Eric S. Scharling

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

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.

Ultrasonographic diagnosis of varicoceles

OBJECTIVE To assess the ability of color duplex scrotal ultrasonography to detect subclinical varicoceles and confirm the diagnosis of clinical varicoceles. DESIGN Physical examination, color duplex scrotal ultrasonography and internal spermatic venography was performed on 64 testicular units in 33 men. SETTING Male fertility center. PATIENTS Two hundred sixty-two consecutive men being evaluated for male factor infertility of whom 33 agreed to undergo venography. MAIN OUTCOME MEASURES Ultrasonographic measurement of scrotal vein diameter of patients in the supine and upright position, before and during valsalva maneuver, and scrotal vein blood flow reversal with valsalva maneuver was compared with the findings of varicocele by physical examination and venography. RESULTS The best predictor of a varicocele was internal spermatic vein diameter, and the best overall performance of ultrasonography was achieved with the patient at rest in the supine position. The best cutoff point for venous diameter for a clinical varicocele was 3.6 mm and 2.7 mm for a subclinical varicocele, but the overall accuracy was only 63%. CONCLUSIONS Confirmatory studies are needed to support the ultrasonographic diagnosis of varicoceles before considering surgical repair.

Interpretation of abdominal CT: Analysis of errors and their causes

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.

Spontaneous Perinephric Hemorrhage: Imaging and Management

We report on 10 patients with spontaneous perinephric hemorrhage associated with underlying disease, including renal cell carcinoma (5), angiomyolipoma (2), malignant melanoma (1), periarteritis nodosa (1) and severe portal hypertension (1). The etiology could not be identified with computerized tomography (CT) in 5 cases (50%), including 2 renal cell carcinomas, 1 angiomyolipoma, 1 periarteritis nodosa and 1 portal hypertension. Arteriography demonstrated underlying lesions in 4 of these 5 cases (80%) including the case of vasculitis. CT combined with magnetic resonance imaging is accurate for the diagnosis of spontaneous perinephric hemorrhage but the underlying pathological condition is often undetectable in the acute phase due to the perinephric blood. CT should be the first study performed if this diagnosis is suspected. Arteriography is recommended if a renal mass is not detected. If a mass is not identified with these 2 imaging studies and the patient is clinically stable, followup thin slice CT should be performed.

Computed tomography evaluation of colorectal carcinoma.

Knowledge of the extent of primary colorectal carcinoma at initial diagnosis is critical for proper management of disease. Currently, CT does not have a role in screening for colorectal carcinoma, though promising work on virtual colonoscopy is on the horizon. In patients with proven colorectal carcinoma, accurate prospective noninvasive assessment can identify those who may benefit from preoperative local radiotherapy, hepatic resection or cryoablation, or intra-arterial chemotherapy. CT should be considered complementary to the clinical assessment of colorectal carcinoma and to other modalities, such as barium enema, endorectal ultrasonography, MRI, and immunoscintigraphy. Although limited in evaluation of the primary tumor and local spread, CT has proven useful in assessing patients thought to harbor extensive local or metastatic disease. CT is generally the modality of choice for imaging the postoperative patient. The cross-sectional display of CT clearly depicts the operative bed, particularly after abdominoperineal resection. Baseline examinations should be obtained 2 to 4 months after surgery, with follow-up examinations every 6 to 9 months for 2 years, and yearly studies thereafter. CT-guided biopsies should be performed when findings suggest recurrent carcinoma.

CT diagnosis of acute flank pain from urolithiasis

The use of noncontrast helical CT (NHCT) to assess patients with acute flank pain and hematuria for potential urinary tract stone disease was first reported in 1995. After several years of experience with the technique, sensitivity and specificity of NHCT has proven to be better than intravenous urography for evaluating ureteral stones. NHCT imaging findings for urinary calculi and the differential diagnosis are discussed in this article. Various extraurinary diseases found while using NHCT in searching for stone disease are addressed and illustrated. As experience with the use of NHCT has increased, clinicians have broadened the indications for this technique, which has a lower charge than standard CT, beyond the specific evaluation of urinary colic. This indication creep has increased the number of NHCT examinations ordered. It has also reduced the rate of stone positivity and increased the diagnostic yield for extraurinary disease.

ACUTE PANCREATITIS: THE ROLE OF DIAGNOSTIC IMAGING

In the U.S., acute pancreatitis is usually caused by excessive consumption of ethanol or by biliary stone disease. Major pathologic finding and complications include fluid collections within the organ or the adjacent peripancreatic tissues, pseudocysts, pancreatic necrosis, pseudoaneurysm, and abscess formation. Radiologic imaging, including endoscopic retrograde cholangiopancreatography (ERCP), sonography, and computed tomography (CT), are important in the evaluation of acute pancreatitis and its complications. CT in particular also aids in grading the severity of acute pancreatitis and in predicting complications and mortality; however, CT correlation with Ransons clinical prognostic factors or with other classification systems is less clear. The imaging and therapeutic aspects of acute pancreatitis are discussed and illustrated and prognostic factors are correlated.

Overview of Imaging in Colorectal Cancer

Accurate staging of colorectal carcinoma (CRC) at initial diagnosis is critical for proper management of this disease. Computed tomography (CT) is often used for preoperative staging and is complementary to the clinical assessment of the patient and to the use of other imaging techniques, such as endoluminal ultrasound (US). CT can identify those patients who may benefit from local radiation therapy, hepatic resection or cryoablation, or intra-arterial chemotherapy. Endoluminal US may detect patients with early disease and alter their course of therapy, especially in those with rectal carcinoma in which limited surgery might be performed. CT is generally the modality of choice for imaging the postoperative patient. CT clearly depicts the operative area, particularly after abdominoperitoneal resection, and can be used to guide percutaneous biopsy of masses. The role of magnetic resonance imaging in CRC remains to be defined. In this review, we discuss the current roles of these various imaging modalities in the management of this disease.

Colitis: Causes, Pathology, and Imaging

This pictorial review discusses and illustrates the various idiopathic types of inflammatory bowel disease as well as those related to specific causes. Idiopathic colitis includes ulcerative colitis and Crohn’s disease of the colon; the non-idiopathic forms reviewed are infectious colitis, pseudomembranous colitis, typhlitis, ischemic colitis, and graft-versus-host disease. The causes, pathology, clinical presentation, and radiographic findings are described for each disorder. The radiographic findings are emphasized, with a focus on plain radiographs, barium enema, and CT examinations. The differential considerations, patterns of colonic involvement, mucosal surface changes, specific features, and complications are reviewed and summarized.

Small Bowel Neoplasms: Evaluation with CT

Tumors of the small intestine are uncommon; they account for only 2% to 6% of gastrointestinal neoplasms. Computed tomography (CT) can play a significant role in both the detection and charaterization of these lesions. The clinical presentation of small bowel neoplamss include complaints of weight loss, abdominal pain, diarrhea, gastrointestinal hemorrhage, or an abdominal mass. CT may be requested as the iniital radiologic screening examination for patients with these nonspecific complaints; therefore, it is important for radiologists to be familiar with the CT findings of small bowel neoplasms. CT should be considered complementary to conventioanl barium examinations and endoscopy. Althuogh the latter techniques have proven reliable in identifying intraluminal and muscosal tumors. CT is superior for delineating submucosal, intramural, and exophyti tumor extension. Extraintestinal spread of tumor to adjacent structures, mesentery, peritoneum, reroperitoneum, and solid organs is also best demonstrated with CT. In some cases, the CT characteristics of the primary tumor mass and ancillary disease are suggestive of specific tumor types, and proper treatment can begin without the need for further studies.The purpose of this lesson is to outline theCT findings of the various msll bowel tumors and to emphasize specifically those CT characteristics that may help the radiologist to make a specific diagnosis of tumor type.