Alkyl groups may include amyl, isopropyl, isobutyl
Risk factors:
(1) heavy and frequent use
(2) isopropyl nitrite
Clinical features:
(1) bilateral decrease in visual acuity, rarely with blindness
(2) central photopsia (flashes of light)
(3) central scotoma
(4) improvement on discontinuation (abstinence)
Findings on the examination:
(1) yellowish spots in the fovea (in the center of the macula)
(2) disruption of the inner segment/outer segment (IS/OS) segment photoreceptor junction on spectral domain optical coherence tomography (SD-OCT)
Differential diagnosis:
(1) photic maculopathy (due to looking at bright lights)
(2) HIV-related ophthalmic infections
