Kristi Sharma, B.Optom

M.Optom Student, The Sankara Nethralaya Academy, Chennai, India



People, especially parents, often complain about how the use of smartphones has been contributing to vision loss. It is true in many aspects. For one, use of smart phones has increased the progression of myopia in paediatric age groups. But recently, it has been found that smartphones are not only affecting the refractive power of the eye but also causing some phenomena which is termed as Transient Smartphone Blindness or TSB.(1)

What is Transient Smartphone Blindness?

Transient Smartphone Blindness is a phenomenon in which there is acute, painless, transient loss of vision following smart phone use while lying in the dark, which is usually unilateral, but can be rarely bilateral as well.(2) It can be a physiological adaptation to the different retinal sensitivities of the two eyes; hence a thorough history needs to be taken for differentiation from other ocular conditions.

Image courtesy: Getty Images


The phenomenon was reported first in 2016, where the patients complained of loss of vision in one eye after using a smartphone in the dark while lying down. This was mostly associated with the eye on the side while lying was covered and the other eye was mainly seeing the phone. That eye was reported to have a loss of vision which self-resolved after a few minutes. Findings of all other systemic and ocular examinations were normal.(2)

It can be hypothesised to be due to temporary discrepancy in bleaching of photopigment and ultimate light adaptation between the two retinas. The current hypothesis says that in low light, if the individual lies in a position where one eye is functionally blocked (such as with a pillow), the blocked eye becomes dark-adapted while the other eye exposed to the bright screen of the device becomes light-adapted.(2,3)


  • Transient, painless, acute loss of vision, which self resolves.
  • Mostly monocular, rarely binocular.


It is expected that visual acuity, pupillary evaluation, intraocular pressure, confrontation test, extraocular motility and colour vision will be normal in these patients. Humphrey Visual Field (HVF), Optical Coherence Tomography (OCT) and Magnetic Resonance Imaging (MRI) will also not have any abnormalities.

Differential Diagnosis

  • Thromboembolic diseases: Vision loss occurs in these diseases following occlusion of the retinal blood vessels resulting in interrupted blood flow. It cannot resolve if left untreated.
  • Non-arteritic anterior ischaemic optic neuropathy (NAION): Visual loss will be associated with other signs such as colour vision defect, swollen optic nerve and Relative Afferent Pupillary Defect (RAPD).
  • Multiple sclerosis: In multiple sclerosis, the optic nerve is inflamed, which is known as Optic Neuritis. Vision loss in multiple sclerosis is accompanied by eye pain with movement in that eye.


The patients are be advised not to use smart phones in the dark, especially not with one eye occluded.(4)


Smartphone, blindness, transient



  1. Nishay Bhatnagar, Jacob Winters, Neelakshi Bhagat. (2023). Transient Smartphone Blindness. American Academy of Ophthalmology
  2. Alim-Marvasti, A., Bi, W., Mahroo, O. A., Barbur, J. L., & Plant, G. T. (2016). Transient Smartphone “Blindness”. The New England journal of medicine374(25), 2502–2504.
  3. Wingerchuk, D. M., & Sathiamoorthi, S. (2017). Author response: Transient smartphone blindness: Relevance to misdiagnosis in neurologic practice. Neurology89(3), 306–307.
  4. Hasan, C. A., Hasan, F., & Mahmood Shah, S. M. (2017). Transient Smartphone Blindness: Precaution Needed. Cureus9(10), e1796.