Surgical and Immunohistochemical Outcomes of Scleral Reconstruction with Autogenic, Allogenic and Xenogenic Grafts: An Experimental Rabbit Model.

Purpose: Choukroun's platelet-rich fibrin (PRF), a second-generation platelet concentrate, has unique morphological and chemical features and may be considered as a scaffold for scleral reinforcement and regeneration. The purpose of this study was to compare the use of xenogenic human-derived amniotic membrane (HAM), allogenic sclera, and autogenic PRF in rabbit lamellar scleral defect model with respect to both anatomical and immunohistochemical improvement. Methods: A total of 45 adult New Zealand rabbits were randomized into five groups: normal control; without surgical procedure, negative control; scleral defect model (SDM), xenogenic HAM; SDM+HAM graft, allogenic sclera; SDM+allogenic sclera graft, autogenic PRF; SDM+autogenic PRF graft. Clinical findings, Hematoxylin&Eozin (HE), Masson Trichrome, Verhoeff Acid Fuchsin, Transforming Growth Factor ß Receptor 1, Fibroblast Growth Factor, Bone Morphogenetic Protein 2, collagen type 1, aggrecan, and Matrix Metalloproteinase 2 were evaluated. Results: Ocular surface inflammation was significantly lower in normal control and autogenic PRF groups (p < .001). Graft was avascular and not integrated to scleral wound area in 25% rabbits of allogenic sclera group (p = .02), was out of the scleral wound in 33.3% rabbits of xenogenic HAM group (p > .05), all the grafts were at the normal location and viable in autogenic PRF group. The inflammation and vascularization in autogenic PRF group was significantly lower than negative control and xenogenic HAM groups in HE (p < .001). The collagen score of negative control and xenogenic HAM groups were significantly lower than normal control (p < .001) and autogenic PRF (p < .001) groups. There were insignificant differences between allogenic sclera and autogenic PRF groups (p > .05). For immunohistochemistry, the closest values to normal control group were detected in autogenic PRF group for all immunomarkers. Conclusion: Autogenic PRF showed superior features via its excellent anatomical and chemical composition for scleral regeneration when compared to single-layered xenogenic HAM and allogenic sclera grafts.

Investigation of scleral thermal injuries caused by ultrasonic pars plana phacoemulsification and aspiration using pig eyes.

PURPOSE: The purpose of this study was to investigate the thermal injuries caused by ultrasonic pars plana phacoemulsification and aspiration (PPPEA) using pig eyes. METHOD: Using a 20-gauge (G) vitrectomy system (Accurus®, Fragmatome; Alcon Laboratories) in both the 'open-tip' and 'closed-tip' techniques, PPPEA was performed in pig eyes and the subsequent thermal injuries generated around the scleral wound were measured by infrared thermal imaging (thermography). Post surgery, the state of the scleral wound was observed under a microscope, and a tissue slice containing the scleral wound was then prepared and observed under an optical microscope. RESULTS: Thermography measurements revealed a slight temperature rise around the scleral wound in the open-tip case, yet a marked temperature rise in the closed-tip case. The scleral wound incision produced by the open tip was linear, while that produced by the closed tip was expanded. Histological examination revealed mild degeneration of the sclera around the wound in the open-tip case, yet marked tissue degeneration by thermal injuries in the closed-tip case. CONCLUSION: Our findings showed that in PPPEA, the temperature of the tip of a 20G vitrectomy system rapidly increases due to the closed-tip technique, thus producing obvious thermal damage to the scleral wound. In order to prevent thermal injuries to the scleral wound during PPPEA, it is important to shorten the time of ultrasonic oscillation during surgery as much as possible while the tip is occluded with nuclear fragments.

Genipin-Crosslinked Donor Sclera for Posterior Scleral Contraction/Reinforcement to Fight Progressive Myopia.

Purpose: Myopia has become a global public health problem, particularly in East Asia where myopic retinopathy has become one of the leading causes of blindness and visual impairment in the elderly population. The purpose of this study was to evaluate the efficacy of posterior scleral contraction/reinforcement (PSCR) surgery on controlling the progressive elongation of axial length of highly myopic eyes in young patients. Methods: This is a prospective self-controlled interventional case series. Forty young patients (<18-years old) with progressive high myopia received PSCR with a genipin-crosslinked donor scleral strip for one eye and the fellow eye served as concurrent control without surgery. The main outcome measurement was the change of axial length over 2 to 3 years of follow-up. Results: Immediately after the surgery, axial length was shortened and subsequently increased by 0.32 mm over the follow-up period. In contrast, axial length of the fellow eyes increased by 0.82 mm over the same period (P < 0.001, paired t-test). PSCR delayed axial elongation in eyes with or without staphyloma. No significant change of visual acuity, cornea refractive power, or retina thickness was noted between the surgery and fellow eyes. None of the patients lost visual acuity compared with the baseline. The procedure was well tolerated with only temporary corneal refractive axis shifts that recovered by the 6-month postsurgical visit. Conclusions: PSCR with genipin-crosslinked sclera is safe and effective to restrain eye globe elongation in young patients within a 2- to 3-year follow-up period.

Coexistence of Posterior Staphyloma, Retinitis Pigmentosa and Moderate Myopia.

The authors report a 22-year patient presented with night-blindness and progressive visual loss. Ophthalmologic examination included slit lamp biomicroscopy, best-corrected distance visual acuity, cycloplegic refraction, A-mode and B-mode ultrasonography, and full-field flash electroretinogram (ERG). Cycloplegic refractions were -6.00 (-1.25 x 175) dpt in the right eye and -7.00 (-1.50 x 165) dpt in the left eye. Slit lamp examination showed normal anterior segment. Fundoscopic examination revealed bone-spicule pigmentations, waxy optic disc, arteriolar narrowing and posterior staphyloma, with 5 optic disc in diameter in the right eye and 4 optic disc diameter in the left. Ocular ultrasonography confirmed staphyloma. Full-field ERG showed evidence of a generalized retinal dysfunction involving both rod and cone responses, supported the diagnosis of retinitis pigmentosa.

Posterior scleral reinforcement and vitrectomy for myopic foveoschisis in extreme myopia.

PURPOSE: To evaluate the effect of surgical posterior scleral reinforcement in extremely myopic patients (axial length ≥30 mm) with myopic foveoschisis. METHODS: The retrospective interventional case series study included patients with an axial length ≥30 mm, posterior scleral staphyloma, and myopic foveoschisis, who were treated either by posterior scleral reinforcement and 23-gauge 3-port pars plana vitrectomy (posterior scleral reinforcement group) or by vitrectomy (vitrectomy group) alone. All eyes additionally underwent cataract surgery. RESULTS: The study included 28 patients (28 eyes) with no significant (all P > 0.05) difference between the posterior scleral reinforcement group (n = 14) and the vitrectomy group (n = 14) in age, refractive error, axial length, and preoperative best-corrected visual acuity (BCVA). In addition to posterior scleral staphyloma and foveoschisis, a macular hole, a macular hole-associated retinal detachment, and a macular detachment without macular hole were present in three eyes, five eyes, and one eye, respectively in the study group and in three eyes, three eyes, and six eyes, respectively in the control group. In the study group, BCVA was significantly better after surgery than at baseline (P = 0.005) with an improvement in BCVA in 13 eyes, whereas BCVA was unchanged in 1 eye. In the control group, BCVA at baseline and at the end of follow-up did not differ significantly (P = 0.22). Gain in BCVA was marginally significantly higher in the study group than that in the control group (improvement by 0.69 ± 0.76 logMAR vs. 0.19 ± 0.54 logMAR; P = 0.05). The number of eyes with any improvement in BCVA (13 [93%] eyes vs. 11 [79%] eyes; P = 0.289) did not differ between both groups; an improvement in BCVA by more than 2 lines (10 [71%] eyes vs. 3 [21%] eyes; P = 0.009) was significantly higher in the study group than that in the control group. Anatomical success (defined as closure of macular holes and collapse of the foveoschisis) was achieved earlier in the study group (3.7 ± 3.2 months vs. 6.2 ± 3.0 months; P = 0.04). CONCLUSION: Posterior scleral reinforcement in association with vitrectomy, as compared with vitrectomy alone, was associated with a higher improvement in visual acuity in extremely myopic eyes with foveoschisis.

Posterior scleral reinforcement on progressive high myopic young patients.

PURPOSE: To evaluate the effect of posterior scleral reinforcement in controlling high myopic axial progression in young patients. METHODS: Only one eye of each patient had posterior scleral reinforcement surgery. Before surgery and at each postoperative follow-up, the best corrected visual acuity, intraocular pressure, refractive errors, indirect ophthalmoscopy, B-type ultrasonography, and IOLMASTER reflected light biometry were performed on both eyes. The changes of axial length and the changes of refractive errors from the baseline were compared between the surgery eyes and the contralateral eyes. RESULTS: Thirty patients had a mean age of 7.5 years and a mean spherical equivalent of -9.72 diopters. The mean elongation of axial length was significantly less in the surgery eye group than that in the contralateral eye group (0.75 mm vs. 0.94 mm, p < 0.0001, paired t test) after a mean follow-up of 895 days. The surgical effect was mild but maintained during the follow-up. The eyes with staphyloma gained less surgical effect when compared with the eyes without staphyloma (p = 0.0036). There was also a notable nonstatistically significant trend for younger patients to gain a larger surgical effect (p = 0.0986). CONCLUSIONS: Posterior scleral reinforcement surgery was found effective in slowing down high myopic axial progression in young patients within the study period, but the size of the effect was small. The surgical procedure is well tolerated without vision-threatening complications.

In vivo visualization of perforating vessels and focal scleral ectasia in pathological myopia.

PURPOSE: To describe focal scleral ectasia in areas of macular/perimacular patchy chorioretinal atrophy secondary to pathologic myopia. METHODS: Thirty-nine consecutive patients with pathologic myopia and chorioretinal atrophy in at least one eye, with and without focal scleral ectasia, were analyzed by infrared reflectance (IR) and/or multicolor imaging, enhanced depth imaging optical coherence tomography (EDI-OCT) (39 patients, 78 eyes), and swept source (SS)-OCT (13 out of 39 patients, 26 eyes) cross-sectional scan. RESULTS: Focal scleral ectasia was found in 12 out of 68 eyes (11 out of 39 consecutive patients, 27 females/12 males; mean age 65.7 ± 11.9 years) with macular/perimacular patchy chorioretinal atrophy, and was always observed inferior or temporal to the macula (mean 1.25 ± 0.38/eye). Focal scleral ectasia, appearing on fundus examination as a deep dark round/oval lesion with well-defined borders, was characterized on EDI-OCT and SS-OCT by an abrupt posterior bow of the sclera with different degrees of scleral schisis on its borders. The retinal pigment epithelium and the choroid were absent in all lesions. IR reflectance and multicolor imaging showed large vessels that seem to emerge from the focal scleral ectasia, and crossing the area of patchy atrophy. EDI-OCT and SS-OCT revealed retrobulbar vessels perforating the sclera at the borders/bottom of the abrupt posterior bow of the sclera (i.e., focal scleral ectasia) and running through the superficial scleral thickness for the whole extension of the atrophic area. CONCLUSIONS: We showed that perforating vessels are localized at the border/bottom of focal scleral ectasia in pathologic myopia.

[Clinical and experimental aspects of investigation of biomechanical properties of corneoscleral shell].

The article summarizes the results of long-term clinical and experimental studies on biomechanical properties of corneoscleral shell performed over the last few years in the Research Institute of Eye Diseases of the Russian Academy of Medical Sciences. A total of 2432 patients (4775 eyes) were assessed. Dynamic bidirectional pneumatic corneal applanation, dynamic pneumatic corneal impression, and elastotonometry were used for in vivo evaluation. A new method of biomechanical assessment--luminescent polariscopy--was studied experimentally. The findings allow correct judgment on biomechanical properties of fibrous tunic in norm and pathology, such as ectatic cornea, glaucoma or previous refractive surgery.

In vivo confocal microscopy of a corneoscleral epithelial cyst after spontaneous marsupialization.

PURPOSE: To report a case of an advanced corneoscleral epithelial cyst, healed by a spontaneous marsupialization and analyzed with in vivo confocal microscopy (IVCM). METHODS: A 10-year-old boy with a corneoscleral epithelial cyst, which involved the central cornea, was evaluated using IVCM (Heidelberg Retina Tomograph II with Rostock Cornea Module). RESULTS: The cyst emptied through a spontaneously formed minute opening in the anterior corneal stroma. Visual acuity, which had been fluctuating between 20/100 and hand motion, reached 20/50 and remained stable after a 7 months of follow-up. IVCM revealed a moderate haze under the apparently normal anterior stroma. The invading epithelium and highly reflective spheres, which probably are accumulation of desquamated cells and/or shed mucins, were demonstrated in the midstroma and deep stroma, reaching the depth of 125 µm from the uninvolved endothelium. CONCLUSIONS: A spontaneous collapse and healing of a corneoscleral cyst are possible. IVCM could be useful for the diagnosis and choice of the surgical treatment in the case of a recurrence.

Nodular sclerochoroidopathy simulating choroidal malignancy.

A 55-year-old man who had multiple subretinal and choroidal yellowish lesions and episcleral nodules for 1.5 years was diagnosed as having nodular sclerochoroidopathy after developing classic features of posterior scleritis with choroidal and serous retinal detachment. Long-term therapy with steroids in combination with mycophenolate mofetil resulted in regressed posterior scleritis and nodular lesions, as well as improved visual acuity. Nodular sclerochoroidopathy should be suspected in patients with subretinal and choroidal lesions and should be distinguished from choroidal neoplasm.

Long-term changes in axial length in adult eyes with pathologic myopia.

OBJECTIVE: To examine the long-term changes of the axial length in adults with high myopia. DESIGN: Open-label, consecutive, retrospective case series. METHODS: The medical records of 101 patients (184 eyes) with high myopia (myopia ≥-6 diopters or axial length ≥26.5 mm) were studied. The axial length of the eye was measured by A-scan ultrasonography. The significance of the changes in the axial length during follow-up was determined. The effects of the age, axial length, and the presence of a posterior staphyloma at the initial examination on the axial length elongation were determined. RESULTS: The mean follow-up period was 8.2 years. The median axial length increased significantly from 28.6 mm at the initial examination to 29.4 mm at the final examination in the 184 eyes. The axial length remained stable (≤1-mm difference) in 69%, whereas the axial length increased by more than 1 mm in 31% of the eyes. For these 31%, the median axial length increased by 1.55 mm. An increase of the axial length per year was significantly greater in older patients than their younger cohorts, and the increase in eyes with a posterior staphyloma was significantly greater than in eyes without a staphyloma. Multiple regression analyses showed that the axial length elongation was positively and significantly correlated with patient age at the initial examination. CONCLUSIONS: In highly myopic adult patients, the axial length continued to increase. Older individuals with posterior staphyloma were more susceptible to having a larger increase in the axial length. A progression of posterior staphyloma with increasing age is considered a key factor for the continuous increase of axial length in adults with high myopia.

Myopia: a collagen disease?

Myopia is an increasingly important public health problem in the world. Even though previous studies have strongly implicated a role of certain environmental factors such as visual near-work in myopia development, the pathogenesis of this disease still remains unclear. There is evidence showing that myopia is primarily a hereditary condition, combined with or without environmental influence or individual habitual factors. Recent research suggests that collagens in the sclera play an important role in the development of myopia. Based on a literature review after a Medline search on articles on myopia, changes in scleral collagen appeared to underlie or be associated with the pathogenetic factors (including inheritance) involved in myopia development. Therefore, we hypothesized that myopia is a disorder, in which alterations of scleral collagens may be responsible for the pathological changes found in it.

Clinical characteristics of posterior staphyloma in eyes with pathologic myopia.

PURPOSE: To determine the morphologic features (grade and type) of posterior staphylomas and to analyze the relationship between the morphologic features and the incidence of myopic macular lesions. DESIGN: Observational case series. METHODS: Two hundred and nine eyes of 108 consecutive patients with high myopia were studied. The grade of staphylomas was determined from B-scan ultrasonographic images across the optic disk. The type of staphyloma was determined by binocular funduscopy and was classified according to the criteria of Curtin. The participants were divided into two groups: younger than 50 years and 50 years and older. The long-term morphologic progression of staphylomas was analyzed in nine patients who were followed up for more than 20 years. RESULTS: Ninety percent of 209 eyes had a staphyloma. The prevalence of staphylomas and more advanced grades of staphylomas (> grade 2) were significantly higher in the older than in the younger patients. The higher grades of staphylomas were associated with more severe myopic retinal degeneration. Type II staphyloma was the most prominent overall; however, in older subjects, the incidence of type II was decreased significantly, and that of type IX was increased significantly. The eyes with type IX staphyloma tended to have more severe myopic retinal degeneration than eyes with type II staphylomas. The long-term follow-up study demonstrated a progression from type II to type IX with increasing age. CONCLUSIONS: These results suggest that the morphologic features of staphylomas worsens as the patient ages. The progression from type II to type IX probably increases the mechanical tension on the macular area of highly myopic eyes, which then leads to myopic fundus lesions.

Surgical management of scleral defects.

PURPOSE: To evaluate the results of surgical management of scleral defects using fascia lata, cornea, and sclera as graft materials. METHODS: The scleral defects of 8 patients were repaired surgically. Six had previous intraocular surgery, 1 had eye trauma, and the other had both intraocular surgery and trauma. Corneoscleral grafts were used in 3 eyes, scleral grafts in 4, and fascia lata was used in 1 eye. RESULTS: In 7 patients, we achieved the desired cosmetic and tectonic success. During the follow-up period, a recurrent defect was seen in 1 patient, and a second operation was required. CONCLUSIONS: Surgical techniques using fascia lata, corneal, and scleral grafts are effective for scleral defects.

[Deep non-penetrating sclerectomy with implant versus trabeculectomy m. Cairns four years of experience]. / Porównanie glebokiej nieperforujacej sklerektomii z implantem i trabekulektomii m. Cairnsa-- obserwacje 4-letnie.

The aim of this study is to present four years of experience with new surgery technique--deep sklerectomy with implant.

Esclerótica azul: asociaciones sistémicas de un signo oftalmológico

La presencia de una coloración azul en la esclerótica representa, con frecuencia una reducción en el espesor escleral. La uvea pigmentada subyacente se hace visible a través de la esclerótica adelgazada originando dicha coloración. Aunque puede encontrarse normalmente en algunos niños menores de tres meses, la esclerótica azul se puede asociar con frecuencia a multiples síndromes sistémicos y a anomalías oculares aisladas. En el presente artículo se revisa la fisiopatología de este hallazgo oftalmológico así como las asociaciones sistémicas más frecuentes.

Macular complications associated with posterior staphyloma.

PURPOSE: To report macular abnormalities associated with posterior staphyloma in eyes with myopia. METHODS: In a retrospective study, we surveyed 116 eyes of 58 patients with myopic refractions. Myopic fundus abnormalities are related to clinically quantified posterior staphyloma formation. RESULTS: A posterior staphyloma was present in 88 (75.9%) of 116 eyes with myopic refractions of -3 diopters or more. Best-corrected visual acuity was decreased among eyes in all staphyloma grades. Eyes with the shallowest staphyloma depth (grade 1) displayed the largest drop in visual acuity as well as the greatest frequency of choroidal neovascular membranes and hemorrhages. A linear relationship was observed between staphyloma grade and conus formation (P = .001), retinal pigment epithelial defects (P = .0001), lacquer cracks (P = .0001), and chorioretinal atrophy (P = .001). All these variables were increased in staphylomatous eyes. A significant difference in means by staphyloma grade was observed for myopic refractive error (P = .001), axial length (P = .001), and best-corrected visual acuity (logMAR, P = .0001). CONCLUSIONS: There was an unexpected high frequency of choroidal neovascular membranes, hemorrhage, and poor best-corrected visual acuity in the lower staphyloma categories. This suggests that the development of a choroidal neovascular membrane requires relative preservation of the choriocapillaris as present in eyes with less advanced stages of posterior staphyloma formation.