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Save the endothelium
save the endothelium David]. McIntyre, M.D. Bellevue, Washington Protection of the Endothelium in Implantation Cataract surgeons utilizing intraocular lenses recognize the critical danger to the corneal endothelium that arises during implantation procedures. A variety of surgical techniques are being considered to minimize the risk of contact between polymethylmethacralate lens parts and the endothelium. The following technique provides the surgeon a high degree of control during extracapsular implantation surgery. Instrument Preparation The intraocular lens has been selected, inspected for gross defect of form and optic, irrigated vigorously with balanced salt solution and properly ~~un~ed on the lens introduction forceps. The lrrtgat~ng spatula has been mounted on an irrigating handpIece and is supplied with filtered balanced salt solution at an appropriate pressure head of approximately 12 inches. The irrigating iris hook has been mounted on its handpiece, attached via a sterile extension set to an air filled 5 cc syringe. The entire unit is prepared and "charged" in the following fashion: (1) balanced salt solution is drawn up in the "new" 5 cc syringe. This balanced salt solution is then flushed vigorously through the assembled extension tube, handpiece and irrigating iris hook. (2) The syringe is removed, filled with air and the entire system blown free of its contained balanced salt solution. (3) Fresh intraocular carbachol is drawn up into a new 2 cc disposable syringe. 0.5 cc of the carbachol is injected from the syringe through a .22 micron filter into the asse~bled ha?dpiece, irrigating iris hook and tubing formmg a flUId column of 2 or 3 inches. (4) The 5 cc syringe is refilled with air and with very gentle pressure the column of carbachol is advanced to just expel the air remaining in the handpiece and irrigating hook. The syringe is again refilled with air and the combination laid aside for its eventual use. The remaining carbachol is injected through the filter into a disposable tuberculin syringe, mounted with a 30 gauge anterior chamber cannula and held for supplementary use. The Operative Procedure The extracapsular cataract extraction has been completed. The corneo-scleral section is approximately 1400 with sutures placed at 11:30 and 12:30
o'clock. The loops of these sutures have been extracted and laid well out over the adjacent wound ends. The cornea is then elevated with the heel of the irrigating spatula with the balanced salt solution infusion running. The Binkhorst lens is introduced in~o the an!erior c~a?Iber under the irrigation spatula (FIg. 1) WIth suffiCIent pressure against the iris to
Fig. 1 (McIntyre, D.) Insertion of lens with irrigation.
Fig. 2 (McIntyre, D.) Continued irrigation.
prevent any possible contact with the endothelium. During insertion the surgeon's hand and the intraocular lens are in constant circular motion. This minimizes drag on both the iris and the posterior lens c~psule but . perhaps more importantly, relieves tenSIon and fatIgue. When the lens is fully in the anterior chamber, (Fig. 2) the irrigating spatula follows it downwards with constant infusion maintaining the chamber volume. ~he i?ferior fixation loop is placed directly into the mfenor capsular bag. The lens is held in this inferior position by the irrigating spatula while the introduction forceps are withdrawn (Fig. 3). While the
Fig. 3 (McIntyre, D.) Inferior loop placement.
Fig. 4 (Mcintyre, D.) Superior loop placement.
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intraocular lens is held in the inferior and posterior position by the irrigating spatula, the anterior chamber is entered with the prepared irrigating iris hook. The superior iris and the superior leaflet of the anterior capsule are lifted up and over the superior lens fixation loop (Fig. 4). The assistant then, gently raises pressure in the air syringe causing infusion of the 0.5 cc of carbachol that has been prepared in the irrigating handpiece and iris hook. Continued gentle pressure on the small caliber air syringe gives the assistant excellent control in the initial insufflation of the anterior chamber (Fig. 5). Formation of the
Fig. 5 (McIntyre, D.) Airfilled chamber.
Fig. 6 (McIntyre, D.) Removal of instruments.
anterior chamber air bubble with the irrigating spatula controlling the intraocular lens in its posterior position, is an absolute preventive to the occasional but very troublesome problem of air formation behind the lens - pushing it forward into the endothelium. When the air bubble is well formed in the anterior chamber, the instruments are withdrawn (Fig. 6). First the irrigating spatula, then the irrigating iris hook. A temporary tie is immediately placed in each of the two corneo-scleral sutures and additional air or miotic is injected as required. During any necessary reformation of the air bubble, a rigorous precaution is again observed. If a major portion of the air bubble has been lost and there is significant shallowing of the anterior chamber, air is injected from the tuberculin syringe via a 30 gauge anterior chamber cannula which simultaneously controls the position of the intraocular lens. The cannula is inserted into the anterior chamber transversely across the superior fixation loop, pressing through the iris to hold the lens in its posterior position (Fig. 7). This again, is an absolute preventive for the formation of air behind the pseudophake. The wound is then permanently closed, each suture tied as it is placed. The sutures at 11 :30 and 12:30 o'clock are permanently tied after placement of all other sutures. Initial bowknot 52
closure of these two sutures allows one to maintain very nice control over the suture tension, as one tends always to obtain the least consistent tension in the first tied suture. The technique of suture placement must be as precise as possible. With the extremely sharp needles currently available, it is only necessary to steady the wound margin with the Colibri froceps as the needle is passed. Loss of the air bubble is thus minimized. In addition, where an interspace will accept 3 sutures, placement of the center stitch first will further minimize the chance of air loss. During corneo-scleral suture placement the air bubble is of course reformed as often as required, but always with careful control of the intraocular lens.
Fig. 7 (McIntyre, D.) Addition of air.
Fig. 8 (McIntyre, D.) Air removal.
At the conclusion of wound closure and after iridectomies have been accomplished, the air bubble is aspirated. Again, careful control is maintained to minimize any possible endothelial trauma. The bubble is aspirated in 2 or 3 stages through a 30 gauge anterior chamber cannula on the tuberculin syringe partly filled with balanced salt solution. After a portion of the air is aspirated (Fig. 8) the cannula is withdrawn, air expelled from the syringe, the cannula reinserted and the chamber deepened with balanced salt solution. The remaining air is then aspirated, again the air expelled from the cannula and the chamber re-deepened. We thus demonstrate at the conclusion of our operation that the wound is not only air-tight but water-tight and the eye is left with an approximately normal intraocular pressure. Summary The health of the corneal endothelium is a critical factor in the final outcome of intraocular surgery. With the advent of intraocular lens implantation, the hazard of inadvertent endothelial trauma is greatly increased. A rigorous technique has been presented which will minimize the risk of such trauma in
extracapsular cataract surgery with implantation of Binkhorst type intraocular lenses. The special instrumentation utilized in this technique is available from Sparta Instrument Corp., 305 Fairfield Ave., Fairfield, N.J. 07006.
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o'clock. The loops of these sutures have been extracted and laid well out over the adjacent wound ends. The cornea is then elevated with the heel of the irrigating spatula with the balanced salt solution infusion running. The Binkhorst lens is introduced in~o the an!erior c~a?Iber under the irrigation spatula (FIg. 1) WIth suffiCIent pressure against the iris to
Fig. 1 (McIntyre, D.) Insertion of lens with irrigation.
Fig. 2 (McIntyre, D.) Continued irrigation.
prevent any possible contact with the endothelium. During insertion the surgeon's hand and the intraocular lens are in constant circular motion. This minimizes drag on both the iris and the posterior lens c~psule but . perhaps more importantly, relieves tenSIon and fatIgue. When the lens is fully in the anterior chamber, (Fig. 2) the irrigating spatula follows it downwards with constant infusion maintaining the chamber volume. ~he i?ferior fixation loop is placed directly into the mfenor capsular bag. The lens is held in this inferior position by the irrigating spatula while the introduction forceps are withdrawn (Fig. 3). While the
Fig. 3 (McIntyre, D.) Inferior loop placement.
Fig. 4 (Mcintyre, D.) Superior loop placement.
Sl
intraocular lens is held in the inferior and posterior position by the irrigating spatula, the anterior chamber is entered with the prepared irrigating iris hook. The superior iris and the superior leaflet of the anterior capsule are lifted up and over the superior lens fixation loop (Fig. 4). The assistant then, gently raises pressure in the air syringe causing infusion of the 0.5 cc of carbachol that has been prepared in the irrigating handpiece and iris hook. Continued gentle pressure on the small caliber air syringe gives the assistant excellent control in the initial insufflation of the anterior chamber (Fig. 5). Formation of the
Fig. 5 (McIntyre, D.) Airfilled chamber.
Fig. 6 (McIntyre, D.) Removal of instruments.
anterior chamber air bubble with the irrigating spatula controlling the intraocular lens in its posterior position, is an absolute preventive to the occasional but very troublesome problem of air formation behind the lens - pushing it forward into the endothelium. When the air bubble is well formed in the anterior chamber, the instruments are withdrawn (Fig. 6). First the irrigating spatula, then the irrigating iris hook. A temporary tie is immediately placed in each of the two corneo-scleral sutures and additional air or miotic is injected as required. During any necessary reformation of the air bubble, a rigorous precaution is again observed. If a major portion of the air bubble has been lost and there is significant shallowing of the anterior chamber, air is injected from the tuberculin syringe via a 30 gauge anterior chamber cannula which simultaneously controls the position of the intraocular lens. The cannula is inserted into the anterior chamber transversely across the superior fixation loop, pressing through the iris to hold the lens in its posterior position (Fig. 7). This again, is an absolute preventive for the formation of air behind the pseudophake. The wound is then permanently closed, each suture tied as it is placed. The sutures at 11 :30 and 12:30 o'clock are permanently tied after placement of all other sutures. Initial bowknot 52
closure of these two sutures allows one to maintain very nice control over the suture tension, as one tends always to obtain the least consistent tension in the first tied suture. The technique of suture placement must be as precise as possible. With the extremely sharp needles currently available, it is only necessary to steady the wound margin with the Colibri froceps as the needle is passed. Loss of the air bubble is thus minimized. In addition, where an interspace will accept 3 sutures, placement of the center stitch first will further minimize the chance of air loss. During corneo-scleral suture placement the air bubble is of course reformed as often as required, but always with careful control of the intraocular lens.
Fig. 7 (McIntyre, D.) Addition of air.
Fig. 8 (McIntyre, D.) Air removal.
At the conclusion of wound closure and after iridectomies have been accomplished, the air bubble is aspirated. Again, careful control is maintained to minimize any possible endothelial trauma. The bubble is aspirated in 2 or 3 stages through a 30 gauge anterior chamber cannula on the tuberculin syringe partly filled with balanced salt solution. After a portion of the air is aspirated (Fig. 8) the cannula is withdrawn, air expelled from the syringe, the cannula reinserted and the chamber deepened with balanced salt solution. The remaining air is then aspirated, again the air expelled from the cannula and the chamber re-deepened. We thus demonstrate at the conclusion of our operation that the wound is not only air-tight but water-tight and the eye is left with an approximately normal intraocular pressure. Summary The health of the corneal endothelium is a critical factor in the final outcome of intraocular surgery. With the advent of intraocular lens implantation, the hazard of inadvertent endothelial trauma is greatly increased. A rigorous technique has been presented which will minimize the risk of such trauma in
extracapsular cataract surgery with implantation of Binkhorst type intraocular lenses. The special instrumentation utilized in this technique is available from Sparta Instrument Corp., 305 Fairfield Ave., Fairfield, N.J. 07006.
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