Comparison of T2 weighted fat suppressed turbo spin echo and contrast enhanced T1 weighted spin echo MRI in nasopharyngeal carcinoma.

Fat suppressed T2 weighted fast imaging sequences have recently been favoured in MRI of head and neck tumours. The purpose of this study was to evaluate the use of T2 weighted fat suppressed turbo spin echo (T2W SPIR) and compare it with our standard technique, the gadolinium-enhanced T1 weighted spin echo (Gd-T1W SE). The MR images of 36 patients with nasopharyngeal carcinoma were analysed for local tumour extent. T2W SPIR was better in evaluating tumour extension into the clivus and fascia. In all other regions Gd-T1W SE was either better (nasopharyngeal walls, small parapharyngeal muscles, parapharyngeal fat space, paranasal sinuses, pterygomaxillary fissure and pterygoid process) or equal (nasal cavity, oropharynx, cranial fossa and cavernous sinus) to T2W SPIR. T2W SPIR was unable to replace Gd-T1W SE in evaluation of tumour extent because of loss of signal from magnetic susceptibility artefact, poor delineation of anatomical detail and reduced tumour conspicuity. The use of T2W SPIR as an additional sequence may be warranted in selected cases but cannot replace Gd-T1W SE.