Illuminated Frenzel glasses are used in detecting: (A) Nystagmus, (B) Heterophoria, (C) Esotropia, (D) Astigmatism
Answer is A. (Refer: AK Khurana Comprehensive Ophthalmology, 6th edition, pg no. 358 - 362)Illuminated Frenzel glasses (+20 lenses) are useful for abolishing fixation and thus revealing peripheral vestibular nystagmus