Robert J. Coombs

Computed tomography findings in patients with sacroiliac pain.

This retrospective study evaluated the diagnostic value of computed tomography in patients with sacroiliac pain. Computed tomography scans of the sacroiliac joints of 62 patients with sacroiliac joint pain were reviewed. The criteria to include the patient in the current study were pain relief after a local injection in the sacroiliac joint under computed tomography guidance, a physical examination consistent with a sacroiliac origin of the pain, and negative magnetic resonance imaging of the lumbar spine. A control group consisted of 50 patients of matched age who had computed tomography scans of the pelvis for a reason other than pelvic or back pain. Computed tomography scans showed one or more findings in 57.5% and 31% of the sacroiliac joints in the symptomatic and the control groups, respectively. The computed tomography scans were negative in 37 (42.5%) symptomatic sacroiliac joints with a positive sacroiliac joint injection test. The sensitivity of computed tomography was 57.5% and its specificity was 69%. The finding of the current study suggests limited diagnostic value of computed tomography in sacroiliac joint disease because of its low sensitivity and specificity. With clinical suspicion of a sacroiliac origin of pain, intraarticular injection is currently the only means to confirm that diagnosis.

Reduction of postoperative CT artifacts of pelvic fractures by use of titanium implants

The value of CT scanning for both preoperative and postoperative assessment of pelvic and acetabular fractures has been demonstrated. Previous attempts at our institution to obtain useful pelvic CT scans following internal fixation with stainless steel implants have been impaired by metal artifacts that degraded the transaxial CT images. Our use of titanium, instead of stainless steel implants, produced identical fixation and ultimate fracture healing, but yielded minimal artifacts. We recommend the use of titanium implants as substitutes for stainless steel implants in pelvic fixation to maximize the information obtained on subsequent CT exams.

Magnetic resonance imaging for ineffectual tarsal tunnel surgical treatment.

Tarsal tunnel syndrome (TTS) is an entrapment neuropathy caused by compression of the posterior tibial nerve beneath the ankle flexor retinaculum. Treatment of TTS consists of surgical release of the retinaculum. The failure rate is 10%-20%. Magnetic resonance (MR) imaging was used to evaluate a patient with an unsatisfactory response. MR imaging demonstrated incompleteness of the surgical release of the flexor retinaculum.

Chronic bursitis presenting as a mass in the pes anserine bursa : MR diagnosis

A case of chronic, nonspecific synovial inflammation presenting as a mass in the pes anserine bursa is demonstrated by MRI. The lesion was well demarcated and surrounded by a low intensity rim. On spin echo images it was homogeneous and of intermediate signal intensity, whereas on T2-weighted images it showed scattered areas of high signal producing a heterogeneous pattern. It is contrasted with a typical example of acute pes anserine bursitis, presenting as simple fluid within the bursa. The differential considerations vary accordingly between the acute and chronic forms of pes anserine bursitis, with the latter requiring differentiation from other forms of synovitis, synovial hemangioma, and synovial sarcoma. The MR features of these entities are reviewed as an aid in differential diagnosis.

Normal Magnetic Resonance Anatomy of the Tarsal Tunnel

Images of five cadaver ankles and three normal volunteers were obtained in an attempt to delineate magnetic resonance (MR) anatomy of the tarsal tunnel. Multiplanar T1-weighted (TE 20 msec, TR 600 msec) scans were obtained of the cadaver specimens while T1 and T2 weighted (TE 20, 80 msec, TR 2000 msec) scans were obtained of the volunteer ankles. After imaging, the cadaver ankles were frozen, sectioned, photographed, and compared to the MR images in the transverse plane. The anatomical structures seen on the MR images correlated closely with the cadaver sections. The bony and soft tissue boundaries and contents of the tarsal tunnel could be imaged with detail easily sufficient to delineate all the major structures within it, including the posterior tibial nerve and its branches

Myelolipoma of the liver: CT features.

A case of myelolipoma of the liver is reported. Computed tomography, ultrasound, and angiography of the lesion is described and compared with previous reports.

Magnetic resonance imaging of the calcaneus: normal anatomy and application in calcaneal fractures.

Images obtained from normal volunteers demonstrate highly detailed anatomy of the soft tissue and bony structures near the calcaneus and subtalar joint. Cortical bone, marrow, articular cartilage, ligaments, tendons, muscles, fibrous tissue, vascular bundles, and nerves can be identified. However, images obtained of acute calcaneal fractures were found to offer unsatisfactory depiction of bony anatomy. The presence of small fragments was obscured by a change in normal marrow signal by contusion, hemorrhage, and edema, and by the inability of magnetic resonance (MR) to image small pieces of cortical bone. Only in rare instances might MR be helpful in the acute setting when the location or displacement of tendons cannot be clearly ascertained with computed tomography (CT). MR may prove more useful in the long-term follow-up of healed fractures with persistent pain. In this setting it might be used in the diagnosis of complications such as residual or recurrent tendon displacementdon displacement, tenosynovitis, heel fat integrity, and tarsal tunnel evaluation. However, this paper did not directly compare the efficacy of MR with that of CT in the long term. Therefore, the degree to which MR may eventually supplement or supplant CT is unclear and further study is required before the use of MR can be recommended in the routine clinical follow-up of calcaneal fractures.

CT-GUIDED BIOPSY OF METASTATIC SACRAL TUMORS

Between June 8, 1985 and January 29, 1986, the authors performed five CT-guided needle biopsies of suspicious sacral lesions. In each of the five cases, these biopsies allowed the acquisition of specimens suitable for definitive pathologic diagnosis. Three cases of metastatic adenocarcinoma, one case of desmoplastic fibroma, and one case of chronic inflammatory changes were noted. In the case involving chronic inflammatory changes, subsequent open biopsy was performed, confirming the inflammatory changes and absence of neoplasm. The authors conclude that percutaneous CT-guided biopsy of sacral lesion can be performed safely and rapidly, and allows accurate diagnosis and treatment of sacral lesions.

The c-myc x E2F-1/p21 interactive gene expression index augments cytomorphologic diagnosis of lung cancer in fine-needle aspirate specimens

Morphological analysis of cytologic samples obtained by fine-needle aspirate (FNA) or bronchoscopy is an important method for diagnosing bronchogenic carcinoma. However, this approach has only about 65 to 80% diagnostic sensitivity. Based on previous studies, the c-myc x E2F-1/p21WAF1/CIP1 (p21 hereafter) gene expression index is highly sensitive and specific for distinguishing normal from malignant bronchial epithelial tissues. In an effort to improve sensitivity of diagnosing lung cancer in cytologic specimens, we used Standardized Reverse Transcriptase Polymerase Chain Reaction (StaRT-PCR) to measure the c-myc x E2F-1/p21 index in cDNA samples from 14 normal lung samples (6 normal lung parenchyma and 8 normal bronchial epithelial cell [NBEC] biopsies), and 16 FNA biopsies from 14 suspected tumors. Based on cytomorphologic criteria, 11 of the 14 suspected tumors were diagnosed as bronchogenic carcinoma and three specimens were non-diagnostic. Subsequent biopsy samples confirmed that the three non-diagnostic samples were derived from lung carcinomas. The index value for each bronchogenic carcinoma was above a cut-off value of 7000 and the index value of all but one normal sample was below 7000. Thus the c-myc x E2F-1/p21 index may augment cytomorphologic diagnosis of bronchogenic carcinoma biopsy samples, particularly those considered non-diagnostic by cytomorphologic criteria.

Case report 360

This patient is a 16-year-old girl who presented with a complaint of progressively increasing pain in her left shoulder. Approximately 11 months prior to her admission to hospital, she had experienced a sharp pain in the posterior aspect of her left shoulder, following a fall on her outstretched left arm. The pain disappeared after two weeks only to recur three months later. The patient was treated with physical therapy, but gained no relief. Three months before her admission to hospital, a diagnosis of a neuropathy of the left long thorac-