Refractive aspects of cataract surgery.

Cataract surgery has progressed to the point where it can now be performed so as to leave most patients emmetropic or with a predetermined amount of ametropia. The two major factors responsible for this prediction accuracy are intraocular lens power calculation and the control of surgically induced astigmatism. Recent theoretical intraocular lens power formulas are more accurate owing to their improved methods for predicting the postoperative anterior chamber depth. Additionally, there are more reliable methods for determining surgically induced astigmatism as well as methods for its control. Various combinations of wound architecture, wound closure, and astigmatic keratotomy and their effect on surgically induced astigmatism are reviewed.

Synergistic divergence: saccadic velocity analysis and surgical results.

The clinical findings are described in four patients with synergistic divergence (SD), an ocular motility disorder which is considered to be a variant of Duane retraction syndrome (DRS). Saccadic velocity studies in three patients demonstrated preserved abducting saccades in the affected eye with equally reduced amplitudes on both attempted abduction and adduction. The preserved saccades on attempted abduction of the affected eye, coupled with electromyographic evidence that shows maintenance of normal reciprocal innervation with respect to gaze on attempted abduction as dictated by Sherrington's law, strongly suggest that the abducens nerve is not necessarily absent or severely hypoplastic in this condition. One patient showed typical DRS in the contralateral eye and had a son with bilateral DRS, attesting to a possible genetic and etiologic relationship between SD and DRS. Three patients underwent strabismus surgery. Review of our surgical results and an analysis of the literature indicate that a crippling procedure to the ipsilateral lateral rectus muscle, such as extirpation, may be necessary to eliminate simultaneous abduction. Overcorrection did not occur following lateral rectus extirpation.

A review of 584 3M style 30 intraocular lens implants.

The 3M style 30 intraocular lens was introduced in January 1980 as a closed-loop, uniplanar posterior chamber lens intended for in-the-bag implantation. Between February 13, 1980, and February 28, 1982, 584 of these lenses were implanted by one of us. Except for a few lost to follow-up, these patients have now had a minimum of two years of follow-up under our care. Using a microcomputer-based data-base management system, we have generated graphic and tabular presentations of follow-up, age at time of surgery, best postoperative visual acuity, preoperative and postoperative pathology, and surgical events and complications. A brief discussion of the advantages of the in-the-bag location and the style 30 design characteristics is included. We have been able to profile, compare, and correlate numerous preoperative, operative, and postoperative parameters.

The use of an irrigating endo-illuminator for anterior vitrectomy.

Visualization of the vitreous during a closed anterior vitrectomy is difficult. We have recently begun to use an irrigating endo-illuminator in conjunction with the Ocutome to better visualize the clear vitreous during an anterior vitrectomy, and have used it in four different situations. We believe this technique is well suited to the general ophthalmologist and it is easy to learn.