Eric Ezra

Factors affecting the success of nasolacrimal duct probing for congenital nasolacrimal duct obstruction

PURPOSE To ascertain the effect of certain parameters on nasolacrimal duct probing. METHODS In a retrospective study of 142 infants and children who underwent nasolacrimal duct probing for congenital nasolacrimal duct obstruction, age at time of probing, gender, symptom severity, presence of mucous discharge, and history of probing were correlated with success of nasolacrimal probing. Success of probing was defined as complete resolution of signs and symptoms of nasolacrimal duct obstruction. Chi-square test was used to analyze covariance. RESULTS Success of nasolacrimal duct probing was negatively correlated with increasing age: 92%, 89%, 80%, 71%, and 42% at age 12, 24, 36, 48, and 60 months, respectively (P = .001 at each interval). Increasing severity of epiphora was correlated with increased failure of nasolacrimal duct probing (P = .05). CONCLUSIONS Although the success of nasolacrimal duct probing declines with age, probing in older children can remain the first line of treatment. Because increasing frequency of epiphora correlates with failure of nasolacrimal duct probing, children with daily epiphora should undergo early nasolacrimal duct probing.

Visual field loss following vitrectomy for stage 2 and 3 macular holes.

AIM--To describe the phenomenon of peripheral field loss following routine pars plana vitrectomy for stage 2 and 3 full thickness macular hole and to investigate the underlying mechanism. METHODS--Five patients, who reported peripheral field defects after apparently uncomplicated vitrectomy, posterior cortical vitreous peeling, and perfluoropropane (C3F8) gas tamponade, were studied retrospectively with slit-lamp biomicroscopy, automated and kinetic perimetry, fundal fluorescein angiography, focal electroretinography (ERG), and colour contrast sensitivity (CCS) testing. RESULTS--All five patients, who were between 50 and 73 years of age, reported an inferotemporal field defect following resolution of the intraocular gas bubble. In all eyes, the scotomata encroached to within 20 degrees to 30 degrees of fixation and to within 5 degrees to 15 degrees of the blind spot. In one eye, a partial altitudinal component was evident. All scotomata subsequently remained stable and three eyes developed subtle segmental nasal disc pallor and nerve fibre loss corresponding to the field defect. CCS testing revealed absent colour contrast in the scotomatous area, in the presence of a preserved focal quadrantic flash ERG, compared with normal CCS protan thresholds and focal ERGs in unaffected quadrants, indicating preserved outer retinal function in the area of the scotoma. CONCLUSIONS--These observations support the hypothesis that field defects occur as a result of retinal nerve fibre layer damage. It is proposed, on the basis of intraoperative observations and other evidence, that the most likely site of nerve fibre damage is at the nasal portion of the optic nerve rim or peripapillary retina, probably due to traction during cortical vitreous peeling.

Incidence of idiopathic full-thickness macular holes in fellow eyes: A 5-year prospective natural history study

PURPOSE This study aimed to determine the incidence of idiopathic full-thickness macular hole (FTMH) in normal fellow eyes and to evaluate the role of electrodiagnostic and psychophysical tests in identifying eyes at risk. PATIENTS AND METHODS A prospective longitudinal natural history study of a cohort of patients with unilateral holes and normal, asymptomatic fellow eyes without posterior vitreous detachment was conducted. Subjects underwent baseline examination, pattern reversal electroretinography, electro-oculography (EOG), and color contrast sensitivity (CCS) testing for protan, deutan, and tritan thresholds and were recalled for clinical examination at 18 months and 5 years. RESULTS At baseline, 114 patients were examined. Eighty were available for review at 18 months, of whom 6 had full-thickness macular holes develop in the fellow eye. At 5 years, 67 of the remaining 74 patients who had not developed holes at 18 months were re-examined and a further 5 were found to have holes develop in the fellow eye. A posterior vitreous detachment without hole formation had developed in 20 fellow eyes at 5 years. Although mean pattern reversal electroretinography and EOG responses were within normal limits in affected and fellow eyes at baseline, mean CCS protan, deutan, and tritan thresholds were elevated significantly in affected eyes at baseline (P = 0.0001). Unaffected fellow eyes showed normal mean protan and deutan thresholds, but significantly elevated mean tritan thresholds (P = 0.01) at baseline. Mean tritan CCS loss was, however, similar in fellow eyes in which holes later developed and in fellow eyes in which holes did not. CONCLUSIONS The Kaplan-Meier estimated risk of fellow eye involvement is 15.6% (range, 8.4%-22.3%; P = 0.05) at 5 years. Although electrodiagnostic and psychophysical testing was not predictive of fellow eye involvement, tritan CCS loss at baseline, in apparently normal fellow eyes, may indicate subclinical foveal dysfunction, the nature of which is unclear.

Ultrasonic assessment of rhinostomy size following external dacryocystorhinostomy

AIM To assess the dimensions and patency of the surgical epithelial fistula after external dacryocystorhinostomy, using B mode ultrasonography to define the postoperative soft tissue anastomosis. METHODS 12 patients undergoing 16 external dacryocystorhinostomies, with the creation of large osteotomies, were included in a prospective study. The horizontal and vertical dimensions of the bone ostium was recorded during surgery and compared with the ultrasonographic dimensions of the soft tissue anastomosis at 1 day, 2 weeks, and 6 months after surgery. Functional patency was confirmed with dye testing and irrigation. RESULTS Compared with an osteotomy of between 100 and 380 mm2 (mean 235 mm2), the soft tissue anastomosis on the day after surgery was, in all cases, markedly smaller (72–252 mm2; mean 144 mm2, or 61% of the bone window). The soft tissue anastomosis decreased to between 8 and 208 mm2 (mean 98 mm2; 68% of immediate postoperative value) at 2 weeks and 3–208 mm2 (mean 71 mm2; 49% of immediate postoperative value) at 6 months. 14 of the 16 (88%) dacryocystorhinostomies were functional at the end of the study, the two failures being associated with marked contracture of the soft tissue anastomosis; the outcome of surgery correlated significantly with the area of the anastomosis at 2 weeks (χ2 = 16.3; p<0.01) and at 6 months (χ2= 16.0, p= 0.01). CONCLUSIONS B mode ultrasonography provides a simple and effective method for assessing the size of the soft tissue anastomosis after external dacryocystorhinostomy and there is a significant reduction in size after surgery, to which the functional outcome of surgery appears related. As the initial soft tissue anastomosis cannot be larger than (and is, on average, about 60% of) the area of the osteotomy, this emphasises the paramount importance of a large rhinostomy to the success of lacrimal surgery.

Idiopathic full thickness macular hole: natural history and pathogenesis

Although full thickness macular holes (FTMH) were originally described in the last century, in relation to trauma,inflammation, and myopia, more recent clinical studies have shown that the vast majority are idiopathic and occur with a prevalence of 1/3300 usually in the 6th and 7th decades of life. Many clinical studies have implicated vitreous traction as the cause of idiopathic FTMH formation and it is now widely accepted that traction at the level of the vitreofoveal interface is the underlying mechanism. Recent work by Kelly and Wendel and others has shown that surgical intervention in the form of vitrectomy, cortical vitreous peeling, and gas tamponade is beneficial in the majority of eyes with FTMH in promoting anatomical closure and foveal reapposition with subsequent visual improvement. In addition, these studies have proposed rigorous face down posturing in the postoperative period as an important factor in achieving improved anatomical results. In the light of the implications of surgical intervention and prolonged face down posturing for elderly patients, the natural history of FTMH has assumed great importance, in particular with respect to fellow eye involvement. The purpose of this review is to summarise the natural history, clinical staging, and pathogenesis of idiopathic FTMH. A number of studies in the 1970s and 1980s attempted to define the clinical characteristics and progression of macular holes. These were difficult to interpret owing to lack of consistency in the definitions used by investigators. In particular, studies investigating the nature of the “prehole” lesion proved controversial. Morgan and Schatz suggested that involutional thinning resulted in a depressed central area at the fovea which represented the prehole lesion, while others proposed that a foveal cyst occurred before hole formation. Several underlying mechanisms were implicated by these investigators, including degenerative macular thinning, degeneration of a macular cyst, intrinsic retinal pigment epithelium …

Visual and anatomical results of surgery for long standing macular holes

AIMS To determine the visual and anatomical outcome of surgery for long standing idiopathic macular holes. METHODS A retrospective review of 24 eyes of all 22 patients who underwent surgery for idiopathic full thickness macular holes (FTMH) symptomatic for between 1 and 3 years. Postoperative follow up was for 6 months. Preoperative and postoperative visual acuities were recorded as well as the presence of anatomical closure of the hole. RESULTS The mean duration of symptoms was 18.21 (SD 5.42) months). Anatomical closure of the FTMH was achieved in 17 (70.8%) of the eyes at 6 months. The logMAR acuity of the group where closure was achieved improved by a mean of 0.31, equivalent to a change of Snellen acuity from 6/60 to 6/29. Where the hole remained open the acuity deteriorated by a mean logMAR of 0.11 lines, equivalent to a change of Snellen acuity from 6/60 to 5/60. Anatomical closure of the hole was associated with a significantly improved acuity over non-closure (p<0.001). The degree of visual improvement was independent of the preoperative visual acuity (Spearman correlation coefficient 0.03, p=0.888), though preoperative acuity was related to the final acuity (Spearman correlation coefficient 0.701, p<0.001). Over the study period, six patients required cataract surgery, one patient developed secondary glaucoma, and one a retinal detachment. CONCLUSIONS Vitrectomy with intraocular gas tamponade and postoperative posturing is a well tolerated and effective intervention for long standing macular holes. Anatomical closure of the macular hole is associated with a significant improvement in visual acuity.

The success and survival of repeat corneal grafts.

The results of 99 second grafts in individual eyes are reported. The five-year survival of these grafts was 49%. Allograft rejection was responsible for the majority of failures, but recurrence of host disease and endothelial decompensation were also important. Glaucoma was an important complication in 38% of eyes. Only 12 eyes in the series had no significant complication and 18 eyes achieved a corrected visual acuity of 6/12 or better.

Pilot randomised controlled trial of face-down positioning following macular hole surgery

ObjectiveThis was a pilot randomised controlled trial (RCT) to investigate the effect of post-operative face-down positioning on the outcome of macular hole surgery and to inform the design of a larger definitive study.MethodsIn all, 30 phakic eyes of 30 subjects with idiopathic full-thickness macular holes underwent vitrectomy with dye-assisted peeling of the ILM and 14% perfluoropropane gas. Subjects were randomly allocated to posture face down for 10 days (posturing group) or to avoid a face-up position only (non-posturing group). The primary outcome was anatomical hole closure.ResultsMacular holes closed in 14 of 15 eyes (93.3%; 95% confidence interval (CI) 68–100%) in the posturing group and in 9 of 15 (60%; 95% CI 32–84%) in the non-posturing group. In a subgroup analysis of outcome according to macular hole size, all holes smaller than 400 μm closed regardless of posturing (100%). In contrast, holes larger than 400 μm closed in 10 of 11 eyes (91%; 95% CI 58–99%) in the posturing group and in only 4 of 10 eyes (40%; 95% CI 12–74%) in the non-posturing group (Fishers exact test P=0.02).ConclusionPost-operative face-down positioning may improve the likelihood of macular hole closure, particularly for holes larger than 400 μm. These results support the case for a RCT.

Vitreoretinal surgery after childhood ocular trauma

AimIn adults modern vitreoretinal surgery allows many traumatised eyes to be salvaged. However, one third of serious eye injuries occur in the paediatric age group and trauma is a leading cause of monocular blindness in childhood. This study aims to report the indications, complications and outcomes for vitreoretinal surgical intervention after childhood ocular trauma.MethodsRetrospective case note review of 61 children (age 16 years or less) undergoing vitreoretinal surgical procedures following ocular trauma at a tertiary referral centre.ResultsTwenty-eight children (45.9%) had open globe injuries (OGI) and 33 closed globe injuries (CGI, 54.1%). The mean age of children with OGI was 9.5 years and with CGI 12.3 years (P=0.0068). Forty-seven children had traumatic retinal detachments (77.1%), which in 17 cases were treated with conventional scleral buckling surgery and in 30 by vitrectomy. Retinal re-attachment was achieved after one procedure in 70.6% with scleral buckling and 46.7% with vitrectomy. Fourteen children (22.9%) had attached retinas but required vitrectomy for other reasons. After a mean follow-up of 19.6 months, the median visual acuity (VA) of the children improved from counting fingers at presentation to 6/36 at final review (P=0.0031). Traumatic retinal detachment requiring vitrectomy was associated with poor visual outcome (P=0.0003).ConclusionVitreoretinal intervention resulted in an improvement in vision in 32 children (57.1%) and stabilised 11 at their presenting acuity (19.6%). Two thirds of the children attained a final VA of 6/60 or better. Proliferative vitreoretinopathy was the cause of redetachment in 68.2% of cases and was significantly associated with a poor outcome (P<0.0001).

Using spectral-domain optical coherence tomography imaging to identify the presence of retinal silicone oil emulsification after silicone oil tamponade.

Purpose: To describe small hyperreflective areas using spectral-domain optical coherence tomography (SD-OCT) imaging in eyes that have had silicone oil tamponade. Methods: Retrospective case series of 11 eyes of 11 patients. The authors retrospectively identified patients who underwent vitrectomy and silicone oil tamponade secondary to a rhegmatogenous retinal detachment (nine patients), panuveitis with retinal necrosis (one patient), or recurrent full-thickness macular hole surgery (one patient) who had manifestations of silicone oil emulsion on SD-OCT imaging. Patients were monitored during the postoperative period by clinical examination and using SD-OCT. A model eye in which emulsified silicone oil had been injected in the anterior chamber was used to obtain anterior segment SD-OCT images for comparison. Results: The mean age of our patients was 50 years (range, 39–76 years). In eight eyes, the SD-OCT examination was carried out after silicone oil removal, and in three eyes, the SD-OCT examination was carried out with the oil in situ. Of the nine eyes treated for rhegmatogenous retinal detachment, five had a relieving retinectomy for advanced anterior proliferative vitreoretinopathy or for traumatic retinal incarceration (one eye). The eye treated for full-thickness macular hole had a vitrectomy, internal limiting membrane peel, and silicone oil injection for recurrent macular hole. Ten eyes showed hyperreflective, spherical, tiny droplets using SD-OCT imaging. These were thought to represent silicone oil droplets intraretinally or underneath epiretinal membranes, and one eye showed hyperreflective areas subretinally (retina detached). One additional patient was found to have tiny intravitreal silicone oil droplets after silicone oil removal. Similarly, the silicone oil appeared as multiple hyperreflective spherical droplets as detected by SD-OCT. Anterior segment studies of silicone oil emulsification in the experimental model revealed a similar appearance to that seen with in vivo SD-OCT imaging. Conclusion: The authors have found small hyperreflective areas intraretinally, subretinally, and underneath epiretinal membranes on SD-OCT in eyes that have had silicone oil tamponade for a variety of indications. The authors have seen a similar appearance when silicone oil emulsification is examined in vivo. The authors conclude that the hyperreflective areas are likely (but not certain) to be very small bubbles of emulsified silicone. Further studies are required to determine the incidence, clinicopathologic, and functional significance of probable silicone oil emulsification and deposition within the retinal layers.