Fig. 19.—V-shaped iridotomy with scissors (Maunoir).
Fig. 20.—Parallelogram pupil (Maunoir).
Maunoir,[24] in 1802, took up the method of Janin, with the object of improving it. He made an incision near the corneal margin, through which he introduced a pair of long, thin, angular scissors of his own design (Fig. [18]), one blade of which was sharp-pointed like a lancet, and the other button-pointed like a probe. The iris-membrane was then punctured by the sharp blade at about the natural location of the pupil, and an incision executed toward the ciliary margin of the iris. Finding that this single incision did not always succeed,[25] he subsequently improved this method by making a second incision from the pupillary area toward the iris margin, in the line of the radiating iris fibers, thus making a divergent V (Fig. [19]). This triangular flap was then allowed to shrink back, or if too stiff, was drawn out and excised. The resultant pupil assumed the shape either of a triangle, a parallelogram (Fig. [20]), or a crescent (Fig. [21]). He always made his incision parallel with the radiating fibers of the iris and across the circular fibers.
Fig. 21.—Crescent pupil (Maunoir).
Scarpa,[16] in 1818, having abandoned his own method of iridodialysis as wholly unsatisfactory, adopted Maunoir’s procedure with enthusiasm, chiefly because he had by a friendly correspondence[25] personally encouraged Maunoir with advice and suggestion during its development. He indorsed Maunoir’s plan of a double incision when he stated his conviction that “experience has proved that in order to obtain, with the most absolute certainty, a permanent artificial pupil, it is necessary to make two incisions in the iris so as to form a triangular flap in the membrane, in the form of a letter V, the apex being precisely in the center of the iris and the base near the great margin.” Some have claimed that Scarpa himself originated the V-shaped incision, but he gives Maunoir full credit for its successful accomplishment, although he does suggest some additional indications for its practical application.
His opposition to the knife-needle incision of Cheselden arose from the fact that the pupil either did not open, or if it did open would not remain permanent, chiefly because of the single iris incision. His antagonism to the more successful procedure of Adams was the result of a caustic personal controversy[17] with that skilful surgeon, who ably parried his charges.[15] His great influence with the profession of that day, however, served to check the sentiment in favor of Adams’ procedure, and when the weight of his indorsement was cast in favor of Maunoir’s operation the scales were decisively turned toward the side of the scissors method.
Mackenzie,[26] in 1840, practiced Maunoir’s operation with considerable success, but in certain cases found it necessary to employ a slight modification of this procedure. He reversed Maunoir’s incision by making the same divergent V across the radiating fibers of the iris instead of parallel with them (Fig. [22]), thus securing a triangular pupil (Fig. [23]), which Lawrence[27] thought might succeed in some cases where Maunoir’s method would not be available.
