The second specimen (Pl. IV., Fig. [22]) shows many features in common with the last. The lens is entire in its capsule, and is almost certainly Morgagnian; the tear in the retina through which it was thrust has now cicatrised up, leaving a puckered scar. The retina is totally detached, and on section the cataract lay as far forward as the separation of that membrane would permit. The pupil was blocked by exudate, and atrophic scars in the iris showed that there had been extensive laceration of that membrane. The globe was removed a year after operation.
The sequence of events in these two cases was possibly as follows: The posterior operation may have been adopted and the incision placed far back; a wide tear in the retina resulted; the lens, completely separated from its attachments, was kept entire by the toughness of the Morgagnian capsule, whilst the fluidity of its contents made its insinuation through the retinal tear an easy matter. The fact that a case has recently been recorded in which, in a boy of seventeen, the lens spontaneously escaped through a 2 mm. trephine hole throws a sidelight on such cases as these.
Accidental Injuries to Other Structures than the Lens during Couching.
Though the primary object of the Indian cataract coucher is to depress the lens, he may accidentally injure any or all of the other structures of the eye. Evidence of such damage is obtained both clinically and pathologically.
The Cornea.—Opaque scars on the cornea are quite frequently seen in the out-patient room in eyes which have been subjected to the anterior operation, but are rendered invisible in formalin-mounted specimens owing to the opacification of the membrane. Other evidence of corneal injury is, however, available.
In No. 9 a corneal fistula is present, lying to the inner side of the centre of the eye (Pl. IV., Fig. [23]). The lamellæ immediately surrounding it are largely replaced by connective tissue; the whole thickness of the membrane is markedly reduced, and the lining epithelium is irregular and vacuolated. The iris is very closely adherent to the back of the cornea near the fistula, but more loosely attached farther out. There has evidently been some ulceration of the cornea and the formation of a limited staphyloma, which burst at a later date, leaving the fistula now seen. It is probable that the point of fistulisation was determined by the use of a septic instrument at the time of operation, and that septic keratitis followed, leading to early perforation with entanglement of the iris. On the other hand, it is possible that the enclavement of the iris occurred as the instrument was withdrawn. In either case, the later sequence of events included a secondary rise in tension, the formation of a staphyloma, and a fresh perforation at the weakest point, resulting in the production of a permanent fistula.
In No. 45 the lens capsule is adherent to the back of the cornea, the iris being widely torn, and being probably also involved in the synechia (Pl. IV., Fig. [24]). All that remains of the lens is a brown nucleus; the cataract was evidently Morgagnian. It is probable that, after the escape of the fluid it contained, the lax capsule prolapsed into the wound, either with the gush of fluid which accompanied the withdrawal of the instrument or at a later date.
Fig. 22: Specimen No. 138.—A large Morgagnian cataract in its capsule lies dislocated behind the totally detached retina; the tear in the front part of the lower half of the retina, through which the lens was thrust, is now represented by a wide puckered scar.
Fig. 23: Specimen No. 9.—A whole-section showing a persistent fistula of the cornea.