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Dive into the research topics where David J. Ott is active.

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Featured researches published by David J. Ott.


Journal of Surgical Oncology | 1997

Assessment of rectal tumor infiltration utilizing endorectal MR imaging and comparison with endoscopic rectal sonography

Ronald J. Zagoria; Christopher A. Schlarb; David J. Ott; Robert E. Bechtold; Neil T. Wolfman; Eric S. Scharling; Michael Y. M. Chen; Brian W. Loggie

The preoperative assessment of depth of invasion of rectal carcinoma is increasingly important as new treatment methodologies are developed. Accuracy of preoperative endorectal MR imaging was therefore compared with that of the endoscopic rectal sonography in determining depth of invasion of rectal carcinomas.


Dysphagia | 1996

Modified barium swallow: clinical and radiographic correlation and relation to feeding recommendations

David J. Ott; Richard G. Hodge; Leigh Ann Pikna; Michael Y. M. Chen; David W. Gelfand

Clinical and videofluoroscopic evaluation of swallowing were correlated to determine their agreement and relationship to feeding recommendations. We reviewed a total of 148 patients with swallowing difficulties, of which 93 (45 women, 48 men; mean age 62 years) were evaluated by both clinical and radiographic examinations. A variety of materials were used for clinical bedside evaluation of oral and pharyngeal function. Radiographic examination was done with variable viscosity materials and videotape recording of the oral cavity and pharynx. The severity of oral and pharyngeal abnormalities was graded and findings of the examinations were compared. The combined results of both evaluations generated an index of swallowing difficulty which was correlated to the type of diet used if oral feeding was recommended or to a nonoral route of nutrition. In the assessment of oral and pharyngeal dysfunction, clinical evaluation and radiographic examination correlated closely in 94% of patients; however, the status of pharyngeal function was not determined in 61 (66%) of the 93 patients by clinical examination alone. The combined swallowing index was calculated in 89 patients and its severity correlated significantly with the type of feeding recommended; 64 patients were placed on one of three types of diets and 25 had enteral feedings. In conclusion, combined clinical and radiographic examinations correlated well, but clinical evaluation alone was limited by failure to evaluate the pharynx in many patients. The swallowing severity correlated well with final feeding recommendations.


Radiology | 1979

Reflux Esophagitis: Radiographic and Endoscopic Correlation

David J. Ott; David W. Gelfand; Wallace C. Wu

Although the value of endoscopy in reflux esophagitis is accepted, the role of radiology has not been well defined. The radiographic and endoscopic findings in 75 patients were correlated. A grading system was employed to stage the severity of involvement. Thirty-five appeared normal on endoscopy and 40 had esophagitis of differing stages of severity. The results indicate that radiography is insensitive in mild degrees of inflammation but that its sensitivity and accuracy improves in more severe grades of esophagitis.


Abdominal Imaging | 1985

Predictive relationship of hiatal hernia to reflux esophagitis

David J. Ott; David W. Gelfand; Yu Men Chen; Wallace C. Wu; H. A. Munitz

The relationship between hiatal hernia and reflux esophagitis was compared in 93 patients who underwent both radiographic and endoscopic examination of the esophagus. In 46 patients with a normal esophagus shown endoscopically, hiatal hernia was present in 59%, while 94% of 47 patients with reflux esophagitis had hiatal hernia. The positive and negative predictive values for hiatal hernia in diagnosing or excluding esophagitis were 62% and 86%, respectively. Extrapolation of these data and review of the literature suggest that much of the confusion concerning the relationship between hiatal hernia and reflux esophagitis is based on reports of populations with considerable variation in the prevalence of esophagitis and in which the radiographie criteria for diagnosing hiatal hernia have not been uniformly applied.


Abdominal Imaging | 1985

Multiphasic examination of the esophagogastric region for strictures, rings, and hiatal hernia: evaluation of the individual techniques

Yu Men Chen; David J. Ott; David W. Gelfand; H. A. Munitz

Three hundred multiphasic examinations of the lower esophagus and esophagogastric region were assessed to determine the individual sensitivities of the full-column, mucosal relief, and double contrast techniques in the detection of common structural abnormalities, such as hiatal hernia, lower esophageal rings, and peptic strictures. In 159 patients, there were 211 structural abnormalities including 153 hiatal hernias, 35 mucosal rings, 20 peptic strictures, and 3 esophageal diverticula. The overall sensitivity of the full-column technique in detecting these abnormalities was 100% compared to 52% and 34% for the mucosal relief and double-contrast techniques, respectively. We conclude that the prone full-column technique must be incorporated into any examination of the esophagogastric region if these common abnormalities are to be demonstrated reliably.


Abdominal Imaging | 1981

Reflux esophagitis revisited: Prospective analysis of radiologic accuracy

David J. Ott; Wallace C. Wu; David W. Gelfand

A prospective radiologic-endoscopic study of the esophagogastric region in 266 patients, including 206 normals and 60 with esophagitis, is reported. The endoscopic classification grading severity of esophagitis was grade 1 — normal; grades 2, 3, and 4 — mild, moderate, and severe esophagitis, respectively. Radiology detected 22% of patients with mild esophagitis, 83% with moderate esophagitis, and 95% with severe esophagitis. Although hiatal hernia was present in 40% of normals and 89% with esophagitis, absence of radiographic hiatal hernia excluded esophagitis with 95% accuracy. The implications of this study regarding the role of radiology in evaluating patients with suspected reflux esophagitis are discussed.


Journal of Computer Assisted Tomography | 1997

Interpretation of abdominal CT: Analysis of errors and their causes

Robert E. Bechtold; Michael Y. M. Chen; David J. Ott; Ronald J. Zagoria; Eric S. Scharling; Neil T. Wolfman; David J. Vining

PURPOSE Our goal was to analyze those factors contributing to the error rate in the interpretation of abdominal CT scans at an academic medical center. METHOD From a total of 694 consecutive patients (329 male, 365 female), we evaluated the error rates of interpreting abdominal CT studies. The average patient age was 54 years. All abdominal CT studies were reviewed by three to five CT faculty radiologists on the morning after the studies were performed. The error rate was correlated with reader variability, the number of cases read per day, the presence of a resident, inpatient versus outpatient, organ systems, etc. The chi 2-test was used for statistical analysis. RESULTS A total of 56 errors were found in the reports of 53 patients (overall error rate = 7.6%). Of these errors, 19 were judged to be clinically significant and 7 affected patient management. A statistically significant difference in error rates was noted among the five faculty radiologists (3.6-16.1%, p = 0.00062). No significant correlates between error rates and any of the other variables could be established. CONCLUSION The primary determinant of error rates in body CT is the skill of the interpreting radiologist.


Abdominal Imaging | 1981

Complications of gastrointestinal radiologic procedures: II. Complications related to biliary tract studies

David J. Ott; David W. Gelfand

Since production of the first cholecystogram by Graham and Cole in 1924 [1], a number of compounds have been developed for oral cholecystography (OCG). In 1952, following observations on a series of aryl triiodo alkanoic acid derivatives, Hoppe and Archer introduced iopanoic acid (Telepaque| [2]. The triiodinated aromatic ring of this compound became the general structure for all modern OCG agents (Fig. 1). Telepaque remains the most widely used gallbladder contrast medium, and over 40 million


Gastrointestinal Endoscopy | 1996

Radiation exposure during ERCP: effect of a protective shield

Michael Y. M. Chen; Frederick L. Van Swearingen; Richard Mitchell; David J. Ott

OBJECTIVES To measure the radiation exposure to endoscopists, patients, and assistants during diagnostic and therapeutic ERCP and to assess the effect of a protective lead shield. Radiation dose with and without the protective lead shield was mapped in our standard fluoroscopy room. MATERIALS AND METHODS Twenty patients undergoing ERCP were selected for this study. Radiation exposure of endoscopists with and without a protective shield was monitored by digital dosimeter. Radiation exposure for diagnostic procedures was correlated with that of therapeutic procedures. RESULTS Endoscopists were exposed to 2.5 mR without the protective shield, but exposure was reduced to an average of 0.27 mR per procedure with the shield. Endoscopists received an average of 1.5 mR per diagnostic ERCP and 3.17 mR per therapeutic ERCP without the shield. When using the protective shield, however, those numbers were reduced to an average of 0.25 mR per diagnostic procedure and 0.28 mR per therapeutic procedure. Radiation exposure to endoscopic assistants, who were not shielded, averaged 0.56 mR per procedure. CONCLUSION Amount of radiation exposure to occupational personnel during ERCP was related to duration of fluoroscopy and type of procedure. Radiation exposure to endoscopists can be significantly reduced by the use of a protective shield. Medical assistants received less radiation than did endoscopists because the assistants position was more distant from x-ray sources.


Digestive Diseases and Sciences | 1987

Radiographic evaluation of esophagus immediately after pneumatic dilatation for achalasia.

David J. Ott; Joel E. Richter; Wallace C. Wu; Yu Men Chen; Donald O. Castell; David W. Gelfand

Forty-one (98%) of 42 patients with achalasia of the esophagus had pneumatic dilatation performed successfully using the Brown-McHardy dilator. One to four dilatations (mean, 1.9) were done on each patient with inflation pressures of 8–15 psi (mean, 11.1 psi). Immediately after the procedure, all patients were examined radiographically by injection of contrast material into the lower esophagus through a nasoesophageal tube. Two immediate and two delayed perforations occurred. Six intramural hematomas were noted, five of which resolved spontaneously. The luminal diameter at the esophagogastric junction increased from a mean of 4.2 mm before dilatation to 7.5 mm following treatment. Four patients with previous Heller myotomy were dilated without complications. Perforation was more common in patients with a minimal change in the esophagogastric diameter. Thirty-five patients (85%) improved symptomatically within several days following pneumatic dilatation. Excluding patients with perforation, the postdilatation appearance of the lower esophagus poorly correlated with clinical response.

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Wallace C. Wu

Medical College of Wisconsin

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Yu Men Chen

Wake Forest University

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Mym Chen

Wake Forest University

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Joel E. Richter

University of South Florida

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