contact lens use Indications & Contraindications

Indications of contact lens use

1. Optical indications include anisometropia, unilateral aphakia, high myopia, keratoconus and irregular astigmatism. Optically they can be used by
every patient having refractive error for cosmetic purposes.

Advantages of contact lenses over spectacles:
(i) Irregular corneal astigmatism which is not possible to correct with glasses can be corrected with contact lenses.

(ii) Contact lenses provide normal field of vision.

(iii) Aberrations associated with spectacles (such as peripheral aberrations and prismatic distortions) are eliminated.

(iv) Binocular vision can be retained in high anisometropia (e.g., unilateral aphakia) owing to less magnification of the retinal image.
 

 (v) Rain and fog do not condense upon contact lenses as
  they do on spectacles.
 

(vi) Cosmetically more acceptable especially by females and all patients with thick glasses in high refractive errors.

2. Therapeutic indications are as follows :
i. Corneal diseases e.g., non-healing corneal ulcers, bullous keratopathy, filamentary keratitis and recurrent corneal erosion syndrome.

ii. Diseases of iris such as aniridia, coloboma and albinism to avoid glare.

iii. In glaucoma as vehicle for drug delivery.

iv. In amblyopia, opaque contact lenses are used for occlusion.

v. Bandage soft contact lenses are used following keratoplasty and in microcorneal perforation.

3. Preventive indications include (i) prevention of symblepharon and restoration of fornices in chemical burns; (ii) exposure keratitis; and (iii) trichiasis.

4. Diagnostic indications include use during (i) gonioscopy; (ii) electroretinography; (iii) examination of fundus in the presence of irregular corneal astigmatism; (iv) fundus photography; (v) Goldmann's 3 mirror examination.

5. Operative indications. Contact lenses are used during (i) goniotomy operation for congenital glaucoma; (ii) vitrectomy; and (iii) endocular
photocoagulation.

6. Cosmetic indications include (i) unsightly corneal scars (colour contact lenses); (ii) ptosis (haptic contact lens); and (iii) cosmetic scleral lenses in
phthisis bulbi.

7. Occupational indications include use by (i) sportsmen; (ii) pilots; and (iii) actors.

Contraindications for contact lens use
(i) Mental incompetence, and poor motivation; (ii) chronic dacryocystitis; (iii) chronic blepharitis and recurrent styes; (iv) chronic conjunctivitis; (v) dryeye
syndromes; (vi) corneal dystrophies and degenerations; and (vii) recurrent diseases like episcleritis, scleritis and iridocyclitis.