Joseph M. Bestic

Postoperative Evaluation of the Total Ankle Arthroplasty

OBJECTIVE The purpose of this article is to review the basic design features of second-generation total ankle arthroplasty components and to illustrate the normal and abnormal postoperative imaging features associated with such devices. The usefulness of CT in postoperative evaluation will be highlighted. CONCLUSION Postoperative evaluation of the total ankle arthroplasty necessitates a familiarity with the various designs currently in use. Radiography serves as an integral component in the postoperative evaluation of such devices, with CT offering further characterization of radiographic abnormalities.

Benign synovial tumors and proliferative processes.

This article discusses several benign tumors and proliferative processes of the synovium including giant cell tumor of the tendon sheath, pigmented villonodular synovitis, synovial chondromatosis, lipoma arborescens, and synovial hemangioma, lipoma, and fibroma. We review the clinical features and imaging characteristics of each entity, with a special focus on the unique imaging findings that can enable a confident diagnosis or a limited differential diagnosis.

Postoperative Imaging of the Total Ankle Arthroplasty

Promising results reported with currently available total ankle arthroplasty designs have led to an increased use of such devices as an alternative to ankle arthrodesis. Despite recent improvements in implant design and surgical technique, complications associated total ankle arthroplasty devices continue to be reported. Postoperative evaluation of total ankle arthroplasties relies on a combination of clinical and radiologic assessment. Familiarity with commonly used current total ankle arthroplasty devices and appropriate postoperative imaging techniques is imperative for effective characterization of the expected postoperative imaging appearances of such devices and facilitating detection of potential postoperative complications.

Sclerosing Variant of Well-Differentiated Liposarcoma: Relative Prevalence and Spectrum of CT and MRI Features

OBJECTIVE The purpose of this study was to determine the relative prevalence of the sclerosing variant of well-differentiated liposarcoma at one institution and to elucidate the CT and MRI characteristics of this subtype of well-differentiated liposarcoma. MATERIALS AND METHODS A retrospective computerized search was conducted to calculate the relative prevalence of the sclerosing variant of well-differentiated liposarcoma among all well-differentiated liposarcoma subtypes at one institution. The MRI and CT features of a total of 19 cases of pathologically proven sclerosing variant of well-differentiated liposarcoma were evaluated (seven identified from the study institution database and 12 cases contributed by other institutions). RESULTS The cases of a total of 36 patients with well-differentiated liposarcoma were identified in the pathology database; six (17%) cases had evidence of dedifferentiation. Seven (19%) cases of sclerosing variant of well-differentiated liposarcoma were identified. Of these, three (43%) had evidence of dedifferentiation. On images, the sclerosing variant of well-differentiated liposarcoma typically presented as a large (average, 16.6 cm) well-circumscribed heterogeneous mass most commonly situated in the retroperitoneum (58%). Sixteen of the 19 tumors evaluated (84%) had predominantly well-circumscribed margins. Tumor composition ranged from predominantly fatty to entirely devoid of macroscopic fat; only three (16%) were composed of more than 75% fat. Variable amounts of nonlipomatous elements were identified in all cases. Enhancement of these elements was evident at CT or MRI in all 14 cases in which enhancement could be reliably assessed. CONCLUSION The sclerosing variant of well-differentiated liposarcoma should be included in the differential diagnosis of any well-circumscribed lipomatous mass containing variable amounts of nonlipomatous elements, particularly when located in the retroperitoneum. Unlike other subtypes of well-differentiated liposarcoma, the sclerosing variant is less likely to be composed predominantly of fat and may be associated with an increased propensity for dedifferentiation.

Magnetic resonance imaging to detect vesico-symphyseal fistula following robotic prostatectomy

Pubic complications following radical prostatectomy are rare. Osteitis pubis typically presents with symptoms related to irritation of the pubic rami including pain with ambulation and adduction of the leg. A 60-year-old male with prostatic adenocarcinoma underwent uneventful robotic assisted laparoscopic prostatectomy. The patient noted the onset of severe pubic pain exacerbated by ambulation approximately one month post-surgery. An abdominal/pelvic CT scan was negative for acute pathology. Due to continued discomfort, a multiplanar MRI of the pelvis was performed with and without intravenous contrast material (20 ml Omniscan). The MRI demonstrated irregularity of the bladder base and proximal urethra with a fistulous tract extending anteriorly in direct communication with the pubic symphysis joint space. Vague periarticular marrow edema-like signal and enhancement at the pubic symphysis was thought to represent osteitis pubis. The patient’s symptoms resolved after one month of urethral catheter drainage, intravenous antibiotics, and anti-inflammatory therapy.