[Calculation of intraocular lens power in non-standard clinical situations].

Methods of intraocular lens (IOL) calculation in non-standard clinical situations have been developed and introduced. These include a formula that improves the calculation accuracy in patients with relatively short anterior-posterior axis and another method for eyes after previous radial keratotomy. A comparative clinical evaluation of the proposed methods has been performed. The results indicate good perspectives for their use in ocular surgery.

[Hypotensive efficacy of combined pathogenically oriented surgical treatment of cataract and primary open-angle glaucoma].

A new algorithm of combined surgical treatment of cataract and glaucoma was developed. It enables selection of a proper method of pathogenically oriented antiglaucomatous intervention, decreases surgical trauma, facilitates normalization of intraocular pressure and helps stabilizing the course of the disease. Another development is a modification of combined phacoemulsification and trabeculectomy ab interno, aimed at increasing visual and hypotensive results. Clinical studies showed high hypotensive efficacy of the combined pathogenically oriented surgical treatment of cataract and primary open-angle glaucoma.

[Results of combination surgical treatment for open-angle glaucoma and cataract].

The results of 257 combined, pathogenically oriented operations were analyzed in 181 patients with cataract concurrent with open-angle glaucoma (OAG). A system of pathogenically oriented combined surgical interventions was shown to be highly effective in patients with cataract concurrent with OAG. The proposed procedure for intraoperative determination of the retention of intraocular fluid allows a pathogenically oriented antiglaucomatous component of combined surgery to be chosen in patients with cataract and OAG. Increased visual acuity and stable stabilization of the glaucomatous process were achieved in all cases during a follow-up of less than 3 years.

[Determination of retention during phacoemulsification with AOL in patients with open-angle glaucoma].

Phacoemulsification is the most sparing technique of cataract removal in patients with open-angle glaucoma. The retention of intraocular fluid should be determined to choose a pathogenetically oriented antiglaucoma operation for uncompensated open-angle glaucoma (OAG). The study of the Schlemm's canal retrograde blood filling phenomenon may be a technique of the most informative value. The phenomenon was studied on 102 eyes (in 82 cases of glaucoma) during phacoemulsification, which indicated the high effectiveness and safety of the use of this intraoperative method. Its advantage is that manipulations are easy-to-use and accessible. This method is of particular value in treating patients with cataract concurrent with OAG, who are to undergo phacoemulsification with a one-stage pathogenetically oriented antiglaucoma operation.

[A new method of macrofragmentation of dense nuclei by using loop fragmentizer]. / Novyi metod makrofragmentatsii plotnykh khrustalikovykh iader s pomoshch'iu petlevogo fragmentatora.

The study results showed a principle possibility to fragmentize the most dense lens nuclei by means of a nylon cutting loop. The safety and efficiency of applying a loop fragmentizer in phacoemulsification of high-density cataract were equally demonstrated. The method advantages are conditioned by that a preliminary splitting of the nucleus into fragments without trenches being shaped cuts essentially the total capacity and duration of ultrasound impact, thus, the irrigation time and the needed volume of balance salt solution also decrease intraoperatively: it, naturally, diminishes the generally-known traumatic aftermaths of surgical intervention.

[Phacoemulsification of cataract in patients with high myopia]. / Fakoemul'sifikatsiia katarakty u patsientov s vysokoi stepen'iu miopii.

We conducted a study for the purpose of developing a phacoemulsification technique for patients with high myopia optimized for the specificity of myopic eye. The study involved 124 (165 eyes) patients with high myopia and cataract. The lens density in operated patients was of degrees II-IV according to Buratto. The anterior-posterior axis of the eyeball ranged from 26.5 to 34.00 mm. the patients were shared between the experimental (92 eyes) and control (73 eyes) groups with respect to a used surgical technique. A modified procedure was applied in the experimental groups and the basic technique was used in the control group. The time of lens extraction, the volume of used irrigation liquid and the frequency rate of intra- and postoperative complications were the criteria in efficiency evaluation. The study showed the modified surgical procedure of phacoemulsification to ensure a better visualization, to reduce the load on the lens ligamentous apparatus and to facilitate, as much as possible, manipulations made on the lens nucleus of myopic eye; it also cuts the time of cataract lens extraction, which ensures a less volume of used irrigation liquid.

[Original method of extracapsule fragmentation of the lens nucleus during phacoemulsification]. / Original'nyi metod vnekapsul'noi fragmentatsii iadra khrustalika pri fakoémulsifikatsii.

Clinical estimation of different modifications of phacoemulsification revealed the formation of the second tunnel in the nucleus for its division into quadrants in "four-quadrant phaco" increases the required duration of ultrasonography (US) and irrigation, which causes greater endothelial losses associated with the use of nuclear breakdown by means of a chopper tunnel. When the authors used their own methods of "extracapsular half-nuclei" fragmentation, endothelial losses are rather greater than those with the similar method "stop & "chop", which is associated with closer disposition of the US tip to the posterior corneal surface. At the same time nuclear breakdown by means a chapper in the capsular sac by the "stop & chop" method causes dilation of Zinn's ligaments, fraught by their rupture, particularly if latent derangement or defects of the zonular apparatus, and increases the risk of damage to the posterior capsule by the chopper.

[New modified method of phacoemulsification in lenticular subluxation]. / Modifikatsiia operatsii fakoémul'sifikatsii pri podvyvikhe khrustalika.

A new method for cataract removal by phacoemulsification in impaired lenticular joints consists in fixation during surgery of the anterior lenticular chamber along the edge of the capsulorrhexis by 4 retractor hooks and subsequent implantation of a soft intraocular lens. The operation was performed in 6 patients with cataracts of different types complicated by subluxation of the lens. The operation did not involve such complications as vitreous prolapse or displacement of the incompletely dislocated lens. All operations were finished with complete evacuation of lenticular mass and implantation of soft silicone intraocular lenses. The proposed method widens the category of patients in whom modern phacoemulsification can be used.

[Combination of phacoemulsification and implantation of soft intraocular lens: a most important new trend in surgery for cataract (first clinical experience)]. / Sochetanie fakoémul'sifikatsii s implantatsiei miagkoi intraokuliarnoi linzy kak vazhneishaia iz proiskhodiashchikh peremen v khirurgii katarakty. (Pervyi opyt avtorov po vnedreniiu v oftal'mologicheskuiu praktiku).

Sixty-seven patients with cataracts of different degree of maturity were operated on using phacoemulsification with implantation of soft IOLs through a dot self-hermetized incision. The advantages of this method over interventions with a large incision are a shorter postoperative rehabilitation (2-3 weeks), no postoperative astigmatism, low traumatism, and a lower risk of pre- and postoperative complications. Insertion of soft IOLs with injectors permits intraocular correction of vision through a dot incision used in phacoemulsification; no sutures are needed, and hospital stay is decreased to just 1-2 days.

[Service (computer) program for selecting magnifying means]. / Servisnaia (kompiuternaia) programma dlia vybora uvelichivaiushchikh sredstv.

A service program for selecting magnifying means has been developed and tried in 59 patients (110 eyes) with senile maculodystrophy and cataracts. Attempts at choosing traditional magnifiers (magnifying glasses, hyperoculars, telescopic eyeglasses, and contact lens-eyeglasses system) were made with due consideration for the focus of lesions and the anatomooptic parameters of the eye (corneal refraction, size of the anteroposterior axis, and clinical refraction). The results indicate that the proposed program helped effectively choose traditional magnifiers for the majority (81.35%) of the above patient population.

[Experimental research on the effect of radial keratotomy on th e mechanical properties of the cornea]. / Eksperimental'noe issledovanie vliianiia radial'noi keratotomii na mekhanicheskie svoistva rogovitsy.

Investigations were carried out in 4 rabbits. The right eyes of the animals were experimental, the left eyes--tentative (radial keratotomy with 8 incisions, maximum depth of the central zone--3.0 mm in diameter). Mechanical trial of isolated corneas with a scleral rim were made 6 months after surgery by means of a trial machine "Instron-1122" and a special clamping device. After trial, the specimens were investigated by a method of scanning electron microscopy. As a result of mechanical action, the rupture of the cornea in the zone of contact with the punch was recorded in all cases. In the control eyes, the area of the cornea was practically the same as the zone of the punch pressure on the cornea. In tentative eyes, the rupture was connected with keratotomy scars in all cases. The values of destructive load, transference of the punch at the moment pattern destruction and destructive tension along the punch contour were determined. The results obtained have shown that anterior radial and not crossing the limbus incisions in the cornea produce changes in mechanical characteristics of the cornea: in the sites of keratotomy scars, "conditionally" weak places of the corneoscleral coat are formed, the probability of breaks and tears of which in contusions of the increases.