Upper gastrointestinal obstruction (UGIO), obstruction occurring at the level of the stomach or duodenum, represents only about 5% of bowel obstructions. As with other bowel obstructions, timely diagn Show more
Upper gastrointestinal obstruction (UGIO), obstruction occurring at the level of the stomach or duodenum, represents only about 5% of bowel obstructions. As with other bowel obstructions, timely diagnosis is necessary to prevent complications including ischemia and death. Because the presenting symptoms of UGIO can be vague and nonspecific, the diagnosis may not be suspected clinically. The radiologist therefore provides immense value as the diagnosis and often the etiology of the obstruction can be ascertained through imaging. Here we present a simple classification scheme of etiologies of UGIO into congenital, malignant, infectious/inflammatory, and mechanical categories, and provide examples of the most common and some uncommon causes for each category. We highlight that several of the congenital etiologies of UGIO can present at any age, including adulthood, and therefore it is important for the radiologist to keep these diagnoses in mind when reviewing cases of UGIO. For each etiology, we provide typical imaging strategies that are used for diagnosis as well as key points regarding the diagnosis. Show less
Although ultrasound is the primary modality used in the diagnosis of ectopic pregnancy, various forms of this condition and their complications may occasionally be further evaluated with MRI or may be Show more
Although ultrasound is the primary modality used in the diagnosis of ectopic pregnancy, various forms of this condition and their complications may occasionally be further evaluated with MRI or may be incidentally detected on CT or MRI when an alternative diagnosis is suspected. Various types of ectopic pregnancy have characteristic imaging features. Radiologists should be familiar with these features and should always consider the possibility of ectopic pregnancy in the setting of hemoperitoneum or a pelvic mass in a woman of child-bearing age. Familiarity with the typical CT and MRI appearances of various forms of ectopic pregnancy facilitates prompt and accurate diagnosis and treatment. Show less
To determine the feasibility of using gadoxetate disodium for MR urography. We retrospectively reviewed 50 consecutive gadoxetate disodium-enhanced abdominal MRI examinations meeting inclusion criteri Show more
To determine the feasibility of using gadoxetate disodium for MR urography. We retrospectively reviewed 50 consecutive gadoxetate disodium-enhanced abdominal MRI examinations meeting inclusion criteria. For each examination, 30 min postcontrast hepatobiliary phase sequences were reviewed to assess bilateral collecting system segments, including upper pole, interpolar, and lower pole calyces; renal pelvis; and proximal one-third of ureter. Each segment was assessed for degree of opacification (none, <50%, ≥50%, complete) and susceptibility artifact (none, partial thin rim, thick/complete rim, total obscuration). Opacification and susceptibility scores were also calculated for each examination. The 50 reviewed examinations were performed on 46 patients (26 women, 20 men; mean age, 57 years) and included a total of 1000 segments. Of these, 808 (80.8%) were opacified completely, 103 (10.3%) were opacified ≥50%, 39 (3.9%) were opacified <50%, and 50 (5.0%) were not opacified. Of 1000 segments, no susceptibility artifact was present in 822 (82.2%), while a partial thin rim was present in 113 (11.3%), a thick/complete rim in 64 (6.4%) and total obscuration in 1 (0.1%). Gadoxetate disodium contrast produced a high degree of opacification of the proximal urinary collecting system with low incidence of susceptibility artifact; therefore, it is a feasible contrast agent for MR urography. Show less