Correlation of vitreous chamber depth with ocular biometry in high axial myopia.

PURPOSE: The proportion of axial length (AL) occupied by vitreous chamber depth (VCD), or VCD:AL, consistently correlates to ocular biometry in the general population. Relation of VCD:AL to ocular biometry in high myopia is not known. The purpose of this study is to evaluate the relation of VCD and VCD:AL to ocular biometry of highly myopic eyes. METHODS: This was a cross-sectional retrospective study of records of 214 myopic eyes (<-1 D SE, aged 20-40 years) attending the refractive surgery services. High axial myopia was defined as AL >26.5 mm. Eyes with posterior staphyloma and myopic maculopathy were excluded. Records were assessed for measurements of AL, central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT), white to white diameter (WTW), and vitreous chamber depth (VCD). Groups were formed based on increasing AL, while the sum of CCT, ACD, and LT was recorded as anterior segment depth (AS). The main outcome measure was the correlation of VCD and VCD:AL to ocular biometry. A comparison was also performed based on of degree of axial myopia. RESULTS: Mean age of the patients was 27.0 ± 5.2 years. VCD showed a very strong correlation with AL (R = 0.98, P < 0.001) but did not correlate to any anterior parameter. VCD:AL showed moderate negative relation with AS (R = -0.43, P < 0.001) and ACD (R = -0.3, P < 0.001), while it had a weakly negative relation with LT (R = -0.18, P = 0.006). VCD:AL showed strong negative relation (R > ~0.7) with AS in all individual groups of AL. Among anterior parameters, WTW showed the most consistent relation with ocular biometry. CONCLUSION: VCD:AL is a better correlate of ocular biometry in high myopia as compared to VCD. However, the correlation is weaker than that noted by previous studies done on the general population. Longitudinal studies of VCD:AL in the younger age group is recommended.

Evaluation of the vitreous chamber depth: An assessment of correlation with ocular biometrics.

Purpose: The mechanism of ocular growth eludes us and research on vitreous chamber depth (VCD) is lacking. The purpose of this study was to evaluate the role of VCD and its ratio to axial length (AL) in relation to ocular biometry. Methods: This retrospective study of patients planned for cataract surgery was performed at a tertiary center. Data regarding AL, anterior chamber depth (ACD), lens thickness (LT), and central corneal thickness (CCT) of 640 eyes was noted. Anterior segment (AS) was measured as sum of CCT, ACD, and LT, while VCD was calculated as the difference between AL and AS. Correlation of VCD and VCD: AL with ocular biometry was the primary outcome measure. Three groups were formed on the basis of AL and Pearson correlation coefficient (R) was applied. Results: Mean VCD was 15.38+/-1.14 mm. Mean VCD: AL was 0.66+/-0.02. VCD had a very strong relation with AL (R = 0.9, P < 0.001) only, whereas VCD: AL had a good--strong relation with AL (R = 0.5, P < 0.001), AS (R = 0.7, P < 0.001), ACD (R = 0.3, P < 0.001), and LT (R = 0.5, P < 0.001). The relation of VCD: AL with AS was very strong across all groups (R ≤ -0.8, P < 0.001 in all groups). 85% of eyes in group with AL <22 mm had VCD: AL <0.67, conversely 85% of eyes with AL >24.5 mm had VCD: AL >0.67. Conclusion: : We found VCD to have the strongest relation with AL. VCD: AL was more consistent and showed a strong relation to ocular biometry across all ALs. This suggests the possible utility of the ratio VCD: AL while evaluating ocular growth, refractive status, and myopia-related complications.

Femtosecond laser-assisted successful management of subluxated cataractous lens with vitreous in anterior chamber.

Femtosecond laser-assisted cataract surgery was performed in a case of posttraumatic cataract with six clock hours subluxation and vitreous in the anterior chamber (AC). Femtosecond laser pretreatment allowed a closed-chamber creation of corneal incisions, capsulotomy, and lens fragmentation with minimal sudden lens-diaphragm movements and zonular stress. Integrated imaging systems allowed customization of the size and position of capsulotomy and nuclear fragmentation, based on the extent and site of subluxation. Presence of vitreous in AC did not hamper femtosecond laser application. Triamcinolone-assisted vitrectomy was performed before phacoemulsification and after implanting the intraocular lens (IOL). Postoperative uncorrected visual acuity was 20/20 with a stable IOL.

Autoimmune thyroiditis and central serous chorioretinopathy may have a relation.

Autoimmune thyroiditis (AT) is an important cause of hypothyroidism, and central serous chorioretinopathy (CSCR) is an independent disease of the choroid and retina that leads to accumulation of fluid beneath the retina. While AT has been associated with multiple antibodies, CSCR is still regarded as idiopathic despite extensive research. We hypothesize a causative association between these 2 conditions on the basis of our experience of a case where both CSCR and AT presented simultaneously and depicted a parallel course. CSCR was documented with retinal imaging while AT was documented with serum antibody titers. Further, we discuss the possible mechanisms that may be involved in this intriguing association.

Small incision lenticule extraction (SMILE) techniques: patient selection and perspectives.

Refractive lenticule extraction is becoming the procedure of choice for the management of myopia and myopic astigmatism owing to its precision, biomechanical stability, and better ocular surface. It has similar safety, efficacy, and predictability as femtosecond laser-assisted in situ keratomileusis (FS-LASIK) and is associated with better patient satisfaction. The conventional technique of small incision lenticule extraction (SMILE) involves docking, femtosecond laser application, lenticule dissection from the surrounding stroma, and extraction. It has a steep learning curve compared to conventional flap-based corneal ablative procedures, and the surgical technique may be challenging especially for a novice surgeon. As SMILE is gaining worldwide acceptance among refractive surgeons, different modifications of the surgical technique have been described to ease the process of lenticule extraction and minimize complications. Good patient selection is essential to ensure optimal patient satisfaction, and novice surgeons should avoid cases with low myopia (thin refractive lenticules), difficult orbital anatomy, high astigmatism, or uncooperative, anxious patients to minimize complications. A comprehensive MEDLINE search was performed using "small incision lenticule extraction," "SMILE," and "refractive lenticule extraction" as keywords, and we herein review the patient selection for SMILE and various surgical techniques of SMILE with their pros and cons. With increasing surgeon experience, a standard technique is expected to evolve that may be performed in all types of cases with optimal outcomes and minimal adverse effects.

Long-term Functional and Anatomic Outcomes of Repeat Graft After Optically Failed Therapeutic Keratoplasty.

PURPOSE: To evaluate the functional and anatomic outcomes of repeat penetrating keratoplasty (PK) in optically failed therapeutic grafts. DESIGN: Prospective interventional case series. METHODS: All cases admitted at the apex tertiary care center for repeat keratoplasty following optically failed therapeutic PK were enrolled over a period of 1 year. Repeat optical PK was performed in all eyes. Primary outcome measures were postoperative graft clarity and visual acuity. Secondary outcome measures were complications including graft rejection, infections, failure, and secondary glaucoma. Follow-up examinations were undertaken on day 1; on day 7; at 1, 3, 6, and 12 months; and yearly thereafter. RESULTS: Thirty-two eyes underwent repeat PK with mean follow-up of 18.4 ± 8.9 months. Clear grafts were observed in 63.14% of cases 1 year after regraft, and graft survival further decreased to 50% at last follow-up. Visual acuity ≥ 20/200 was achieved in 43.8% of cases, and no case had a visual acuity of ≥ 20/40. Multivariate Cox regression analysis analyzed risk factors for regraft survival, and observed a hazard ratio of 3.56 with size of initial therapeutic graft ≥ 8.75 mm, and 10.99 with deep vascularization in 1 or more quadrants. Graft survival (P = .004), visual acuity (P = .039), and rejection rates (P = .036) were significantly better in cases with initial therapeutic graft size < 8.75 mm. Secondary glaucoma was present in 59.4% (19/32) after regrafts. CONCLUSION: Regraft after therapeutic PK is associated with suboptimal visual outcomes and long-term graft survival. Large size of initial therapeutic graft and deep vascularization adversely affect graft survival.

Pythium Keratitis Leading to Fatal Cavernous Sinus Thrombophlebitis.

PURPOSE: To report a case of Pythium insidiosum keratitis leading to fatal cavernous sinus thrombophlebitis. METHODS: Case report. RESULTS: A 70-year-old man presented with excruciating pain, redness, and diminution of vision in his left eye for 2 weeks after washing his hair with tap water. A total corneal ulcer with surrounding infiltrates and associated corneal thinning was present. Corneal scraping revealed the presence of Gram-positive cocci. KOH wet mount and in vivo confocal microscopy revealed branching hyphae. Combined antibacterial and antifungal treatment was started, but 4 days later, the ulcer showed signs of worsening with perforation for which a large therapeutic penetrating keratoplasty was done. The host cornea showed branching septate hyphae on Sabarouds Dextrose Agar. Two weeks later, the patient developed left eye proptosis with associated extraocular movement restriction. Magnetic resonance imaging of the head and orbit revealed cavernous sinus thrombophlebitis. Lid sparing partial exenteration was performed. Polymerase chain reaction revealed P. insidiosum. The patient subsequently developed a cerebrovascular attack and died of its complications. CONCLUSIONS: Ocular pythiosis may lead to cavernous sinus thrombophlebitis and can even be life threatening. Timely diagnosis and early radical surgery are of value. A high index of suspicion must be kept for P. insidiosum in cases with suspected fungal etiology not responding to conventional treatment.

Learning Curve of Small Incision Lenticule Extraction: Challenges and Complications.

PURPOSE: To describe the intraoperative complications observed during the initial learning curve of small incision lenticule extraction (SMILE) and their management. METHODS: Prospective evaluation of 100 consecutive eyes (50 patients) undergoing SMILE was performed at an apex tertiary care ophthalmic center. Patients older than 18 years with a stable refractive error ranging from -1.0 to -10.0 D myopia and up to 3.0 D astigmatism were included. Any intraoperative complications and their management were noted. Postoperative examination including visual acuity was performed on day 1, 1 week, and 1 month. RESULTS: Intraoperative difficulties observed in the initial 100 eyes included suction loss (2%), black spots (11%), opaque bubble layer (19%), epithelial defect (2%), and difficult lenticule extraction (9%). Difficult lenticule dissection and extraction was the most surgically challenging step and resulted in posterior stromal damage, anterior cap tear (1%), side-cut tears (4%), partially retained lenticule (1%), and completely retained lenticule (2%). Its incidence decreased from 16% (8/50) in the initial 50 cases to 2% (1/50) in the next 50 cases. Two eyes with completely retained lenticule were re-treated with flap-based excimer laser ablation after 3 months. Optimal visual and anatomical outcomes could be achieved, and no sight-threatening complication was observed in any case. CONCLUSIONS: The learning curve of SMILE is surgically challenging. Lenticule dissection and extraction is the most difficult step and leads to a multitude of complications. Most complications that result in delayed visual recovery are observed in the initial 50 cases.

AS-OCT as a Rescue Tool During Difficult Lenticule Extraction in SMILE.

PURPOSE: To report a case of lenticule adherent to the anterior cap during small incision lenticule extraction (SMILE) and its subsequent management aided by anterior segment optical coherence tomography (AS-OCT). METHODS: Case report. RESULTS: A 24-year-old woman presented with high myopia of -8.00 -0.50 @ 180° in the right eye and -8.00 -0.25 @ 180° in the left eye and underwent SMILE. In the right eye, difficulty was experienced in separating the lenticule from adjacent stroma. AS-OCT examination confirmed the presence of the lenticule adherent to the anterior stromal cap with the plane of dissection visible posterior to the lenticule. A Sinskey hook was used to lift off the peripheral edge of the lenticule from the anterior cap and the stripping of the lenticule was continued in a centripetal fashion until a small edge of the lenticule was rolled over. The lenticule was then completely separated from the overlying stromal cap and extracted through the side cut using forceps. Postoperative AS-OCT confirmed complete removal of the lenticule. Postoperative uncorrected distance visual acuity was 20/40 on day 1 and 20/20 on day 30 with a clear interface. CONCLUSIONS: AS-OCT-guided identification of the retained lenticule followed by Sinskey hook-assisted lenticule extraction aids in completion of the surgical procedure in the same sitting with optimal visual and anatomical outcomes. [J Refract Surg. 2017;33(5):352-354.].

Posterior segment nucleotomy for dislocated sclerotic cataractous lens using chandelier endoilluminator and sharp tipped chopper.

AIM: To describe a new surgical technique for managing dislocated sclerotic cataractous lens. METHODS: Six patients with advanced posteriorly dislocated cataracts were operated at a tertiary care centre and analyzed retrospectively. After standard 3 port 23 G pars plana vitrectomy and perfluorocarbon liquid (PFCL) injection, the dislocated white cataract was held with occlusion using phaco fragmatome and then chopped into smaller pieces with a sharp tipped chopper using 25 G chandelier endoilluminator. Each piece was emulsified individually. Following aspiration of PFCL, Fluid Air Exchange was done in all the cases and surgery completed uneventfully. RESULTS: Best corrected visual acuity (BCVA) in all the patients was better than 6/12 after one month of follow up. No serious complications were noted till minimum 6mo of follow up. CONCLUSION: Four port posterior segment nucleotomy with a chandelier endoilluminator, fragmatome and a chopper appears to be a safe, easy and effective procedure for managing dislocated sclerotic cataractous nuclei. Ultrasonic energy used and adverse thermal effects of the fragmatome on the sclera may be lesser.

Clinical outcomes of clear lens extraction in eyes with primary angle closure.

PURPOSE: To evaluate the effect of clear lens extraction (CLE) on intraocular pressure (IOP) and the anterior chamber angle in primary angle closure after laser peripheral iridotomy (LPI). SETTING: Tertiary eyecare center at a university hospital, New Delhi, India. DESIGN: Prospective case series. METHODS: The study included eyes with primary angle closure and an IOP over 25.0 mm Hg more than 8 weeks after LPI. All eyes had CLE by phacoemulsification. Absolute success was defined as an IOP less than 18.0 mm Hg without medications at 12 months. RESULTS: In 44 eyes (24 women, 20 men; mean age 57.2 years ± 4.2 [SD]), the mean preoperative IOP of 27.1 ± 1.55 mm Hg decreased to 13.2 ± 1.12 mm Hg at 12 months (P < .0001). The angle opening distance at 500 µm increased from baseline values at 0 degrees (from 0.104 ± 0.015 mm to 0.31 ± 0.013 mm) and 180 degrees (from 0.202 ± 0.008 mm to 0.412 ± 0.012 mm). The trabecular iris angle also increased at 0 degrees (from 9.3 ± 3.2 degrees to 32.7 ± 5.6 degrees) and 180 degrees (from 9.12 ± 3.2 degrees to 31.7 ± 5.6 degrees) (all P < .0001). In multivariate analysis, the preoperative IOP was the strongest determinant of IOP change (R(2) = 0.69, P < .0001). Absolute success was achieved in 38 eyes (86.3%). CONCLUSION: Clear lens extraction led to a significant reduction in IOP, a widening of the anterior chamber angle, and a reduced need for ocular hypotensive medications in eyes with primary angle closure and persistently raised IOP after LPI. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.