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.

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.

[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.

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.

Scleral ectasia in rhegmatogenous retinal detachment.

OBJECTIVE: To determine the relation between retinal tears and scleral ectasia. DESIGN: Prospective study. SETTING: University-based referral practice in Montreal. PATIENTS: Fifty-seven consecutive patients with primary rhegmatogenous retinal detachments undergoing scleral buckling surgery. Patients with a history of trauma or previous cryotherapy, laser treatment or other vitreoretinal procedures were excluded. Fifteen patients with diabetes mellitus undergoing primary vitrectomy and prophylactic scleral buckling for nonclearing vitreous hemorrhage constituted the control group. OUTCOME MEASURES: Presence of scleral ectasia, visual acuity, refractive error. RESULTS: Thirty-one of the study patients were phakic and 26 were aphakic or pseudophakic. Fifteen (48.4%) of the phakic patients were found to have scleral ectasia, compared with six (23.1%) of the aphakic/pseudophakic patients and two (13.3%) of the control patients (p < 0.05, chi 2 test). The most frequent location of ectasia was the superotemporal quadrant. Retinal tears occurred in the same quadrant as scleral ectasia in 12 (80.0%) of the phakic patients. CONCLUSIONS: Scleral ectasia may be causally related to rhegmatogenous retinal detachment in certain cases.

[Possible causes of rise of the intraocular pressure after trabeculectomy and the ways of their correction]. / Vozmozhnye prichiny povysheniia vnutriglaznogo davleniia posle trabekuléktomii i puti ikh ustraneniia.

Basing on the results of follow-up of 50 patients repeatedly operated on at the site of previous trabeculectomy, the authors recommend to stick to a certain order of surgical manipulations and stop the intervention when intraocular pressure is reduced to its normal level on the operative table. Such technique, together with the use of a viscous sponge to prevent coarse postoperative adhesions, helped achieve a stable hypotensive effect that was present for at least 2 years in the overwhelming majority of the patients operated on repeatedly.

Excision of limbal dermoids.

We reviewed the clinical files of 10 patients who had undergone excision of unilateral epibulbar limbal dermoids. Preoperatively, all of the affected eyes had worse visual acuity (P less than .02) and more astigmatism (P less than .01) than the contralateral eyes. Postoperatively, every patient was cosmetically improved. Of the eight patients for whom both preoperative and postoperative visual acuity measurements had been obtained, in six it had changed minimally (less than or equal to 1 line), and in two it had improved (less than or equal to 2 lines). Surgical complications included persistent epithelial defects (40%) and peripheral corneal vascularization and opacity (70%). These complications do not outweigh the cosmetic and visual benefits of dermoid excision in selected patients.