Prescription of near addition and its relation to accommodative reserve in presbyopia - The dichotomy between theory and practice.

PURPOSE: To study the relationship between the amplitude of accommodation (AA) measured by the Royal Air Force (RAF) rule and near addition (NA) prescribed in presbyopic patients to assess how far practice is different from theoretical recommendations. METHODS: Patients, aged 40 to 60 years with best corrected vision of 6/6 N5 were included in this cross sectional observational study. AA was measured using the RAF rule. Refined with near Duochrome chart, the NA was given with the chart at 40 cm. Accommodative reserve was calculated from the measured AA, NA required and the calculated additional accommodation expended by the patient for reading. The percentage of reserve was calculated with and without the correction for depth-of-field. RESULTS: A total of 130 patients were studied. In the patients above 50 years of age, the negative correlation of AA with age was -0.298 (P = 0.065) and AA and NA was -0.365 (P = 0.002) was weak. Among the patients aged between 40 and 50 years, the negative correlation of AA with Age and NA were strong; -0.853 (P < 0.0001) and -0.823 (P < 0.0001) respectively. When prescribing glasses, 62.01% (CI 58.78 to 65.23) and 90.93% (CI 62.50 to 119.37) of the AA was found to be kept in reserve for patients below and above 50 years of age respectively. CONCLUSION: Accommodative reserve kept in our study patients when prescribing NA was two to three times the theoretical recommendation. High percentage of accommodation kept in reserve suggest that the measured AA is not activated normally and require higher NA and one should not rely on patient's ability to generate accommodative power especially in patients over 50 years.

Low vision device requirements among children from two schools for the blind in Tamil Nadu.

PURPOSE: To identify children with low vision from two local schools for the blind, to provide low vision devices (LVD) to those who may benefit from it, and to encourage them to learn print. METHODS: A prospective study was conducted among children from two local schools for the blind. Best-corrected visual acuity (BCVA) was done using the Snellen chart. Children with BCVA of counting finger (CF) 1/2 meter or more in the better eye underwent low vision assessment. Distant vision was assessed using the Feinbloom chart and near vision was assessed using the Lea symbol chart. Low vision devices (LVD) were prescribed as required. RESULTS: Among 185 children enrolled, 31 children had BCVA of >CF ½ meter. Using a telescope, distant vision was better than 3/36 in 48.4%, 3/36-3/12 in 16.2%, and 3/9.5 to 3/3 in 35.4%. Among 23 children who read 1M at <10 cm, 22.6% could read 0.6-0.8M, and 25.8% could read 1M using LVD. CONCLUSION: Regular screening of children in schools for the blind could identify children who might benefit from LVD. A review of protocols for the entry of children in schools for the blind by screening these children by a specialist team prior to admission should be made mandatory.

A reappraisal of indirect choroidal rupture using swept-source optical coherence tomography in-vivo pathology images in patients with blunt eye trauma.

PURPOSE: To describe the in-vivo pathology of indirect choroidal rupture (ICR) in patients with recent ocular trauma using swept-source optical coherence tomography (SSOCT). METHODS: Retrospective observational study of the presenting and follow-up OCT images of four consecutive Asian patients with blunt trauma presenting over a period of 6 months and review of OCT descriptions in the literature. RESULTS: The three patients who presented within 2 weeks of injury showed a gap in the Bruch's membrane (BM)/retinal pigment epithelial complex at the site of the ICR. The distance of the gap ranged from 103 to 465 µm. Blood from associated tear in the choriocapillary layer dissected under the photoreceptor layer to lift it off the retinal pigment epithelium (RPE) layer. The Sattler's and Haller's layers of the choroid were not affected. Fibro-vascular proliferation occurring in the reparative phase bridges the gap in the BM, RPE complex. Late fibrous tissue proliferation extends into the Sattler's layer in the choroid and goes up to the outer nuclear layer in the retina disrupting its architecture. CONCLUSION: SSOCT is a useful tool to study the pathology of recent onset ICR as it is capable of imaging through blood. The primary injury in ICR seems to be a break in the Bruch's membrane. The RPE layer and choriocapillaries get disrupted secondary to the break in the BM as their basement membranes are part of the BM. Scarring during the reparative phase disrupts the adjacent layers of the choroid and retina.

An experimental study to test the efficacy of Mesenchymal Stem Cells in reducing corneal scarring in an ex-vivo organ culture model.

In this study, we evaluated the effect of placenta-derived Mesenchymal Stem Cells (MSCs) versus placebo in improving corneal transparency following experimental injury in an ex-vivo organ culture model of post-mortem human corneas. We also compared the influence of MSCs on the basic histopathology of the cornea and the immunohistochemistry markers of fibrotic corneal scarring. Mesenchymal Stem Cells extracted from the placenta were isolated and expanded in-vitro. Five pairs of post-mortem human corneas harvested for the corneal transplant of equal grade were included in the study. Corneas of the same pair were randomly assigned to either the case arm or the control arm. All corneas underwent a standardized superficial keratectomy, 4 mm in diameter. The case and control arm corneas received an intrastromal injection of MSCs and placebo respectively. The corneal button was maintained in an organ culture system for 28 days under the standard protocol. Laser light was passed through the corneas mounted on a self-styled modified artificial anterior chamber. Image analysis was used to quantify corneal transparency. Haematoxylin & Eosin staining and Immunohistochemistry was done for Alpha SMA (Smooth Muscle Actin). Laser scatter measurements were measured using Image Analysis (Image J Software). The difference in the mean of Full-Width Half Maximum (FWHM), Max intensity and Red pixel intensity between the cases and the controls was 101.5, 16.3 and 11.4 respectively which was found to be statistically significant (P < 0.05). Histopathology showed a disorganized Bowman's layer in the controls as compared to the cases. Alpha Smooth Muscle Actin at the injury site stained 3 + in all controls as compared to 1 + in the cases, showing a statistically significant difference (p = 0.005). Based on our findings, we consider that placenta-derived Mesenchymal Stem Cells can alter evolving corneal scarring into a more favourable outcome with better corneal transparency and lesser fibrotic corneal scarring.

Primary ocular presentation of tuberous sclerosis - A case report.

A 25-year-old man presented with decreased vision in the left eye with hypopigmented elevated subretinal lesion over the optic disk with abnormal vasculature, subretinal and retinal hemorrhages, and fluid in the macula. An area of high spike over the disk with corresponding orbital shadowing was seen on B scan ultrasonography. Fundus fluorescein angiography revealed abnormal vasculature. Systemic examination revealed facial angiofibroma, ashleaf spot, and dental pits with multiple cortical tubers on CT brain. Intravitreal injection of bevacizumab led to visual and tomographic improvement. Abnormal retinal vascularization and exudation in young individuals may be a presenting feature in tuberous sclerosis.

Facilitating factors in overcoming barriers to cataract surgical services among the bilaterally cataract blind in Southern India: A cross-sectional study.

Purpose: To effectively address cataract blindness, increasing sight-restoring surgeries among the bilaterally blind are essential. To improve uptake of surgical services among this group, evidence regarding the problems of access is vital. Barriers in accessing eye care services have previously been reported but not specific to bilaterally cataract blind patients. Further, there is a gap in knowledge regarding factors facilitating access to eye care. Our aims were to (1) report proportion of bilaterally cataract blind patients undergoing surgery and sight restoration rate (SRR) and (2) analyze barriers and factors enabling access to eye care services among bilaterally cataract blind patients. Methods: Retrospective analysis of interview and clinical data of bilaterally cataract blind patients undergoing surgery through outreach services at the base hospital, from June 2015 to May 2016, was performed. Demographic data, vision, postoperative visual outcomes, barriers, and facilitating factors in accessing cataract surgical services were obtained. Results: Bilateral cataract blindness was present in 196/3178 (6.2%, 95% confidence interval 5.4-7.06) patients. SRR was 6.5%. Fear of surgery (24.2%) and lack of family support/escort (22.9%) were the most common barriers. Neighbors and acquaintances (28.6%), general health workers (20.2%), and persons who had undergone cataract surgery (19.6%) were the most common facilitating factors. Conclusion: Proportion of bilaterally cataract blind people undergoing surgery and consequently SRR were low. The most common barriers were at the individual level while facilitating factors at the community level were instrumental in promoting uptake of services. Interventions involving community-based support for the blind may be useful in overcoming barriers to eye care.

Pars-plana fluid aspiration for positive vitreous cavity pressure in anterior segment surgeries.

Positive vitreous pressure due to misdirection of aqueous or choroidal effusion leads to shallowing of the anterior chamber (AC) before or during anterior segment surgeries. This shallow AC if not addressed makes surgery difficult and increases the risk of surgical complications. Methods to prevent and manage this condition described in literature are not without problems. We describe a minimally invasive technique of passing a 30G needle through the pars-plana to aspirate misdirected fluid from vitreous cavity either as a prophylaxis just before surgery or during it, thereby decreasing positive vitreous pressure. This technique, used in 12 eyes, seems to be effective in patients with angle-closure glaucoma, malignant glaucoma, and per-operative sudden increase in vitreous pressure during surgery. Small-incision surgeries are ideally suited for this procedure. This minimally invasive technique is simple to perform and complications are unlikely to be more than what is seen with intravitreal injections.

Successful surgical management of bilateral epiretinal membrane in a child with only café-au-lait spots.

A 6-year-old boy diagnosed as anisometropic amblyopia, with only café-au-lait spots and a family history of neurofibromatosis, presented with decrease in vision in the both eyes. Dilated fundus examination showed epiretinal membrane in both eyes over the macula. He underwent successful surgical management of the epiretinal membrane.

Tenons Patch Graft in the Management of Large Corneal Perforations.

PURPOSE: To describe a technique to manage corneal perforations between 3 and 6 mm in size using autologous Tenons tissue with cyanoacrylate glue and a bandage contact lens. METHODS: A thin layer of Tenons capsule harvested from the patient's own eye is used to seal the perforation and act as a scaffold. The Tenons patch graft is spread over the perforation and held in place by the application of cyanoacrylate glue. A bandage contact lens is then placed on the eye. RESULTS: A 6-year retrospective review of 28 patients who underwent this procedure was performed. One patient was lost to follow-up. Of the 27 patients who were followed up, 20 healed completely, with an adherent leucoma and preservation of the anterior chamber. The condition of one patient (with a perforated Pseudomonas corneal ulcer) progressively worsened despite maximum medical therapy and had to undergo evisceration. CONCLUSIONS: This procedure makes use of easily available autologous Tenons tissue in patients with corneal perforations too large to be managed with cyanoacrylate glue alone, to preserve eyeball morphology. A corneal transplant can then be done when the cornea has healed.

Ocular myiasis in a glioma: a case report.

BACKGROUND: Ocular myiasis though rare, is usually found in association with basal cell carcinoma. It is rarer still in tumors other than basal cell carcinoma. We report a case of ocular myiasis in a glioma which is hitherto unreported to the best of our knowledge. CASE: A 50 year old male presented with bleeding and maggots emanating from a tumourous outgrowth which had replaced his right eye. He complained of swelling and pain in his right eye for the last 2 years. Manual removal of maggots was carried out following which he underwent total excision of the mass and local debridement. Biopsy of the mass was consistent with astrocytoma. CONCLUSION: Myiasis though rare should be suspected in long standing neglected lesions with suggestive history. Infection, ischemic necrosis and malignancy coupled with overcrowding, poor living conditions, presence of excessive arthropods in the locality and low levels of hygiene drastically increase the risk of myiasis.

Unusual presentation of subretinal cysticercosis with hypopyon uveitis.

Subretinal cysticercosis presenting with anterior uveitis and hypopyon is rare. A 7-year-old boy presented with pain and hypopyon in the right eye. Ultrasonography showed a cystic lesion with scolex. Because visual prognosis was poor, he was treated conservatively. Timely diagnosis would facilitate early therapy and prevent visual loss.

Dimensions of the foveal avascular zone using the Heidelberg retinal angiogram-2 in normal eyes.

PURPOSE: The purpose was to study the dimensions of the foveal avascular zone (FAZ) using Heidelberg Retinal Angiogram-2 (HRA-2; Heidelberg Engineering GmBH, Dossenheim, Germany). MATERIALS AND METHODS: An observational study of the FAZ area and circumference was done with fundus fluorescein angiography (FFA) using HRA-2 in 31 normal individuals. The FAZ was studied using both contrast-adjusted and nonadjusted methods. Contrast adjustment was done to obtain better visualization of the finer capillaries around the fovea enabling more precise measurements of the FAZ in normal eyes. RESULTS: The mean area of the FAZ calculated by the contrast-adjusted method was 0.2753 mm 2 (±0.074) and the mean circumference was 2.22 mm (±0.048). By the conventional method, the area and circumference of the FAZ were 0.6241 mm 2 (±0.177) and 3.23 mm (±0.454), respectively. CONCLUSION: The measurements of area and circumference of FAZ using contrast-adjusted methods were significantly smaller than the conventional method.

Correlation between ocular parameters and amplitude of accommodation.

AIM: To study the relationship between ocular parameters and amplitude of accommodation (AA) in the peri-presbyopic age group (35-50 years). MATERIALS AND METHODS: Three hundred and sixteen right eyes of consecutive patients in the age group 35-50 years, who attended our outpatient clinic, were studied. Emmetropes, hypermetropes and myopes with best-corrected visual acuity of 20/20, J1 in both eyes were included. The AA was calculated by measuring the near point of accommodation. The axial length (AL), central anterior chamber depth (CACD) and lens thickness (LT) were also measured. RESULTS: There was moderate correlation (Pearson's correlation coefficient r = 0.56) between AL and AA as well as between CACD and AA (r = 0.53) in myopes in the age group 35-39 years. In the other age groups and the groups taken as a whole, there was no correlation. In hypermetropes and emmetropes, there was no correlation between AA and the above ocular parameters. No significant correlation existed between LT and AA across different age groups and refractive errors. CONCLUSION: There was no significant correlation between AA and ocular parameters like anterior chamber depth, AL and LT.

Orbito-sinal foreign body.

Perforating injuries of the orbit involving the paranasal sinuses are uncommon. We report a case in which a large wooden foreign body lodged in the posterior orbit and maxillary sinus was surgically removed by a combined approach by ophthalmologists and ear, nose and throat surgeons.

Optical coherence tomography in a patient with chloroquine-induced maculopathy.

We herein report the optical coherence tomography (OCT) findings in a case of chloroquine-induced macular toxicity, which to our knowledge, has so far not been reported. A 53-year-old lady on chloroquine for treatment of rheumatoid arthritis developed decrease in vision 36 months after initiation of the treatment. Clinical examination revealed evidence of retinal pigment epithelial (RPE) disturbances. Humphrey field analyzer (HFA), fundus fluorescein angiography (FFA) and OCT for retinal thickness and volume measurements at the parafoveal region were done. The HFA revealed bilateral superior paracentral scotomas, FFA demonstrated RPE loss and OCT revealed anatomical evidence of loss of ganglion cell layers, causing marked thinning of the macula and parafoveal region. Parafoveal retinal thickness and volume measurements may be early evidence of chloroquine toxicity, and OCT measurements as a part of chloroquine toxicity screening may be useful in early detection of chloroquine maculopathy.

Bilateral choroidal metastasis from carcinoma of the submandibular gland.

Metastatic tumor is the most common uveal malignancy. However, choroidal metastasis from a salivary gland neoplasm is extremely rare. We report a case of bilateral, multifocal choroidal metastasis from carcinoma of the submandibular gland.