Sulcus Placement Research Articles

The triple procedure: in the bag placement versus ciliary sulcus placement of the intraocular lens

AIMSTo evaluate the influence of intraocular lens (IOL) placement on triple procedure clinical results and to investigate whether it is appropriate to use phacoemulsification in patients with large lens nucleus.METHODS40...

External Transscleral Posterior Chamber Lens Fixation-Reply

In Reply. —We appreciate Dr Friedlander's interesting and practical suggestions. In procedures described in our article and elsewhere1for external transscleral posterior chamber lens fixation, tying a 10-0 polypropylene suture to the lens haptic may indeed be a difficult maneuver for several reasons. As the polypropylene suture is tied to the lens haptic, the knot may easily slip off the haptic. We have found that a lens recently released by Alcon (Model CZ70BD, Fort Worth, Tex) has holes positioned within the haptics at an optimal site for suture lens fixation, and avoids the problem of knot slippage. The residents in our teaching program have found this lens much easier to use. This lens is also 12.5 mm in length, an ideal length for sulcus placement. As pointed out by Dr Friedlander, tying a one-ended suture may also be challenging. Our technique describes the use of a double-armed polypropylene suture

Anterior chamber depth with sulcus and capsular bag placed IOGEL lenses

The anterior chamber depth was measured in 15 eyes with sulcus placed (Group 1) and 12 eyes with bag placed (Group 2) IOGEL PC-12 lenses, and in 11 eyes with bag placed IOGEL 1103 lenses (Group 3). The mean anterior chamber depth was 3.29 mm in Group 1, 4.17 mm in Group 2, and 4.16 mm in Group 3. The difference between the mean anterior chamber depth with sulcus and bag placed IOGEL PC-12 lenses is statistically significant (P <.0005). One effect of the different anterior chamber depths was that the anterior surface of a sulcus placed IOGEL lens frequently touched the pupillary border, whereas this rarely occurred when it was placed in the capsular bag. Another effect of differing anterior chamber depths was a different A-constant for the SRK-formula for sulcus or bag placement. In this study it was about 1 diopter greater with bag fixation than with sulcus fixation. It is recommended that each surgeon use specific A-constants to enhance the predictability of the postoperative refraction.

Histologic Study of Eyes With Transsclerally Sutured Posterior Chamber Intraocular Lenses

We studied the postmortem histologic characteristics of two eyes that had undergone penetrating keratoplasty and transscleral suturing of a posterior chamber intraocular lens for bullous keratopathy. The eyes were studied three days postoperatively in a 79-year-old man with pseudophakia and six months postoperatively in an 83-year-old man with aphakia. We also removed a posterior chamber intraocular lens in a 73-year-old woman who had an epithelial downgrowth three months postoperatively. In the first two cases, only one of four haptics was successfully positioned in the sulcus. Histologic study disclosed a thin fibrous capsule surrounding the haptics at their attachment site, no inflammation around the transscleral portion of the suture, and exposure of a suture tip externally. In the third case, the intraocular lens fell back into the vitreous cavity after the fixation sutures were cut externally at the time of surgical removal. Stability of the lens in all three cases was primarily a result of intact transcleral sutures and not fibrous encapsulation or ciliary sulcus placement of haptics.

Evaluation of the biocompatibility and fixation of a new silicone intraocular lens in the feline model

The biocompatibility and fixation of a new silicone intraocular lens was evaluated in the cat eye. Following extracapsular lens extraction, 14 cats were implanted with a silicone lens (SLM 2/UV type) with polypropylene modified J loops in one eye and a poly(methyl methacrylate) (PMMA) lens (Perspex CQ of a similar design in the fellow eye. Half the lenses were placed in the ciliary sulcus and half in the capsular bag. The eyes were evaluated for up to one year. Neither lens material showed any signs of toxicity clinically or histopathologically. Both lenses achieved stable fixation in the capsular bag; however, some inflammatory reaction and lens dislocation were noted with sulcus placement of both lens types. The amount of proteinaceous and cellular debris on the explanted silicone lenses was significantly less than that on the PMMA lenses as assessed with methylene blue staining. All retrieved lenses were optically clear and no significant change in the lens surface morphology, clarity and/or optical properties was observed.

Results of the intercapsular technique with the IOGEL lens

Standard biconvex 12 mm diameter IOGEL PC-1 hydrogel intraocular lenses were inserted into the eyes of 55 patients using intercapsular in-the-hag placement and extracapsular ciliary sulcus placement. All patients had senile cataracts. Endothelial specular microscopic assessment was performed preoperatively and postoperatively at six and 12 months. Viscoelastic agents were not used in any of the cases and upper haptic positioning was achieved with dialing and irrigation and iris retraction in each group, respectively. Major complications in both groups were iridocapsular synechias. This resulted in dislocation of a single haptic into the anterior chamber angle in one ciliary-sulcus-placed lens and in an updrawn pupil in one of the intercapsular cases. Pigment dispersion syndrome occurred in one case with a ciliary-sulcus-placed lens. In one case in each group a Nd:YAG laser posterior capsulotomy was performed. Whereas the visual results in each group were similar, the percentage cell loss was significantly greater in the group with lenses in the ciliary sulcus at six months postoperatively. The lower cell loss in the intercapsular group was attributed to the protective effect of the anterior capsule on the endothelium during the major intraocular manipulations.