<prompt> A 35 year old Lady Malti has unilateral headache, nausea, vomiting and visual blurring. The diagnosis isCluster headacheGlaucomaSubarachnoid haemorrhagePosterior fossa cyst.  <response>: Answer is B Glaucoma: Presence of visual blurring and female sex suggest a diagnosis of glaucoma over cluster headache amongst the options provided. Differential diagnosis are : Female patient Glaucoma is about four times more common in females while 80 of patients with cluster headache are males Visual blurring Visual blurring is a feature of Glaucoma. Cluster headache has ocular features mainly limited to reddening of eye and homolateral lacrimation but vision has not been mentioned as being affected. 