Surgical and pathologic correlation of cholecystosonography and cholecystography.

To define the accuracy of varying ultrasonic patterns in the diagnosis of gallstones, the records of 145 patients with ultrasound examination of the gallbladder prior to cholecystectomy were reviewed. Three abnormal scan categories were established: category 1--shadowing opacities that move with gravity within the gallbladder lumen; category 2--nonvisualization of the gallbladder lumen; and category 3--nonshadowing opacities within the gallbladder lumen. The accuracy of these criteria for gallstone diagnosis was found to be 100%, 96%, and 61%, respectively. Overall accuracy was 96% for gallbladder disease, with a 4% false negative rate. Oral cholecystography demonstrated an accuracy of 93% in this series. A preoperative ultrasound diagnosis of gallstones should probably be limited to category 1 and 2 appearances only.     

Gray scale ultrasonography of the gallbladder: an evaluation of accuracy and report of additional ultrasound signs.

Ultrasound examinations of 76 patients with suspected gallbladder disease were compared with radiographic, surgical, and pathologic findings to determine the accuracy of the ultrasound examinations. In 13 of the 76, the gallbladder was not visualized by ultrasound. Diagnosis of the presence or absence of gallstones was correctly made by ultrasound in 56 of 63 visualized gallbladders, for an accuracy rate of 89%. A high proprtion of nonvisualized gallbladders (10 or 13) contained gallstones. Previously unreported ultrasound findings of a stone impacted in the proximal cystic duct and findings of a collection of bile in the lesser sac associated with cholelithiasis and choledocholithiasis are illustrated.     

Sensitivity of ultrasonography for detecting gallstones

Previous studies have overestimated the accuracy of ultrasonography for the diagnosis of gallstones by neglecting the systematic checking of false negative findings. In the present series only 80% of 331 cases of gallstones seen at autopsy had been detected by ultrasonography. The most frequent reason for a false negative finding was the small size of the gallstones.     

Cholelithiasis in sickle cell disease: a cholecystographic and ultrasonographic evaluation in Nigerians

A prospective study designed to establish the incidence of gallstones among 48 Nigerian homozygous sickle cell disease patients was made using oral cholecystography and grey-scale ultrasonography. The age range was 2 to 35 years with a mean of 16 years. The youngest patient with gallstones was a 51/2-year-old boy. Gallstones were demonstrated on cholecystosonography in 12 of 48 patients (25%). The incidence of cholelithiasis was 7.7% in children 10 years or younger and 31.4% in patients above this age. There was no correlation between the incidence of cholelithiasis and serum bilirubin on one hand and positive history of abdominal pain on the other. Screening of patients over 15 years for gallstones is suggested with a view to performing elective cholecystectomy in patients who subsequently become symptomatic.     

The prospective diagnostic value of real-time cholecystosonography

A series of 82 consecutive patients scheduled for operation, with pre-operatively obtained P.O. cholecystography and in some cases also I.V. cholangiography, is presented. All patients had cholecystosonography performed "blindly" the day prior to the operation (76 had a cholecystectomy and six had a vagotomy). Based upon the operative findings, the diagnostic value of ultrasonic examination for gallstones can be calculated to predictive value of positive test--1.00; predictive value of negative test--0.71. The diagnostic failures are discussed but it is not possible to predict which patients will benefit more from peroral cholecystography rather than from ultrasound. It is concluded that cholecystosonography is a safe alternative to peroral cholecystography.     

Cholescintigraphy in the detection of cholelithiasis: A review of 23 cases and a case report demonstrating the sequential evolution of the appearance of the gallbladder defect

Cholescintigraphy of cholelithiasis has been reported as a defect or photon deficient area in the gallbladder. We present the case of a patient with gallstones whose cholescintigraphic study showed a sequential evaluation of the scan appearance from a defect, to a septation, a hole, and finally a filled-in appearance. Cholescintigrams and histopathologic findings after cholecystectomy of another 22 patients with cholelithiasis were also retrospectively reviewed. The results of the study concluded that: (1) cholelithiasis is rarely demonstrated by cholescintigraphy and (2) nonvisualization of the gallbladder may be due to acute or chronic cholecystitis associated with cholelithiasis.     

Cholescintigraphy in the detection of cholelithiasis: a review of 23 cases and a case report demonstrating the sequential evolution of the appearance of the gallbladder defect

Cholescintigraphy of cholelithiasis has been reported as a defect or photon deficient area in the gallbladder. We present the case of a patient with gallstones whose cholescintigraphic study showed a sequential evaluation of the scan appearance from a defect, to a septation, a hole, and finally a filled-in appearance. Cholescintigrams and histopathologic findings after cholecystectomy of another 22 patients with cholelithiasis were also retrospectively reviewed. The results of the study concluded that: cholelithiasis is rarely demonstrated by cholescintigraphy and nonvisualization of the gallbladder may be due to acute or chronic cholecystitis associated with cholelithiasis.     

Intraperitoneal spilled gallstones presenting as fever of unknown origin after laparoscopic cholecystectomy: FDG PET/CT findings

An otherwise healthy 63-year-old man who had undergone emergency laparoscopic cholecystectomy for acute calculous cholecystitis 6 weeks earlier developed daily fever for more than 3 weeks, malaise, weight loss, and elevated erythrocyte sedimentation rate. Initial imaging procedures (abdominal ultrasound and chest radiograph) were normal. The diagnosis of fever of unknown origin was established, and a whole-body FDG PET/CT scan was performed. PET/CT showed inflammatory changes corresponding to spilled intraperitoneal gallstones. We have described the PET/CT findings of spilled intraperitoneal gallstones, a relatively common complication of laparoscopic cholecystectomy.     

Radiologic features of complications arising from dropped gallstones in laparoscopic cholecystectomy patients

OBJECTIVE: Because laparoscopic cholecystectomy has become the accepted treatment for symptomatic cholelithiasis, radiologists frequently encounter patients who have had this surgery. Although the radiologic features of postoperative bile duct injury are well documented, the imaging features of less well-known complications remain poorly described. One such unusual complication is abscess formation caused by dropped gallstones. CONCLUSION: Although the incidence of dropped gallstones is an uncommon complication of laparoscopic cholecystectomy, it should be recognized as a potential source of both intraabdominal and intrathoracic abscess formation in any patient presenting months to years after undergoing laparoscopic cholecystectomy. These abscesses are not necessarily confined to the right upper quadrant.     

The role of ultrasound in the detection of non-radiopaque foreign bodies

Fifty consecutive ultrasound examinations performed for suspected non-radiopaque foreign bodies in extremities were reviewed to establish the value of this procedure. Ultrasound detected 21 of 22 foreign bodies found at operation. There were three false positive examinations. The sensitivity was 95.4%, the specificity 89.2%, the positive predictive value 87.5% and the negative predictive value was 96.2%. This study demonstrates that ultrasound is a reliable method for detecting non-radiopaque foreign bodies and makes a significant contribution to patient management.     

The value of ultrasound in predicting non-visualization of the gall-bladder on OCG: implications for imaging strategies in patient selection for non-surgical therapy of gallstones

Gall-bladder visualization on oral cholecystography (OCG) is required for most non-surgical therapies of gallstones. In this study we attempted to establish sonographic criteria which will predict non-visualization of the gall-bladder on OCG. For this purpose we compared the results of ultrasound (US) and OCG in 171 patients with gallstones being assessed for non-surgical therapy. Sonographic criteria for non-visualization were a contracted gall-bladder and stone impaction in the gall-bladder neck or cystic duct. In detecting findings which predict non-visualization on OCG, US had a sensitivity of 78.3% and a specificity of 97.6%. The predictive values were: positive findings 92.3% and negative findings 92.4%. The overall accuracy was 92.4%. We conclude that US can be used as a first step in selecting patients for non-surgical therapy and if US indicates a contracted gall-bladder, 11% of the patients can be excluded from further diagnostic imaging.     

US in blunt abdominal trauma: need to be there 24 hours a day!

Purpose: To evaluate the utility of routine abdominal ultrasound (US) as first diagnostic imaging method 24 h a day in a series of patients admitted with blunt abdominal trauma to our level II trauma center. Methods: Two thousand four hundred and eleven consecutive patients admitted after blunt abdominal trauma over 12 months were prospectively evaluated using abdominal US. The examinations were performed within 25 min after admission. An experienced senior radiologist was available on site 24 h a day (including holidays) to perform all the US examinations. The US examination included a full abdominal exploration. The US results were compared to findings at computed tomography (n = 115), clinical follow-up (n = 2244), or surgery (n = 47). Results: Overall, 2411 US abdominal studies were performed. In 5/2411 (0.2 %) patients, the US examinations were incomplete or indeterminate because of patient obesity and were therefore excluded from the study. Of the remaining 2406 US studies, 265 (11 %) were performed between 0 and 6 a.m., 770 (32 %) were performed between 6 a.m. and 12 midday, 673 (28 %) were performed between 12 midday. and 6 p.m., and the remaining 698 (29 %) were performed between 6 and 12 p.m. At US, the following post-traumatic injuries were correctly detected: 67 splenic lesions, 62 liver injuries, 13 renal contusions, 2 bowel lacerations, and 1 pancreatic injury. Nineteen patients had a sonogram with negative findings followed by CT with positive findings, while 18 patients had a sonogram with positive findings followed by CT with negative findings. The following rates were calculated for the US studies: true negative = 2224; true positive = 145; false positive = 18; false negative = 19; sensitivity = 88.4 %; specificity = 99.2 %; diagnostic accuracy = 98.2 %; positive predictive index = 88.9 %; negative predictive index = 99.1 %. Conclusion: Abdominal US provides a highly accurate, noninvasive imaging evaluation in patients who have sustained blunt abdominal trauma. This can be obtained particularly if a team of senior radiologists can perform the examination to provide high quality sonograms and be on site 24 h a day.     

Incidental findings on trauma ultrasonography

Purpose: To determine the prevalence of incidental findings detected on the focused abdominal sonogram for trauma. Methods: From November 1996 to February 1998, 1914 radiologist-assisted trauma ultrasound examinations were performed. Incidental findings were tabulated by retrospective review of the trauma radiology daily logbooks. Results: Incidental nontraumatic findings were detected in 160 (8.36 %) of the acutely injured patients. Most findings were benign, including echogenic liver, renal cysts, and cholelithiasis. However, significant pathology was detected in several patients, including renal masses, hepatic metastases, and gynecologic disease. Conclusion: The radiologist-assisted trauma ultrasound examination can provide valuable diagnostic information beyond the detection of free fluid. This may have important implications, as nonradiologists are increasingly involved in the practice of trauma ultrasonography. Even in the setting of trauma, significant occult pathology can be detected on a targeted ultrasound examination.     

Clinical outcomes of naval aviation personnel with cholelithiasis

BACKGROUND: This study examines the aeromedical outcomes of aviation personnel with asymptomatic cholelithiasis or those treated successfully with conventional (open) cholecystectomy (CC), laparoscopic cholecystectomy (LC), or extracorporeal shock wave lithotripsy (ESWL) for previous symptomatic cholecystitis. METHODS: The Biomedical Database of the Naval Aerospace Medical Institute was searched for waiver requests for asymptomatic gallstones, acute cholecystitis, and cholecystectomy. Microfiche records were then reviewed. The rates of development of symptomatic disease and need for cholecystectomy or ESWL were noted in aircrew granted waivers for asymptomatic cholelithiasis. The aeromedical outcomes of aircrew who underwent treatment for symptomatic disease by cholecystectomy (CC or LC) or ESWL were reviewed. RESULTS: A search of the Biomedical Database revealed waiver requests for cholelithiasis for 79 naval aviation personnel from April 1988 to August 2000. Waiver requests were for previous cholecystectomy in 56 (70.9%) and cholelithiasis in 23 (29.1%). No aviators had undergone ESWL. Of the 56 aviators with previous cholecystectomy, waivers were granted in 51 (91.1%) cases. Waivers were denied to five individuals, primarily for other medical problems. Of the 23 aviators with cholelithiasis, 11 (47.8%) were granted waivers. Waivers were denied in 12 aviators because of symptomatic cholelithiasis (5), asymptomatic cholelithiasis (1), common bile duct stone (1), other medical problems (3), or no explanation (2). The aviator with asymptomatic cholelithiasis and two of the aviators with symptomatic cholelithiasis were subsequently granted waivers after cholecystectomy (LC). The aviator with a symptomatic common bile duct stone received a waiver after cholecystectomy (CC). A total of 66 (83.5%) aviators received waivers. None were revoked during the study period because of symptomatic cholelithiasis or retained common bile duct stones. CONCLUSIONS: Aviation personnel who receive waivers for asymptomatic cholelithiasis or cholecystectomy rarely present with symptomatic biliary disease.     

Accuracy of multidetector row computed tomography for the diagnosis of acute bowel ischemia in a non-selected study population

The diagnostic accuracy of multidetector row computed tomography for the prospective diagnosis of acute bowel ischemia in the daily clinical routine was analyzed. Two hundred ninety-one consecutive patients with an acute or subacute abdomen, examined by MDCT over a time period of 5 months, were included in the study. All original CT diagnoses made during the daily routine by radiological generalists were compared to the final diagnoses made by using all available medical information from endoscopies, surgical interventions, autopsies and follow-up. Finally, all CT examinations of patients with an initial CT diagnosis or a final diagnosis of bowel ischemia were reread by a radiologist specialized in abdominal imaging in order to analyze the CT findings and the reasons for initially false negative or false positive CT readings. Twenty-four patients out of 291 (8.2%) had acute bowel ischemia. The age of affected patients ranged from 50 to 94 years (mean age: 75.7 years). Eleven patients were male, and 13 female. Reasons for acute bowel ischemia were: arterio-occlusive (n=11), non-occlusive (n=5), strangulation (n=2), over-distension (n=3) and radiation (n=3). The prospective sensitivity, specificity, PPV and NPV of MDCT for the diagnosis of acute bowel ischemia in the daily routine were 79.17, 98.51, 90.48 and 98.15%. MDCT reaches a similarly high sensitivity in diagnosing acute bowel as angiography. Furthermore, it has the advantage of being helpful in most of its clinical differential diagnoses and of being less invasive with the consecutive possibility of being used earlier in the diagnostic process with all the resulting positive effects on the patients prognosis. Therefore, nowadays MDCT should probably be used as the first step imaging modality of choice in patients with suspected acute bowel ischemia.     

Computed tomography of the gallbladder.

Computed tomography (CT) was used to study 79 patients with suspected gallbladder disease. First and second generation scanners were used to determine the efficacy of CT in detecting cholecystitis or cholelithiasis. Manifestations of gallbladder disease such as hydrops, opaque and nonopaque gallstones, chronic cholecystitis with thickened inflammatory walls, and secondary liver abscesses can be easily detected. It is a useful technique for individuals in whom the gallbladder has failed to opacity on oral cholecystography. The scanning method is described, and estimates of reliability are given including its accuracy, limitations, and place in the management of gallbladder disease, especially cholelithiasis. When conventional radiographic examinations or ultrasound fail to give definitive diagnostic information, CT can be a useful alternative with an overall diagnostic accuracy greater than 80%.     

Pediatric emergency gastrointestinal ultrasonography: pearls & pitfalls

Ultrasonography is an essential tool in pediatric imaging, particularly in the emergency setting. Although ultrasound is often the favored initial modality for abdominal imaging in children, it is highly operator-dependent and therefore prone to misinterpretation which can lead to false positive or negative exams, or even incorrect diagnoses. Conditions discussed in this series include ileocolic intussusception, hypertrophic pyloric stenosis, appendicitis, and ingested foreign bodies. We will review diagnostic criteria, highlight crucial findings, and illustrate commonly-encountered difficulties and mimics.     

Ultrasound mammography.

Ultrasound mammography was performed with unique, high resolution equipment which displays changes in acoustic properties of tissues through a calibrated gray scale. Color-coded isodensitometry was used to assist in the differential diagnosis. The rate of agreement between the ultrasound and pathological diagnoses was 86.7%. The false negative and false positive rates were 7.6% and 18.5%, respectively. Three problems must be solved before ultrasound mammography can be used as a screening device: First, additional clinical data must be accumulated. Second, the number of ultrasonograms needed for diagnosis must be reduced. Third, special equipment designed for ultrasound mammography must be developed.     

Accuracy of radiographer preliminary clinical evaluation of skeletal trauma radiographs,in clinical practice at a district general hospital

IntroductionError in interpretation of trauma radiographs by referrers is a problem which has detrimental effects on the patient and causes unnecessary repeat attendances. Radiographers can reduce errors by offering their opinion at the time of imaging. The Society and College of Radiographers have a longstanding recommendation that Red Dot (RD) schemes should be replaced by Preliminary Clinical Evaluation (PCE). The purpose of the study was to evaluate radiographer interpretation of skeletal trauma radiographs in clinical practice, determine if there was any difference in ability to interpret appendicular and axial studies, and evaluate appropriateness of PCE implementation.MethodsA convenience sample of 23 self-selecting radiographers provided RD and PCE on 762 examinations. Each case was compared against the verified report and assigned a true negative/positive or false negative/positive value. Accuracy, sensitivity and specificity were calculated and performance measures between RD versus PCE, and appendicular versus axial were compared using Two-sample Z-Tests. Error analysis was performed and inter-observer consistency determined.ResultsOverall RD and PCE accuracy, sensitivity and specificity for the study were 90%, 72% and 97% (RD), and 92%, 80% and 97% (PCE) respectively. Significant difference was demonstrated for sensitivity with PCE more sensitive than RD (p-value 0.03) and appendicular more sensitive than axial (RD p-value <0.02, PCE p-value <0.0001). Most errors were false negatives. Inter-observer consistency was evaluated by review of 128 cases and no difference between reviewers was established.ConclusionRadiographers without specific training were able to provide RD and PCE to a high standard. Radiographers interpreted positive findings more accurately using PCE than RD, and positive findings on appendicular cases were interpreted more accurately than those on axial cases.Implications for practiceThis study supports local PCE implementation, contributes to the wider evidence base to justify transition towards PCE and identifies the necessity for local axial image interpretation training.     

General practitioner requests for upper abdominal ultrasound: their effect on clinical outcome

Many radiology departments offer direct access upper abdominal ultrasound (US) scanning to general practitioners (GPs). We aimed to examine the influence of the scan results on the subsequent management and clinical outcome of these patients. A retrospective review was performed on all the patients referred for primary upper abdominal US (n = 82) from a single Birmingham GP practice, of 10,000 patients, between 1991 and 1996. The follow-up period from US was mean 27.9 months, SD 18.2 months. 79 referrals complied with published guidelines. 77 referrals were for suspected gallstone disease. 23 (28%) patients had clinically relevant positive findings. 18 of the positive scans. 16 of whom had gallstones, were subsequently referred to hospital. Of those with gallstones, 15 underwent cholecystectomy, of whom 12 had no further upper abdominal symptoms. Of the 59 negative scans, eight cases (14%) were subsequently referred to hospital. Treatment was changed as a result of review and investigation in only two of these eight cases. The remaining 51 were diagnosed solely on history and clinical examination. 28 of the 51 had self-limiting symptoms which required minor or no treatment. In conclusion, direct access upper abdominal US is considerably reducing the requirement for hospital outpatient referrals from GPs. Positive scans are generally followed by referral to secondary care services with good clinical outcome.