Thread by @hyderabaddoctor

A common habit resulted in severe #vision impairment in a young woman

1. 30-year old Manju had severe disabling vision symptoms for one and half years. This included seeing floaters, bright flashes of light, dark zig zag lines and at times inability to see or focus on objects.

2. There were moments when she could not see anything for several seconds. This occurred mostly at nights when she got up to use washroom. She was evaluated by an #eye specialist and detailed evaluation was found to be normal.
She was referred to rule out neurological causes.

3. I reviewed the history. Symptoms had started after she quit her job of a beautician in order to take care of her specially abled child.
She picked up a new habit of browsing through her smartphone for several hours daily, including >2 hours at nights with lights switched off.

4. The diagnosis was obvious now. She was suffering from smartphone vision syndrome (SVS). Long-term use of devices such as computer, smartphones or tablets can cause various eye-related disabling symptoms, referred to as computer vision syndrome (CVS) or digital vision syndrome.

5. I did not order any investigations nor did I prescribe any medicines (even though Manju requested, as she was anxious). I counseled her about the possible cause for her vision impairment and suggested her to minimize the use of smartphone.
#MedTwitter #NeuroTwitter

6. Manju was anxious as she feared something sinister with her brain nerves but was finally determined to take corrective action.
She said- "instead of minimizing, I will stop looking at smartphone screen, unless absolutely necessary. In any case, my phone use is recreational."

7. At 1-month review, Manju was absolutely fine. Her vision impairment of 18 months had gone. Now, she had normal eyesight, did not see any floaters or flashes of light. Moreover, her momentary loss of vision at nights also stopped.
Our suspicion was proved right.

8. Take home message:
*Avoid looking at screens of digital devices for long, as it can cause severe and disabling vision-related problems.
*Take 20-second break, every 20 min, to look at something 20 feet away, while using a digital screen (20-20-20 rule).

9a. 66% of a sample had computer vision syndrome (CVS).
Being female, improper body posturing, use of electronics devices out of work, no habit of taking a break, long-hour duration of visual display terminal use & short-distance screen were associated with increased odds of CVS

9b. Reference
doi.org/10.1177/205031…

10. Many cases of transient smartphone-induced blindness have been reported in people using smartphones on bed in darkness.
doi.org/10.4045/tidssk…
doi.org/10.1016/j.jfo.…

11a. Spectral peaks for smartphones are very similar to short-wavelength blue visible light. Damage to retina caused by light, especially blue light is well-established.
A case of retina damage causing blurring of vision in both eyes due to smartphone use at nights was reported.

11b. Reference
doi.org/10.1097%2FCM9.…