Most Appropriate Next Imaging Step
Combined transvaginal and transabdominal ultrasound with Doppler is the most appropriate initial imaging modality for an elderly woman with three weeks of abdominal pressure and pelvic pain following pelvic examination. 1, 2
Rationale for Ultrasound as First-Line Imaging
The American College of Radiology explicitly designates pelvic ultrasound using a combined transabdominal and transvaginal approach as the initial imaging study of choice for postmenopausal subacute or chronic pelvic pain localized to the deep pelvis. 1
This combined approach provides both the anatomic overview from transabdominal imaging and the superior spatial and contrast resolution from transvaginal imaging, which are complementary techniques that should be performed together as a single comprehensive examination. 1, 2
Doppler evaluation (both color and spectral) is considered a standard component of pelvic sonography and should be included routinely to evaluate internal vascularity, distinguish fluid from soft tissue, and assess for pelvic venous disorders. 1, 2
What Ultrasound Can Detect in This Clinical Scenario
Ultrasound provides anatomic information about uterine size, endometrial canal distension, fallopian tube dilation, ovaries, and adnexal masses—all critical in evaluating subacute pelvic pain in elderly women. 1
In postmenopausal women specifically, transvaginal sonography can detect endometrial changes including carcinoma or hyperplasia with 81% sensitivity, and ovarian pathology with 83% sensitivity and 100% specificity. 3
Chronic pelvic inflammatory disease manifestations including pelvic fluid, hydrosalpinx, pyosalpinx, inflammatory adnexal masses, and peritoneal inclusions are visible by ultrasound. 1
Real-time dynamic ultrasound can document abnormal adherence or lack of mobility of structures when pelvic adhesions are suspected, though adhesive disease remains notoriously difficult to confirm nonoperatively. 1
Why Not CT or MRI Initially
CT abdomen and pelvis has no established role as a primary imaging modality for chronic pelvic pain, though it may be useful as second-line imaging after equivocal ultrasound or when pain is poorly localized with a broad differential diagnosis. 2
Plain radiography has no evidence supporting its use to evaluate postmenopausal subacute or chronic pelvic pain localized to the deep pelvis. 1
MRI pelvis is recommended as the problem-solving examination of choice when ultrasound findings are nondiagnostic or inconclusive, not as initial imaging. 2
Critical Pitfall to Avoid
If the etiology of pelvic pain remains obscure after CT (if performed first), subsequent ultrasound has the capacity to provide additional information about the adnexa in particular—this highlights why ultrasound should be performed first rather than skipped. 1
In postmenopausal women with pelvic pain, cancer must be considered in the differential diagnosis, making comprehensive imaging evaluation essential rather than optional. 4
Special Considerations for Elderly Women
Small postmenopausal cysts (≤5 cm diameter) have low incidence of malignancy and can be followed by transvaginal ultrasound without immediate surgical intervention if they appear simple. 3
For women over age 70, inspection of the vulva, perineum, and anus should be considered to identify benign or malignant disease that may be unrecognized by this population. 5