Safety and efficacy of simultaneous bilateral 25-gauge lens-sparing vitrectomy for vascularly active stage 4 retinopathy of prematurity

Purpose

To report the safety and efficacy of simultaneous bilateral 25-gauge lens-sparing vitrectomy for vascularly active stage 4 retinopathy of prematurity (ROP).

Methods

Retrospective, noncomparative, consecutive case series. Twenty eyes of 10 babies who presented with vascularly active stage 4 ROP in both the eyes underwent simultaneous bilateral 25-gauge lens-sparing vitrectomy. After completing surgery for one eye, the other eye was re-prepped as performed before starting any new case of a different patient and an entire new set of disposable 25-gauge instruments were used. During the post-operative period parents were advised to keep separate eye drops for each eye and to wash their hands in between switching the eyes to put the drops.

Results

The mean follow-up was 8.7 months (range 4–17 months). None of the cases developed any signs of infection. The anatomic success rate for stage 4a was 100% (11/11 eyes) and for stage 4b was 8/9 eyes (89%).

Conclusion

These results show that simultaneous bilateral 25-gauge lens-sparing vitrectomy for stage 4 ROP is a safe and effective procedure with a good outcome provided both eyes of the baby are treated as eyes of two different patients.     

Alternative methods for the screening of retinopathy of prematurity: binocular indirect ophthalmoscopy vs wide-field digital retinal imaging

Purpose

To compare the diagnostic efficacy of wide-field digital retinal imaging (WFDRI) with binocular indirect ophthalmoscopy (BIO) for retinopathy of prematurity (ROP) screening.

Methods

Premature infants admitted for ROP screening were included in this prospective, randomized and double-blind comparative study. They were examined by using BIO and WFDRI.

Results

A total of 58 infants were enrolled in the study. The sensitivities of WFDRI in detecting any stage of ROP, treatment-requiring ROP and plus disease were 58.6, 100, and 100% respectively, with a specificity of 100% for all. The proportional agreement between WFDRI and BIO was 0.903 for detection of any stage of ROP, 1.0 for treatment-requiring ROP, and 1.0 for plus disease.

Conclusion

The sensitivity and specificity of WFDRI was excellent for the diagnosis of severe and treatment-requiring ROP. However, BIO was superior in mild ROP particularly for the ones in retinal periphery.     

The effect of erythropoietin on the severity of retinopathy of prematurity

Aims

Exogenous human erythropoietin (EPO) artificially synthesised through recombinant DNA technology (rHuEPO) is currently used as a substitute for blood transfusion in preterm and low birth weight neonates. The objective of this study is to determine whether the use of rHuEPO is associated with an increased severity of retinopathy of prematurity (ROP) in preterm neonates.

Method

This retrospective review studies neonates who were admitted to a tertiary perinatal unit and screened for ROP during the 10-year period from January 2003 to December 2012.

Results

During the 10-year period, 688 preterm neonates underwent ROP screening, with 198 identified as having ROP. The incidence of stage 1 ROP was 51.5% (102/198), followed by 35.9% (71/198) for stage 2, and 12.6% (25/198) for stage 3 and greater. Plus disease was seen in 14 neonates (7.1%). Treatment (laser photocoagulation) was administered in 64% of neonates (16/25) with stage 3 of the disease and above because of progression to threshold ROP. Twenty-six (13%) of the neonates received rHuEPO treatment. There were no statistically significant differences in birth weight (910.4 vs 885 g; P=0.71), gestational age (26.5 vs 25.8 weeks; P=0.09), and duration of ventilation (512 vs 501.4 h; P=0.92) between neonates who did not receive rHuEPO compared with those who were treated with rHuEPO. Multivariate regression analysis showed that the use of EPO was associated with increased severity of ROP.

Conclusions

EPO therapy appears to increase the risk of development and worsening of ROP.     

Validation of the existing modified screening criteria for detection of all cases of Retinopathy of Prematurity in preterm babies – 11 year study from a governorate referral hospital in Oman

Purpose

To study appropriateness of our modified screening criteria for detection of all cases of Retinopathy of Prematurity (ROP) among preterm babies.

Method

Retrospective observational cohort study among preterm neonates who underwent ROP screening as per set protocol for 11 years at Nizwa Hospital, Al Dhakilya Governorate, Oman. We screened all babies with gestational age ⩽32 weeks or BW ⩽ 1500 g. Preterm babies >32 weeks of GA or BW > 1500 g with unstable clinical course believed to be at high risk by the attending neonatologist also were screened.

Results

During the study period 528 babies were screened for ROP of which 76 babies were excluded due to death, associated congenital ocular malformation and loss for follow-up either due to transfer to other institution or defaulting. Thus 452 babies were included in the final analysis. Incidence of ROP was 46.4% of which 27.9% had mild ROP, 11.3% had severe ROP which regressed and 7.3% had severe ROP who were treated. The incidence of ROP among infants with GA < 26 wks, 26–28 wks, 29–30 wks, 31–32 wks and above 32 weeks was 100.0%, 80.0%, 59.3%, 34.4% and 19.4% respectively.56 babies of this cohort belonged to Extended (modified) criteria group. Among these 12 babies had ROP out of which 9 had mild ROP and 3 had severe ROP. Among cases with severe ROP, two cases regressed spontaneously and one case needed treatment.Multivariate analysis using stepwise regression model showed statistically significant association of GA and BW to development of ROP.We would have missed few babies with ROP if we had followed other criteria.

Conclusion

Our modified screening criteria seem to be appropriate as no infant with severe ROP was missed during the study period. Incidence of severe ROP among babies in the extended criteria group (5.4%) is low but significant compared to lower gestational age. We plan to formulate a scoring system following all risk factor analysis to enable us to optimize the number of infants screened. Detection of all babies with ROP is important as they need long-term follow-up for the timely detection and management of associated ocular comorbidities.     

Refractive errors after the use of bevacizumab for the treatment of retinopathy of prematurity: 2-year outcomes

Purpose

To evaluate the refractive outcomes in children treated after intravitreal injection of bevacizumab (IVB) for retinopathy of prematurity (ROP).

Methods

A retrospective, bi-centre study of 34 patients (64 eyes) was conducted. The patients were divided into three groups, patients received intravitreal IVB (IVB group), patients received combined IVB and laser treatment (IVB+Laser group), or patients received lens-sparing vitrectomy (IVB+LSV group). Cycloplegic refraction and axial length (AXL) were evaluated at 2 years old.

Results

The prevalences of myopia and high myopia were 47.5 and 10.0% in the IVB group, respectively, which were lower than those in the IVB+Laser (82.4 and 29.4%) and IVB+LSV (all 100%) groups (P=0.001 and P<0.001). The prevalences of emmetropia in the IVB group, IVB+Laser group, and IVB+LSV group were 50, 5.9, and 0% (P=0.001). The AXL were similar among all groups.

Conclusions

At the 2-year follow-up, severe ROP patients treated with IVB alone were more likely to remain emmetropic and had lower prevalences of myopia and high myopia. The development of high myopia in severe ROP patients could not be explained by AXL changes but may be associated with abnormalities in the anterior segment.     

Outcomes of 957 preterm neonatal fundus examinations in a Guangzhou NICU through 2008 to 2011

AIM: To take fundus examination in the preterm neonates to observe the common diseases and report the outcomes in a neonatal intensive care unit (NICU) in Guangzhou between May 2008 and May 2011. METHODS: Fundus examinations were performed with Retcam Ⅱ in 957 prematures. RESULTS: There were 957 prematures in this study, including 666 males and 291 females, 2 triple births, 152 twins and 803 singletons. During the three years, 86 infants with any stage retinopathy of prematurity (ROP) (9.0%), 123 infants with retinal hemorrhage(12.9%), 10 infants with neonatal fundual jaundice(1.0%) and 3 babies with congenital choroidal coloboma (0.3%) were found. CONCLUSION: Early detection and prompt treatment of ocular disorders in neonates is important to avoid lifelong visual impairment. Examination of the eyes should be performed in the newborn period and at all well-child visits.     

Evaluating digital diabetic retinopathy screening in people aged 90 years and over

Purpose

To evaluate the effectiveness of digital diabetic retinopathy screening in patients aged 90 years and over.

Methods

This is a retrospective analysis of 200 randomly selected patients eligible for diabetic retinopathy screening aged 90 years and over within the Birmingham, Solihull, and Black Country Screening Programme.

Results

One hundred and seventy-nine (90%) patients attended screening at least once. Outcomes: 133 (74%) annual screening after their first screen, of whom 59% had no detectable diabetic retinopathy; 38 (21%) were referred for ophthalmology clinical assessment—36 for nondiabetic retinopathy reasons and two for diabetic maculopathy. Cataract accounted for 50% of all referrals for ophthalmology clinical assessment. Of the 133 patients placed on annual screening, 93 (70%) were screened at least once more. In terms of level of diabetic retinopathy, assessability or other ocular pathologies, 8 improved, 51 remained stable, and 31 deteriorated. Of the latter, 19 patients were referred for ophthalmology clinical assessment; none of these for diabetic retinopathy.

Conclusions

Screening provides opportunistic identification of important nondiabetic retinopathy eye conditions. However, in view of the low identification rate of sight-threatening diabetic retinopathy in patients aged 90 years and over, and the current mission statement of the NHS Diabetic Eye Screening Programme, systematic annual diabetic retinopathy screening may not be justified in this age group of patients, but rather be performed in optometric practice.     

Astigmatism and biometric optic components of diode laser-treated threshold retinopathy of prematurity at 9 years of age

Purpose

To assess the prevalence of astigmatism and its relationship with biometric optic components in preterm school children with diode laser-treated threshold retinopathy of prematurity (ROP).

Methods

A prospective, cross-sectional study in which cycloplegic keratometry, refraction, and ultrasound biometric measurement of optic components were performed on 24 consecutive preterm children with diode laser-treated threshold ROP at the age of 9 years. The study results were compared with data on 1021 age-matched full-term control children from a national survey.

Results

The laser-treated eyes had a mean astigmatism of 3.47 D, with a mean spherical equivalent of −4.49 D. Of the 46 eyes studied, 98% of eyes showed astigmatism ≥0.5 D and 50% had high astigmatism (>3.0 D). Most astigmatic eyes (97.7%) showed with-the-rule astigmatism, with the mean plus cylinder axis at 89.30^o. Further correlation analysis showed the astigmatism in refraction was highly correlated with the corneal astigmatism (r=0.921, P<0.001) and the vertical corneal curvature (r=0.405, P=0.005). There was significantly steeper vertical corneal curvature (P=0.003) and flatter horizontal corneal curvature (P=0.031) in eyes with laser-treated ROP when compared with age-matched full-term controls. The eyes with laser-treated ROP also show significantly thicker lens (3.93 mm) and shallower anterior chamber depth (ACD; 2.92 mm) than full-term controls (P<0.001).

Conclusions

There is significantly higher prevalence and greater magnitude of astigmatism in eyes with laser-treated threshold ROP compared with full-term controls. The steeper vertical corneal curvature component contributes to the increased astigmatism in eyes with laser-treated ROP.     

RetCam image analysis of the optic disc in premature infants

Purpose

To evaluate the correlation between optic disc parameters and birth weight or gestational age in premature infants.

Methods

RetCam fundal images were taken of 97 premature infants who needed screening for retinopathy of prematurity and who had no ischemic brain injury. The images were taken at a postmenstrual age of 36 weeks and analyzed. The optic disc cup to disc ratio, optic disc area, rim area, and cup to disc area ratio were calculated using image analysis. We evaluated the relationship between these optic disc parameters and gestational age or birth weight.

Results

The optic cup to disc ratio was less than 0.15 in 139 eyes (71.6%) and 0.5 or more in six eyes (3.1%). The optic cup disc area ratio was less than 0.05 in 146 eyes (75.3%) and 0.3 or more in four eyes (2.1%). On evaluating the association between optic disc parameters and gestational age or birth weight, optic disc cup to disc ratio, optic disc area, rim area, and cup to disc area ratio did not show significant relationships.

Conclusion

The optic disc parameters of premature infants had no correlation with birth weight and gestational age.     

Horizontal muscle transposition or oblique muscle weakening for the correction of V pattern?

Purpose

To report and to analyze the efficacy of horizontal rectus muscle transposition and inferior oblique muscle weakening in terms of pattern correction for patients with V pattern.

Methods

The review of the medical files identified 55 patients who had esotropia (ET) or exotropia (XT) with V pattern. The primary outcome measure was the amount of V pattern collapse (Δ).

Results

Of the 55 patients (mean age 22.1±9.5 years), 27 (49.1%) were males and 28 (50.9%) were females. The type of deviations was XT in 30 patients (54.5%) and ET in 25 patients (45.5%). Inferior oblique muscle weakening was performed in 43 (78.2%) patients, whereas horizontal muscle transposition was carried out in 12 (21.8%) patients in addition to recession-resection procedures. The amount of pattern was significantly reduced in both groups (P=0.01 for the horizontal offset group and P<0.01 for the oblique muscle weakening group).

Conclusion

Oblique muscle weakening surgery and horizontal muscle offset are effective in the correction of V pattern when the amount of pattern is under 30Δ.     

Involution patterns of retinopathy of prematurity after treatment with intravitreal bevacizumab: implications for follow-up

Purpose

To describe involution patterns following monotherapy with intravitreal bevacizumab injection (IVB) for type 1 retinopathy of prematurity (ROP) in zone I or zone II posterior.

Methods

A retrospective chart review of infants treated with IVB from January 2010–April 2014. Infants with minimum of 82 weeks postmenstrual age at last follow-up were included. Primary outcome was timing of involution of type 1 ROP for the first 12 weeks post treatment. Secondary outcomes were development of any recurrence and structural outcome at last follow-up. Retinal examination records, fundus, and flourescein angiography images were reviewed.

Results

Twenty-eight eyes were included. Average follow-up post treatment was 33.9±9.7 months (range 21.4–61.9). Cumulative frequency of regression of plus disease was seen in 73.3, 86.7, and 100% of eyes by days 3, 5, and 8, respectively. Regression of both stage 3 and plus disease was observed in 29, 82, 88, and 100% by weeks 1, 2, 3, and 4, respectively. Within the first 3 months, 17/28 eyes developed recurrence to stage 1 or 2 after regression. None developed recurrence of plus disease. By the end of 3 months 18% of eyes vascularized into zone III. At a mean of 24±17.3 months, 39% of eyes were not vascularized into zone III as seen on flourescein angiography with scleral indentation.

Conclusion

Our experience suggests regression of plus disease and stage 3 are expected within the first 4 weeks after bevacizumab treatment. Recurrence may occur despite initial regression and requires careful follow-up.     

The surgical approach to the management of anterior uveal melanomas

Purpose

Surgical excision of peripheral iris or ciliary body melanomas can be performed antero-posteriorly (irido-cyclectomy) with mydriasis or postero-anteriorly (cyclo-iridectomy) with miosis. The aim of this study was to evaluate the results of both surgical techniques.

Methods

Patients were enrolled in the study if they underwent irido-cyclectomy or cyclo-iridectomy for iris and/or ciliary body melanoma at the Liverpool Ocular Oncology Centre between 1993 and 2012.

Results

The 24 patients (8 male, 16 female) had a median age of 57 years. The largest median basal tumour diameter and the median tumour thickness were 4.8 and 2.2 mm, respectively. The resection was performed antero-posteriorly in 9 (37%) patients and postero-anteriorly or circumferentially in 15 (63%). Nine tumours contained epithelioid cells. Genetic studies were performed in 10 patients, showing chromosome 3 loss in two. Postoperative complications included hypotony in 9 (37%) patients, cataract in 8 (33%), hyphaema in 8 (33%), cyclodialysis in 1 (4%), wound dehiscence in 1 (4%) and bullous keratopathy in 1 patient (4%). The median follow-up time was 2.4 years. The last known visual acuity was 6/6–6/12 in 20 (91%) patients and 6/18–6/60 in 2 (9%), with 2 (8%) requiring secondary enucleation. Local tumour recurrence developed in 1 patient (4%). Two (8%) patients died of metastatic disease.

Conclusions

Surgical resection of peripheral iris melanomas achieves high rates of visual conservation and local tumour control and may be the preferred option when tissue is required for laboratory studies.     

A 10-year review of orbital biopsy: the Newcastle Eye Centre Study

Purpose

To review the histopathological diagnoses, visual outcome, and complication rate of orbital biopsy in a UK tertiary referral centre.

Methods

This was a retrospective, clinical–pathological, interventional, consecutive case series. All orbital biopsies performed between July 2004 and June 2014 in Newcastle Eye Centre (Newcastle upon Tyne, UK) were included in this study. All relevant data collected from the local electronic database and medical records were analysed.

Results

A total of 166 orbital biopsies were identified during the study period: 86 patients (53.1%) were female and the mean age was 53.7±19.7 years. Of all the cases, orbital biopsies were performed unilaterally in 158 (97.5%) patients and bilaterally in 4 (2.5%) patients. The mean follow-up period was 2.2±2.3 years. The two most common histopathological diagnoses were non-specific inflammatory disease (62, 38.3%) and lymphoproliferative disease (40, 24.7%). None of the patients experienced ≥2-Snellen line visual loss. There were 7 (4.2%) postoperative complications noted: 1 (0.6%) orbital haemorrhage with no loss of vision, 4 (2.4%) diplopia, 1 (0.6%) short-term symblepharon, and 1 (0.6%) conjunctival granuloma. Postoperative diplopia was associated with lateral orbitotomy (P=0.044) and excisional biopsy (P=0.015).

Conclusions

Orbital biopsy serves as a safe diagnostic tool in managing orbital diseases. Patient should be made aware of the risk of postoperative diplopia. Our data provides useful guidance to clinicians when counselling patients for orbital biopsy.     

Determination of visual prognosis in children with open globe injuries

Aims

To determine the predictive factors of visual outcomes in children with open globe injury and to give guidance to reduce the incidence of open globe injury.

Methods

One hundred and forty eyes of 137 consecutive open globe injury patients, who were treated at the Eye Center of Second Bethune Hospital affiliated with Jilin University between August 2005 and August 2012, were retrospectively analyzed. Data recorded included demographic characteristics, causes of injury, location and extent of injury, presenting visual acuity, detailed ocular anterior and posterior segment evaluations, details of primary and subsequent surgeries, and postoperative complications and outcomes. The follow-up data included the most recent best-corrected visual acuity, complications, and the duration of follow-up.

Results

Of the 137 patients, there were 116 (84.7%) boys and 21 (15.3%) girls. Their ages ranged between 3 and 17 years old (mean=11.57±4.19 years old). Sixty (43.8%) children had a right eye injury, whereas 74 (54.0%) had a left eye injury. Only three (2.2%) children suffered bilateral eye injury. Living utensils, industrial tools, and fireworks contributed to the most common causes of open globe injury. Eighty-one (59.1%) had sharp force injuries, 23 (16.8%) had blunt injuries, and 33 (24.1%) had missile injuries.

Conclusions

Unfavorable visual outcomes were related to a younger age at presentation, poor presenting visual acuity, injuries caused by blunt or missile objects, posterior wound location, hyphema, vitreous hemorrhage, and surgical intervention of pars plana vitrectomy.     

Incidence and indications for pars plana vitrectomy following the treatment of posterior uveal melanomas in Scotland

Background

Globe-sparing treatments such as plaque brachytherapy, local or endoresection, and proton beam therapy (PBT) are the treatments of choice for posterior uveal melanoma. However, both early and late complications can arise from these techniques, including vitreous haemorrhage (VH) and retinal detachment (RD). Choroidal melanomas in Scotland are managed by a single unit, the Scottish Ocular Oncology Service (SOOS).

Methods

Indications and outcomes from surgery were analysed for patients undergoing vitrectomy following treatment for uveal melanoma in the SOOS between 1998 and 2013.

Results

Seventeen from 715 cases (2.4%) required vitrectomy, of which 8/445 (1.8%) followed plaque brachytherapy, 7/43 (16.3%) combined local resection and brachytherapy, and 2/227 (0.9%) PBT. Casenotes were reviewed for 16/17 cases, with surgery indicated for VH in 10 (63%), RD in 5 (31%), and combined VH/RD in 1 (6%). The median interval from initial tumour treatment to vitrectomy was 5.8 months (range 10 days to 8.8 years). Ten (63%) required early vitrectomy (within 6 months), of which the majority (70%) followed combined resection/brachytherapy. Six (37%) required late vitrectomy (after 6 months), of which all were non-clearing VH following plaque brachytherapy, with proliferative retinopathy in 4/6 (67%), and tumour recurrence in 2/6 (33%). Overall vision improved in 8 eyes (50%), remained the same in 2 (12.5%), and deteriorated in 6 (37.5%).

Conclusions

Early vitrectomy was most commonly indicated for RD following local resection, and late vitrectomy for VH due to radiation retinopathy. The majority of patients undergoing vitrectomy gained or maintained vision.     

Relationship between paravascular abnormalities and foveoschisis in highly myopic patients

Purpose

To describe the prevalence of paravascular abnormalities in highly myopic patients and its relationship with myopic foveoschisis (MF).

Methods

Cross-sectional study of 250 highly myopic eyes. All of the patients underwent a complete ophthalmologic examination that included optical coherence tomography .

Results

Optical coherence tomography images showed 170 eyes (68%) with paravascular microfolds (PM), 121 eyes (48.4%) presented paravascular retinal cysts (PC), and 35 eyes (14%) with paravascular lamellar holes . All the eyes with PCs had PMs. Out of the 250 eyes, 48 (19.2%) had paravascular retinoschisis (PR). All the eyes (100%) with PR had paravascular cysts and PMs. Sixteen eyes (6.4%) had foveoschis. The spherical equivalent (P<0.00), PR (P=0.01), and the presence of tractional structures (P<0.00) were associated with increased risk for foveoschsis in the multivariate study.

Conclusions

PMs were the lesions most often observed in the paravascular area in highly myopic eyes. MF would be a result of the action of different forces (intra- and extra-ocular forces), specially tractional structures, on precursor lesions (paravascular cyst and paravascular restinoschisis). Further studies are needed to confirm these results.     

Incidence of deepening of the upper eyelid sulcus in prostaglandin-associated periorbitopathy with a latanoprost ophthalmic solution

Purpose

Among some local side effects of prostaglandin-associated periorbitopathy (PAP), deepening of the upper eyelid sulcus (DUES) is the most prominent clinical feature, and is one of the most significant adverse cosmetic events. Here, we prospectively investigated the incidence of DUES in Japanese open-angle glaucoma patients initially treated with latanoprost (Xalatan 0.005%) ophthalmic solution.

Methods

This was an open-label prospective study. Facial photographs and subjective reports of the recognition of DUES were obtained at the beginning of latanoprost treatment and at 2, 4, and 6 months thereafter. Intraocular pressure (IOP) was measured at three consecutive visits before and after treatment with latanoprost. The incidence of DUES was evaluated objectively by three blinded investigators who compared the series of photographs.

Results

A total of 52 eyes of 52 newly diagnosed open-angle glaucoma Japanese patients (28 males, 24 females) were evaluated. The objective rate of DUES was 1/52 (2% 95% CI 0.05 to 10.7%) at 2 months, 2/52 (4% 95% CI 0.5 to 13.9%) at 4 months, and 3/52 (6% 95% CI 1.2 to 16.9%) at 6 months. During this period, no patient self-reported an occurrence of DUES. Mean IOPs before and after treatment were 16.5±2.9 and 13.8±3.0 mm Hg, respectively. Latanoprost reduced the IOP significantly (P<0.0001, paired t-test).

Conclusions

Latanoprost caused DUES rarely and had a robust IOP-lowering effect in Japanese glaucoma patients.     

Acute corneal hydrops in keratoconus: a national prospective study of incidence and management

Purpose

To determine incidence and management of acute corneal hydrops in the UK.

Methods

We used the BOSU report card system to survey cases of acute corneal hydrops in patients with keratoconus that occurred in the UK between November 2009 and December 2010. Ophthalmologists who reported a case were sent an initial questionnaire, with a follow-up questionnaire after 6 months. We collected information on the demographics, complications, changes in visual acuity, and management. The 2011 National Census was used as a source for population and ethnicity in the UK.

Results

There were 73 incident cases of acute corneal hydrops, with a response to the initial questionnaire for 64 (88%) patients and follow-up data at 6 months for 57 (78%) patients. For the 64 confirmed cases the median (interquartile range) age of onset was 31.9 (23.2, 41.3) years and 48 (75%) of the cases occurred in males. A total of 42 (66%) patients were white, 14 (22%) were South Asian, and 7 (11%) were black. The proportion of South Asian and black patients with acute corneal hydrops was significantly higher than in the general population (P<0.001). The minimum estimated annual incidence of acute corneal hydrops in patients with keratoconus was estimated to be 1.43 (1.10, 1.83) per 1000. At 6 months following acute corneal hydrops a decision to proceed with keratoplasty had been made for 12 (20.3%) patients.

Conclusions

This is the first population-based estimate of the incidence of acute corneal hydrops in keratoconus.     

Retinal video recordings at different compression levels: a novel video-based imaging technology for diabetic retinopathy screening

Background

To evaluate the optimal compression level of retinal color digital video recordings, a novel video-based imaging technology, in screening for diabetic retinopathy (DR).

Design

Evaluation of a diagnostic technique.

Methods

A total of 36 retinal videos, captured using EyeScan (Ophthalmic Imaging System), were compressed from original uncompressed file size of 1 GB (gigabyte) to four different compression levels—100 MB (megabyte) (Group 1); 30 MB (Group 2); 20 MB (Group 3); and 5 MB (Group 4). The videos were subsequently interpreted by an ophthalmologist and a resident using the International Clinical Diabetic Retinopathy Severity Scales.

Main outcome measures

The sensitivity, specificity and κ coefficient for DR grading detected by were calculated for each compression level (Groups 1–4), with reference to the original uncompressed retinal videos.

Results

Groups 1, 2, and 3 graded by both readers had sensitivity and specificity >90% in detecting DR, whereas for group 4, the sensitivity and specificity were 70.6% and 94.7% for ophthalmologist and 80.0% and 72.2% medical officer, respectively. The κ correlation in detecting DR for groups 1, 2, and 3 were >0.95, whereas for Group 4, the κ was 0.76 and 0.66 for ophthalmologist and medical officer, respectively.

Conclusion

Retinal video recording is a novel and effective DR screening technique with high sensitivity, specificity and κ correlation. With its compressibility, this is a potential effective technique that can be widely implemented in a routine, mobile, and tele-ophthalmology setting for DR screening services.     

The noninvasive retro-mode imaging of confocal scanning laser ophthalmoscopy in myopic maculopathy: a prospective observational study

Purpose

To investigate the morphological features of myopic maculopathy with a new and noninvasive retro-mode imaging (RMI) technique using a confocal scanning laser ophthalmoscope.

Methods

A total of 42 patients (69 eyes) with myopic maculopathy were included. RMI combined with fundus photography, fundus fluorescein angiography, and optical coherence tomography together were used to observe and evaluate the morphological features of disease.

Results

Four in 4 eyes (100%) with macular retinoschisis were found with a characteristic pattern by RMI (firework pattern centrally with surrounding fingerprint pattern). Twenty-four in 24 eyes (100%) with pigment proliferation were found by RMI as dark plain patches, and 23 in 24 eyes with hemorrhage (95.8%) were found by RMI as gray bump. Atrophy of different degrees (12 in 14 eyes, 85.7%) was found by RMI as an area of pseudo-3D choroidal vessels or a fuzzy shadow but both without a clear boundary. Choroidal neovascularization (12 in 16 eyes, 75%) was identified laboriously by RMI as a vague raised region. Lacquer cracks were difficult to figure out in RMI.

Conclusions

Retinoschisis, pigment proliferation, hemorrhage, and atrophy secondary to myopic maculopathy have characteristic morphologic features in RMI; however, choroidal neovascularization and lacquer crack are not easily distinguishable in RMI.