Restoration Of Visual Function Research Articles

Functional results of surgical treatment of retinal detachment

The article analyzes the state of patients visual acuity after successful surgical treatment of retinal detachment. On the basis of gathered data, it was concluded that in case of detachment of the macula only in 50% of cases it is possible to increase visual acuity to 0.4 and higher. Restoration of visual functions continues for at least 6 months after the operation and is determined by the restoration of the structure of the outer segments of the photoreceptor cells. During this time, it is advisable to conduct drug therapy aimed at normalizing blood flow and functional activity of the retina. Visual functions recovery continues for at least 6 months after the operation and is connected with the restored structure of the outer segments of the photoreceptor cells. Important prognostic factors of central vision restoration in the postoperative period are visual acuity before surgery, duration of existence and height of macular detachment. Data on which of the methods of surgical treatment of retinal detachment allows to achieve higher visual acuity are contradictory. There is practically no data on the comparison of the effect on visual acuity of scleral buckling and vitrectomy in the long-term period, in patients with phakic eyes and with artiphakia. On visual acuity after fitting detachment of the macula may affect macular edema, epiretinal membrane formation and retinal folds, and edema of the peripapillary optic nerve head, progressive deterioration of blood flow in the basin of the central retinal artery, short posterior ciliary arteries and ophthalmic artery. It is believed that these factors are significantly more pronounced after scleral buckling than after vitrectomy. Some indicators of optical coherence tomography correlate with visual acuity after surgical treatment of retinal detachment: the state of the articulation line of the external and internal segments of the photoreceptors, as well as the state of the external limiting membrane.

Publisher Correction: Restoration of visual function in adult mice with an inherited retinal disease via adenine base editing

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Restoration of visual function in adult mice with an inherited retinal disease via adenine base editing.

Cytosine base editors and adenine base editors (ABEs) can correct point mutations predictably and independent of Cas9-induced double-stranded DNA breaks (which causes substantial indel formation) and homology-directed repair (which typically leads to low editing efficiency). Here, we show, in adult mice, that a subretinal injection of a lentivirus expressing an ABE and a single-guide RNA targeting a de novo nonsense mutation in the Rpe65 gene corrects the pathogenic mutation with up to 29% efficiency and with minimal formation of indel and off-target mutations, despite the absence of the canonical NGG sequence as a protospacer-adjacent motif. The ABE-treated mice displayed restored RPE65 expression and retinoid isomerase activity, and near-normal levels of retinal and visual functions. Our findings motivate the further testing of ABEs for the treatment of inherited retinal diseases and for the correction of pathological mutations with non-canonical protospacer-adjacent motifs.

Dexmedetomidine as an adjuvant to local anesthetics in ophthalmic surgery

Vitreoretinal surgery aims to restore the structural relationships of the posterior segment of the eye, with the possibility of partial or complete restoration of visual functions, and imposes certain requirements to the anesthetic support of operations. These are injuries, operations length, age, and concomitant pathology of organs and systems of patients. In this regard, there is a recent tendency to use different pharmacological groups as adjuvants to local anesthetics to enhance or prolong their analgesic effect. Purpose to evaluate the effectiveness of dexmedetomidine as an adjuvant in retrobulbar blockades. Materials and methods. Retrobulbar block bupivacaine with dexmedetomidine at a dose of 0.25 mg/kg was performe in the 1st group (n = 22), retrobulbar block was performed with a mixture of bupivacaine in the 2nd group (n = 22). Changes in hemodynamics at the stages of surgery were evaluated. To assess the oxidative status, the evaluation of the redox coefficient (FORT/FORD) was conducted before and after the surgery. The level of comfort of the operation by the surgeon and the patient. Assessment of pain was performed by a VRS in the points. Results. In patients of the 1st group the decrease in SAD was more pronounced and persisted throughout the entire period of surgical treatment. 54.5% of patients of group 1 and 18% of group 2 had no pain 8 hours after the surgery. 82% of patients of group 2 reported moderate pain that required medication (p 0,05). In patients of group 1, it increased from 0.45 0.5 to 0.62 0.2 (p 0,005) by 37% of the initial value, in patients of group 2, it was shown to decrease by 5% (p 0,05). In group 1, the comfort of the operation was estimated by ophthalmic surgeons as satisfactory in 77.3%, and in group 2 in 54.5% (p 0,05). Conclusion. The use of dexmedetomidine as an adjuvant of local anesthetics in ophthalmic surgery provides the necessary analgesia, hemodynamic profile of the patient, antioxidant effect and affects the quality of the surgeons work, which affects the duration of operations.

Literature Review of Surgical Treatment in Idiopathic Full-Thickness Macular Hole.

PurposeTo summarize current surgical techniques for treating primary macular holes (MHs).MethodsWe reviewed publications detailing surgical approaches to primary MHs, briefly described their protocols, and outlined their results.ResultsCurrently, the technique for primary MH repair is pars plana vitrectomy, removing the posterior cortical vitreous, stripping the epiretinal membranes, and ending with intraocular gas tamponade. The evident benefit of peeling off the internal limiting membrane (ILM) was clearly shown for MHs at stages 2 to 4 by achieving an anatomical closure rate of >90%, even in large MH up to 650 µm. Newer MH surgical techniques include modification of ILM flap techniques, placing an autologous scaffolding of tissue within the hole, and cell therapy has shown to increase the closure rate of large and chronic macular holes, resulting in modest functional improvement in complicated MHs.ConclusionSince the turn of the century, the success rate of modern macular surgery has increased, even for large and chronic MHs. There seems to be no limit to novel concepts in MH surgery, which range from anatomical closure to those proposing natural restoration of visual function via stem cell therapy.

Nrn1 Overexpression Attenuates Retinal Ganglion Cell Apoptosis, Promotes Axonal Regeneration, and Improves Visual Function Following Optic Nerve Crush in Rats.

Neuritin (Nrn1) is a small highly conserved extracellular membrane protein involved in the process of neural cell survival and differentiation, axonal and dendritic growth, and synapse formation and maturation. Previous studies have demonstrated that intravitreal injection of recombinant Nrn1 as a gene therapy could alleviate retinal ganglion cell (RGC) apoptosis and promote optic nerve axon regeneration after optic nerve crush (ONC). However, the mechanism underlying the repairing effect of Nrn1 against optic never injury remains elusive. In this study, a rAAV2-mediated Nrn1 overexpression vector (AAV2-Nrn1) was applied to treat ONC through intravitreal injection for the purpose of further exploring the effect and mechanism of Nrn1 in repairing the injured optic nerve. The results showed that AAV2-Nrn1 was mainly transfected into RGCs without affecting astrocytes. Nrn1 overexpression effectively reduced RGC apoptosis and promoted optic nerve regeneration and visual function restoration as demonstrated by retinal imaging, histopathological analysis, and physiological function detection in vivo following ONC. Immunoblot assay revealed that functional molecules of Nrn1 activated the Akt1 and Stat3 pathways and inhibited the mitochondrial apoptotic pathway. The results of the present study may provide experimental evidence for further application of Nrn1 to the clinical treatment of optic nerve injury.

Repair of Retinal Degeneration following Ex Vivo Minicircle DNA Gene Therapy and Transplantation of Corrected Photoreceptor Progenitors

The authors describe retinal reconstruction and restoration of visual function in heritably blind mice missing the rhodopsin gene using a novel method of exvivo gene therapy and cell transplantation. Photoreceptor precursors with the same chromosomal genetic mutation were treated exvivo using minicircle DNA, a non-viral technique that does not present the packaging limitations of adeno-associated virus (AAV) vectors. Following transplantation, genetically modified cells reconstructed a functional retina and supported vision in blind mice harboring the same founder gene mutation. Gene delivery by minicircles showed comparable long-term efficiency to AAV in delivering the missing gene, representing the first non-viral system for robust treatment of photoreceptors. This important proof-of-concept finding provides an innovative convergence of cell and gene therapies for the treatment of hereditary neurodegenerative disease and may be applied in future studies toward exvivo correction of patient-specific cells to provide an autologous source of tissue to replace lost photoreceptors in inherited retinal blindness. This is the first report using minicircles in photoreceptor progenitors and the first to transplant corrected photoreceptor precursors to restore vision in blind animals.

Refractive results, visual quality and patient satisfaction with a new trifocal intraocular lens design

Aim: To evaluate the outcomes after bilateral implantation of a new trifocal intraocular lens (IOL).Materials and Methods: The study included patients with visually significant cataract that underwent bilateral implantation of the Acriva Trinova Sinusoidal Trifocal IOL. The preoperative corrected distance visual acuity (CDVA) and postoperative uncorrected distance visual acuity (UDVA), CDVA, uncorrected intermediate (UIVA) and near visual acuities (UNVA) along with manifest refractions were assessed at 1 month and 6 months after cataract surgery. The defocus curve and contrast sensitivity (CS) were evaluated at the 6th month visit. Patient satisfaction and incidence of dysphotopic symptoms were assessed. Results: The study enrolled a total of 60 eyes of 30 patients, 10 males and 20 females aged 61.78± 8.73 years (range, 45 to 78 years). 90% of the patients (n: 27) achieved a binocular UIVA of 0.1 LogMAR or better at the 6-month visit while, 96.7% (n:29) patients had a binocular UNVA of 0.1 LogMAR or better in the same postoperative visit. The CS results were within the the range of normality at 6 months post-surgery. 6.7% of patients reported marked halo around light sources and 3.3% reported glare that interferes with nighttime driving. 96.6% of the patients reported spectacle independence for all distances and rated their visual function and quality satisfactory at all distances. Conclusion: Bilateral implantation of the Acriva Trinova Sinusoidal Trifocal IOL seems to provide effective restoration of visual function at all distances after cataract surgery in the majority of patients. Contrast sensitivity results and low incidence of dysphotopic phenomena might be associated with high patient satisfaction.

PSEUDOEXPHOLIATIVE SYNDROME

Today, the clouding of the lens is one of the common pathology of the organ of vision. The clouding of the lens-cataract is one of the most common causes of blindness and low vision in children and adults. According to most authors, the main method of cataract treatment is surgical. In modern cataract surgery, the leading place is occupied by the most common cataract extraction method, phacoemulsification. The modern level of phacoemulsification technology made it possible to perform operations less traumatic, gave a full restoration of visual functions. It makes no sense to talk about the indications of IOL implantation, since Currently, there is a wide range of IOL models that can be implanted for all types of complicated cataracts. It is advisable to talk about contraindications, in this case, the surgeon makes a decision based on the material capabilities, experience, and perfection of the surgical technique. There are various associated syndromes in the development of cataracts. One of the syndromes that occurs in cataracts is the pseudo-excoliation syndrome. This review addresses the unresolved issues of pseudoexfoliation syndrome. The results of studies of some scientists, data analysis, clinical cases and ways to solve this problem are considered. In particular, a number of questions remain about the tactics of patient administration before and after surgical interventions. This syndrome, as far as we know, affects the development and outcome of the disease. It is sometimes difficult to diagnose pseudo-excoliation syndrome at an early stage, sometimes contradictory statements about the initial appearance of the syndrome are encountered. The issues of prevention of postoperative complications, less traumatic surgical approaches at various stages of PES remain open.

Restoration of visual function by transplantation of optogenetically engineered photoreceptors

A major challenge in the treatment of retinal degenerative diseases, with the transplantation of replacement photoreceptors, is the difficulty in inducing the grafted cells to grow and maintain light sensitive outer segments in the host retina, which depends on proper interaction with the underlying retinal pigment epithelium (RPE). Here, for an RPE-independent treatment approach, we introduce a hyperpolarizing microbial opsin into photoreceptor precursors from newborn mice, and transplant them into blind mice lacking the photoreceptor layer. These optogenetically-transformed photoreceptors are light responsive and their transplantation leads to the recovery of visual function, as shown by ganglion cell recordings and behavioral tests. Subsequently, we generate cone photoreceptors from human induced pluripotent stem cells, expressing the chloride pump Jaws. After transplantation into blind mice, we observe light-driven responses at the photoreceptor and ganglion cell levels. These results demonstrate that structural and functional retinal repair is possible by combining stem cell therapy and optogenetics.

A short term anatomical and visual outcomes of large idiopathic macular holes surgery following inverted internal limiting membrane flap technique.

Large macular holes are not uncommon among Nepalese women population causing severe visual problem. To evaluate the technique of inverted internal limiting membrane (ILM) flaps for the repairment of large macular holes. All 10 macular holes (diameter > 400 μm) were treated with pars planavitrectomy with inverted ILM flap technique. The procedure for macular hole surgerywas pars plana vitrectomy, posterior vitreous removal, internal limiting membrane(ILM) peeling with brilliant blue assisted, inverting ILM flap into macular hole, filling of the vitreous cavity with a gas bubble(C3 F8) and post-operative face-down positioning for 1 week. SD OCT images were taken preoperative and postoperative 1 month and 3 months follow up to assess the anatomical outcome of surgery and best corrected visual acuity (BCVA) was used to evaluate the functional outcome during each visit. The BCVA was recorded using the Snellen chart and was converted to the logarithm of the minimum angle of resolution (LogMAR) equivalents. All 10 eyes had complete anatomical closure. The mean age of patients was 64.3 ± 7.53 years. The mean macular hole base diameter was 1039.4 μm (663-1526μm). Mean BVCA pre-operatively was 1.29 log MAR ±SD 0.25. Post-operatively, mean BCVA was 0.925 log MAR ±SD 0.143 (p= 0.002). There were no intra operative or post-operative complications. All the patients were followed up for a period of 3months. Inverted ILM flaps is effective for closure of the large macular hole and restoration of functional vision.

Rationale for Clinical Approaches to the Use of Modern Pharmacological Neuroprotection in Patients after Endovitreal Surgery of Rheumatogenic Retinal Detachment

Background. Annual disability index among patients with rheumatogenic retinal detachment (RRD) is 2–9 %. One of the factors, causing the development of morphofunctional disorders of macula, is the change in intraocular hemodynamics. Aim: substantiation of rational timing of neuroprotection with cytoflavin depending on the prediction of visual functions after endovitreal surgery of RRD.Materials and methods. There were 21 patients (21 eyes) with RRD. A three-port vitrectomy with silicone tamponade and its subsequent removal was performed. Two groups of patients: the 1st group – 10 patients with tolerable prediction of restoration of visual functions (increasing of visual acuity to 0.4–0.2 relative units), the 2nd group – 11 people with low level of visual prognosis (increasing of visual acuity to 0.15 and lower). All patients received cytoflavin at both stages of surgery. We used laser doppler flowmetry (microcirculation index (MI) and microcirculation efficiency index (MEI)). The criteria of “sufficiency” of cytoflavin receiving was periods of recovery of MI and MEI to indexes that were not significantly different from the norm.Results. Dynamics of response of chorioretinal microcirculation at both stages of endovitreal surgery of RRD was unidirectional. At the same time, the indexes of MI and MEI under influence of cytoflavin in patients with tolerable level of visual prognosis reached maximum index at the 15th day of observation as at the stage of silicone oil tamponade and after its removal; and in patients with low level of visual prognosis only at the 25th day of observation.Conclusions. Therapy with cytoflavin neuroprotection in patients after endovitreal surgery of RRD leads to significant increase of indexes of chorioretinal blood flow. The period of cytoflavin treatment justified until achievement of the required positive dynamics of chorioretinal microcirculation depending on the level of visual prognosis: tolerable – 15 days, low – 25 days.

Clinical Analyses of Efficiency of Multicomponental, Vitreoretinal Surgery of Eye Trauma

Eye trauma is one of the leading causes of blindness and low vision in young working age people. It gives this particular group of diseases a special social significance. The absence of a universal surgical treating tactic is explained by the variety of traumatic agents and the various types of injuries. Penetrating wounds with the introduction of a foreign body, accompanied by detachment of the retina, vascular membrane, hemorrhagic and infectious complications are the most difficult in the clinical plan.Material and methods: 103 with penetrating eye injuries were operated during the period from 2015 to 2017. 29 of them were involving the introduction of foreign bodies, which were removed at different times: 18 eyes (62 %) — at 7–10 days, 8 eyes 27.5 %) — 14–28 days after injury and 3 eyes (10.3 %) — more than 1 month. In all cases, subtotal vitrectomy 25G (68.9 %) was performed, in some cases, 23-hedge vitrectomy was preferred (31 %) due to pronounced fibro-proliferative changes in the vitreous body. In the case of a foreign body impacted into the shells with dimensions greater than 4 mm, the real cavity was tamped with PFOS.Results. The adherence of the detached retina was achieved in 14 cases, adherence of the choroid — 4 cases. Uveitis was observed in 5 cases, ophthalmic hypertension in 12 patients in the early postoperative period. Hypertension was compensated by using the antihypertensive regimen. 5 patients at the time of hospitalization had a Vis = 0, the operation was of a diaphragm-preserving nature, since a foreign body that was not removed was the cause of the development of subatrophy of the eyeball in 16 % of cases. The remaining patients had stable, positive dynamics of visual functions in the postoperative period.Conclusion: Surgery tactics for extensive eye injuries are individual, and the amount of intervention depends largely on the parameters of the traumatic agent, so planned surgery is preferable to emergency because it allows for detailed preoperative examination and to get valuable information about the condition of the eye. The exceptions are injuries with symptoms of acute endophthalmitis. Multi-unit operations provide optimal conditions for the preservation of the eye as an organ and contribute to the restoration of visual functions.

Outcomes of Inverted Internal Limiting Membrane Flap Technique for Large Idiopathic Macular Holes Surgery in Patients at A Tertiary Care Hospital

Introduction: Large macular holes cause significant reduction in central visual acuity. The aim ofthe study is to find out short term anatomical and visual outcomes of inverted internal limitingmembrane flaps technique for large macular holes (base diameter>1000μm) surgery in patientsat a tertiary care hospital.
 Methods: A descriptive cross-sectional study was conducted in a tertiary care hospital fromJanuary 2018 to December 2018 after ethical clearance from the institutional review committee.The study was done in 12 patients with idiopathic macular holes (base diameter>1000μm), theywere repaired with 25 gauge pars plana vitrectomy with brilliant blue assisted large invertedinternal limiting membrane flap technique. Statistical analyses were performed using SPSS 19.0.
 Results: All twelve eyes had complete anatomical closure. Mean best corrected visualacuity preoperatively was 1.48 logMAR±0.246. The mean macular hole base diameter was1217.0±196.77μm. The mean age of patients was 68.75±4.97 years. Postoperatively,mean best corrected visual acuity was 0.978 logMAR±0.12. There were no postoperativecomplications. All the patients perceived decreased size of central scotoma.
 Conclusions: Inverted internal limiting membrane flaps for large macular holes is suitable methodfor closure of the very large hole, restoration of functional vision and decreased size of centralscotoma.

Возможности консервативных методов лечения в восстановлении зрительных функций при приобретенной миопии

Возможности консервативных методов лечения в восстановлении зрительных функций при приобретенной миопии

Research progress of optical coherence tomography combined with microperimetry in diabetic macular edema

Diabetic macular edema is the major cause of vision impairment in patients with non-proliferative diabetic retinopathy. Thickness and pathological alterations in each retina layer of diabetic macular edema (DME) patients can be performed by optical coherence tomography (OCT) device. And retinal light sensitivity at specific retinal point and fixation state can be detected by microperimetry qualitatively and quantitatively. Moreover, OCT can discover pathological anatomical changes in the retina of DME patients, thus facilitating the interpretation of the structure-function relationship in DME with combination of microperimetry results. At present, there are various therapies for DME patients, and the primary method in evaluating therapeutic efficacy is to compare the pathological changes in the retina before and after treatment by OCT. Besides, microperimetry can provide information in visual function restoration. The combined application of OCT and microperimetry has broad prospects in the diagnosis and treatment of DME patients. Key words: Tomography, optical coherence; Visual field test; Macular edema; Diabetic retinopathy/complications; Review

Еstimation of Therapeutic Effect of Endonasal Electrophorosis with Methylethylpyridinol in Partial Optic Nerve Atrophy

Purpose:to evaluate the therapeutic effect of the drug Emoxypin administered by the method of endonasal electrophoresis to patients with partial atrophy of the optic nerve (PAON).Patients and methods.The treatment was conducted in 43 patients, the average age was 53 ± 2 years, with partial optic nerve atrophy of different etiology. The main group consisted of 22 patients who received Emoxypin by endonasal electrophoresis and a comparison group of 21 people who received Emoxypin by parabulbar injections. Each patient underwent ophthalmological examination, which included: visometry, perimetry, refractometry, biomicroscopy, ophthalmoscopy, examination of visual performance, evaluation of the state of bulbar microcirculation (general conjunctival index — OCI). In addition, electrophysiological studies of the vision organ carried out: the critical frequency of flicker fusion (CSFM) and the electrical sensitivity of the eye (EF).Results. The results of statistical analysis showed the effectiveness of the drug Emoksipin for the treatment of PAON by endonasal electrophoresis and revealed improvement in visual functions: widening the field of view to white, red and green colors, reducing visual fatigue, improving electrophysiological parameters and bulbar microcirculation.Conclusion.Evaluation of the effectiveness of Emoxypin use by endonasal electrophoresis with partial optic nerve atrophy of various etiologies showed a statistically significant positive therapeutic effect (79 %) in the form of restoration of visual functions. With parabulbar injection of this medicine, as well as with endonasal electrophoresis in 81 %, the field of view was widened from 5° to 25° in various meridians, the number of relative cattle in the field of vision decreased, and in both groups, there was an improvement in visual performance. Among patients who underwent endonasal electrophoresis, no side effects were observed.

Gene Therapy Strategies to Restore ER Proteostasis in Disease.

Proteostasis alterations are proposed as a transversal hallmark of several pathological conditions, including metabolic disorders, mechanical injury, cardiac malfunction, neurodegeneration, and cancer. Strategies to improve proteostasis aim to reduce the accumulation of specific disease-related misfolded proteins or bolster the endogenous mechanisms to fold and degrade abnormal proteins. Endoplasmic reticulum (ER) stress is a common pathological signature of a variety of diseases, which engages the unfolded protein response (UPR) as a cellular reaction to mitigate ER stress. Pharmacological modulation of the UPR is challenging considering the physiological importance of the pathway in various organs. However, local targeting of ER stress responses in the affected tissue using gene therapy is emerging as a possible solution to overcome side effects. The delivery of ER chaperones or active UPR components using adeno-associated virus (AAV) has demonstrated outstanding beneficial effects in several disease models (e.g., neurodegenerative conditions, eye disorders, and metabolic diseases). Here, we discuss current efforts to design and optimize gene therapy strategies to improve ER proteostasis in different disease contexts.

Хирургическое лечение перфорации роговицы аутотканями: клинический случай

Purpose: to analyze the effectiveness of therapeutically covering cornea perforation in a cancer patient with auto conjunctiva. Material and methods. A patient with a diagnosis of cancer of the right kidney pT1N0M1, ST 4, metastasis in the left kidney and L 1-2 vertebrae; cancer rectum pT3N0M0, liver metastases in the form of a hypodense focus underwent several surgeries: radical nephrectomy of the right kidney; anterior resection of the rectum; atypical liver resection (S3, S4, S5). Over the 5-year period of treatment in an oncology hospital the patient received 48 courses of immunotherapy (the most recent session took place in June 2014). Starting from September 2014, the patient was treated for keratouveitis of both eyes. The vision of both eyes dropped drastically from 1.0 to 0.01 (uncorrected) in just 2 months. On April 6, 2015 the patient was admitted to the Ophthalmological hospital, diagnosed with corneal ulcer perforation complicated by a cataract of the right eye, corneal dystrophy of the cornea, and complicated cataract of the left eye. He was treated by covering corneal perforation with a flap of autoconjunctiva and blepharorhaphy of the right eye. Results. In the right eye, a vascularized wall-eye in the lower third of the cornea with a stable plugging effect was formed. On Sept. 24, 2015 (5.5 months after autoconjunctiva covering and blepharorrhaphy), cataract phacoemulsification with implantation of an intraocular lens in the right eye was performed (at the date of discharge, uncorrected OD vision was 0.1 not correct). On Nov. 23, 2015 the same procedure was repeated in the left eye (at discharge vis OS = 0.4 uncorrected). After 1.5 years, the vision remained stable (OD = 0.1, OS= 0,4 uncorrected). Conclusion. The clinical case demonstrates a high risk of corneal ulcer perforation in cancer patients caused by reduced immunity after chemotherapy. Eye preserving coverage of corneal perforation with an autoconjunctiva flap accompanied by blepharorhaphy showed a satisfactory result of sealing the perforation of the cornea. The vascularized wall-eye formed affected the optical part of the cornea with minimal losses, which later allowed performing a cataract extraction with the restoration of visual functions. For citation: Ivachev E.A. Surgical treatment of corneal perforation by auto tissue: a clinical case. Russian ophthalmological journal. 2018; 11 (1): 80-4. doi: 10.21516/2072-0076-2018-11-1-80-84 (In Russian).

Transepithelial corneal collagen crosslinking in patients with progressive keratoconus

To assess the effectiveness of transepithelial collagen crosslinking (CXL) in patients with keratoconus. The study involved 44 patients (44 eyes) with stage I-II progressive keratoconus. Patients were divided into two groups. The 1st group included 22 patients that had underwent transepithelial CXL. The 2nd group included 22 patients that had underwent traditional CXL. All patients of the group 2 all patients had corneal syndrome, which lasted 2-4 days. In the 1st group, 98% of the patients did not have corneal syndrome and their visual acuity (VA) was same as preoperative on the next day after the surgery. In the 2nd group, the mean level of postoperative pain was 1.7 times higher than in group 1 (p<0.05). Six months after the treatment, uncorrected VA (UCVA) in the 1st group has increased by 52%, the best corrected VA (BCVA) - by 17%, in the 2nd group UCVA increased by 53%, BCVA - by 20% (p<0.05). The demarcation line in the 2nd group was 2.2 times deeper than in the 1st group (p<0.05). Six months after the treatment in the 1st group mean K1, K2 and Km decreased by 1.5%, 2.3% and 1.7% respectively (p>0.05); in the 2nd group - by 3.6%, 3.9% and 4.1% (p<0.05) compared with the data before the surgery. One year after the treatment, mean Kmax in the 1st group decreased by 2.1%, in the 2nd group - by 3.9%. Differences with preoperative values were statistically significant only in the 2nd group. Transepitelial CXL is a safe procedure well tolerated by patients and leading to a rapid restoration of visual function. Transepithelial CXL proved to have reduced effectiveness in inducing improvement in keratometric values, its effect on visual acuity was likely to be similar to that of epithelium-off CXL.