- Turbidity/avilata, oedematous look of eye/sasarambhata, frequent watering of eye, itching, profuse secretions/upadeha, heaviness/guruta indicates Kapha vitiation.
- Burning sensation indicates Pitta vitiation.
- Redness indicates Rakta vitiation.
- Pricking sensation/toda, Foreign body sensation/bristle like movements with some pain in fornix indicates Vata vitiation. (S. U. 1-21 to 23)
Being Prodromal features, these are not clearly expressed or visualized. But in such conditions also if there is visual impairment or impaired lid movements, then the wise clinician should understand that the Eye is occupied by various Vitiated Dosha.
Indriya-Aayatan Dosha / Disorders of sense organs
When the sense organs are unable to perceive/interpret or interpret the received sensations in a twisted manner, the condition is called as Indriya-Aayatan Dosha i.e. Disorders of sense organs. (S. Su.24-9)
[Karana daurbalya i.e. weakness of sense organ, mentioned in Charaka Su. 11-8, is also responsible for improper functioning of sense organ.]
Vitiation of Dosha is the main etiological factor for Eye diseases along with some anatomical / structural defects; physiological i.e. functional anomalies; adibala pravrutta, janmabala pravrutta etc. (S. Su. 24-5); Asatmendriyartha sanyoga, Pradnyaparadha and Parinama (C. Su. 11-43). Besides these some specific etiological factors for eye diseases are also mentioned in S. U. 1-26, 27; A.H.U.8-1, 2 and Madhava Nidana Uttarardha-page 690. All these etiological factors are listed in a tabulation form as under-
Chart showing different Hetu of Netraroga:-
Adibala pravrutta (Hereditary)-Naktandhata (Night Blindness), Rhaswadrushti (Myopia), shuklandhata (Albinism); Janmabala pravrutta (Congenital)-coloboma of iris-retina, congenital cataract etc.; Dosha-bala pravrutta (humoral); Sanghata-bala pravrutta: injuries by physical, mechanical and chemical factors- eclip’s burn, perforating injury to eye, traumatic cataract, amblyopia etc. ; Kala-bala pravrutta/Rutujanya-spring catarrh, vernal conjunctivitis; Daiva-bala pravrutta: Accidental injuries; Swabhava-bala pravrutta (degenerative)-arcus senilis, senile cataract, senile macular degeneration.
Charaka– also mentioned Karana daurbalyata i.e. weakness of sense organ and Mano-anavasthanat i.e. inattentive / unstable mind (C. Su. 11-8).
All these hetu can also be classified in to (a) Exogenous and (b) Endogenous etiological factors as under-
Ushnabhitaptasya Jalapraveshat, abhighata/traumati injury, Exposure to dust, fumes, smoke; high temperatures like furnaces, welding etc; contact with allergens like pollens, some vegetables, animal dust/hairs, various drugs like atropine, penicillin etc; inhaling poisonous gas, touching or smelling poisonous flowers, consuming ethyl/methyl alcohol, arsenic, quinine, salicylate or tobacco etc (causing Sanimitta and Animitta Linganasha i.e. Amblyopia/eclipse burn).
Endogeneous Hetu– All the other hetu except those mentioned in exogenous.