FRANCESCO CARONES, MD
I would remove the wrong IOL and implant the correct one immediately. My standard implantation technique for this type of IOL involves a 2.6-mm temporalincision and injection of the IOL with a Monarch C cartridge (Alcon) in a Royale injector (ASICO, Westmont, Ill). Discovisc (Alcon) has become my routine viscoelastic for this surgery.
In order not to enlarge the original incision, I would proceed as follows. First, using a standard IOL manipulator hook, I would rotate the IOL to move it from the capsular bag into the anterior chamber. This step is quite easy, thanks to the soft and manageable loops this IOL has. Any kind of viscoelastic would therefore be suitable for protecting the endothelium.
With a modified Vannas scissors (Katena Products, Denville, NJ), I would then cut the IOL to be explanted into three pieces. During this phase, I would use a standard Buratto PMMA IOL holding forceps (Janach, Como, Italy) to firmly grasp the IOL, which tends to slip. After cutting the IOL, I would slide the pieces through the tunnel using the same forceps. I would then implant the correct IOL using my standard technique, as described earlier.
Regarding prevention, I do not store my IOLs in the OR but in an adjacent room, outside the sterile area. Usually, I select the IOL to be implanted before each patient enters the OR, where only one lens is available per case. This practice has thus far prevented the mismatching of IOLs to patients. If the IOL breaks, falls on the floor or needs to be changed, I double-check the new one.
KHIUN F. TJIA, MD
Just 2 days after I received the request to comment on this case, my first IOL mix-up error occurred (after 16 years of practice). Two women with the same surname were scheduled as my third and fourth patients. Both were undergoing cataract extraction in their right eye.
The first of these two patients was to receive the 18.00 D Acrysof SN60 IQ (Alcon), however, I implanted the 23.00 D IOL that was meant for the second patient. The circulating nurse discovered the error at the end of the procedure. Instantly, I realized that such events were inevitable (having accepted this column 2 days before).
This is how I proceeded: I enlarged the near clear corneal incision from 2.6 mm to 3.2 mm and injected Provisc (Alcon) underneath the optic of the Acrysof SN60 IQ IOL to subluxate the lens from the capsular bag. I also injected Viscoat (Alcon) above the optic to protect the corneal endothelium. I pulled the superior haptic into the wound with Macpherson forceps, introduced a Bechert fork (which I use for fast-crack phacoemulsification) underneath and in the midline of the optic and placed the Macpherson forceps on top of the optic. I spread the forceps so that both teeth were halfway between the center and edge of the optic and proceeded with a folding maneuver by pushing the forceps downward over the slim shaft of the Bechert fork.
During this folding maneuver, the IOL must be turned 90º to align it with the incision. After this, it is quite easy to pull the lens out of the eye. If you choose to fold the IOL intracamerally, enlarge the incision to approximately 3.2 mm. Folding and extracting through 2.6 mm or smaller is not advisable, however, folding an Acrysof single-piece lens is not difficult. Sensar and silicone lenses are extremely difficult to fold inside the eye. Another option is to cut the IOL with scissors or a special cheese wire-like instrument, however, I do not have either option in my standard instrument sets.
The induced astigmatism of an enlarged incision (3.2 mm) is very small. With a Restor (Alcon) implantation, however, even a small-induced cylinder may be an issue. Check the preexistent astigmatism and possibly choose a technique that will result in the best postoperative refraction.
Our procedure to check for correct lens implant in patients is completed by two nurses; it has rarely failed in the past 16 years. A recent reorganization with an almost completely new assistants' staff may have negatively influenced the outcome of my recent incorrect lens implant case. In rushing to keep up with the pace of surgery, the patients' dates of birth were not checked together with the names of the patients. Teambuilding, time and teaching will hopefully prevent future errors.
I have exchanged IOLs for many reasons. When the exchange takes place after several months, the procedure may be challenging. In this case, with the patient still in the operating theater, the exchange is relatively easy. I have successfully instructed several colleagues by telephone.
ALESSANDRO FRANCHINI, MD
With the patient still on the operating bed, I would immediately remove the lens. I would then perform a paracentesis at 180º from the main incision. After filling the capsular bag with an adhesive viscoelastic substance, I would release the IOL haptics from the bag and place them in front of the capsulorhexis and the iris plane. My next step would be to fold the lens on a spatula, insert it through the paracentesis using folding forceps, rotate the forceps and remove the lens from the anterior chamber.
Since we are dealing with a one-piece acrylic IOL, this maneuver is simple. The rounded loops are flexible and easy to handle, and they do not cause damage to the bag or to the iris. On the other hand, when dealing with other lens models, lenses that have been previously implanted or after a complicated cataract extraction, I prefer to cut the haptics in two or three pieces with modified intraocular scissors. After cutting the lens, I would remove the pieces through the incision. With either technique, after placing the correct lens in the bag with the usual maneuvers, it is important to remove the viscoelastic substance from the bag. In this case, I would refill the bag with an adhesive viscoelastic, unlike my normal practice.
Keep in mind that this particular case is quite unusual. In fact, the patient is perfectly emmetropic in the fellow eye. If the lens were not removed, the residual refractive defect would be approximately -1.50 D. Having said this, had I noticed the error after the patient had left the operating theater, I would have waited several days before deciding to remove the lens. By allowing time to pass, I could verify the patient's adoption of monovision. It could be that the patient is perfectly content with being sufficiently short-sighted and long-sighted. Undoubtedly, in this case, good functional results would be connected to other factors (eg, age, working needs, lifestyle, the dominating eye, the preoperative refraction).
To prevent this kind of incident, we carry out many controls across the preoperative phases. First, when the IOL power is calculated, the doctor who performs the biometry attaches the printed results to the clinical file. Afterward, he/she records the power of the lens chosen in a specific area of the clinical file. On the morning of the operation, the doctor who prepares the operating list records the power of the lens next to the patient's name, and the list is put up in the operating theater. Before the operation, a nurse takes the lens and stores it in a room located outside the operating area. By doing this, only the lens needed for the specific operation is present in the theater during surgery. All of the surgical material connected to each single patient is not brought into the operating room until the previous patient's surgical material has been removed. A further check is carried out by the surgeon who compares the figures recorded in the clinical file, in the operating list and on the label of the only lens present in the theater.n
Francesco Carones, MD, is cofounder and medical director of the Carones Ophthalmology Center in Milan, Italy. He has performed clinical research for and has received travel support and honoraria from Alcon. He is a member of the CRSToday Europe Editorial Board. Dr. Carones may be reached at fcarones@carones.com or +39 2 76318174
Khiun F. Tjia, MD, is an anterior segment surgery specialist at the Isala Clinics, Zwolle, Netherlands. He is a research consultant for Alcon, but he states that he holds no financial interest in any of its products. Dr. Tjia is a member of the CRSToday Europe Editorial Board. Dr. Tjia may be reached K.Tjia@Isala.nl or +31 38 424 2980.
Alessandro Franchini, MD, is a professor at the School of Ophthalmological Specialization, at the University of Florence, in Italy. He states that he holds no financial interest in the companies or products mentioned. He may be reached at alessandrofranchini@yahoo.it.
