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Changes in ocular anatomy and topography that occur due to congenital development anomalies are often of complex, composite nature. Such pathologies are accompanied by not only refractive errors, but also changes in eye's macrostructure. Careful analysis of the changes is necessary to better understand the clinical picture., Purpose: To study the specifics of structural and morphological changes of the eye in certain ocular congenital pathologies and in some orphan diseases using the results of three-dimensional ultrasound analysis and digital acoustic imaging., Material and Methods: The study included 60 patients (119 eyes) with congenital ocular changes, some of which are registered as independent orphan diseases, as well as with systemic manifestations including congenital changes in eye membranes, lens and the vitreous body. The examination involved three-dimensional scanning followed by digital processing of the imaging data obtained using general medical ultrasound systems Voluson 730 Pro Kretz and Voluson E8., Results: Digital ultrasound technologies significantly expand the scope of data on eye morphology in various congenital changes obtainable in vivo., Conclusion: The advantage of this investigation method is the possibility to reliably detect congenital spatially complex morphological deformations in the eye tissues, which in some cases are impossible to observe with other methods.

Aim: to investigate the contribution of various hemodynamic disturbances in magistral vessels to optic neuropathy (ON) progression and ocular tension changes in endocrine ophthalmopathy (EOP)., Material and Methods: A total of 39 patients (78 eyes) with subclinical EOP (clinical activity score, CAS ≤ 2) associated with Graves' disease (n = 32, 64 eyes) or autoimmune thyroiditis (n = 7, 14 eyes) were examined. Orbit echography was performed in all patients. Blood flow was assessed with a Voluson 730 PRO ultrasound diagnostic system ("Kretz", Austria) in triplex mode (B-scan, color Doppler flow mapping in combination with pulse-wave Doppler). Thus obtained hemodynamic parameters in ophthalmic artery, central retinal artery (CRA), central retinal vein (CRV), short posterior ciliary arteries (SPCA), and long posterior ciliary arteries (LPCA) were analyzed. To reveal the role of hemodynamic disturbances in the above mentioned vessels in ON progression and eye pressure maintenance, the patients were divided into 7 groups. Only those eyes, whose peripheral indices were increased by more than 25% of normal values and diastolic blood flow decreased by not less than 25%, were selected for further study. Intraocular pressure changes were evaluated by group mean (Mmean = M ± m mmHg), optic neuropathy progression--by the difference in group mean depth (dB) and number of scotomas between the first and the last visit (6 months of observation)., Results: In almost all types of perfusion disturbances, the resultant chronic ocular ischemia causes a decrease in IOP. The only exception, as shown, is simultaneous involvement of CRA, SPCA, and LPCA. The level of blood flow disturbance determines the severity of qualitative and quantitative changes in eyes with EOP-associated ON. The rate of ON progression directly correlates with baseline IOP values on day zero., Conclusion: Long-lasting chronic impairment of blood supply of the eyeball leads to reduction in ocular tension and progression of optic neuropathy. Combined perfusion disturbances in CRA and LPCA as well as in CRA, LPCA, and SPCA can be considered a high-risk factor, while SPCA and/or LPCA involvement--a moderate-risk factor.

Aim: to study the effects of blood rheology on ocular blood flow (OBF) parameters and estimated individual normal range of intraocular pressure (IOP)., Material and Methods: A total of 15 patients (15 eyes) taking warfarin were enrolled. Volumetric parameters and linear velocity of OBF under warfarin treatment and after its cessation were obtained by means of flowmetry (Paradigm's Blood Flow Analyzer) and color Doppler flow mapping (Voluson 730), respectively. On the basis of flowmetry results an individual normal range of IOP was calculated in all patients., Results: Pulsatile OBF does not appear to correlate with warfarin-induced changes in blood rheology (p = 0.09), however, depends on IOP fluctuations (p = 0.02). Resistance index of retinal vessels is found to rise significantly with increasing blood viscosity (p < 0.05)., Conclusion: The use of warfarin, an indirect thrombin inhibitor, has no effect on estimated individual normal range of IOP, which is crucial for glaucoma diagnosis and monitoring.

Aim: to evaluate ocular hemodynamics and informativity of estimated individual normal range of intraocular pressure (IOP)., Materials and Methods: A total of 12 patients (22 eyes) with carotid artery malfunction were examined. Ocular blood flow (OBF) and IOP were measured with Ocular Blood Flow Analyzer. Actual OBF was then compared with what is considered normal for a given axial length (AL). Individual normal range of IOP was calculated according to an original formula (described in previous publications). Doppler imaging of ocular vessels enabled blood flow velocity measurement. Morphological parameters and functional status of the retina and optic nerve were judged on automated perimetry (Octopus 900) and optical coherence tomography (Cirrus HD-OCT) findings. Statistical analyses were performed using Statistica 10 software., Results: Generally, OBF showed no correlation with the grade of carotid artery stenosis (p < 0.05), however, was significantly reduced as compared to its AL-dependent norm in patients with greater than 85% narrowing of the internal carotid artery, which can cause misestimating of their individual normal range of IOP. A negative relationship was established between the blood flow velocity in short posterior ciliary arteries and the grade of internal carotid artery stenosis (p < 0.005). Ocular blood flow deficit relative to the AL-dependent norm correlated with ophthalmic artery resistance index., Conclusion: OBF-based estimation of individual normal range of IOP is inexpedient in patients with greater than 80% carotid artery stenosis due to its possible influence on ocular hemodynamics. In most cases of less than 80% carotid artery stenosis OBF is adequate or slightly reduced as compared to its AL-dependent norm and thus, has no significant impact on estimated individual normal range of IOP.

A total of 78 patients (143 eyes) with low, medium and high degree myopia were assessed. Apart from standard ophthalmological tests, flowmetry and duplex ultrasound of ocular vessels were performed in all cases to evaluate volumetric and velocity parameters of ocular blood flow in relation to the length of anterior-posterior axis and the degree of myopia. It is found that both parameters of regional blood flow progressively decrease as the anterior-posterior axis increases.

The study enrolled 39 patients (78 orbits) with verified sarcoidosis. Acoustic analysis of pathological changes in ocular and orbital tissues was performed in all cases. A new evaluation method based on a combination of different modes of digital ultrasound techniques has been proposed. New data on intravital changes in sarcoidosis has been obtained. Formerly unknown deformities of acoustic images of the globe, lacrimal gland, vitreous, optic nerve, and ophthalmic artery, that could be recommended to ophthalmologists and other specialists studying sarcoidosis, have been identified.

Characteristics of ocular hemodynamics in ischemic optic neuropathy (ION) outcome and normal tension glaucoma (NTG), the conditions that are difficult to be differentially diagnosed, have been investigated. The study enrolled 32 patients (40 eyes) with ION outcome, 26 patients (46 eyes) with NTG, and 20 patients (32 eyes) with no ocular pathology. Besides the standard ophthalmological examination, color Doppler imaging of ocular vessels, evaluation of ocular blood flow volume and individual normal range of intraocular pressure (flowmetry) were performed in all cases. The results showed that an excess of the actual intraocular pressure (IOP) over the individual normal range was much higher in patients with NTG than in patients with ION (39% and 14.5% correspondingly). It was also found that NTG is associated with a more significant decrease of ocular blood flow volume (30.1% in average) in comparison to ION outcome (11%). In both conditions a decrease in velocity parameters of the blood flow in main ocular vessels was registered, however, ocular hemodynamics changes appeared to be more severe in patients with glaucomatous optic neuropathy. A statistically reliable correlation between volumetric and velocity parameters of ocular blood flow has been discovered.

Complex damage of ocular and orbital structures is an important manifestation of sarcoidosis. Incidence of ocular sarcoidosis varies among the different groups of patients. Nevertheless all patients should undergo specific examination of eye and orbit. Delayed diagnosis of ocular sarcoidosis and improper treatment may result in severe complications. Orbital changes should be also revealed in time and properly evaluated. These are the reasons for searching of new methods of eye and orbit examination in patients with sarcoidosis.

The paper touches upon the specific features of the anatomic structure and biophysical properties of the whole eye and its individual structural elements. The Russian and foreign sources characterizing a wide range of the biological, biochemical, and physical properties of morphological elements constituting the eyeball are analyzed. The significance of individual analyzed characteristics for the formation of a three-dimensional ultrasound image is assessed.

Early postcontusion hemodynamic disorders were studied, by analyzing the results of color Doppler mapping. The study included patients aged 10 to 45 years with moderate and severe postcontusion retinal changes and a visual acuity of 0.8 to 0.01. Color Doppler mapping was used to visualize blood flow in the ophthalmic artery, central retinal artery, and posterior short ciliary arteries. Preliminary studies revealed circulatory changes in the ophthalmic arterial system in the early postcontusion period. In severe macular and optic nerve lesions, a significant reduction in blood flow was detectable in all the vessels under study, but there was its more pronounced reduction in the central retinal artery and posterior short ciliary arteries, which directly corrected with the found retinal changes since these arteries are the only source of retinal circulation.

The paper presents data on the diagnostic use of three-dimensional (3-D) ultrasound visualization, analyzes earlier existing and new ultrasound diagnostic technologies, and shows it expedient to apply them in ophthalmologic practice. A hundred and forty-six healthy individuals and 52 patients (60 eyes) with different diseases of the eye and orbital cavity (chorioidal melanoma, facial angiomatosis, retinal detachment, vitreoretinal changes, etc.) were examined. The results of the studies and the analysis of the data available in the literature on this problem allow the authors to state that 3-D ultrasound diagnostic technologies can detect occult masses undetectable during conventional visual and ultrasound studies and define the topography of the dislocation of structurally complicated changes in the tunics of the eyeball.

An examination of 40 healthy persons (80 eyes) enabled a refinement and unification of the ultrasound techniques applicable to investigations of a. ophthalmica, a. and v. centralis retinae, a. ciliaris brevis et longae and of other orbital space vessels. Abilities of various regimes of computer-based sonography, in particular of color energy Doppler mapping, were determined in examinations of capillary choroidal plexuses and of optic-nerve portions neighboring directly on the eyeball. The possibilities of using the three-dimension ultrasound angioreconstruction in examinations of the ocular angioarchitectonics and of the retrobulbar space were evaluated.

Super-sharp gray scale image and highly sensitive digital wide-band Doppler, three-dimensional visualization of vessels in the pulsed energy Doppler mode were used in examination of the posterior segment of the eye, optic nerve, and orbital space. Twelve healthy volunteers (24 eyes) aged 25-45 years were examined. The architectonics of the optic disk and the blood filling of the arterial Zinn-Haller circle, reticular platelet, choroid, posterior long and posterior short ciliary arteries were studied. Vascular architectonics of the retrobulbar space was studied by the three-dimensional reconstruction in the energy Doppler mode and the borders of the vascular plexus round the optic nerve were defined.