The Boberg-Ans posterior chamber lens

The Boberg-Ans posterior chamber lens

the Boberg-Ans posterior chamber lens Jorn Boberg-Ans, M.D. Charlottenlund, Denmark In a previous issue of this Journal I reported preliminary results...

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the Boberg-Ans posterior chamber lens Jorn Boberg-Ans, M.D. Charlottenlund, Denmark In a previous issue of this Journal I reported preliminary results with the Boberg-Ans posterior chamber lens*. 1 The optic and posterior haptic of this lens are in one piece and are positioned behind the iris, either in the capsular bag or between the anterior hyaloid surface and the iris. The two anterior nylon 66 loops are placed in front of the iris (Fig. 1, 2). The technique of lens insertion is similar to that used for the Binkhorst-style 2-100p or 4-100p lens, except that the slight posterior inclination of the Boberg-Ans haptic makes it important to introduce this lens parallel and close to the iris plane. The glideshaped posterior haptic reduces intraocular manipulation. An iris suture may be placed through the superior anterior loop. This lens can be used with extracapsular (4-mm optic) or intracapsular (5-mm optic) techniques. The pupil should be constricted postoperatively using 1% pilocarpine once or twice a day.

r

1.5

L_

All measurements in millimetres Scale X20 RaYner Eoberg-ADs Posterior Chamber Implant Fig. 2 (Boberg-Ans). Dimensions of the Boberg-Ans lens. Bilateral perforations in the haptic decrease lens weight.

tients undergoing cataract extraction alone. The decreased incidence of anterior chamber shallowing in the pseudophakic group may be attributed to more meticulous closing of the wound rather than to the presence of a lens. Table 1. Comparison of immediate transient complications between aphakic and pseudophakic patients. One eye may have more than one complication. No. of Cases in 76 Aphakic Eyes

No. of Cases in 76 Pseudophakic Eyes*

(1976 - 79)

(1978 - 79)

4

4

5

2

0

4

0

1

Complication

Fig. 1 (Boberg-Ans). The Boberg-Ans lens.

In a series of76 patients undergoing implantation of a Boberg-Ans lens, two thirds of the eyes achieved a corrected visual acuity of 20/30 or better at follow-up times ranging from two to 17 months (mean of five months). Table 1 compares the occurrence of transient complications in this group with a group of pa*Availablefrom Rayner, Ltd., England; andfrom Coburn Professional Products, Clearwater, Florida Presented at the Third U.S. Intraocular Lens Symposium, Los Angeles, CA, March 27, 1980. Reprint requests to Dr. Boberg-Ans, 12 Ole Bruunscej, 2920 C harlottenlund, Denmark. 380

Hemorrhage Shallow anterior chamber Precipitates on endothelium or lens Endothelial corneal dystrophy

* All with

Boberg-Ans lenses

Table 2 compares early and late complications occurring in aphakic and pseudophakic groups. The incidence of vitreous around the lens is probably due to incarceration of semi-fluid vitreous between the edge of the lens and the pupil. This was not associated with evidence of other complications, however it prompted me to increase the diameter of the optic to

AM INTRA-OCULAR IMPLANT SOC J-VOL. 6, OCTOBER 1980

Table 2. Comparison of early and late complications between aphakic and pseudophakic patients. One eye may have more than one complication. No. of Cases in 76 Aphakic Eyes Complication

(1976 - 79)

Iritic reaction Lens dislocation Increased intraocular pressure Vitreous strands in the anterior chamber Vitreous opacities Fluid vitreous Vitreous prolapse Wound rupture Transient macular edema Choroidal detachment Endothelial corneal dystrophy Iris pigment atrophy Anterior chamber flattening Macular degeneration Retinal de tachment

No. of Cases in 76 Pseudophakic Eyes (1978 - 79)

7

14 3

5*

2

1 1 6 2 0

0 0 0 12 1

1 3

2 0

0 0

0

0 1 1

0 5 1

1

* One case required surgical intervention .

insertion of posterior chamber lenses using a modified duck-billed forceps Guy E. Knolle, Jr. , M D . . Houston , Texas

I have modified the Shepard duck-billed forceps by placing a p egimmediately behind the bill of the upper blade. This peg is used to compress the superior loop of posterior chamber lenses during implantation. The modified duck-billed forceps * is most conveniently used with the Sheets-style lens .. The forceps grasp the lens in its container (Fig. 1). With the superior lens loop compressed, the lens is passed along the Sheets glide through the pupil. After the lower loop and inferior portion of the optic enter the inferior capsular bag (Fig. 2A), the glide is withdrawn. The long elbow and then the short elbow of the superior loop are passed through the pupillary aperture using a side-to-side motion of the forceps (Fig. 2B). After the compressed loop is behind the iris, the forceps and lens are moved superiorly. This peaks the pupil around the forceps in the 12-0'clock position, thus tautening the iris sphincter and preventing the loops from returning to the anterior chamber (Fig. 2C). As the forceps is gradually removed from the eye

5 mm for intracapsular cataract extraction, reserving the 4-mm optic for extracapsular cataract extraction or secondary implantation. Five pseudophakic eyes had macular degenerative changes which mayor may not have been aggravated by the presence of a lens . Although I recommend using at least one suture to prevent lens dislocation, use of the transiridectomy suture technique with the flat posterior haptic of this lens increases the chance of vitreous loss over that associated with the Binkhorst 4-loop lens. I routinely use a single iris suture at the 12-o'clock position , tied loosely to allow the lens to move fre ely with the pupil. 1. Boberg-Ans

plant Soc J

REFERENCE Posterior chamber lens. Am Intra-Ocular Im5:148, 1979

J:

Fig. l(Knolle). The pcg of the modified forceps pushes the Sheetssty'le lens against its container, compressing the loops. As the forceps blades close on the optic, the peg prevents the upper loop from expanding. Inset: Side-view offorceps grasping the optic and superior loop. *Available from Katena Products, Inc ., East Hanover, New Jersey Reprint requests to Dr. Knolle, 12 Oaks TOlcer , #1700, Houston , TX 77027. AM INTRA-OCULAR IMPLANT SOC J-VOL. 6, OCTOBER 1980

381