Periosteal desmoid.

Periosteal desmoid is a benign tumor like reactive fibrous lesion developed by repeated micro trauma. We describe the case of a 14 year old boy with pain in his right knee who underwent plain radiography followed by radionuclide bone scan. The final diagnosis was that of periosteal desmoid.

Primary lymphoma of the cervix.

A 62-years old female presented with postmenopausal vaginal bleeding for one month. On vaginal examination soft fungated mass was palpated in cervix that bled to touch. Ultrasound, CT scan and MRI showed well-defined mass in cervix. On biopsy it was proved to be a primary non-Hodgkin's lymphoma.

Ultrasound differentiation of benign versus malignant solid breast masses.

OBJECTIVE: To determine the reliability of ultrasonographic features in differentiating benign from malignant solid breast masses. DESIGN: Descriptive, analytical study. PLACE AND DURATION OF STUDY: Radiology Department, Aga Khan University Hospital, Karachi from July 2000 to June 2002. SUBJECTS AND METHODS: One hundred solid breast masses in females with a tissue diagnosis available were reviewed. Two radiologists reviewed the sonographic features of masses without knowledge of clinical history or histologic examination results. Ultrasound features were corrected later with histologic features to determine the reliability of the former in benign or malignant nature of nodules. RESULTS: Ultrasound features that most reliably characterize masses as benign were a round or oval shape, circumscribed margins and a width to antero-posterior (AP) dimension ratio greater than 1.4. Features that characterized masses as malignant included irregular shape, spiculated margins and width to antero-posterior (AP) dimension ratio of 1.4 or less. If these three most reliable criteria had been strictly applied by the primary reporting radiologist, the overall cancer biopsy yield would have increased. CONCLUSION: The data confirms that certain ultrasound features can help differentiate benign from malignant masses. However, practice and interpreter variability should be further explored before these criteria are applied to defer biopsy of solid masses.

Accuracy of magnetic resonance imaging in the knee.

OBJECTIVE: To determine the accuracy of magnetic resonance imaging (MRI) in the assessment of various knee disorders in comparison with arthroscopic findings and pathologic diagnosis. DESIGN: A retrospective and comparative study. PLACE AND DURATION OF STUDY: Radiology Department, Aga Khan University Hospital, Karachi, from 01-12-1996 to 30-06-2000. PATIENTS AND METHODS: Fifty-six subjects (36 males and 20 females), included in this study, had abnormal findings on MRI, which were correlated with arthroscopic findings in 50 cases and pathological diagnosis in 6 cases. Plain X-rays were available in all cases. RESULTS: The sensitivity, specificity and accuracy for MRI of the menisci and cruciate ligaments were as follows: medial meniscus pathologies 87% sensitivity, 94% specificity and 92% accuracy; lateral meniscus pathologies 92% sensitivity, 89% specificity and 90% accuracy; anterior cruciate ligament injuries 95% sensitivity, 96% specificity and 96% accuracy and posterior cruciate ligament injuries 100% sensitivity, 98% specificity and 98% accuracy. Pathological diagnosis was available in 6 cases. MR imaging suggested the diagnosis of tuberculosis and metastases as well as mapped out the extent of osteogenic sarcoma, fibromatoses and rhabdomyosarcoma. CONCLUSION: This study confirms that MR imaging of the knee is highly sensitive, specific, and accurate.

Unenhanced helical CT scan for the investigation of acute ureteral colic.

Unenhanced helical CT is presently considered a superior imaging technique for investigating acute urinary colic compared to intravenous urography and ultrasound. It was introduced in Pakistan around the year 2000 and is in the process of being acknowledged as the first line investigation in emergency departments. We have discussed the advantages and the disadvantages of the technique, and have compared it with other imaging modalities.