Low field MR imaging of sellar and parasellar lesions: experience in a developing country hospital.

BACKGROUND: Magnetic resonance imaging (MRI), an advancement which followed computed tomography (CT) is expensive and inaccessible in most developing countries. However it is the procedure of choice in evaluating sellar and parasellar lesions. Its major advantages are its superior soft tissue contrast differentiation, its capacity for multiplanar imaging and nonexistence of ionising radiation. Its use is relatively new in Nigeria, a developing economy in Africa. Since its introduction in 2005, it has been utilised extensively for neuroimaging at the University College Hospital (UCH), Ibadan; a large hospital in south-western Nigeria. OBJECTIVE: To review the role and pattern of low field MR Imaging in sellar and parasellar lesions presenting to a tertiary care centre in Nigeria. METHODS: All 62 patients with clinically suspected sellar and parasellar masses, referred to the Department of Radiology, UCH Ibadan for MRI between December 2006 and January 2010 were retrospectively analysed. The examinations were performed using an open 0.2T permanent magnet MR unit. T1W, T2W, T2/FLAIR, TOF and T1W post gadolinium DTPA sequences of the sellar region were obtained. RESULTS: Of the 62 patients, there were 27 males and 35 females. The modal age group was 40-49 years with a mean age of 39.94 years (±16.65 years). Twenty-four cases (38.7%) had histological diagnosis, of which 20 (83.3%) were consistent with initial MRI diagnosis. Pituitary adenomas were the commonest (58.06%) lesions of the sellar and parasellar regions. Others include parasellar meningiomas, cranipharyngiomas, and giant aneurysms. Headache and visual impairment were the major presenting features and showed no significant correlation with tumour size. CONCLUSION: The use of low field MRI in the diagnostic evaluation of patients with suspected sellar or parasellar lesions in developing countries of low economic resource is commendable as it provides beneficial outcomes in management.

Experience with three-dimensional computed tomographic angiography in Ibadan, Nigeria.

INTRODUCTION: The latest versions of spiral CT scanners have provided the radiologist with unparalleled capabilities for vascular imaging. Computed Tomographic Angiography (CTA) has the potential of revolutionizing vascular imaging and with evolving improvements may replace conventional angiography in the near future OBJECTIVE: To report our initial experience with CTA in Nigeria; highlighting its usefulness as a non invasive modality and its clinical applications in diagnosis of vascular abnormalities of various parts of the body. MATERIALS AND METHODS: We reviewed 62 patients who had CTA between December 2003 and September 2005.. The studies were performed using a spiral technique with GE CT/e single-slice scanner (General Electric Medical Systems) having a gantry rotation period of one second. Details of techniques of data acquisition, methods of 3-D reconstruction and clinical applications are discussed. RESULTS: Vascular abnormalities were demonstrated in 26 (42%) patients including 5 cranial arteriovenous malformations (AVMs), 3 intracranial aneurysms, 1 spinal AVM, 3 aortic aneurysms, 5 carotid artery stenosis, and 2 traumatic peripheral aneurysms. CONCLUSION: Correlations between CTA and surgical findings were good. CT angiography has enhanced our practice of vascular radiology in Ibadan as it has done in the west and other parts of the world.