also in a pediatric patient. 6 This operation followed the observation that perforating keratoplasty for a severe perforating corneal wound (a common cause of traumatic cataract in pediatric patients) was sim­plified by the prior implantation of an intraocular lens.

In short, I am not claiming to be the first to have used an IOL in the treatment of recent unilateral traumatic aphakia in children; I think credit for this probably belongs to Strampelli. I am fairly certain, however, that I was the first to stress the advantage of so doing in a scientific communication.

D.P. Choyce, M.S., F.R.C.S. London, England

REFERENCES

J. Binkhorst CD, Gobin MH: Injuries to the eye with lens opacities in children. Ophthalmologica (Basel) 148:169, 1964

2. Strampelli B: Sopportabilita di lenti acriliche in camera anteriore nella afachia e nei vizi di refrazione. Atti Soc of tal Lombarda 8:292, 1953

3. Choyce DP: Correction of uni-ocular aphakia by means of anterior chamber acrylic implants . Trans Ophthalmol Soc UK 78:459, 1958

4. Choyce DP: Acta Can cilium Ophthalmologicum. Brussels, Belgica, 1958, vol 2, pp 1705 & 1707

5. Choyce DP: Intra-ocular L enses and Implants. London, HK Lewis, 1964, p 137

6. Choyce DP: The development and uses of all-acrylic anterior chamber implants. Trans Ophthalmol Soc UK 80:209, 1960

INDUCED RHODOPSIA TEST

To the Editor: Summarized below is the protocol for an in­

duced rhodopsia test to diagnose subclinical cystoid macular edema (CME). I have not had the oppor­tunity for extensive clinical evaluation of this test and would be interested in knowing whether it can be usefully applied to the early diagnosis of macular involvement in various implant cases.

While in a dark room, the patient observes an illuminated white projection screen in the distance. The patient is asked to cover his implanted eye; the nonimplanted eye is briefly illuminated with a pocket­light held in the visual axis close to the pupil. The patient is asked to observe the color of the screen a few moments after this overexposure of the macula to a pocket-light.

The same procedure is repeated on the implanted eye, using the same exposure time.

The patient is then asked to com pare the color of the screen as seen with his normal versus his im­planted eye. Any indication that the white color of

the screen has shifted to a slight or even obvious pink is a clinical sign of cystoid macular edema.

This induced rhodopsia can be absent with manifest cystoid macular edema of longer standing. It is therefore only used for early detection of edema­tous changes in and around the macula and in fact can indicate the presence of cystoid macular edema even when visual acuity is still 20120.

I have used this test to monitor the effect of indo­methacin drops,1.2 finding that it will indicate the favorable effect of indomethacin even in cases of very slight cystoid macular edema. Rhodopsia will disap­pear in a few days with indomethacin drops adminis­tered six times daily.

I have also found this diagnostic test significant for bilateral implant cases which have had intracap­sular surgery on one eye and extracapsular surgery on the other eye. Even when post-op vision in each eye was 20/ 20, intracapsular eyes showed a tendency towards induced rhodopsia, indicating that the macula is more vulnerable in intracapsular as com­pared to extracapsular surgery.

J.G.F. Worst Haren, Holland

REFERENCES

l. Miyake K: Prevention of cystoid macular edema after lens extraction by topical indomethacin (I), a preliminary report. Albrecht lion Graefes Arch Klin Ophthalmol 203:81, 1977

2. Miyake K: Prevention of cystoid macular edema after lens extraction by topical indomethacin (II), a control study in bilateral extractions. fpn f Ophthalmol 22:88, 1978

LENS HOLDERS

To the Editor: I have been using lens holders in implant sur­

gery for four years without problems. Recently, I purchased a Park intraocular lens holder from Storz Surgical Company. The second time I used this particular lens holder, however, I had trouble with the locking mechanism. After grasping the lens, placing it in the eye and clipping it into position, I found that when I released my grip the lens holder locking mechanism would not unlock. Al though I manipulated my hands in almost every position possible, the lens holder would not release the lens. Finally the lens disengaged itself from the lens holder spontaneously and I was able to withdraw the lens holder still in a locked position. I worked with the lens holder for a few seconds after this, unlocking it only after exaggerated sideways movements.

AM INTRA-OCULAR IMPLANT SOC J-VOL. V, APRIL 1979 147

We had tested the lock several times on the first case and had experienced no difficulty. When the difficulty did arise, it left me in a very dangerous situation. I subsequently purposely destroyed the locking mechanism of the forceps .

David B. Davis II, M.D. Hayward, CA

Storz replies: Storz Instrument Company was certainly con­

cerned to read of the difficulty Dr. Davis experienced with the Park intraocular lens holder he purchased from us. We inspect all of our instruments prior to their leaving our plant, and it is obvious that this product was in working condition when it arrived, since Dr. Davis stated that he "tested the lock several times on the first case and experienced no difficulty."

We received no product complaint from Dr. Davis and it is unfortunate that the locking mech­anism on the forceps was purposely destroyed. Since the instrument was not returned to us, we cannot presume to know what could have caused the pro­duct to fail between cases.

Steve Stephens Vice President, Product Management

IRIS A TROPHY

To the Editor: Sphincter erosion and iris atrophy in the vicinity

of the loop pegs do occur with Supramid (nylon 6) and Prolene (polypropylene)-looped lenses, although not nearly as frequently as with metal-looped lenses.

It appears to me that Prolene is somewhat rougher than Supramid and the only reason to expect sphincter damage is wi th the prolonged use of rather strong miotics. If this is avoided, and the general practice now is to avoid miotics with intraocular lenses, then the problem should be infrequent and rather mild.

Henry Hirschman, M.D. Long Beach, CA

POSTERIOR CHAMBER LENS

To the Editor: Following is a brief summary of the new Boberg­

Ans posterior chamber implant, manufactured by Rayner. This is only a preliminary report since I feel that any presentation of clinical results would be

premature prior to completion of an IS-month ob­servation period.

The posterior chamber Boberg-Ans lens re­sembles a Binkhorst 4-loop lens except that the optic is positioned behind the pupil (Fig. 1,2). The poste­rior haptic is a continuation of the optic and is slightly longer than the corresponding anterior loops (Fig. 3). The posterior haptic is angled ten degrees posteriorly and is perforated at each end to

reduce lens weight (Table I).

Fig. I (Boberg-Ans) . Anterior view of the Binkhorst 4-loop lens (Idl ) and the Boberg·Ans lens (right).

Fig. 2 (Boberg-Ans) . Side view of the Boberg-Ans lens (top) and the Binkhorst lens (bollom).

The smooth solid posterior haptic acts as a glide and protector for the vitreous while the lens is intro­duced through the pupil. The anterior loops are made slightly shorter to engage the pupillary margin

148 AM INTRA-OCULAR IMPLANT SOC J-VOL. V, APRIL 1979