Shella Farooki

Posterior tibialis tendon tears

Gerling MC, Pfirrmann CA, Farooki S, et al. Posterior tibialis tendon tears: Comparison of the diagnostic efficacy of magnetic resonance imaging and ultrasonography for the detection of surgically created longitudinal tears in cadavers. Invest Radiol 2003;38:51–56. Rationale and Objectives.The optimal advanced imaging method for detection and characterization of posterior tibialis tendon (PTT) tears is unclear. The purpose of this study was to investigate the utility of ultrasonography (US) and MR imaging in the detection of surgically created PTT tears in cadavers. Materials and Methods.This was a prospective blinded study in which 16 fresh cadaveric foot and ankle specimens (3 men, 13 women; average age at death 83.9 years; age range 71–96 years) were scanned with both US and MR imaging before and after the surgical creation of 64 variable length longitudinal tears of the PTT. Ultrasonography was performed with a 12 MHz linear transducer with independent interpretations of static and dynamic studies separately by two blinded and experienced musculoskeletal radiologists. MR imaging was performed at 1.5 T with a standard transmit-receive extremity coil using axial, sagittal, coronal T1-weighted (TR 600, TE 20), and axial fast spin echo proton density and T2-weighted (TR 3000, TE 161/20, ETL 12) images. MR images were reviewed independently by two experienced musculoskeletal radiologists who were blinded to the status of the PTT. Results.Sensitivity, specificity, and accuracy of MR imaging in the diagnosis of PTT tears were 73%, 69%, and 72%, respectively. Dynamic US interpretation yielded values of 69% sensitivity, 81% specificity, and 72% accuracy. Static US interpretation was less reliable than dynamic interpretation, and the only significance of static imaging was a high specificity (94%) for detection of longitudinal tears. The positive predictive value (PPV) for MR imaging and US was 88% and 92% respectively, and the negative predictive value (NPV) was 46% for both MR imaging and US. Conclusion.Our results suggest that US and MR imaging perform at the same level for the detection of surgically created longitudinal PTT tears in a cadaveric model. US has a higher specificity compared with MR imaging.

Magnetic resonance imaging of septic arthritis

Septic arthritis is a disabling and life-threatening disease that requires early diagnosis for optimal outcome. Although traditionally a clinical and laboratory diagnosis, some patients may be misdiagnosed and referred for magnetic resonance (MR) imaging. Therefore, radiologists need to be aware of the MR imaging findings of septic arthritis, its complications, and diagnostic pitfalls.

In vivo high resolution coronal MRI of the wrist at 8.0 tesla.

The wrists of asymptomatic volunteers were imaged at 8 and 1.5 T. The signal-to-noise ratio, spatial resolution, and soft tissue contrast of the 8 T images were much greater. The increased signal-to-noise ratio available at 8 T allows acquisition of high quality, high resolution images and visualization of intricate anatomy at scan times acceptable for clinical imaging.

MRI of the medial and lateral plantar nerves.

Purpose The purpose of this work was to demonstrate nerve anatomy of the medial plantar (MP) and lateral plantar (LP) nerves and the first branch of the lateral plantar (FBLP) nerve as depicted with MRI. Method High resolution MRI of the heel was performed with a standard transmit-receive extremity coil in six human cadaveric specimens using sagittal, axial, and coronal T1-weighted spin echo images. The specimens were then sectioned in the axial and coronal planes. Results MRI depicted the MP and LP nerves arising from the posterior tibial (PT) nerve. Assessment of the anatomic course and trifurcation of the PT nerve into the plantar nerves and the FBLP nerve was best seen in the sagittal plane. Various portions of these nerves were visualized also in the axial and coronal imaging planes. Conclusion MRI may demonstrate the origin, course, and branching of nerves in the heel and can provide a means for assessment of the patient presenting with chronic heel pain and suspected entrapment neuropathy.

Incidental findings in the cervical spine at CT for trauma evaluation.

OBJECTIVE CT is the standard of care for assessment of traumatic injuries. Because of the detail depicted with this technique, findings incidental to the injury are easily detected. We sought to determine the frequency and types of incidental findings in the cervical spines of trauma patients undergoing CT. MATERIALS AND METHODS The trauma registry was accessed to identify the cases of patients evaluated with cervical spine CT at a level 1 trauma center from January to July 2007. Trauma registry data, including age, sex, injury severity score, mechanism of injury, length of stay, and diagnosis were recorded, and all CT scans of the cervical spine were reviewed for incidental findings. Clinically significant incidental findings were classified according to bodily location, and the association between various patient characteristics and the likelihood of an incidental finding was assessed. RESULTS We identified incidental CT findings in 230 of 1,256 patients (18.3%) who underwent CT of the cervical spine during an initial trauma evaluation. We stratified the incidental findings as trauma-related and not trauma-related. The likelihood of non-trauma-related incidental findings was associated with age (p < 0.0001). The likelihood of trauma-related incidental findings was associated with injury severity score (p < 0.0001). CONCLUSION Incidental findings in the cervical spine were associated with age, injury severity score, and mechanism of injury. Awareness of the prevalence of incidental findings is important to assuring that both traumatic and nontraumatic pathologic findings are detected and appropriately managed.

Pathologic conditions of the ligaments and tendons of the knee

Excellent spatial resolution and unparalleled contrast resolution have allowed MRI to emerge as the dominant imaging modality for diagnosis of ligament and tendon pathology of the knee joint This article presents several important mechanisms of injury associated with tendon and ligament disruptions. When present, the pattern of bone contusions may reveal the vector of force. When one is aware of the mechanism of injury, it is possible to analyze systematically the structures of the knee and maximize the detection of pathology. Recognition of a knee dislocation pattern is important because the diagnosis may be unsuspected, and the clinician may have to be alerted to the possibility of vascular and neural injury.

MR patterns of involvement of humeral head osteonecrosis.

Purpose To characterize osteonecrosis of the humeral head on coronal and axial MR images. Methods We retrospectively reviewed MR examinations in patients with humeral head osteonecrosis. The angle of the entire affected articular surface at three levels was measured and an angle subtended by the margins of osteonecrosis was also measured. Results The appearance of osteonecrosis is identical to that in the femoral head with signal abnormality (13/13), double-line sign (7/13), and subchondral fractures (3/13). The superior aspect of the humeral head was the most common location of osteonecrosis. The MR staging resulted as follows: stage II (6/13), stage IIIA (1/13), stage IIIB (1/13), and stage IV (5/13). The maximum percentage of involvement of the articular surface demonstrated the following distribution: 0% to 25%, 0/11; 25% to 50%, 1/13; 50% to 75%, 5/13; and 75% to 100%, 7/13. Conclusions Quantitative analysis of the percentage of involvement of the humeral head was performed and indicates that in most cases, 75% to 100% of the articular surface at the levels measured was involved.

Osteonecrosis of the patella: Imaging features

Osteonecrosis of the patella, although uncommon, has become important to recognize because it can be a cause of pain in the knee. We describe the imaging manifestations of nontraumatic osteonecrosis of the patella in seven clinical cases. The lesions uniformly involved the superior aspect of the patella. Conventional radiography displayed increased radiodensity, subchondral radiolucent areas, and typical demarcation line surrounding the ischemic region. MR imaging and bone scintigraphy demonstrated the characteristic features of osteonecrosis. Recognition of the imaging findings of osteonecrosis involving the patella can preclude misdiagnosis and may obviate unproductive invasive diagnostic procedures.

A Problem of Mistaken Identity: Mimics of Musculoskeletal Neoplasms

Many processes may appear similar to osseous and soft tissue neoplasms on imaging studies. Traumatic, infectious, articular, metabolic, vascular, and dysplastic disorders, developmental lesions, and anatomic variants may demonstrate characteristics that can cause them to be misconstrued as tumors. E

Sonographic Evaluation of Extensor Tenosynovitis

This is a case report of tenosynovitis of the second and third extensor tendon compartments of the wrist. The report is unique in that tenosynovitis was evaluated with a combination of gray-scale sonographic images with and without an acoustic standoff pad, real-time examination, and color and spectral Doppler interrogation. Tenosynovitis is a nonspecific, inflammatory process affecting the tendon sheath and may occur as a result of infection, trauma, or inflammatory arthropathy such as rheumatoid arthritis. This case most likely represents an inflammatory type of extensor tenosynovitis. Symptoms, sonographic findings, and treatment options are briefly discussed.