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This is a review of the literature on capsule contraction syndrome (CCS) in pseudophakic patients that involves severe fibrosis along the margin of the anterior capsule's opening and progressive contraction of the capsular bag. Possible causes of CCS and principles of its prevention and treatment have been analyzed.

The review covers different aspects of the impact of femtosecond laser-assisted cataract surgery on the state of the macular zone of the retina. Literature search has revealed inconsistency of the published data and indicated the need for a more detailed study of this problem.

The present review covers the use of chorioretinal photocoagulation, which is now a popular treatment for many diseases of the ocular fundus. The review includes a detailed 50-year history of the technology with account to both Russian and foreign achievements. The current state of the field is shown through Russian and foreign literature data. A particular emphasis is placed on subthreshold, pattern, and navigated techniques. Breakthrough solutions, such as optoacoustic monitoring, that ensure high precision of the procedure, maximum saving of tissues, and high therapeutic effectiveness are described.

The effect of laser treatment on ocular fundus tissues depends on quite a number of factors, mostly uncontrollable, hence, laser output parameters may vary dramatically even within the same fundus. In classical procedure ('threshold' laser coagulation), these parameters are adjusted to ophthalmoscopically visible tissue color changes at the site of coagulation. However, this method does not work with modern subthreshold techniques, that are more tissue-saving and thus, produce no immediate and visible changes in the retina. Calculation methods that are used instead are much less accurate. Photoacoustic monitoring may become a real breakthrough in this field. The method involves acoustic analysis of the response to soft and short laser pulses ('test' pulses). Heating of the target by the main therapeutic laser causes alterations in its physical properties and, consequently, the laser-induced acoustic signal. This gives us an ability to monitor the temperature and thus, to evaluate the clinical effect of coagulation despite the absence of visible changes at the site. The most promising techniques of photoacoustic monitoring that are being developed are discussed here.

The paper discusses literature data on the effectiveness of laser iridectomy in patients with primary angle-closure glaucoma. The main methods of anatomical and functional assessment and changes evaluation are reviewed.

A variety of subthreshold laser methods that enable selective and precise treatment of chorioretinal microstructures, thus decreasing the risk of negative changes in retina and choriocapillaries, is used in current ophthalmological practice. This comparative pathomorphological and histochemical study allowed characterizing structural changes and functional activity of chorioretinal cells after application of different subthreshold laser technologies.

Increase of scleral water permeability due to formation of porous structure after exposure of pulsed periodic radiation of erbium-glass optical fiber laser with wave length 1,56 pm was demonstrated in experimental study of cadaver human eyes in vitro and eyes of experimental animals (rabbits) in vivo. Simultaneous complex laser exposure of pars plana and ciliary processes results in summation of morphological changes that provide decrease of aqueous humor secretion, uveal drainage and extension of suprachoroid space. A base for new noninvasive technology of nondestructive laser exposure in glaucoma treatment is established.

A case of YAG-laser discission of a hazy host descemet membrane left in anterior chamber after endothelial keratoplasty is presented.

The history of development of cyclodestructive procedures is given, their advantages and disadvantages are discussed. Different techniques of laser use, relative and absolute contraindications to various laser cyclophotodestructive procedures are considered. Their potential complications and effecting mechanisms are discussed.

The influence of several subthreshold laser procedures on chorioretinal complex (CRC) tissues was experimentally studied in rabbits using histological and histochemical methods. Subthreshold micropulse laser radiation and transpupillar thermotherapy were found to have the most attenuated and advantageous effect on CRC structure. The feature of subthreshold laser exposure is partly reversible selective changes in CRC, that have temporary stimulating effect on cellular metabolism and local regenerative processes providing an opportunity for still viable tissues to function adequately.

15 patients with diabetic and hypertensive retinopathy are examined. Retinal vascular caliber was measured using adaptive multifocal fundus camera (AMFC), fundus camera "Topcon" TRS-NW200 and FAG. Combination of retinal vascular caliber measurement and fundus foto using AMFC in patients with ametropia and astigmatismus showed apparently lower arteriolovenular coefficient (A VC) compared with that estimated using FAG imaging. Retinal vascular caliber measurement using adaptive optics is a highly sensitive method of visualization and monitoring of early signs of diabetic and hypertensive retinopathy.

The paper analyzes the references given to papers in the Russian and foreign literature on the current methods of the early diagnosis and monitoring of vascular pathology of the eyeground. Their main merits and demerits are noted. Data on that adaptive optics and calibrometry may be used concurrently are given. This problem needs further investigation.

A new PASCAL laser photocoagulator (OptiMedica, USA) was clinically tested. A total of 38 laser interventions were performed in 38 eyes with diabetic retinopathy (n = 25), peripheral retinal dystrophy (n = 2), retinal ruptures (n = 2), hemophthalmos (n = 3), primary open-angle glaucoma (n = 5), and ectopic pupil (n = 1). An example of successful use of the new laser unit for pupilloplasty for the ectopic pupil is given.

Long-term studies using a great deal of clinical material (200 eyes) have revealed a role of iridial anatomic and structural characteristics in the choice of the optimum laser interventions in the treatment of both closed- and open-angle glaucoma. A differential approach to choosing a method for laser iridectomy, by taking into account the iridial structure in angle-closure glaucoma enables iridial coloboma to be formed in the vast majority (98.3%) of cases. Clinical studies of the efficiency of laser treatment in open-angle glaucoma have shown that the magnitude of iridial tissue dystrophy is an informative clinical sign, which makes it possible to elaborate preferable indications for both laser goniopuncture and laser trabeculoplasty.

To elucidate the extent to which contact and contactless procedures of diode laser transscleral cyclophotocoagulation (CPC) has a antihypertensive effect and a ocular tissue damaging effect, the authors have made a comparative assessment of the procedures to determine their preference. The study was conducted on an experimental material (5 Chinchilla rabbits (10 eyes)). The follow-up was 1 day to 6 months after laser interventions. The authors estimated the parameters of ocular hydrodynamics before and laser intervtntion throughout the follow-up and analyzed them with morphological changes kept in mind. The final antihypertensive effect of both contact and contactless procedures was virtually equal. However, less inflammatory changes and lower ocular damaging effect, and no additional medical manipulations for contactless diode laser CPC make it more preferable to contact CPC for clinical use.

The main factors of risk were analyzed and indications for preventive laser coagulation were specified in the paper. An approach was defined to ensure a maximally sparing surgical and stage-based laser treatment in retinal detachment, which is targeted at preventing its relapses and at improving the functional results.

Lavages of the lacrimal fluid were examined, before operation and immediately after operation, in 47 patients with diabetes mellitus and with pseudophakia in order to define the possibilities of the method of laser-correlation spectroscopy (LCS) in evaluating the semiotic nature and a severity degree of postoperative inflammation. It was found that, when the subjective symptomatology of inflammation in the LCS spectrums intensified, there was a higher contribution to the light dissemination of particles with a hydrodynamic diameter of 600 nm and more (i.e. of heavy lipoprotein complexes and of immune complexes), which were determined after a computer-based processing as a condition of primary intoxication and of immune shifts. The LCS results objectively confirmed that the degree of inflammatory changes during the early postoperative period was reliably higher in patients with a level of glycolyzed hemoglobin exceeding 9% versus patients with the above parameter being below 9%.

The role of new technologies in glaucoma treatment, related with the use of semi-conductor laser irradiation, is described. Indications for laser therapy in glaucoma of different types have been significantly enlarged. Diode laser trabeculoplasty (DLTP) is a qualitatively new surgery based on the traction and perforation components. Diode transscleral cyclocoagulation (DTCC) enabled treatment of late stages glaucoma (sub-terminal and terminal ones), which previously was not subject to laser therapy. A combined method (DLTP and DTCC) ensured, in many cases, an effective treatment of resistant and already-operated glaucoma.

We studied the possibilities of the method of photodynamic therapy (PDT) in the treatment of subretinal new-vascular membranes. The results of PDT in 28 patients (28 eyes) with subretinal new-vascular membranes of different etiologies were evaluated by using the techniques of fluorescent angiography and optic coherent tomography. A reduced membrane area was noted in 17 patients (17 eye), and an improved visual acuity was registered in 7 patients (7 eyes). The use of PDT makes it possible, in a number of cases, to prevent the reduction of visual functions and even to improve them in patients with subretinal new-vascular membranes. The use of diagnostic opportunities of fluorescent angiography and optic coherent tomography is an indispensable part belonging to the monitoring of the conducted treatment.

Experimental-and-morphological as well as physical-and-chemical changes occurring in the eye fibrous coat tissues, i.e. the cornea and sclera, at non-ablation impact of fiber laser radiation (Er-glass) with a wavelength of 1.56 mcm were analyzed. Necrobiotic or necrotic changes occur in the tissues with regard for laser radiation capacity and impact duration; subsequently, the regenerative process involving a retraction of the sclera and a flattening of the cornea takes place in the end. When the cornea is heated by fiber laser radiation with a minimally possible intensity (up to 0.3 Wt), a temporary weakening is observed in the corneal rigidity. Should it be accompanied by a simultaneous occurrence of retraction forces coming from the sclera (at its coagulation), it can be used to change, in the clinical controllable mode, the corneal curvature radius.

A new Soviet laser device for multiple-purpose ophthalmologic application is described. The design is based on neodymium-doped glass laser with radiation at a 1.06 micron wavelength in a Q-spoiled mode and YAG laser with radiation frequency doubling at a wavelength of 0.532 micron in continuous operation. Clinical potentialities of this laser design in the treatment of abnormalities of the anterior and posterior segment of the eye were studied in the treatment of 48 patients (48 eyes). The results evidence that the device is fit for coagulation as well as for mechanical destruction of tissue.