No abstract

Thallium-201 myocardial perfusion scintigraphy is reported to be a less accurate diagnostic test for coronary artery disease in women than in men. We retrospectively analyzed 34 Tl-201 studies obtained in 28 symptomatic women and compared them with those obtained in 32 men during the same interval. Three criteria were tested: criterion 1 was defined as abnormal scans showing any defect; criterion 2, scans showing only transient (reversible) defects; and criterion 3, scans showing either transient or "significant" (i.e., not due to breast attenuation) fixed defects. The sensitivity in women was 1.00, 0.73, and 0.93, respectively; the specificity, 0.26, 0.84, and 0.85. The best values in men were a sensitivity of 1.00 and a specificity of 0.86. The three criteria were then prospectively tested in 33 scans of 29 additional women. The sensitivity was 0.90, 0.65, and 0.80, respectively, and the specificity, 0.18, 1.00, and 0.92. Defects (usually fixed) due to breast attenuation artifact were seen frequently (30%). Criterion 3 best differentiates such defects from those resulting from coronary artery disease, making Tl-201 myocardial perfusion scintigraphy as accurate in women as in men.

We prospectively evaluated 38 adult patients with chronic constipation with and without defecatory difficulties using a newly described scintigraphic test to measure rectal emptying and compared them to 20 healthy controls. All patients underwent anorectal manometry, and 30 who complained of infrequent defecation underwent a colonic transit study using radiopaque markers. Control subjects promptly evacuated both 100 ml and 200 ml artificial stool in a characteristic fashion, but three evacuated none of the 100-ml volume and two had no evacuation of the 200-ml stool (inhibited controls). Constipated patients exhibited three patterns of emptying: (1) normal emptying of both volumes (47%); (2) poor emptying of both volumes or inhibited defecation (29%); and (3) normal emptying of the 200-ml but abnormal evacuation of the 100-ml volume (24%). An abnormal expulsion pattern during manometry occurred in 21% of patients and was strongly associated with the inhibited defecation pattern. However, defecation patterns could not be predicted on the basis of age, gender, symptoms, duration of complaints, colonic transit, or other rectal manometric parameters. Although rectal scintigraphy has potential advantages as a diagnostic test in terms of quantitation and decreased radiation exposure, the inability of the test to distinguish patients with slow transit constipation and defecatory complaints makes the potential utility of this test of uncertain value in clinical and investigative settings.