Primary investigation of choice in a patient with suspected subarachnoid haemorrhage should be:: (A) Non-contrast computed tomography, (B) Magnetic resonance imaging (MRI), (C) Contrast-enhanced computed tomography, (D) Lumbar punture
Answer is A. Here the investigation of choice is Non-contrast CT; if it is not successful lumbar puncture can be tried. The most sensitive investigation is Digital subtractions angiography of both carotid and veebral aeries. Ref: Mauricio Castillo (2006), Chapter 8, "Trauma", In the Book, "Neuroradiology Companion: Methods, Guidelines, and Imaging Fundamentals" 3rd Edition, Lippincotts Publications, USA, Page 52 ; Current Medical Diagnosis and Treatment, 2003, Page 965