use of actual equivalents i.e. 'optical/visual distortion' can be be understood as medical terms indicating some serious health condition/illness, so visual disturbance may fit the context better.

Visual distortion can be caused by corneal thinning or distortion, and may include keratoconus, astigmatism, and myopia. Symptoms include deterioration in vision and reduced ability to do tasks like read or drive

Optical distortion is something that affects all lenses to some extent. ... This type of distortion is most common in wide angle or fisheye lenses.

Visual disturbances occur when you experience a change in your vision that is not indicative of normal eye health. ... Floaters are blobs or spots in your vision, and most people will experience these at some point in their lives.

بصري من كلمة البصر يعني
Vision

تشوه في هذا السياق يعني
distortion

meaning a change to the intended or true meaning of something

أي تغيير في المعنى المقصود أو الحقيقي لشيء ما أو تشويه