Transvaginal US vs. CT in non-pregnant premenopausal women presenting to the ED: clinical impact of the second examination when both are performed

Abstract

Objective: To determine the clinical impact of the second examination when both CT and TVUS are obtained in the same ED visit for acute pelvic/lower abdominal symptoms in non-pregnant premenopausal women.

Methods: 200 consecutive non-pregnant premenopausal women (mean age, 31.8 years; range, 18-49 years) who underwent both ED-based TVUS and abdominopelvic CT evaluation for acute symptoms over a 12 month period were included; 107 women had TVUS first, followed by CT; 93 women had CT first. All relevant clinical, radiologic, and pathologic findings were reviewed to establish a final diagnosis. Any additional clinical impact provided by the second imaging test was assessed by two experienced abdominal radiologists.

Results: Initial TVUS was interpreted as normal (n = 63) or mentioned incidental findings (n = 11) in 69% (74/107); subsequent CT established a non-gynecologic GI/GU etiology in 25 (34%). For 37% (34/93) of CT exams interpreted as normal, TVUS added no new information. In 32 cases (34%), TVUS further excluded ovarian torsion/adnexal pathology when initial CT was indeterminate/equivocal. Overall, CT following TVUS provided a key new or alternative diagnosis in 26% (28/107), whereas TVUS after CT provided a relevant new/alternative diagnosis in only 1/93 cases (p < 0.001). In nine cases (8%), CT confirmed a positive US diagnosis but detected relevant additional diagnostic information.

Conclusion: CT following negative TVUS frequently identified a non-gynecologic cause of acute pelvic or lower abdominal symptoms in non-pregnant premenopausal women, whereas the main benefit of TVUS after CT was more confident exclusion of ovarian torsion.

Keywords: Computed tomography; Non-traumatic abdominal pain; Nonpregnant; Premenopausal; Ultrasound.

Fig. 1

47-year-old female who presented with right lower quadrant pain. Initial TVUS (not shown) was interpreted as normal, but CT demonstrated a dilated, fluid-filled, thick-walled enhancing appendix with appendicolith, compatible with acute uncomplicated appendicitis

Fig. 2

19-year-old female who presented to the ED with right lower quadrant abdominal pain. Pelvic US (transabdominal/transvaginal approach per protocol) was initially performed to assess for ovarian torsion or tubo-ovarian abscess. US was read as normal; a survey gray-scale transabdominal image of the right kidney is shown (A). Transvaginal images obtained (not shown) were also read as normal. Subsequent axial (B) and coronal (C) contrast-enhanced CT images demonstrate peripheral wedge-shaped low attenuation involving the upper pole parenchyma of the right kidney, compatible with uncomplicated pyelonephritis, which was confirmed at urinalysis

Fig. 3

35-year-old female with surgical history of gastric bypass presenting with abdominal pain. Initial TVUS (not shown) was interpreted as normal. Coronal contrast-enhanced CT demonstrates a radial configuration of congested small bowel loops in the left upper quadrant with prominent mesenteric edema in a configuration concerning for internal hernia, which was confirmed at surgery

Fig. 4

28-year-old-female presented with right-sided abdominal pain. Transabdominal image from initial TVUS (A) demonstrates moderate right-sided hydronephrosis. Subsequent CT confirmed this, but also demonstrated right renal enlargement and delayed nephrogram (B), with obstructing 3-mm stone identified at the right ureterovesicle junction (C). The calculus was not identified at TVUS

Fig. 5

29-year-old female who presented with right lower quadrant pain. Coronal contrast-enhanced CT (A) demonstrates an enlarged and medialized right ovary containing a large, complex fat-containing mass, compatible with dermoid. Prominent congested vascular pedicle is present (arrow) but was not prospectively described. TVUS confirmed dermoid but showed presence of arterial and venous flow on pulsed Doppler (B). Torsion was found at surgery and surgical pathology demonstrated an infarcted dermoid (mature teratoma)

Fig. 6

40-year-old female who presented with right lower quadrant pain. CT (A) demonstrates two adjacent or single-bilobed cystic lesion involving the right ovary, which was enlarged and medialized, making torsion a leading concern. Subsequent TVUS showed presence of color Doppler flow (B) and lacy internal reticular echoes in one of the cysts, compatible with hemorrhage/retracting clot (C), making torsion less likely, and raising the possibility of the hemorrhagic cyst as the source of pain

Fig. 7

34-year-old female who presented with bilateral lower quadrant pain. Sagittal (A) and axial (B) CT demonstrates subtle peritoneal thickening in the pelvis, with mild associated inflammatory stranding (arrows), raising concern for PID. Subsequent TVUS (not shown) was interpreted as normal. Cervical cultures subsequently grew Neisseria gonorrhoeae