Evaluation of sacroiliac joint MRI for pelvic venous congestion signs in women clinically suspected of sacroiliitis

Acute pelvic pain: A pictorial review with magnetic resonance imaging

Acute uterine emergencies constitute both obstetric and gynecologic conditions. The superior image resolution, superior soft-tissue characterization, and lack of ionizing radiation make magnetic resonance imaging (MRI) preferable over ultrasonography (USG) and computed tomography (CT) in investigating uterine emergencies. Although USG is the first-line imaging modality and is easily accessible, it has limitations. USG is an operator dependent and limited by patient factors such as obesity and muscle atrophy. CT is limited by its risk of teratogenicity in pregnant females, poor tissue differentiation, and radiation effect. The non-specific findings on CT may lead to misinterpretation of the pathology. MRI overcomes all these limitations and is emerging as the most crucial imaging modality in the emergency room (ER). The evolving 3D MR sequences further reduce the acquisition times, expanding its ER role. Although MRI is not the first-line imaging modality, it is a problem-solving tool when the ultrasound and CT are inconclusive. This pictorial review discusses the various MRI techniques used in uterine imaging and the appearances of distinct etiologies of uterine emergencies across different MRI sequences.

Frequency of potential causes of lower back pain and incidental findings in patients with suspected sacroiliitis: retrospective analysis of 886 patients with negative sacroiliac MRI examination for sacroiliitis

BACKGROUND

In a majority of patients with suspected sacroiliitis (SI) who underwent sacroiliac magnetic resonance imaging (MRI), imaging studies may be normal, may depict other causes for pain, or may show clinically irrelevant incidental findings.

PURPOSE

To determine the prevalence of possible etiologies other than SI and frequency of incidental findings demonstrated on sacroiliac MRI examinations in a cohort of patients with lower back pain and suspected SI.

MATERIAL AND METHODS

Sacroiliac MRI examinations of 1421 patients with suspected SI were retrospectively reviewed. In patients without SI findings, other potential causes for lower back pain and incidental findings were documented.

RESULTS

SI was present in 535 of 1421 patients (37.6%). In 886 of the patients whose MRI studies were negative for SI, other possible causes for lower back pain or incidental findings were seen in 386 (43.5%). The most common musculoskeletal (MSK) finding was lumbosacral transitional vertebra (8.6%) followed by findings suggesting piriformis syndrome (4.2%), spondylosis (3.7%), and sacral insufficiency fractures (1.8%). The most common non-MSK findings were follicular cysts (15.3%) and uterine fibroids (4.9%).

CONCLUSION

In patients with suspected SI but negative MRI examinations for SI, some other possible causes for lower back pain and several incidental findings can be seen on imaging. The presence of these findings may explain the patient's symptoms, and awareness of these conditions may be helpful in patient management and individualizing treatment.

Increased prevalence of pelvic venous congestion sign on sacroiliac MRI in women with clinically suspected sacroiliitis

OBJECTIVE:

To compare the prevalence of pelvic venous congestion (PVC) sign on sacroiliac and hip MRI in women of reproductive age as a possible cause of pain mimicking sacroiliitis.

METHODS:

This retrospective study included 727 MRI examinations (401 sacroiliac joint MRI and 326 hip joint MRI) that were performed between January 2010 and December 2017. Images were evaluated for the presence of sacroiliitis, presence of PVC sign and presence of other incidental findings of musculoskeletal and genitourinary disorders. After removing patients with other musculoskeletal and genitourinary disorders that may cause pain (n=188), remaining 539 (322 sacroiliac and 217 hip), MRI examinations were re-analyzed for the presence of PVC sign.

RESULTS:

Four hundred one patients with sacroiliac MRI examination had 120 (29.9%) PVC sign and 326 patients with hip MRI examinations had 54 (16.6%) PVC sign (p<0.001). After removing patients with other musculoskeletal and genitourinary disorders that may cause pain, 322 patients with sacroiliac MRI had 102 (31.7%) PVC sign and 217 patients with hip MRI examinations had 38 (17.5%) PVC sign (p<0.001). No significant difference was found between patients with acute sacroiliitis and patients without acute sacroiliitis concerning PVC prevalence (p>0.05). There were also no significant differences between other comparable incidental findings.

CONCLUSION:

Significantly increased PVC prevalence in sacroiliac MRI exams may be attributable to PCS simulating clinical sacroiliitis.