Female patients with acute lower abdominal or pelvic pain often represent a diagnostic challenge. The differential diagnosis is broad (Table 16-1), and the workup often requires multiple diagnostic tests. Ultrasound is the initial diagnostic imaging modality of choice in the majority of cases. Point-of-care ultrasound, performed and interpreted by the clinician, and completed at the time of the initial physical examination, helps narrow the differential diagnosis and may eliminate the need for further diagnostic testing.
Table 16–1. Differential Diagnosis of Lower Abdominal Pain in Female Patients ||Download (.pdf)
Table 16–1. Differential Diagnosis of Lower Abdominal Pain in Female Patients
Inflammatory bowel disease
Irritable bowel syndrome
Pelvic inflammatory disease
Hemorrhagic functional cysts
Imaging the pelvis is a crucial step in the evaluation of women with lower abdominal pain or pelvic pain. Accurate management is predicated on choosing the most effective diagnostic tool. Four diagnostic modalities are available for evaluating the pelvis: ultrasound, CT, MRI, and laparoscopy.
Ultrasound has proven to be a rapid, noninvasive, portable, repeatable, inexpensive, and accurate method for visualizing and diagnosing pathology within the pelvis. Several advantages over CT, MRI, and even the bimanual pelvic examination have made ultrasound the first-line diagnostic imaging modality in patients with acute pelvic pain or masses.1–3 Both transabdominal and endovaginal ultrasound can be used by the clinician at the bedside during the initial physical examination. The use of point-of-care ultrasound has far-reaching benefits to patient care. It may identify specific diseases in the differential diagnosis and often eliminates the need for expensive and time-consuming diagnostic tests (Figure 16-1). In addition, ultrasound does not expose patients to ionizing radiation. Since the clinician performs the point-of-care ultrasound examination, patients perceive this as more time spent with their physician. This serves to improve patient satisfaction, provides them with more time to ask questions, and ultimately increases their confidence in the physician and their understanding of the diagnosis. Another advantage unique to ultrasound is the ability of color flow Doppler to evaluate pelvic organs for adequacy of blood flow.
The top image refers to the transverse placement of a large footprint curved array transducer. The bottom image depicts a complex ovarian mass, one of the many entities that lies within the differential diagnosis for women presenting with acute pelvic pain.
The main disadvantage of ultrasound with respect to the other imaging modalities is its limited scope. Other imaging modalities, such as CT and MRI, may yield valuable information about other organ system pathology and the extent to which a disease process may have progressed. Also, sonograms are sometimes technically inadequate due to interference from bowel gas.