Prospective study of digital radiographs versus conventional screen films in Small Bowel Follow-Through examination.

PURPOSE: To prospectively compare subjective radiological quality, radiation dose and effect on workflow using digital radiography (DR) vs. conventional screen film (SF) radiography in the Small Bowel Follow-Through (SBFT) examination. METHODS: Five attending and four resident radiologists compared hard-copy images from 11 SBFT examinations, for which every patient had a defined pair of SF and DR images taken 20-30 min apart. SF and DR were performed with equivalent exposure data. Overall image quality, intestinal mucosa definition and bone visualization were graded on a 5-point scale, with 5 being the highest value. Thus, 11 patients had three criteria judged by nine observers in two modalities for a total of 594 observations of image quality. The radiation doses and effect on workflow were also compared. Statistical analysis was performed with the Mann-Whitney U test. RESULTS: The mean scores on DR and SF for overall image quality, intestinal mucosa definition and bone visualization were 4.49 vs. 3.17, 4.38 vs. 3.4, and 4.5 vs. 2.4, respectively (p<0.001 in all cases). The average radiation dose with DR was 0.93+/-0.54 cGy, and -1.58+/-0.63 cGy with SF (p=0.016), reflecting a 41% dose reduction. Production of a DR image by technicians took 3.5+/-1.3 min vs. 5.5+/-1.5 min for SF (p=0.002). CONCLUSION: Subjective image quality of hard-copy digital radiographs of the small bowel through examination is superior to images obtained with conventional radiographs, with an associated reduction of 41% in radiation dose and increased efficiency.

24-Hour/4-hour ratio of technetium-99m methylene diphosphonate uptake in patients with bone metastases and degenerative bone changes.

The uptake of [99mTc]MDP in metastatic lesions of the vertebrae was compared with the uptake in normal vertebrae. The ratio of these lesion-to-nonlesion uptakes at 4 and 24 hr was called the 24-hr/4-hr ratio (TF ratio). A similar ratio was measured for lesions in the spine due to degenerative bone disease. Lesions in vertebrae with degenerative bone disease and treated metastases had a significantly lower TF ratio than lesions in vertebrae with untreated bone metastases. These findings suggest that the TF ratio might be a reliable method for separating metastatic lesions from degenerative changes in the vertebral column, and could be especially useful in cancer patients whose bone scans demonstrate a single lesion in the spine.

Residual mass and negative gallium scintigraphy in treated lymphoma.

Two patients with treated lymphoma demonstrated a residual mass on CT following treatment. In both cases gallium-67 (67Ga) scintigraphy demonstrated increased uptake in the original tumor mass and no uptake in the mass after treatment. In both cases the entire residual tumor mass was resected and found to contain no cancer tissue. This is further evidence of the role 67Ga scintigraphy may play in monitoring response of lymphoma patients to treatment. In contrast, other imaging modalities such as ultrasound, plain film x-rays, or CT only show the presence of a mass but not its nature.

Early detection of lymphoma recurrence with gallium-67 scintigraphy.

Early detection of tumor relapse in lymphoma patients is often a difficult diagnostic problem. CT, which detects a mass, often cannot differentiate between fibrosis or relapsed tumor. For this reason, we have studied the value of 67Ga scintigraphy in the diagnosis of tumor recurrence. The sensitivity of 67Ga scintigraphy in the detection of lymphoma recurrence was studied at an average interval of 8.7 mo following treatment in 32 patients who developed recurrent lymphoma. Its specificity was studied in 36 patients with no recurrence who were in continuous clinical remission. At the time of appearance of relapse, the sensitivity of whole-body 67Ga imaging was 95% and the specificity 89%. In 12 events of recurrence in 10 patients, 67Ga scintigraphy was abnormal at sites that later proved to be regions of relapse. In these patients, scintigraphy demonstrated recurrence an average of 6.8 mo before the appearance of clinical symptoms, findings on clinical examination or abnormality on CT or chest x-rays. Gallium-67 scintigraphy, which permits screening of the whole body for recurrence in a single study, was of particular value in evaluating lymphoma recurrence, since 27% of the recurrences were located exclusively in sites different from the original sites of disease. Gallium-67 scintigraphy appears to be a sensitive and specific test for restaging patients with lymphoma recurrence.

Preoperative diagnosis of Mirizzi syndrome.

Mirizzi syndrome is defined as an obstruction of the common hepatic duct by a stone present in the cystic duct or neck of the gallbladder. This entity rarely has been reported, and in only a few cases was the diagnosis made preoperatively. The preoperative diagnosis is of great importance since intraoperative findings may be similar to carcinoma of the extrahepatic biliary system, which requires a different technical approach. Furthermore, unrecognized cholecystobiliary or cholecystoenteric fistula resulting from stone penetration lead to serious postoperative complications, which can be avoided if the condition is properly recognized.

Computed tomography of Crohn's disease--reevaluation.

The indications and CT features of Crohn's disease were reevaluated, based on 48 examinations in 28 patients. Although CT is indicated mostly in the complications of Crohn's disease, it played a major role in the primary diagnosis of Crohn's disease in 8 patients. 5 unsuspected patients had CT for other abdominal indications and 3 had the examinations as part of an elective diagnostic work-up. The following CT features of Crohn's disease are worthy of note: Bowel wall thickening is usually obvious and needs no measurement. Abscesses are often of inhomogeneous density and should be differentiated from inflammatory bowel conglomerates. Late CT scans can be helpful in this respect. Fistulae are not well demonstrated directly by CT. The fistulogram remains the examination of choice, when possible. Mesenteric lymphadenopathy is small and discrete. Mesenteric lipomatosis can be massive and is often a cause of bowel separations and mass effect.

The use of endotracheal tubes to assist in manipulation of esophageal strictures, in elongation of the esophagus in esophageal atresia, and in gastrojejunal feeding tube placement.

Because of the special qualities of a PVC endotracheal tube (smooth, soft, pliable but still with a patent lumen), it serves very well for the intubation of the esophagus or the duodenum through an established gastrostomy. In this article the use of endotracheal tubes in different manipulations of the esophagus and gastroduodenum is described.

Osteomyelitis of the femoral neck caused by a pencil stab wound.

A unique case of osteomyelitis of the femoral neck of an eleven-year-old boy, following a stab wound by a lead pencil, with reactive synovitis of the hip joint is presented. The clinical course simulated that of acute septic arthritis and was diagnosed by various imaging modalities. Following operation and systemic antibiotic treatment, the patient improved dramatically. The role of sonography in the presence of inflammatory conditions around the hip joint is emphasized.

Bone Browser a decision-aid for the radiological diagnosis of bone tumors.

Bone Browser, a decision-aid for radiological diagnosis of bone tumors, was developed in cooperation with the Radiology Department of the Rambam Medical Center, Haifa. The system offers case specific advice from an expert system (ES), general information on the lesion area and allows for recording and retrieving cases. The ES utilizes both rule-based and probabilistic inferencing methodologies to arrive at a differential diagnosis (DD). The knowledge base was validated on 105 cases with known outcome. Clinical evaluation consisted of 59 new cases whose final diagnosis was not known to the evaluators. The correct diagnosis was included in the system's DD in 85% of the cases, which is comparable to the diagnostic accuracy of senior radiologists (88%). The system proved to be helpful to the expert, diagnosing cases missed by the radiologists and suggesting additional diagnoses not listed by the radiologists, raising their diagnostic capability to 91%.

Computed tomography in the preoperative evaluation of gastric carcinoma.

Computed tomography (CT) of the abdomen was done in 49 patients with gastric carcinoma. These cases were retrospectively staged and evaluated as to operability. Various staging parameters were also evaluated separately. The results were correlated to findings on surgery, liver scan, and cytology. Overall accuracy of CT staging and operability assessment was 72 and 82%, respectively. Among the various CT parameters, perigastric fat invasion had a positive predictive value of 91%. The demonstration of local node involvement and invasion of adjacent organs was unreliable. Since surgery is currently the only treatment for gastric carcinoma, CT staging has limited clinical value. The principal role of CT is in the assessment of operability in patients with carcinoma of the stomach.

Rectosigmoid pseudostenosis due to urinary retention.

Pseudostenosis of the rectosigmoid colon due to compression by a dilated urinary bladder may pose a diagnostic problem. Although probably quite common, it has not received much attention in the radiological literature. Four cases are presented and the radiological features on barium enema are described.

Computed tomography-guided percutaneous drainage of right upper abdominal abscesses.

Definitive computed tomography-guided percutaneous drainage of right upper abdominal abscesses was performed in eight patients (11 procedures). A lateral perpendicular approach was used in all cases. An Argyl trocar catheter was used in nine procedures and a pigtail catheter in two. The drainage was successful in seven patients. In one patient no drainable abscess was found. Percutaneous abdominal abscess drainage should be considered a satisfactory alternative to surgical drainage in poor-risk patients as well as in patients who have had repeated operations in whom any further surgery may be unduly difficult.

Cortical bone loss in triamcinolone-treated mice.

Immature mice were treated for up to 8 weeks with daily doses of triamcinolone diacetate. The humerus was studied radiographically at regular intervals. Roentgenographic measurements included midshaft width, medullary width, cortical thickness and total length. By the time of the tenth injection significant cortical bone loss was noted, followed by increased width of the medullary cavity and osteoporosis. An initial phase of active endosteal bone resorption was replaced by a prolonged steady state which extended throughout the experimental period. Possible explanations for the above findings are discussed.