Comparing the Diagnostic Accuracy of Ultrasound and CT in Evaluating Acute Cholecystitis.

OBJECTIVE: In 2013, a multidisciplinary group at our Veterans Administration hospital collaborated to improve the diagnosis and treatment of patients with acute cholecystitis (AC) at our facility. Our role in this project was to evaluate the diagnostic accuracies of ultrasound (US) and CT. MATERIALS AND METHODS: AC was diagnosed in 60 patients (62 patient encounters) between July 1, 2013, and July 1, 2015. Of these patients, 56 underwent US, 48 underwent CT, and 42 underwent both. For the same time period, 60 patients without AC underwent US and 60 patients without AC underwent CT, and these imaging studies served as comparison studies. The groups were combined for a total of 182 unique patient encounters. A single radiologist reviewed the studies and tabulated the data. RESULTS: The sensitivity of CT for detecting AC was significantly greater than that of US: 85% versus 68% (p = 0.043), respectively; however, the negative predictive values of CT and US did not differ significantly: 90% versus 77% (p = 0.24-0.26). Because there were no false-positives, the specificity and positive predictive values for both modalities were 100%. Among the 42 patients who underwent CT and US, both modalities were positive for AC in 25 patients, CT was positive and US was negative in 10 patients, and US was positive and CT was negative in two patients; in five patients, both US and CT were negative. CONCLUSION: CT was significantly more sensitive for diagnosing AC than US. CT and US are complementary, and the other modality should be considered if there is high clinical suspicion for AC and the results of the first examination are negative.

Large-Bowel Obstruction in the Adult: Classic Radiographic and CT Findings, Etiology, and Mimics.

Large-bowel obstruction is an abdominal emergency with high morbidity and mortality rates if left untreated. Although abdominal radiography is usually the initial imaging study performed in patients suspected of having large-bowel obstruction, it may not be sufficient to distinguish obstruction from other causes of colonic dilatation. Computed tomography is the imaging method of choice as it can establish the diagnosis and cause of large-bowel obstruction. A contrast agent enema may be used to confirm or exclude large-bowel obstruction. In this review, the imaging findings in multiple causes of large-bowel obstruction are illustrated and compared with acute colonic pseudo-obstruction.

Review of small-bowel obstruction: the diagnosis and when to worry.

This is a review of small-bowel obstruction written primarily for residents. The review focuses on radiography and computed tomography (CT) for diagnosing small-bowel obstruction and CT for determining complications. (©) RSNA, 2015.

The gallbladder: what's new in 2022?

This review focuses mainly on the imaging diagnosis, treatment, and complications of acute cholecystitis which is the most common benign disease of the gallbladder. The American College of Radiology appropriateness criteria for the imaging evaluation of patients with right upper quadrant pain and the Tokyo Guidelines for evaluating patients with acute cholecystitis and acute cholangitis are presented. The recent articles for using US, CT, MR, and HIDA in the evaluation of patients with suspected acute cholecystitis are reviewed in detail. The clinical management and postoperative complications are described. Because gallbladder polyps and adenomyomatosis can mimic gallbladder malignancies and acute cholecystitis, their imaging findings and management are presented. Finally, due the recent literature reporting better results with CT than US in the diagnosis of acute cholecystitis, a suggested approach for imaging patients with right upper quadrant pain and possible acute cholecystitis is presented in an addendum.

A multimodality review of male urethral imaging: pearls and pitfalls with an update on urethral stricture treatment.

Optimum radiological assessment of the male urethra requires knowledge of the normal urethral anatomy and ideal imaging techniques based on the specific clinical scenario. Retrograde urethrography is the workhorse examination for male urethral imaging, usually utilized as the initial, and often solitary, modality of choice not only in the setting of trauma, but also in the pre- and post-operative evaluation of urethral strictures. There is, however, growing interest in utilization of ultrasound and magnetic resonance for evaluation of the male urethra owing to lack of ionizing radiation and improved delineation of the adjacent tissue. We review the various modalities utilized for imaging of the male urethra for a variety of known or suspected disorders, and provide an update on current treatments of urethral strictures. Additionally, we detail the key information needed by urologists to guide management of urethral strictures. We conclude with a brief discussion of neophallus urethral diseases following female-to-male sexual confirmation surgery.

Pneumatosis intestinalis and pneumoperitoneum after bilateral lung transplantation in adults.

OBJECTIVE: The purpose of this article is to determine the clinical features, imaging findings, and possible causes of pneumatosis intestinalis (PI) or pneumoperitoneum that developed in bilateral lung transplant recipients. MATERIALS AND METHODS: From December 2004 to July 2009, seven (2%) of 321 bilateral lung transplant recipients (two women and five men; age range, 25-66 years) who developed PI or pneumoperitoneum, or both, were identified. Medical records were reviewed to determine the clinical presentation, laboratory findings, and medications at the time of presentation of PI or pneumoperitoneum. Hospital course and time to resolution of PI or pneumoperitoneum were recorded. Common factors that might explain the cause of the PI and pneumoperitoneum were evaluated. Two experienced abdominal radiologists reviewed all imaging studies and recorded the specific findings for each patient. RESULTS: All patients had minimal or no symptoms, normal laboratory study results, and no systemic, intestinal, or proven respiratory infections. All patients but one were receiving triple immunosuppressive agents (i.e., prednisone, azathioprine, and tacrolimus). The imaging findings were similar in five of the patients with the PI dominated by a linear and cystic appearance and involving only the colon. Three of the six patients with PI had both PI and pneumoperitoneum. The mean time to resolution of PI was 24 days. No definite cause for the PI and pneumoperitoneum could be determined in the seven patients. CONCLUSION: Bilateral lung transplant recipients may develop benign PI or pneumoperitoneum after surgery. Benign PI in bilateral lung transplant recipients has a similar and specific linear and cystic appearance and is not due to ischemic bowel. No specific cause for the PI and pneumoperitoneum could be determined.

The effect of ACGME duty hour restrictions on operative continuity of care.

Resident work restrictions limit participation in operations that address problems created by a prior operation, because complications occur at any time. We compared resident and attending surgeon staffing of operative complications. We reviewed all complications that required a second operation reported at our Morbidity and Mortality Conference over 1 year, noting surgeons present, their postgraduate year level, and call shift. Comparisons were done using chi2. Of 142 cases, 39 involved a second operation. The same attending surgeon was present for both in 79 per cent of cases, whereas the same resident was present in only 44 per cent (P = 0.002). Postgraduate year 4 to 5 were less likely to be present for second operations than attendings (48% vs 87%, P = 0.011). Resident shift (day, night float, and weekend) was known in 32 cases. When the first operation occurred during day hours, attendings and residents were equally likely to be present at the second (55% and 45%, P = 0.16). When original operations took place during night float or weekend shifts, residents were less likely to be present (33%) than attendings (83%) at second operations (P = 0.036). Duty hour restrictions interfere with operative continuity of care. Reoperations should be exempted from duty hour restrictions.

Gasless abdomen in the adult: what does it mean?

OBJECTIVE: The objective of this article is to illustrate the causes of a gasless abdomen in an adult. CONCLUSION: The gasless abdomen in the adult is often interpreted as nonspecific, which does not provide useful information for the patient's physician. There are at least six causes of the gasless abdomen in the adult. A specific cause of the gasless abdomen can usually be made when the patient's history is known. The most serious cause of the gasless abdomen is small-bowel obstruction with or without ischemia.

Pneumatosis intestinalis in the adult: benign to life-threatening causes.

OBJECTIVE: The frequency of detection of pneumatosis intestinalis (PI) appears to be increasing. This increase may be the result of increased CT use. New medications and surgical procedures have been reported to be associated with an increase in the incidence of PI. The purpose of this review is to provide an update on the imaging features and clinical conditions associated with PI. CONCLUSION: This article illustrates the imaging findings of PI due to benign and life-threatening causes, with emphasis placed on describing newly associated conditions and also the imaging appearance on CT.

Accuracy of abdominal radiography in acute small-bowel obstruction: does reviewer experience matter?

OBJECTIVE: The purposes of this study were to determine the accuracy of abdominal radiography in the detection of acute small-bowel obstruction (SBO), to assess the role of reviewer experience, and to evaluate individual radiographic signs of SBO. MATERIALS AND METHODS: A retrospective study was performed in which the subjects were 90 patients with suspected SBO who underwent CT and abdominal radiography within 48 hours of each other. The patients were enrolled from June 1, 2003, to February 2004. Twenty-nine of the patients had proven SBO. Hard-copy radiographs were reviewed by three groups of radiologists: senior staff, junior staff, and second-year radiology residents. Each reviewer evaluated the quality of the radiographs, patient position for acquisition of the radiographs, and whether SBO was present. The reviewers rated their confidence on a five-point scale and recorded the presence or absence of specific radiographic signs of SBO. Chi-square tests were used to compare the three groups. A statistically significant finding was considered p < 0.05. Receiver operating characteristic (ROC) curves were fit with a 10-point confidence scale. RESULTS: The sensitivity for SBO among the six reviewers ranged from 59% to 93%. The senior staff members were significantly more accurate. The mean sensitivity, specificity, and accuracy for all six reviewers were 82%, 83%, and 83%, respectively. Three radiographic signs were highly significant (p < 0.001): two or more air-fluid levels, air-fluid levels wider than 2.5 cm, and air-fluid levels differing more than 5 mm from one another in the same loop of small bowel. ROC analysis showed that senior staff is significantly more accurate than the other groups in the detection of acute SBO. CONCLUSION: Our results confirmed that abdominal radiographs are accurate in the detection of acute SBO, that more-experienced radiologists are more accurate than less-experienced reviewers in the evaluation of abdominal radiographs, and that three types of air-fluid levels are highly predictive of the presence of SBO.

Comparison of radiologists and technologists in the performance of air-contrast barium enemas.

OBJECTIVE: The purpose of this study was to determine whether the rate of polyp detection and the quality of air-contrast barium enema (ACBE) procedures performed by technologists differ from those performed by radiologists. CONCLUSION: Our results showed that well-trained certified technologists can perform ACBE similar in overall quality and accuracy to ACBE performed by attending physicians and residents. Training technologists to perform ACBE may help to alleviate the radiology staffing shortage in the United States.

Impedance cardiography: can it replace thermodilution and the pulmonary artery catheter?

Clinical assessment of cardiac output (CO) is inaccurate, yet the use of the pulmonary artery catheter (PAC) for thermodilution (TD) measurement of CO (CO(TD)) has declined significantly. Can noninvasive impedance cardiography (ICG) now be used to measure CO (CO(ICG)) in place of CO(TD)? A literature review of recent CO(ICG) correlations with CO(TD) (r = 0.73-0.92) were similar to ours, r = 0.81. A search for conditions interfering with CO(ICG) revealed no serious problems with patient position, cardiac or pulmonary assist devices, "wet lungs," body mass index > or = 30, or age > or = 70 years. A prospective randomized study was initiated beginning with a record of physician assessment of CO as high, normal, or low; concordance was 57%. Data from ICG was revealed only in the study group, resulting in a 49 per cent change in treatment compared with 29 per cent in the control group. Length of stay was shorter in the study than the control group in the intensive care unit (2.4 +/- 8.8 vs 3.3 +/- 7.3 days) and on the floor (9.8 +/- 10.6 vs 15.7 +/- 19.0 days). In conclusion, ICG is comparable with TD, is easily, accurately, and safely performed, enhances clinical assessment of CO, and improves care in hemodynamically compromised patients.

Peptic ulcer disease in the Alaska Natives: a four-year (1967-1971) retrospective study.

A four-year retrospective study of peptic ulcer disease in the Alaska Native confirmed our suspicion of a decreased ratio of duodenal to gastric ulcers. There were 92 patients with duo-denal ulcers, 75 with gastric ulcers, 6 with carcinoma of the stomach and 1 with gastric sarcoma. Ulcer disease in the Alaska Natives differs from ulcer disease among the Southwestern Indians as reported by Sievers.

Ectopic thyroid.

Primary mediastinal ectopic goiters are very rare. We report a case in which an ectopic goiter with blood supply from the thoracic vessels necessitated a transternal approach for removal, resulting in a favorable outcome.

From the archives of the AFIP: primary vascular neoplasms of the spleen: radiologic-pathologic correlation.

Primary vascular neoplasms of the spleen constitute the majority of nonhematolymphoid splenic tumors. The benign primary vascular tumors include hemangioma, hamartoma, and lymphangioma, whereas those of variable or uncertain biologic behavior include littoral cell angioma, hemangioendothelioma, and hemangiopericytoma. The primary malignant vascular neoplasm of the spleen is angiosarcoma. Peliosis is a rare lesion of unknown cause that is usually found incidentally in asymptomatic patients but may be associated with hematologic or metastatic disease. Although these vascular neoplasms of the spleen are uncommon, their importance lies in that they must be differentiated from the more common neoplastic disorders of the spleen, such as lymphoma and metastasis. The most common echogenic solid or complex cystic mass in an asymptomatic patient is splenic hemangioma. However, the imaging appearance of splenic hemangiomas may be complex, and differentiation of these lesions from malignant disease may not be possible. The diagnosis of splenic hamartoma may be suggested when findings of increased blood flow on color Doppler images are seen in association with a homogeneous solid echogenic mass. A large subcapsular solitary cystic abnormality discovered incidentally in a child in association with internal septations and tiny mural nodules favors the diagnosis of lymphangioma. Any invasion of the surrounding splenic parenchyma by a splenic lesion should indicate a more aggressive or malignant process. Evaluation of a focal splenic abnormality identified on sonograms should be followed up with computed tomography or magnetic resonance imaging with and without contrast material enhancement. Splenectomy may be required for definitive evaluation of a splenic mass with atypical features.

Esophageal actinomycosis: a case report and review of radiographic findings.

Esophageal Actinomycosis is a rare disease with only two previous reports in the Radiology literature. We present a 27 year-old African American male with a past medical history of a renal transplant for renal disease secondary to lupus who presented with odynophagia. The computed tomography and barium swallow findings are presented as well as a differential diagnosis of infectious esophageal diseases.