The history of cataract surgery: from couching to phacoemulsification

Where and when cataract surgery started have been a mystery. Indian tradition and the Persian author Zarrin-Dast attributed the procedure to the Indians, while pseudo-Galen suggested an Egyptian origin. Certain idiosyncratic practices are common to early Greek and Sanskrit descriptions of cataract couching, e.g., the requirement for maturity of the cataract, the preference for patients of intermediate ages, comparison of some eyes to glass, rubbing the eye, having a wide portion of the couching instrument shaft, pars-plana puncture with avoidance of the vein, and immediate vision testing. In ancient Greece and India, the words describing the color of a healthy blue eye (glaukos and nīla, respectively) could also characterize a poorly-seeing eye not curable by surgery. In both regions, the lens (or pupillary region) was compared to a lentil, and colored entoptic phenomena were noted. The sitting posture of the patient, ocular convergence towards the nose, the more systematized integration of the humoral theory with cataract surgery, and possibly blowing on the eye and putting cotton on the eye are all consistent with an Indian origin for the procedure. On the other hand, the emphasis on surgical ambidexterity could suggest an origin close to the Mediterranean. Thus, the question of where cataract surgery started has not been resolved. Various authors have suggested that multiple types of cataract surgery were practiced in the ancient and medieval periods: (I) couching, (II) discission (division), (III) aspiration through a tube, (IV) extraction through a limbal incision, and (V) expulsion of lens remnants around an embedded probe. We review the evidence in favor (and against) each of these types of surgery.