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PubMed2001

Human glandular kallikrein 2 levels in serum for discrimination of pathologically organ-confined from locally-advanced prostate cancer in total PSA-levels below 10 ng/ml.

BACKGROUND: We measured serum levels of human glandular kallikrein 2 (hK2) in patients treated with radical retropubic prostatectomy (rrP) for clinically localized prostate cancer (PCa) with a total PSA (tPSA)-level below 10 ng/ml to investigate whether hK2 can be applied to preoperatively distinguish organ-confined (pT2a/b) from nonorgan-confined (> or = pT3a)-PCa more accurately than total PSA. Further, we evaluated hK2, free- and tPSA-concentrations in all pathologic stages of PCa. METHODS: 161 serum samples from men scheduled for rrP were collected 1 day before surgery prior to any prostatic manipulation. Pathologic work-up revealed > or = pT3a-PCa in 48 and pT2a/b-PCa in 113 patients. HK2-levels in serum were measured using an immunofluorometric assay with an analytical sensitivity of 0.5 pg/ml, a functional sensitivity of 5 pg/ml and insignificant cross-reactivity with PSA (< 0.005%). Total (tPSA) and free PSA (fPSA) levels were measured using a commercially available assay from which we calculated %fPSA and an algorithm that combined hK2 and PSA-levels [hK2] x [tPSA/fPSA]. Means, medians, and ranges were calculated for pT2a/b vs. >/= pT3a-PCa and for all pathologic stages. Statistical significance of differences was calculated using Mann-Whitney-U and Kruskal-Wallis tests. Calculation of receiver-operator-characteristic (ROC) curves were performed for hK2, [hK2] x [tPSA/fPSA] and tPSA to compare diagnostic performance. RESULTS: A mean tPSA level in serum of 6.12 ng/ml in > or = pT3a-PCa was not significantly different (P = 0.366) from 5.78 ng/ml in pT2a/b-PCa. Also, there were no statistically significantly different levels of fPSA (P = 0.947) or %fPSA (0.292) for these two groups. By contrast, mean hK2-level in pT2a/b-PCa of 80 pg/ml was significantly different (P = 0.004) from a mean hK2 level of 120 pg/ml in > or = pT3a-PCa as shown by Mann-Whitney-analysis Moreover, the algorithm of [hK2] x [tPSA/fPSA] was significantly lower (P = 0.0004) in pT2a/b-PCa vs. > or = pT3a-PCa. Calculation of areas under curve (AUC) by receiver-operator-characteristics (ROC) demonstrated that the AUC for hK2 (0.64) was larger and the AUC for [hK2] x [tPSA/fPSA] (=0.68) significantly larger (P = 0.007) compared to the AUC of tPSA (0.55). Furthermore, Kruskal-Wallis Test revealed a highly significant correlation to pathologic stage using hK2 (P = 0.008) and [hK2] x [tPSA/fPSA] (P = 0.0015) compared to no significant differences in serum concentration of tPSA (P = 0.296). Also at tPSA-levels from 10-20 ng/ml, the hK2-levels in pT2a/b-PCa were close to significantly different (P = 0.051) from those in men with >/= pT3a-PCa, while the algorithm of [hK2] x [tPSA/fPSA] in that tPSA-range was significantly lower (P = 0.002) in pT2a/b-PCa compared to > or = pT3a0-PCa. CONCLUSIONS: Highly significant differences in serum concentration enable hK2 to be a powerful predictor of organ-confined disease and pathologic stage of clinically localized prostate cancer, especially in the PSA-range below 10 ng/ml. As such, there are important clinical consequences for the application of hK2 for the adequate treatment of prostate cancer patients, i.e., the option of nerve-sparing surgery. (c) 2001 Wiley-Liss, Inc.

Area Under Curve↗
PubMed2003

Procalcitonin serum levels after out-of-hospital cardiac arrest.

The time course of Procalcitonin (PCT) serum levels was assessed in cardiac arrest survivors and compared with S-100 serum levels concerning their predictive values for neurological outcome. PCT and S-100 serum levels were analyzed serially on admission and during the following 3 days after hospitalization in 23 patients successfully resuscitated from out-of-hospital cardiac arrest. At day 14 patients were divided into groups according to the Glasgow-Outcome-Scale (GOS): one group with bad neurological outcome (GOS 1-3) and one group with good neurological outcome (GOS 4-5). Group comparisons were performed with the Mann-Whitney U-Test. The diagnostic performance of PCT and S-100 levels was analyzed using receiver operating characteristics (ROC). Patients with a bad neurological outcome had significantly higher S-100 levels than those with a good neurological outcome at all investigated time points and significantly elevated PCT levels at days 1-3. Highest levels for S-100 were found immediately after hospitalization (3.4 +/- 3.8 vs. 0.7 +/- 0.3 microg/l, P=0.003), and for PCT at day 1 (37 +/- 103 vs. 0.2 +/- 0.2 microg/l, P=0.0002). The results show that PCT serum levels are possibly elevated in patients with bad neurological outcome after cardiac arrest, without signs of severe infection or concomitant sepsis. Based on this observation, studies on larger numbers of patients should prove the predictive value of PCT in those patients.

After-Hours Care↗
PubMed2002

Computer-aided diagnosis of breast tumors with different US systems.

RATIONALE AND OBJECTIVES: The authors performed this study to determine whether a computer-aided diagnostic (CAD) system was suitable from one ultrasound (US) unit to another after parameters were adjusted by using intelligent selection algorithms. MATERIALS AND METHODS: The authors used texture analysis and data mining with a decision tree model to classify breast tumors with different US systems. The databases of training cases from one unit and testing cases from another were collected from different countries. Regions of interest on US scans and co-variance texture parameters were used in the diagnosis system. Proposed adjustment schemes for different US systems were used to transform the information needed for a differential diagnosis. RESULTS: Comparison of the diagnostic system with and without adjustment, respectively, yielded the following results: accuracy, 89.9% and 82.2%; sensitivity, 94.6% and 92.2%; specificity, 85.4% and 72.3%; positive predictive value, 86.5% and 76.8%; and negative predictive value, 94.1% and 90.4%. The improvement in accuracy, specificity, and positive predictive value was statistically significant. Diagnostic performance was improved after the adjustment. CONCLUSION: After parameters were adjusted by using intelligent selection algorithms, the performance of the proposed CAD system was better both with the same and with different systems. Different resolutions, different setting conditions, and different scanner ages are no longer obstacles to the application of such a CAD system.

Algorithms↗
PubMed2004

Accuracy of computed tomographic angiography and magnetic resonance angiography for diagnosing renal artery stenosis.

BACKGROUND: Timely, accurate detection of renal artery stenosis is important because this disorder may be a potentially curable cause of hypertension and renal impairment. OBJECTIVE: To determine the validity of computed tomographic angiography (CTA) and magnetic resonance angiography (MRA) compared with digital subtraction angiography (DSA) for detection of renal artery stenosis. DESIGN: Prospective multicenter comparative study conducted from 1998 to 2001. Two panels of 3 observers judged CTA and MRA image data and were blinded to all other results. Digital subtraction angiography images were evaluated by consensus. SETTING: 3 large teaching hospitals and 3 university hospitals in the Netherlands. PATIENTS: 402 hypertensive patients with suspected renal artery stenosis were included. A group of 356 patients who underwent all 3 diagnostic tests was used for analysis. MEASUREMENTS: Reproducibility was assessed by calculating interobserver agreement. Diagnostic performance was evaluated in terms of sensitivity, specificity, and other diagnostic variables. Atherosclerotic stenoses of 50% or greater and fibromuscular dysplasia were considered clinically relevant. RESULTS: Twenty percent of patients who underwent all 3 tests had clinically relevant renal artery stenosis. Moderate interobserver agreement was found, with kappa values ranging from 0.59 to 0.64 for CTA and 0.40 to 0.51 for MRA. The combined sensitivity and specificity were 64% (95% CI, 55% to 73%) and 92% (CI, 90% to 95%) for CTA and 62% (CI, 54% to 71%) and 84% (CI, 81% to 87%) for MRA. LIMITATIONS: Eighteen percent of the patients were included nonconsecutively. Digital subtraction angiography may be an imperfect reference test. CONCLUSION: Computed tomographic angiography and MRA are not reproducible or sensitive enough to rule out renal artery stenosis in hypertensive patients. Therefore, DSA remains the diagnostic method of choice. *For a list of the other investigators and research coordinators who participated in RADISH, see the Appendix.

Adult↗
PubMedDate not supplied

Role of myocardial gated SPECT scintigraphy in the clinical suspicion of ischemic cardiomyopathy: discussion of an unusual case.

The case of a 72-year-old patient affected by myasthenia gravis under pyridostigmine therapy, admitted to the hospital for the onset of oppressive thoracic pain associated with mild enzyme increase, electrocardiographic and echocardiographic disorders, is discussed. Dypiridamole/gated SPECT perfusion scintigraphy at rest evidenced reduced coronary reserve at the level of the lateral wall with apical akinesia and normokinesia of mediobasal left ventricle. On coronarography, coronary arteries were free of significant stenoses and left ventricular apical akinesia. The diagnostic approach to ischemic cardiomyopathy with the correct sequence of performed diagnostic imaging led to the presumptive identification of a rare syndrome.

Aged↗
PubMed1993

A new method to assess the difficulty of a medical diagnosis: application to electrocardiographic interpretation.

A new method to assess the relative difficulty of a medical diagnosis and the efficacy of a diagnostic procedure is described. The cases within a population are classified by N independent interpreters, i.e., medical experts or computer programs. The percentages of correctly diagnosed cases by N (unanimity), N-1, N-2, ..., zero interpreters, respectively, are calculated. These N + 1 percentages are presented in a histogram. A cumulative plot is derived from the "unanimity" value. The ratio "unanimity value"/"zero value" is proposed as an index of diagnostic performance. An application to the CSE database is presented which is composed of 1,220 electrocardiographic tracings interpreted by 13 cardiologists and 15 computer programs. The cumulative plots, the performance index and Log (index) values, established for eight different diagnostic statements, clearly show the relative degree of diagnostic difficulty for each of them and the particular efficacy of each approach, i.e., electrocardiography versus vectorcardiography, and computerized versus human interpretation.

Diagnosis↗
PubMed1997

[The role of diagnostic laparoscopy in treatment of penetrating injuries of the lower thoracic wall and anterior abdominal wall].

Penetrating injuries of the lower thoracic wall and anterior abdominal wall cause difficulties in the decision for laparotomy. For gunshot wounds laparotomy without further investigations is in most cases justified, but in other penetrating traumata one should use every diagnostic modality to prevent unacceptably high negative laparotomy rates. We performed diagnostic laparoscopy (DL) on 39 patients with penetrating injuries of the anterior abdominal wall and/or lower thoracic wall. Of these 39 patients, 25 had negative and 14 positive results. We had only one false-negative finding. No false-positive result occurred. We think that DL is a very reliable diagnostic tool which requires a relatively high technology.

Abdominal Injuries↗
PubMed2002

Diagnostic implications of circulating oxidized low density lipoprotein levels as a biochemical risk marker of coronary artery disease.

OBJECTIVES: To examine the diagnostic performance of circulating oxidized low density lipoprotein levels as a biochemical risk marker of coronary heart disease. DESIGN AND METHODS: 361 patients with coronary artery disease and 710 healthy volunteers as normal controls were examined. Receiver-operating characteristics curve analysis in addition to statistical analysis (univariate, multivariate) were done to determine the usefulness of the assay. RESULTS: Patients with coronary artery disease showed significantly elevated circulating oxidized low density lipoprotein levels. Males less than 70 years of age showed a significant association between oxidized low density lipoprotein levels and coronary artery disease. Receiver-operating characteristics curve analysis showed superior performance (e.g., sensitivity, specificity) of oxidized low density lipoprotein as a diagnostic marker of coronary artery disease as compared against other lipid markers (total cholesterol, triglyceride, high density lipoprotein, lipoprotein (a), and total cholesterol to high density lipoprotein ratio) with optimal performance in younger males. CONCLUSIONS: Oxidized low density lipoprotein levels may be a promising biochemical risk marker of atherosclerotic disease, especially in young males.

Adult↗
PubMed1991

A performance evaluation of the expert system 'Jaundice' in comparison with that of three hepatologists.

The diagnostic performance of an Expert System (Jaundice) designed to discriminate between different causes of jaundice was evaluated in a test sample of 200 consecutive in-patients with serum bilirubin greater than or equal to 51 mumol/l. The average probability assigned to true diagnosis, the non-error rate and the overall accuracy were, respectively, 55%, 77% and 70%. The Expert System's discriminatory ability in probabilistic prediction, assessed by a method based on continuous functions of the diagnostic probabilities (Brier score) was good. We also compared the ability of our Expert System to that of three experienced hepatologists, who were required to give a diagnosis in 20 cases following the same protocol used by computer (i.e., by asking only clinical and laboratory items). Both the hepatologists and Jaundice achieved a correct diagnosis in 70% of 20 cases, but the Expert System asked a significantly higher average number of questions during each consultation. Analysis of the reasoning pathway made by an external referee showed a high agreement between the diagnostic strategies of the Expert System and the physicians. We conclude that Jaundice can be a useful tool to support a physician with insufficient clinical experience in this field to generate correct diagnostic hypotheses.

Diagnosis, Computer-Assisted↗
PubMed2007

[Validated diagnostics for dysgrammatism].

BACKGROUND: Non-standardized procedures are used to evaluate, in particular, grammatical performance in most German institutions performing diagnostic procedures on children with impaired speech and language development. This makes a comparison of results difficult. METHODS: We studied 181 boys and 72 girls aged between 5 and 6 years using four subtests of IDIS additionally to the routine procedure. Results were compared to the "degree of dysgrammatism" determined from the traditional evaluation based on expert rating. RESULTS: The new procedure is able to divide the children into groups with normal speech and language ability, with deficits accessible to a traditional logopedic treatment, and with severe speech and language impairment that necessitates intensive treatment. DISCUSSION: The proposed tests allow an accurate evaluation of grammatical performance instead of subjective estimates.

Articulation Disorders↗
PubMed2004

Multidetector CT enteroclysis: comparison of the reading performance for axial and coronal views.

The purpose of this study was to compare the diagnostic performance of axial and coronal views in multidetector CT enteroclysis (MDCTE). We retrospectively evaluated 48 patients with pathological correlation investigated by MDCTE for small bowel disorders. After nasojejunal administration of 2 l of 5% methylcellulose axial arterial and venous acquisition of MDCTE was followed by coronal reconstructions using equal slice thicknesses of 2.5 mm with 2 mm increments. Spatial resolution of both planes was evaluated by phantom. Three radiologists independently read axial and coronal images concerning 12 pathological features. The interobserver agreement and time of reading was calculated. Sensitivity and specificity resulted from comparison with histopathology (n=39) or follow-up (n=9). Phantom study revealed higher spatial resolution for axial than coronal views, whatever reconstruction interval was used. However, spatial frequency always remained high. Most pathological signs, such as bowel wall thickening (BWT), bowel wall enhancement (BWE) and intraperitoneal fluid (IPF), showed better interobserver agreement on axial than coronal views (BWT: 0.61 vs. 0.44; BWE: 0.56 vs. 0.5; IPF:0.53 vs. 0.43). The Wilcoxon signed-rank test revealed significantly higher sensitivity for axial than coronal views (P=0.0453); the time of reading was significantly shorter for the latter (P=0.0146). The diagnostic value of axial slices is superior to coronal reconstructions despite the reduced data volume and display of the physiological course of bowel loops on the coronal plane.

Adult↗
PubMed1992

Early diagnosis of acute myocardial infarction by a newly developed rapid immunoturbidimetric assay for myoglobin.

OBJECTIVE: To evaluate a rapid immunoturbidimetric assay for myoglobin and to investigate its clinical usefulness in the early detection of acute myocardial infarction. DESIGN: Prospective study. Immunoturbidimetrically determined myoglobin concentrations were compared with radioimmunoassay results obtained with the same blood samples. The diagnostic performance of myoglobin determination was compared with creatine kinase and creatine kinase MB activity (current standard of routine diagnosis). SETTINGS: Part 1: coronary care unit. Part 2: emergency room in a university hospital. PATIENTS: Part 1:30 patients with acute myocardial infarction admitted not later than four hours (median two hours) after the onset of symptoms. Part 2: 126 patients admitted to the emergency room with chest pain not caused by trauma (51 cases of acute myocardial infarction, 51 cases of angina pectoris, and 24 cases of chest pain not related to coronary artery disease). INTERVENTIONS: Part 1: routine treatment including intravenous thrombolytic treatment (28 patients). Part 2: routine emergency treatment without thrombolytic treatment. MAIN OUTCOME MEASURES: The analytical quality of the immunoturbidimetric myoglobin assay and a comparison between the myoglobin assay and creatine kinase and creatine kinase MB for diagnostic sensitivity and performance. RESULTS: The immunoturbidimetric myoglobin assay was fast and convenient and gave myoglobin determinations of high analytical quality. The concentration of myoglobin increased, peaked, and returned to the reference range significantly earlier than creatine kinase (p < or = 0.0001) and creatine kinase MB (p < or = 0.0002). Before thrombolytic therapy was started the diagnostic sensitivity of myoglobin was significantly higher than that of creatine kinase MB activity 0-6 h after the onset of chest pain and significantly higher (0.82 v 0.29) than creatine kinase 2-4 h after the onset of chest pain. In almost all patients (92%) plasma myoglobin concentrations were increased 4-6 h after the onset of chest pain. CONCLUSION: Myoglobin was more sensitive in detecting early myocardial infarction than creatine kinase and creatine kinase MB activity. Immunoturbidimetric myoglobin measurements could be useful in the early evaluation of patients with suspected myocardial infarction because this assay takes less than two minutes.

Clinical Enzyme Tests↗
PubMed1995

Digitized radiographs in skeletal trauma: a performance comparison between a digital workstation and the original film images.

PURPOSE: To evaluate the diagnostic performance of a teleradiology system in skeletal trauma. MATERIALS AND METHODS: Radiographs from 180 skeletal trauma patients were digitized (matrix, 2,000 x 2,500) and transmitted to a remote digital viewing console (1,200-line monitor). Four radiologists interpreted both the original film images and digital images. Each reader was asked to identify, locate, and characterize fractures and dislocations. Receiver operating characteristic curves were generated, and the results of the original and digitized film readings were compared. RESULTS: All readers performed better with the original film when interpreting fractures. Although the patterns varied between readers, all had statistically significant differences (P < .01) for the two image types. There was no statistically significant difference in performance with the two images when dislocations were diagnosed. CONCLUSION: The system tested is not a satisfactory alternative to the original radiograph for routine reading of fracture films.

Computer Communication Networks↗
PubMed1984

Investigating the efficacy of current quality assurance performance tests in diagnostic ultrasound.

The efficacy of four current quality assurance performance tests in diagnostic ultrasound was investigated. This was done by comparing the ability of the performance tests to detect fluctuations in gray scale, depth of penetration, axial resolution and lateral resolution on a real-time scanner with the ability of sonologists and sonographers to detect the same fluctuations. The performance tests for gray scale, depth of penetration, and axial resolution were found to be efficacious. The lateral resolution test was judged nonefficacious . This suggested a need to revise the protocol for the lateral resolution test with regard to real-time scanners.

Evaluation Studies as Topic↗
PubMed1977

Rationale for seeking occult metastases in patients with bronchial carcinoma.

The usefulness of performing diagnostic staging tests on patients thought to have operable bronchial carcinoma was explored by modeling the diagnostic and therapeutic processes for patients with this disease. The availability of appropriate autopsy and survival data allowed this investigation. We analyzed the results of two diagnostic and therapeeutic strategies: a test strategy in which extensive staging tests are performed preoperatively on patients with Stage I or II disease and a no test strategy in which such examinations are not performed. Average survival times are little affected by the choice of the test or no test diagnostic strategy. The chance of an immediate postoperative death, of an unnecessary operation and of a long term cure are affected more. Within the error of measurement, financial costs for the two strategies are probably the same. This investigation is a prototype for estimating the value of diagnostic staging tests and the effects of consequent alternative methods of treatment for patients with known malignant conditions.

Bronchial Neoplasms↗
PubMed2003

A multiple classifier system for early melanoma diagnosis.

Melanoma is the most dangerous skin cancer and early diagnosis is the key factor in its successful treatment. Well-trained dermatologists reach a diagnosis via visual inspection, and reach sensitivity and specificity levels of about 80%. Several computerised diagnostic systems were reported in the literature using different classification algorithms. In this paper, we will illustrate a novel approach by which a suitable combination of different classifiers is used in order to improve the diagnostic performances of single classifiers. We used three different kinds of classifiers, namely linear discriminant analysis (LDA), k-nearest neighbour (k-NN) and a decision tree, the inputs of which are 38 geometric and colorimetric features automatically extracted from digital images of skin lesions. Multiple classifiers were generated by combining the diagnostic outputs of single classifiers with appropriate voting schemata. This approach was evaluated on a set of 152 digital skin images. We compared the performances of multiple classifiers (2- and 3-classifier groups) between them and with respect to single ones (1-classifier group). We further compared the classifiers' performances with those of eight dermatologists. Classifiers' performances were measured in terms of distance from the ideal classifier. Compared with 1- and 2-classifier groups, performances of 3-classifier systems were significantly higher (P<0.0005 and P<0.001, respectively). No statistically significant differences were found between the 1- and 2-classifier groups (P=0.352). While the dermatologists group showed a level of performances significantly higher than the 1-classifier systems (P<0.020), no differences were found between the multiple classifier groups and the dermatologists groups, indicating comparable performances. This work suggests that a suitable combination of different kinds of classifiers can improve the performances of an automatic diagnostic system.

Algorithms↗
PubMed1997

Effect of ST segment measurement point on performance of exercise ECG analysis.

To evaluate the effect of ST-segment measurement point on diagnostic performance of the ST-segment/heart rate (ST/HR) hysteresis, the ST/HR index, and the end-exercise ST-segment depression in the detection of coronary artery disease, we analysed the exercise electrocardiograms of 347 patients using ST-segment depression measured at 0, 20, 40, 60 and 80 ms after the J-point. Of these patients, 127 had and 13 had no significant coronary artery disease according to angiography, 18 had no myocardial perfusion defect according to technetium-99m sestamibi single-photon emission computed tomography, and 189 were clinically 'normal' having low likelihood of coronary artery disease. Comparison of areas under the receiver operating characteristic curves showed that the discriminative capacity of the above diagnostic variables improved systematically up to the ST-segment measurement point of 60 ms after the J-point. As compared to analysis at the J-point (0 ms), the areas based on the 60-ms point were 89 vs. 84% (p=0.0001) for the ST/HR hysteresis, 83 vs. 76% (p<0.0001) for the ST/HR index, and 76 vs. 61% (p<0.0001) for the end-exercise ST depression. These findings suggest that the ST-segment measurement at 60 ms after the J-point is the most reasonable point of choice in terms of discriminative capacity of both the simple and the heart rate-adjusted indices of ST depression. Moreover, the ST/HR hysteresis had the best discriminative capacity independently of the ST-segment measurement point, the observation thus giving further support to clinical utility of this new method in the detection of coronary artery disease.

Coronary Disease↗
PubMed1998

How well can surgeons perform colonoscopy?

BACKGROUND: Little recent data exist relative to the efficacy or postprocedural complications of surgeons performing diagnostic or therapeutic colonoscopy. Therefore, the aim of this study was to retrospectively assess the outcome of colonoscopy performed by surgeons. METHODS: The charts of 2,069 patients who underwent colonoscopy between January 1992 and April 1995 by one of four surgeons at one of two centers were reviewed. Parameters included demographics, indications, procedures and findings, pathology, major complications, length of procedures and dosage of medication. RESULTS: 2,069 colonoscopies were performed for the following indications: 877 polyp surveillance, 509 cancer surveillance, 287 rectal bleeding, 282 family history of colon cancer, 127 change in bowel habits, 112 polyps found by flexible sigmoidoscope or barium enema, 92 inflammatory bowel disease, 48 preoperation, and 58 other indications. Some patients had more than one indication. The cecum could not be intubated in 73 cases (3.5%) due to narrowing and stricture [33] redundancy [18], poor preparation [14], and other miscellaneous conditions [8]. The average procedure time in the 1, 023 cases in which it was measured was 34.7 min. Average sedation doses were 2.1 mg of midazolam and 75.2 mg of meperedine in these same cases. The 2,069 colonoscopies included 1,878 biopsies, 353 polypectomies, and 139 other procedures. Some patients had multiple therapeutic interventions. Findings included 2,107 polyps, the pathology of which included 907 tubular; 62 tubulovillous and 41 villous adenomas, 325 hyperplastic polyps, and 68 carcinomas. There were five major complications after polypectomies (0.2%) including two cases of bleeding and three perforations. The two patients with bleeding were admitted to hospital, one for observation for 2 days and the other for colonoscopy, coagulation, and transfusion of 3 units of blood. Of the three patients with perforation, one underwent hospitalization for intravenous antibiotics and the other two for surgery (0.01%). Surgery included one resection with primary closure of the sigmoid perforation and one colostomy. CONCLUSIONS: This study confirms the observation that colonoscopy performed by surgeons is safe and rapid whether performed as a therapeutic or as a diagnostic procedure.

Adolescent↗