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A new method of inserting the J-loop posterior chamber lens to achieve capsular fixation and consistent centering
a new method of inserting the ] -loop posterior chamber lens to achieve capsular fixation and consistent centering John M. Graether, M.D. Marshalltown, Iowa ABSTRACT A new technique for inscrtion and horizontal positioning of the ]-loop posterior chamber lens is described. This method consistentlv centers the lens in the capsular pocket and can bc used with a sl~all pupil. It employs a new instrument, the Graether collar button iris retractor.
Key Words: intraocular lens, posterior chamber, iris retractor
The J-Ioop posterior chamber lens has several advantages for insertion after extracapsular cataract extraction. 1 However, occasional pupil capture by the edge of the lens, inadvertent rupture of the inferior zonules with lens displacement, and very frequent moderate displacement of the lens from the optical axis are shortcomings of this design. Most of these problems can be avoided by placing both loops of the lens within the capsular bag, preferably in the lateral capsular pockets. Such horizontal positioning centers the lens, places equal pressure on the J-Ioops, and eliminates the hardware at the 12-0'clock position so that a capsulotomy can be done through the pupil rather than through the iridectomy. I have developed a two-instrument lens insertion technique using a collar button iris retractor* (Fig. 1) to position the J -loops horizontally in the capsular bag. The method is essentially independent of pupil size and ci:m be repeated if desired loop location is not achieved on the first or subsequent attempts.
SURGICAL TECHNIQUE Prior to cataract extraction, a Kelman cystotome is used to create a W-type capsulotomy with a reference flap at 6 o'clock. This flap identifies the anterior capsule even when the pupil becomes miotic. Lens contents are removed either by phacoemulsification or extracapsular extraction and the wound is then enlarged or reduced to about 7 mm. A Sheets glide is inserted into the inferior capsular pocket. If positioning the glide in the pocket proves difficult, the collar button iris retractor can be slid along the glide to retract the iris towards 6 o'clock and reveal the inferior capsular flap.
*
Amilable from Katena products (Catalog K-3-490 or K-3-492 [irrigating model}) .
Reprint requests to Dr. Graether, The Wolfe Clinic, P.C., 309 East Church Street, Marshalltown, fA 50158. 70
Fig. 1 (Graether). Irrigating (top) and nonirrigating (middle) models of the collar button iris retractor. Enlarged view of retractor tip (bottom) shows the undersurface of the collar button which is roughened for capsule polishing. The smooth contours of this instrument minimize trauma.
The posterior chamber lens is then slid along the glide so that its inferior J-Ioop enters the inferior capsular pocket. A Sinskey hook placed in the superior optic hole (Fig. 2A) stabilizes the lens and pushes it inferiorly (Fig. 2B). The Sheets glide is then gently withdrawn from the eye and the collar button iris retractor is inserted on its side and rotated into a position beneath the iris at the junction of the lens body and the outer surface of the superior lens loop (Fig. 2C). The lens is held in position with the Sinskey hook while the collar button retractor pulls superior iris along the superior loop towards the 12-0'clock position (Fig. 2D). The superior loop is then compressed by a slight inferior lateral motion of the retractor, bringing the loop tip across the anterior lens face (Fig. 2E). A slight clockwise axial rotation of the collar button retractor guides the loop along the posterior capsule into the capsular pocket (Fig. 2F). Superior iris is retracted again to ascertain the exact location of the superior loop (Fig. 2G). If the loop is not properly positioned in the pocket, it is rebent and repositioned. The superior hole then becomes the center of rotation as the collar button retractor is placed against the inner surface of the superior loop to rotate the lens clockwise into the horizontal pockets (Fig. 2H). The retractor is positioned against the upper edge of the lens body as the Sinskey hook is removed from the hole. A peripheral iridectomy is performed and the
AM INTRA-OCULAR IMPLANT SOC J-VOL. 7, JANUARY 1981
A
B
E
F
R C
0
G
H
Fig. 2 (Graethe r). Insertion of a J-Ioop posterior chamber lens using the collar button iris retractor.
wound sutured. In most cases a posterior capsulotomy is done with a 30-gauge needle passed through the pupil, as advocated by Simcoe. 2 Usually the posterior chamber lens will completely cover the capsular opening and prevent forward migration of th e vitreous .
DISCUSSION Constant control of the lens by the .Sinskey hook prevents forward movement of the lens against the cornea even if there is some vitreous pressure. However, if vitreous pressure is marked the maneuvers can be done under a bubble of air. Once the le ns is positioned behind the iris, it cannot move forward and touch the cornea unless the pupil is very widely dilated. The presence of striae between the extremities of the J-Ioops indicates that the le ns is properly positioned in the capsular bag. I use a lens with a 0.3 -mm positioning hole and 5-0
(0.15 mm) polypropylene loops. Larger (0.5-mm) holes encroach unnecessarily into the optical portion of the lens and are more likely to permit herniation of vitreous. In addition , the Sinskey hook fits more securely in the 0.3-mm hole and cannot inadvertently slip through th e hole to endanger the posterior capsule. The 5-0 polypropylene loops Hex easily and can be safely placed entirely within the capsule . I have used this technique in over 200 consecutive posterior chamber lens insertions with only one significant displacement - due to a tear in the posterior capsule which was not recognized at the time of the operation.
REFERENCES
1. Shearing SP: A practical posterior chamber lens . Contact and
Intraocular Lens MedJ 4(3): 114, 1978 2. Simcoe CW: Capsular discission behind posterior chamber lens. Ophthalmol Times 4(9): 74, 1979
AM INTRA-OCULAR IMPLANT SOC J-VOL. 7, JANUARY 198 1
71
Key Words: intraocular lens, posterior chamber, iris retractor
The J-Ioop posterior chamber lens has several advantages for insertion after extracapsular cataract extraction. 1 However, occasional pupil capture by the edge of the lens, inadvertent rupture of the inferior zonules with lens displacement, and very frequent moderate displacement of the lens from the optical axis are shortcomings of this design. Most of these problems can be avoided by placing both loops of the lens within the capsular bag, preferably in the lateral capsular pockets. Such horizontal positioning centers the lens, places equal pressure on the J-Ioops, and eliminates the hardware at the 12-0'clock position so that a capsulotomy can be done through the pupil rather than through the iridectomy. I have developed a two-instrument lens insertion technique using a collar button iris retractor* (Fig. 1) to position the J -loops horizontally in the capsular bag. The method is essentially independent of pupil size and ci:m be repeated if desired loop location is not achieved on the first or subsequent attempts.
SURGICAL TECHNIQUE Prior to cataract extraction, a Kelman cystotome is used to create a W-type capsulotomy with a reference flap at 6 o'clock. This flap identifies the anterior capsule even when the pupil becomes miotic. Lens contents are removed either by phacoemulsification or extracapsular extraction and the wound is then enlarged or reduced to about 7 mm. A Sheets glide is inserted into the inferior capsular pocket. If positioning the glide in the pocket proves difficult, the collar button iris retractor can be slid along the glide to retract the iris towards 6 o'clock and reveal the inferior capsular flap.
*
Amilable from Katena products (Catalog K-3-490 or K-3-492 [irrigating model}) .
Reprint requests to Dr. Graether, The Wolfe Clinic, P.C., 309 East Church Street, Marshalltown, fA 50158. 70
Fig. 1 (Graether). Irrigating (top) and nonirrigating (middle) models of the collar button iris retractor. Enlarged view of retractor tip (bottom) shows the undersurface of the collar button which is roughened for capsule polishing. The smooth contours of this instrument minimize trauma.
The posterior chamber lens is then slid along the glide so that its inferior J-Ioop enters the inferior capsular pocket. A Sinskey hook placed in the superior optic hole (Fig. 2A) stabilizes the lens and pushes it inferiorly (Fig. 2B). The Sheets glide is then gently withdrawn from the eye and the collar button iris retractor is inserted on its side and rotated into a position beneath the iris at the junction of the lens body and the outer surface of the superior lens loop (Fig. 2C). The lens is held in position with the Sinskey hook while the collar button retractor pulls superior iris along the superior loop towards the 12-0'clock position (Fig. 2D). The superior loop is then compressed by a slight inferior lateral motion of the retractor, bringing the loop tip across the anterior lens face (Fig. 2E). A slight clockwise axial rotation of the collar button retractor guides the loop along the posterior capsule into the capsular pocket (Fig. 2F). Superior iris is retracted again to ascertain the exact location of the superior loop (Fig. 2G). If the loop is not properly positioned in the pocket, it is rebent and repositioned. The superior hole then becomes the center of rotation as the collar button retractor is placed against the inner surface of the superior loop to rotate the lens clockwise into the horizontal pockets (Fig. 2H). The retractor is positioned against the upper edge of the lens body as the Sinskey hook is removed from the hole. A peripheral iridectomy is performed and the
AM INTRA-OCULAR IMPLANT SOC J-VOL. 7, JANUARY 1981
A
B
E
F
R C
0
G
H
Fig. 2 (Graethe r). Insertion of a J-Ioop posterior chamber lens using the collar button iris retractor.
wound sutured. In most cases a posterior capsulotomy is done with a 30-gauge needle passed through the pupil, as advocated by Simcoe. 2 Usually the posterior chamber lens will completely cover the capsular opening and prevent forward migration of th e vitreous .
DISCUSSION Constant control of the lens by the .Sinskey hook prevents forward movement of the lens against the cornea even if there is some vitreous pressure. However, if vitreous pressure is marked the maneuvers can be done under a bubble of air. Once the le ns is positioned behind the iris, it cannot move forward and touch the cornea unless the pupil is very widely dilated. The presence of striae between the extremities of the J-Ioops indicates that the le ns is properly positioned in the capsular bag. I use a lens with a 0.3 -mm positioning hole and 5-0
(0.15 mm) polypropylene loops. Larger (0.5-mm) holes encroach unnecessarily into the optical portion of the lens and are more likely to permit herniation of vitreous. In addition , the Sinskey hook fits more securely in the 0.3-mm hole and cannot inadvertently slip through th e hole to endanger the posterior capsule. The 5-0 polypropylene loops Hex easily and can be safely placed entirely within the capsule . I have used this technique in over 200 consecutive posterior chamber lens insertions with only one significant displacement - due to a tear in the posterior capsule which was not recognized at the time of the operation.
REFERENCES
1. Shearing SP: A practical posterior chamber lens . Contact and
Intraocular Lens MedJ 4(3): 114, 1978 2. Simcoe CW: Capsular discission behind posterior chamber lens. Ophthalmol Times 4(9): 74, 1979
AM INTRA-OCULAR IMPLANT SOC J-VOL. 7, JANUARY 198 1
71