-stage colon resection and primary anastomosis without protective colostomy.MethodsAfter implementation of a protocol to treat Hinchey III/IV diverticulitis with primary anastomosis without protective ileocolostomy, the patients’ data were recorded prospectively between August 2001 and August 2003 and analyzed retrospectively from a computer-related database.ResultsOf 41 patients, 34 (81%%) underwent one-stage sigmoid resection and primary anastomosis, 3 of 41 patients (7%%) underwent primary anatomosis with protective ileostomy, and 5 of 41 patients (12%%) had a Hartmann’s procedure. The mortality was 11%% in patients undergoing primary anastomosis and 60%% in patients with Hartmann’s procedure. The relative risk of co-morbidity factors for lethal outcome after sigmoid resection was 6.94 for preceding operations, 3.75 for renal failure or renal transplantation, and 3.25 for immunosuppression.ConclusionsOne-stage sigmoid resection and primary anastomosis can be performed safely in nearly 90%% of all patients with perforated sigmoid diverticulitis (Hinchey III/IV) by surgeons of different training levels. Patients with immunosuppression, chronic renal failure, liver cirrhosis, or previous organ transplantation or complex cardiovascular reconstructive procedures have a significantly increased risk of dying after sigmoid resection for perforated diverticulitis.
Digestive Diseases and Sciences | 1998
Christoph A. Maurer; Helmut Friess; Sabine S. Buhler; Beatrice R. Wahl; Hans U. Graber; Arthur Zimmermann; Markus W. Büchler
Since the role of the Bcl-2 gene family has beenonly poorly investigated in colorectal cancer, we haveexamined the expression of the apoptosis blockersBcl-xL and Bcl-2, as well as the proapoptoticfactors Bax and Bak. Northern blot analysis andimmunohistochemistry were performed on normal andcancerous colonic tissue from 12 patients. In colorectalcancer, Bcl-xL immunoreaction was strongerthan in normal controls, and 83% of the cancers had increasedBcl-xL mRNA expression. The mediandensitometric Bcl-xL values were 3.4-foldhigher in carcinomas (P < 0.005). In contrast to thenormal colon, colorectal carcinomas often lack any Bcl-2 immunostaining,and Bcl-2 mRNA was not detectable by Northern blotseither. Bax was not obviously altered in colorectalcancer, either at the protein level or at the mRNA level compared to the normal control colon. BakmRNA expression exhibited a wide variation incarcinomas, but was somewhat decreased in comparison tothe controls. Of these members of the Bcl-2 gene family, Bcl-xL seems to play a major role incolorectal tumori genesis and disease progression. Anagonistic effect might have caused the tendency forreduced Bak expression. The Bcl-2/Bax regulation systemof cell homeostasis seems to be of lesserimportance.
Archives of Surgery | 2009
Matthias Echternach; Christoph A. Maurer; Thomas Mencke; Martin K. Schilling; Thomas Verse; Bernhard Richter
HYPOTHESIS Laryngeal dysfunction after thyroidectomy is a common complication. However, few data are available to differentiate whether these complications result from injury to the recurrent nerve or to the vocal folds from intubation. SETTING University medical center. PATIENTS Seven hundred sixty-one patients who underwent surgery to the thyroid gland from 1990 to 2002. Of these patients, 8.4% underwent a revision thyroidectomy. INTERVENTION Preoperative and postoperative laryngostroboscopic examination. MAIN OUTCOME MEASURE Laryngostroboscopic evaluation of laryngeal complications. RESULTS The overall rate of laryngeal complications was 42.0% (320 patients). Complications from an injury to the vocal folds occurred in 31.3% of patients. Weakness or paresis of the recurrent nerve was initially present in 6.6% and was related to the nerves at risk. This rate was higher in revision thyroidectomies than in primary surgical interventions (6.2% vs 11.6%; P = .04). The rate of laryngeal injuries was higher in patients older than 65 years (39.8% vs 30.8%; P = .03). CONCLUSIONS These data suggest that laryngeal complications after thyroidectomies are primarily caused by injury to the vocal folds from intubation and to a lesser extent by injury to the laryngeal nerve. We recommend documentation of informed consent, especially for patients who use their voice professionally, such as singers, actors, or teachers.
Digestive Surgery | 2002
Pietro Renzulli; Christoph A. Maurer; Peter Netzer; Markus W. Büchler
Aims: Analysis of preoperative and operative management of acute colonic volvulus and development of treatment guidelines in a region of low incidence. Methods: A study of 42 consecutive patients operated for acute colonic volvulus between 1970 and 2000. Results: There were 20 patients with sigmoid volvulus, 21 with cecal volvulus and 1 with volvulus of the transverse colon. All patients presented as emergencies. The correct preoperative diagnosis was possible for sigmoid volvulus in 95% (19/20) of cases and for cecal volvulus in 67% (14/21). Preoperative colonoscopic volvulus derotation was attempted in 19 patients and successfully completed in 9 patients (47%). The success rates for preoperative colonoscopic derotation were 58 (7/12) and 33% (2/6) for sigmoid and cecal volvulus, respectively. Thirty-four patients (81%) underwent colon resections, 26 times as a single-stage procedure, and 8 patients (19%) underwent non-resectional operative techniques. Overall surgical morbidity was 24%, the reoperation rate 9.5% and mortality 12% (5/42). The subgroup of 9 patients with successful non-operative volvulus derotation, however, underwent semi-elective single-stage colonic resection without surgical morbidity or mortality. There were no recurrences during a median follow-up period of 9.5 years. Conclusion: In the absence of clinical, laboratory or radiological signs of bowel necrosis or perforation, colonoscopic volvulus derotation is recommended in all cases of acute colonic volvulus, followed by semi-elective single-stage colonic resection.
World Journal of Hepatology | 2011
Beat M. Künzli; Paolo Abitabile; Christoph A. Maurer
Over the past decade, radiofrequency ablation (RFA) has evolved into an important therapeutical tool for the treatment of non resectable primary and secondary liver tumors. The clinical benefit of RFA is represented in several clinical studies. They underline the safety and feasibility of this new and modern concept in treating liver tumors. RFA has proven its clinical impact not only in hepatocellular carcinoma (HCC) but also in metastatic disease such as colorectal cancer (CRC). Due to the increasing number of HCC and CRC, RFA might play an even more important role in the future. Therefore, the refinement of RFA technology is as important as the evaluation of data of prospective randomized trials that will help define guidelines for good clinical practice in RFA application in the future. The combination of hepatic resection and RFA extends the feasibility of open surgical procedures in patients with extensive tumors. Adverse effects of RFA such as biliary tract damage, liver failure and local recurrence remain an important task today but overall the long term results of RFA application in treating liver tumors are promising. Incomplete ablation of liver tumors due to insufficient technology of ablation needles, tissue cooling by the neighbouring blood vessels, large tumor masses and ablation of tumors in close vicinity to heat sensitive organs remain difficult tasks for RFA. Future solutions to overcome these limitations of RFA will include refinement of ultrasonographic guidance (accuracy of probe placement), improvements in needle technology (e.g. needles preventing charring) and intraductal cooling techniques.
Digestive Surgery | 2000
Jan Heidemann; Martin K. Schilling; Adrian Schmassmann; Christoph A. Maurer; Markus W. Büchler
Background: With the advent of stage-adapted multimodal regimens for many gastrointestinal malignancies, accurate staging has become of utmost importance. In esophageal cancer, endoscopic ultrasonography (EUS) emerged as standard to determine T and N stage. Objective: Since growth patterns of squamous carcinoma (SC) differs from adenocarcinoma (AC) and lymph nodes are located at various distances from the esophagus in a horizontal plane, we studied the accuracy of esophageal EUS as a function of tumor type and localization of the tumor within the esophagus. Results: Overall staging accuracy was 79% for T and for N staging. Staging was more accurate for T3/4, when compared to T1/2 tumors, and for SC when compared to AC. Histological T1/2 stages were overstaged by EUS in 8/17 patients, mostly in patients with AC (6/10). The sensitivity of retrosternal pain and of dysphagia for extramural disease was 57 and 92% respectively, the specificity of pain for extramural disease was 73%, and of dysphagia 36%. Preoperative weight loss in this series correlated linearly with tumor stages. Conclusions: The accurate preoperative staging of T2 esophageal endodermal malignancies is crucial for treatment stratification but difficult to achieve by visual analysis of endosonography alone. Postacquisition processing of echoendosonographic images might further increase the accuracy of echoendosonography and aid in the critical differentiation of T2 versus T3 esophageal malignancies. Preoperative weight loss and retrosternal pain are good clinical indicators of extramural disease.
Scandinavian Journal of Gastroenterology | 2010
Samuel A. Käser; Gerhard Fankhauser; Niels Willi; Christoph A. Maurer
Abstract Objective. Very recently it has been shown that hyperbilirubinemia is a specific predictor of perforation in acute appendicitis. We compared the diagnostic importance of bilirubin, C-reactive protein (CRP), leukocyte count and age as markers of perforation in acute appendicitis. Material and methods. A two-center retrospective cohort study was completed. Patients with acute appendicitis (n = 725) were divided into two groups, group A with perforation (n = 155) and group B without (n = 570). Results. In group A an elevated CRP (> 5 mg/l) was measured in 98% of cases versus 72.5% in group B. Hyperbilirubinemia (> 20 μmol/l) was measured in 38% of cases in group A versus 22.3% in group B. Leukocytosis (> 10 × 109/l) was measured in 85% of cases in group A versus 79.3% in group B. Analysis of qualitative and quantitative data showed every marker to be significantly correlated with perforation except elevated white cell blood count. However CRP showed the strongest correlation. The logistic regression model showed CRP to be by far the most significant marker of perforation. Conclusions. Our results confirm hyperbilirubinemia to be a statistically significant marker of perforation in acute appendicitis. However, CRP is superior to bilirubin for anticipation of perforation in acute appendicitis.
The American Journal of Surgical Pathology | 2002
Nicolas Leupin; Jürgen Curschmann; Helmut Kranzbühler; Christoph A. Maurer; Jean A. Laissue; Luca Mazzucchelli
The histopathologic features of acute radiation-induced colitis in humans have been described in occasional, >20-year-old studies, but they have not been analyzed in detail. We characterize such findings in 34 patients with rectal cancer who underwent surgery a few days after preoperative irradiation with 25 Gy given over 5–7 days, and we compare the results to the histopathologic features detected in 18 patients treated by a conventional preoperative irradiation protocol consisting of 45 Gy during 5 weeks followed by surgery after a time interval of at least 3 weeks. Short-term preoperative irradiation therapy generally induced severe mucosal inflammation characterized by increased cellularity of the lamina propria, prominent eosinophilic infiltrates, crypt disarray, surface and crypt epithelial damage, nuclear abnormalities, and presence of apoptotic bodies in the crypt epithelium. These histopathologic features were absent or detected only occasionally in the patient group treated according to the long-term preoperative irradiation protocol. Despite acute severe inflammation, none of the patients treated by short-term irradiation developed perioperative complications. These observations indicate that acute radiation colitis may remain clinically silent and resolve spontaneously within a few weeks after irradiation. Given the widening acceptance of short-term preoperative irradiation protocols for rectal cancer, pathologists should be aware of the rather characteristic histologic findings of acute radiation colitis and avoid unnecessary concern of clinicians. The differential diagnosis includes infectious colitis, collagenous and ischemic colitis, nonsteroidal anti-inflammatory drug-associated colitis, and chronic idiopathic inflammatory bowel disease.