Endoscopic Endonasal Transsphenoidal Resection of Pituitary Adenomas in Patients Presenting With Monocular Blindness

BACKGROUND AND OBJECTIVES

Suprasellar tumors, particularly pituitary adenomas (PAs), commonly present with visual decline, and the endoscopic endonasal transsphenoidal approach (EETA) is the primary management for optic apparatus decompression. Patients presenting with complete preoperative monocular blindness comprise a high-risk subgroup, given concern for complete blindness. This retrospective cohort study evaluates outcomes after EETA for patients with PA presenting with monocular blindness.

METHODS

Retrospective analysis of all EETA cases at our institution from June 2012 to August 2023 was performed. Inclusion criteria included adults with confirmed PA and complete monocular blindness, defined as no light perception, and a relative afferent pupillary defect secondary to tumor mass effect.

RESULTS

Our cohort includes 15 patients (9 males, 6 females), comprising 2.4% of the overall PA cohort screened. The mean tumor diameter was 3.8 cm, with 6 being giant PAs (>4 cm). The mean duration of preoperative monocular blindness was 568 days. Additional symptoms included contralateral visual field defects (n = 11) and headaches (n = 10). Two patients presented with subacute PA apoplexy. Gross total resection was achieved in 46% of patients, reflecting tumor size and invasiveness. Postoperatively, 2 patients experienced improvement in their effectively blind eye and 2 had improved visual fields of the contralateral eye. Those with improvements were operated within 10 days of presentation, and no patients experienced worsened vision.

CONCLUSION

This is the first series of EETA outcomes in patients with higher-risk PA with monocular blindness on presentation. In these extensive lesions, vision remained stable for most without further decline and improvement from monocular blindness was observed in a small subset of patients with no light perception and relative afferent pupillary defect. Timing from vision loss to surgical intervention seemed to be associated with improvement. From a surgical perspective, caution is warranted to protect remaining vision and we conclude that EETA is safe in the management of these patients.

Recovery of Vision in Open Globe Injury Patients with Initial No Light Perception Vision

PURPOSE

To identify clinical characteristics of injured eyes associated with visual recovery in patients with open globe injuries (OGIs) and presenting with no light perception (NLP) vision.

DESIGN

Retrospective chart review.

SUBJECTS

All patients presenting to Massachusetts Eye and Ear with OGI and NLP vision from January 1999 to March 2022.

METHODS

Manual data extraction to collect patient demographic characteristics, preoperative, intraoperative, and postoperative characteristics of OGI injury, laceration versus rupture, history of intraocular surgery, time from injury to repair, timing of vitrectomy, lensectomy, choroidal drainage, and silicone oil placement, visual acuity (VA) at last follow-up, and subsequent B-scan ultrasound findings of retinal detachment, choroidal hemorrhage, vitreous hemorrhage, and disorganized intraocular contents. Patients with >1 week of follow-up and a documented VA at most recent follow-up were included. Exclusion criteria included age <10 years. Multivariable regression was performed.

MAIN OUTCOME MEASURES

Visual acuity recovery defined as light perception or better in patients with OGI and initial NLP vision.

RESULTS

One hundred forty-seven eyes with NLP vision after OGI were included. Twenty-five (17%) eyes regained vision at last follow-up. The majority of patients recovered light perception vision (n = 15, 60%) followed by 20/500 or better (n = 5, 20%), hand motions (n = 3, 12%), and counting fingers (n = 2, 8%). Most injuries were zone III (n = 102, 69%) and presented with rupture (n = 127, 86%). The mean time from OGI to surgical repair was 0.85 ± 1.7 days. B-scan was obtained in 104 (71%) cases. Pars plana vitrectomy was performed in 9 eyes (6%) with NLP at time of vitrectomy. Disorganized intraocular contents on B-scan (odd ratio, 0.170; 95% confidence interval, 0.042-0.681; P = 0.012) was the only clinical variable significantly associated with visual recovery, corresponding to a lack of visual improvement.

CONCLUSIONS

Recovery of vision in OGI with NLP vision at presentation cannot be predicted based on presenting clinical features. B-scan findings of disorganized intraocular contents after initial OGI repair was the only factor negatively associated with vision recovery in this patient population. Therefore, all eyes presenting with an OGI and NLP vision should undergo primary repair in hopes of subsequent visual recovery.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Emergency surgical decompression of the orbit may rescue impaired vision even in a patient presenting late with a retrobulbar haematoma: A case report from rural southwestern Uganda

Retrobulbar haematoma is a rare emergency that can potentially lead to blindness. Common causes include facial trauma and surgery. Timely surgical evacuation of the haematoma improves visual outcomes. In rural communities, patients often present to hospital after many hours and this increases the risk of poor visual outcomes. Radiological evaluation which is often not available in rural communities, results in further delay in surgical treatment. This case report highlights the need for urgent surgical intervention over radiological evaluation in patients with retrobulbar haematoma and orbital compartment syndrome.

Endoscopic endonasal decompression of the optic nerve in the setting of compressive lesions: how I do it

BACKGROUND

Many lesions in the anterior skull base may compress the optic nerve (ON), leading to vision loss, and even irreversible blindness. Although decompression of the optic nerve has traditionally been achieved transcranially, the endoscopic endonasal approach (EEA) is gaining traction as a minimally invasive approach recently.

METHOD

We describe the key steps of an EEA ON decompression. The relevant surgical anatomy with illustration is described. Additionally, a video detailing our technique and instruments on an illustrative case is provided.

CONCLUSION

Endoscopic endonasal approach ON decompression with a straight feather blade is a feasible, minimally invasive procedure to decompress the ON in the setting of anterior skull base mass lesions.

Minimally Invasive Bleb Surgery for Glaucoma: A Health Technology Assessment

Background

Glaucoma is the term for a group of eye disorders that causes progressive damage to the optic nerve, which can lead to visual impairment and, potentially, irreversible blindness. Minimally invasive bleb surgery (MIBS) reduces eye pressure through the implantation of a device that creates a new subconjunctival outflow pathway for eye fluid drainage. MIBS is a less invasive alternative to conventional/incisional glaucoma surgery (e.g., trabeculectomy). We conducted a health technology assessment of MIBS for people with glaucoma, which included an evaluation of effectiveness, safety, the budget impact of publicly funding MIBS, and patient preferences and values.

Methods

We performed a systematic literature search of the clinical evidence. We assessed the risk of bias of each included study using the Cochrane Risk of Bias 1.0 tool for randomized controlled trials (RCTs) and the Risk of Bias Assessment tool for Nonrandomized Studies (RoBANS) for comparative observational studies, and the quality of the body of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. We conducted an economic literature search and we estimated the budget impact of publicly funding MIBS in Ontario. We did not conduct a primary economic evaluation due to the limited long-term effectiveness data. We summarized the preferences and values evidence from previous health technology assessments to understand the perspectives and experiences of patients with glaucoma.

Results

We included 41 studies (2 RCTs and 39 comparative observational studies) in the clinical evidence review. MIBS may reduce intraocular pressure and the number of medications used, but we are uncertain if MIBS results in outcomes similar to trabeculectomy (GRADE: Moderate to Very low). Compared with trabeculectomy, MIBS may result in fewer follow-up visits and interventions, and adverse events (GRADE: Moderate to Very Low). MIBS may also reduce intraocular pressure and the number of antiglaucoma medications used, compared with other glaucoma treatments, but the evidence is uncertain (GRADE: Very low). Our economic evidence review identified two directly applicable studies. The results of these studies indicate that the cost-effectiveness of MIBS is highly uncertain, and the cost of glaucoma interventions are likely to vary across provinces. The annual budget impact of publicly funding MIBS in Ontario ranged from $0.11 million in year 1 to $0.67 million in year 5, for a total 5-year budget impact estimate of $1.93 million. Preferences and values evidence suggests that fear of ultimate blindness and difficulty managing medication for glaucoma led patients to explore other treatment options such as MIBS. Glaucoma patients found minimally invasive glaucoma surgery (MIGS) procedure beneficial, with minimal side effects and recovery time.

Conclusions

Minimally invasive bleb surgery reduces intraocular eye pressure and the number of antiglaucoma medications needed, but we are uncertain if the outcomes are similar to trabeculectomy (GRADE: Moderate to Very low). However, MIBS may be safer than trabeculectomy (GRADE: Moderate to Very low) and result in fewer follow-ups (GRADE: Moderate to Very low). MIBS may also improve glaucoma symptoms compared with other glaucoma treatments, but the evidence is very uncertain (GRADE: Very low).We estimate that publicly funding MIBS would result in an additional cost of $1.93 million over 5 years. Patients who underwent MIGS procedures found them to be generally successful and beneficial, with minimal side effects and recovery time. We could not draw conclusions about specific MIBS procedures or long-term outcomes.

Pediatric Corneal Transplantation in Uyo, Nigeria: Early Experiences

ABSTRACT

The burden of avoidable blindness from corneal disease is significantly higher where access to specialist eye care, the cost of treatment and the treatment infrastructure including eye banking, are beyond the reach of the impoverished masses. Corneal transplantation in children is challenging: it is more technically complex; patients often require multiple examinations under general anaesthesia to optimize treatment outcomes. There is also the increased risk of several complications including graft dehiscence, infection, rejection, and inappropriate patient or caregiver care. However, when successful, it restores vision. We present a report of our initial experience with penetrating keratoplasty in 2 children with blinding corneal disease in Uyo, Nigeria. Corneal transplantation history was retrieved and data (including data on age, sex, aetiology of corneal disease, indications for corneal transplantation, pre-operative and post-operative visual acuity and intraocular pressure measurements) was extracted for this report. Both patients had standard penetrating keratoplasty performed by one surgeon, under general anaesthesia. Case one was a 10-year-old male presenting with profound visual impairment from congenital hereditary endothelial dystrophy. His best corrected post-operative visual acuity was 6/24. Case two was a 3-year-old male with vision loss due to a corneal leucoma following treated herpes simplex keratitis. Post-operatively, his best corrected visual acuity improved to 6/12. Corneal graft tissue remained clear at more than 3 years of follow-up. Although amblyopia was a notable co-morbidity, corneal transplantation significantly improved their vision. Corneal banking services are advocated for in resource-limited settings where the magnitude of corneal blindness is greatest.

Indications and types of keratoplasties: Trends in the past 10 years (2011-2020) in Eastern India

Purpose

To observe the trends of various types of keratoplasties in different etiologies over a period of 10 years (2011-2020) in a tertiary eye care center of eastern India.

Methods

A retrospective review of patients undergoing keratoplasties from 2011 to 2020 was performed in a tertiary eye care hospital situated in eastern part of India. Apart from demographic data, primary indication for each surgery and type of procedure carried out was recorded. For comparison, data were divided into two time periods: Group I: Jan 2011 to Dec 2015 and Group II: Jan 2016 to Dec 2020.

Results

Over a period of 10 years, a total of 2365 (Group I: 902, Group II: 1463) keratoplasties were performed. The average age of patients was 45.8 ± 19.9 and 46.9 ± 20.9 years in Group I and Group II, respectively. Among all the corneal grafts, 1747 (74%) surgeries were full-thickness. Although optical penetrating keratoplasty (OPK) was most the common indication for full-thickness keratoplasties, Descemet's stripping endothelial keratoplasty (DSEK) remained most performed lamellar keratoplasty. Keratitis, corneal scars, and bullous keratopathies remain to be most common indications in both groups. Number of lamellar keratoplasties increased significantly from Group I to Group II for corneal scars (P = 0.02), bullous keratopathies (P = 0.01), and endothelial dystrophies (P = 0.00).

Conclusion

With change in time, the indication and technique of keratoplasty has witnessed a changing trend from full-thickness keratoplasty to lamellar keratoplasty. There is rise in trend of lamellar keratoplasties over the period.

Keratoprosthesis in dry eye disease

Bilateral corneal blindness with severe dry eye disease (DED), total limbal stem cell deficiency with underlying corneal stromal scarring and vascularization, combined with adnexal complications secondary to chronic cicatrizing conjunctivitis is a highly complex situation to treat. In such eyes, procedures such as penetrating keratoplasty alone or combined with limbal stem cell transplantation are doomed to fail. In these eyes, keratoprosthesis (Kpro) or an artificial cornea is the most viable option, eliminating corneal blindness even in eyes with autoimmune disorders such as Stevens-Johnson syndrome, ocular mucous membrane pemphigoid, Sjogren's syndrome, and nonautoimmune disorders such as chemical/thermal ocular burns, all of which are complex pathologies. Performing a Kpro in these eyes also eliminates the need for systemic immunosuppression and may provide relatively early visual recovery. In such eyes, the donor cornea around the central cylinder of the Kpro needs to be covered with a second layer of protection to avoid desiccation and progressive stromal melt of the underlying cornea, which is a common complication in eyes with severe DED. In this review, we will focus on Kpro designs that have been developed to survive in eyes with the hostile environment of severe DED. Their outcomes in such eyes will be discussed.

Postoperative Complications in the Primary Tube Versus Trabeculectomy Study During 5 Years of Follow-up

PURPOSE

To describe postoperative complications encountered in the Primary Tube Versus Trabeculectomy (PTVT) Study during 5 years of follow-up.

DESIGN

Multicenter randomized clinical trial.

PARTICIPANTS

A total of 242 eyes of 242 patients with medically uncontrolled glaucoma and no previous incisional ocular surgery, including 125 patients in the tube group and 117 patients in the trabeculectomy group.

METHODS

Patients were enrolled at 16 clinical centers and randomly assigned to treatment with a tube shunt (350-mm2 Baerveldt glaucoma implant) or trabeculectomy with mitomycin C (MMC, 0.4 mg/ml for 2 minutes).

MAIN OUTCOME MEASURES

Surgical complications, reoperations for complications, visual acuity, and cataract progression.

RESULTS

Early postoperative complications occurred in 24 patients (19%) in the tube group and 40 patients (34%) in the trabeculectomy group (P = 0.013). Late postoperative complications developed in 27 patients (22%) in the tube group and 32 patients (27%) in the trabeculectomy group (P = 0.37). Serious complications producing vision loss and/or requiring a reoperation were observed in 3 patients (2%) in the tube group and 9 patients (8%) in the trabeculectomy group (P = 0.11). Cataract progression was seen in 65 patients (52%) in the tube group and 52 patients (44%) in the trabeculectomy group (P = 0.30). Surgical complications were not associated with a higher rate of treatment failure (P = 0.61), vision loss (P = 1.00), or cataract progression (P = 0.77) CONCLUSIONS: A large number of surgical complications were observed in the PTVT Study, but most were transient and self-limited. The incidence of early postoperative complications was higher following trabeculectomy with MMC than with tube shunt surgery. The rates of late postoperative complications, serious complications, and cataract progression were similar with both surgical procedures after 5 years of follow-up. Surgical complications did not increase the risk of treatment failure, vision loss, or cataract progression.

[The research progress of mesenchymal stem cell induction and differentiation into corneal tissue]

Keratopathy is one of the most important blinding eye diseases in the world. Corneal opacity caused by keratopathy can seriously damage visual function. For example, corneal ulcer can lead to perforation and even loss of the eyeball. Although corneal transplantation is a routine treatment in clinical practice, there are not only a serious shortage of corneal donors in our country, but also various complications after keratoplasty that can not be avoided. In recent years, with the rapid development of regenerative medicine, it has been found that mesenchymal stem cells can differentiate into a variety of functional cells including corneal tissue under suitable induction conditions, which has a broad prospect of clinical application. This finding provides new ideas and methods for the treatment of keratopathy and corneal blindness in many aspects. This article reviews the research status of induction methods of mesenchymal stem cells in various specialties, particularly in the corneal subspecialty.

Osteo-odonto-keratoprosthesis according to Strampelli original technique: A retrospective study with up to 30 years of follow-up

PURPOSE

To describe clinical, anatomical, and visual outcomes obtained from a long-term follow-up of 59 patients who underwent osteo-odonto-keratoprosthesis (OOKP) using the original Strampelli technique.

DESIGN

retrospective clinical cohort study.

METHODS

82 eyes of 59 patients who underwent OOKP surgery between 1969 and 2011 were included. Patients' clinical characteristics before surgery as well as complications and further surgeries until the end of follow-up were recorded. BCVA was revised before surgery and at 1 month, 1 year and every 5 years until the 30th year of follow-up.

RESULTS

Mean follow-up post-OOKP was 27.4±11.2 years (2.4-52). The most frequent cause of blindness was chemical injuries (71%). OOKP integrity was maintained in 77 out of 82 eyes until the end of follow-up (94%). Excluding the cataract, acquired glaucoma was the most frequent complication with a prevalence at 10 years of 36%. Mean BCVA improved from 2.60±0.32 at presentation to 0.40±0.65 at 1 year and 1.21±1.19 logMAR at 30 years. Overall, 51% of the included eyes attained a BCVA better than 0.05 logMAR and a stabilization of BCVA was observed for the first 10 years of follow-up post-OOKP. Better BCVA outcomes were observed in the Stevens-Johnson Syndrome or Toxic Epidermal Necrolysis (SJS/TEN) group, while glaucoma showed not to significantly affect visual acuity.

CONCLUSIONS

The original OOKP still represents a valid surgical choice, durable over time, for restoring vision in end-stage corneal blindness patients not eligible for a corneal transplant.

The First Epiretinal Implant for Hereditary Blindness in the Asia-Pacific Region

In February 2013, the Argus® II Retinal Prosthesis System (Second Sight Medical Products, Inc., Sylmar, CA, US) became the first "bionic eye" approved by the FDA to restore useful vision in patients previously blinded by end-stage retinitis pigmentosa, a hereditary, progressive degeneration of the outer retinal photoreceptor cells. The system captures and converts an external optical input into an electrical signal that activates an epiretinal electrode array on the inner surface of the retina. This signal bypasses dysfunctional photoreceptors and directly stimulates the functional inner retina, thus transmitting information to the visual cortex and creating artificial vision. This article describes the first implantation of the Argus II Retinal Prosthesis System in the Asia-Pacific region, which occurred in a deaf and blind 72-year-old Japanese American woman with Usher syndrome. At 57 months after her operation, the patient uses the device daily to perform visual tasks, and the microelectrode array remains in the proper position on the macula. This case demonstrates the long-term safety and efficacy of the Argus II epiretinal implant, which allowed a functionally blind patient to gain meaningful vision.

Learning to perceive shape from temporal integration following late emergence from blindness

Visual perception requires massive use of inference because the 3D structure of the world is not directly provided by the sensory input.¹ Particularly challenging is anorthoscopic vision-when an object moves behind a narrow slit such that only a tiny fraction of it is visible at any instant. Impressively, human observers correctly recognize objects in slit-viewing conditions by early childhood,^2,3 via temporal integration of the contours available in each sliver.^4,5 But can this capability be acquired if one has been effectively blind throughout childhood? We studied 23 Ethiopian children which had bilateral early-onset cataracts-resulting in extremely poor vision in infancy-and surgically treated only years later. We tested their anorthoscopic vision, precisely because it requires a cascade of demanding visual inference processes to perceive veridical shape. Failure to perform the task may allow mapping specific bottlenecks for late visual recovery. The patients' visual acuity typically improved substantially within 6 months post-surgery. Still, at this stage many were unable to recover shape under slit-viewing conditions, although they could infer the direction of global motion. However, when retested later, almost all patients could judge shape in slit-conditions necessitating temporal integration. This acquired capability often transferred to novel stimuli, in similar slit-viewing conditions. Thus, learning was not limited to the specific visual features of the original shapes. These results indicate that plasticity of sophisticated visual inference routines is preserved well into adolescence, and vision restoration after prolonged early-onset blindness is feasible to a greater extent than previously thought.

Keratoprosthesis: Current Choices and Future Development

Keratoprosthesis (KPro) is the last resort for corneal blindness. Boston KPro I and osteo-odonto-keratoprosthesis (OOKP) have the most favorable outcomes for their respective indications. Recently, better outcomes have been achieved for these 2 devices mainly because of improvements in postoperative care and modifications in complication management through years of experience and research. Unfortunately, some patients cannot benefit from these KPros due to lack of access to devices, trained surgeons, or both. Boston KPro I is heading toward a more affordable variation particularly for patients in developing countries. In addition, more patients with severely compromised ocular surface will be candidates for Boston KPro II variants. Biosynthetic or synthetic OOKP analogues will make the operation less complex and suitable for patients without canine tooth.

Cataract Services are Leaving Widows Behind: Examples from National Cross-Sectional Surveys in Nigeria and Sri Lanka

The Sustainable Development Goals aim to leave no one behind. We explored the hypothesis that women without a living spouse—including those who are widowed, divorced, separated, and never married—are a vulnerable group being left behind by cataract services. Using national cross-sectional blindness surveys from Nigeria (2005–2007; n = 13,591) and Sri Lanka (2012–2014; n = 5779) we categorized women and men by marital status (married/not-married) and place of residence (urban/rural) concurrently. For each of the eight subgroups we calculated cataract blindness, cataract surgical coverage (CSC), and effective cataract surgical coverage (eCSC). Not-married women, who were predominantly widows, experienced disproportionate cataract blindness—in Nigeria they were 19% of the population yet represented 56% of those with cataract blindness; in Sri Lanka they were 18% of the population and accounted for 54% of those with cataract blindness. Not-married rural women fared worst in access to services—in Nigeria their CSC of 25.2% (95% confidence interval, CI 17.8–33.8%) was far lower than the best-off subgroup (married urban men, CSC 80.0% 95% CI 56.3–94.3); in Sri Lanka they also lagged behind (CSC 68.5% 95% CI 56.6–78.9 compared to 100% in the best-off subgroup). Service quality was also comparably poor for rural not-married women—eCSC was 8.9% (95% CI 4.5–15.4) in Nigeria and 37.0% (95% CI 26.0–49.1) in Sri Lanka. Women who are not married are a vulnerable group who experience poor access to cataract services and high cataract blindness. To “leave no one behind”, multi-faceted strategies are needed to address their needs.

The Aurolab Keratoprosthesis (KPro) versus the Boston Type I Kpro: 5-year Clinical Outcomes in 134 Cases of Bilateral Corneal Blindness

PURPOSE

To compare the clinical outcomes of Boston Type I keratoprosthesis (Boston Kpro) with its low-cost version, the Aurolab Kpro (auroKPro).

DESIGN

Retrospective comparative case series.

METHODS

This study included 134 eyes of 130 patients with severe bilateral corneal blindness but with wet ocular surfaces. The patients underwent either Boston Kpro (n = 78) or auroKPro (n = 56) implantation based on the device availability and patient's affordability. The primary outcome measurements were anatomical retention (defined as absence of device extrusion, exchange, or explantation) and functional recovery of 20/200 or better visual acuity at yearly time points until 5-years of follow-up.

RESULTS

Limbal stem cell deficiency was the most common indication (60.5%) for surgery, followed by multiple failed grafts (35%). Both groups were comparable at baseline with respect to indications for surgery and associated ocular co-morbidities (P > 0.05). The overall anatomical retention rates were similar in the Boston Kpro (55 of 78, 70.5%) and auroKPro (35 of 56, 62.5%) groups (P = 0.11). Kaplan-Meier survival rates at 5 years of follow-up were greater for the Boston Kpro with respect to both anatomical retention (63 ± 6% vs. 43.4 ± 10%, respectively; P = 0.057) and functional recovery (42.4 ± 6% vs. 32.2 ± 7%, respectively; P = 0.345), but these differences were not statistically significant. Complications such as intraoperative device breakage (7%) and postoperative extrusions (12.5%) were significantly more common with the auroKPro (P = 0.023).

CONCLUSIONS

Both the auroKPro and the Boston Kpro are effective treatment options for patients with severe bilateral corneal blindness. The auroKPro can be considered an alternative to the Boston Kpro when affordability or availability of the Boston Kpro is a limiting factor.

First Simultaneous Explantation and Re-Implantation of an Argus II Retinal Prosthesis System

A 59-year-old blind woman with retinitis pigmentosa had undergone implantation of an Argus II system without complications and took advantage of the system for 7 months. Due to a technical error of the system, the glasses of the prosthesis developed increased heat generation, making the use of the system unbearable. Because of the initial satisfaction and high motivation of the patient, it was decided to strive for an implant exchange. In a 4-hour surgery session, the implant was removed and a new system was implanted. Hereby, several critical surgery steps could be identified that are important to consider for future surgeries. Besides a strong fibrotic scarring of conjunctiva and tenon aggravating the extraction of the extraocular components, the preparation of the sclerotomy proved to be difficult for achieving water tightness. Furthermore, the extraction of the retinal tack and the repositioning of the new array were challenging steps. During the postoperative course, a severe hemorrhagic choroidal detachment occurred but resolved without surgical intervention. The implant was well-placed and showed good function. The exchange of an Argus II is feasible, however, with the challenge of hypotony and hemorrhage as well as possible fibrosis complicating the repositioning of the chip. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:462-465.].

Changing trends of blindness, visual impairment and cataract surgery in Bhutan: 2009-2018

Purpose

To obtain new rapid assessment of avoidable blindness (RAAB) data on the prevalence, causes and trends of blindness, visual impairment and cataract surgery; and compare the new 2018 data with the older RAAB 2009 data.

Methodology

The second nationwide RAAB used android based mRAAB technique and technology for data collection. Using the compact segment sampling probability proportionate to size, 5,050 participants from 101 clusters of 50 people aged 50 years and older were enrolled through house-to-house visits. Eligible participants received ophthalmic examination and interview by the ophthalmologist-led emuneration team as per the RAAB protocol.

Results

The age-sex adjusted magnitude of bilateral blindness in Bhutan was 1.0% (95% Confidence Interval, CI 0.5–1.4) with relatively higher prevalence in rural population (Odds Ratio, OR 1.5, p = 0.13) and women (OR 1.6, p = 0.06). Untreated cataract accounted for the most of blindness (53.8%), severe vision impairment (57.1%), and moderate visual impairment (65.3%); uncorrected refractive error was the main cause of early visual impairment (46.7%). Cataract Surgical Coverage was 86.1% with relatively better coverage in men (76.7% men; 73.1% female) and urban population (79.2% urban; 70.2% rural). Good cataract surgical outcome was achieved in 67.3% and leading cause of poor outcome was ocular comorbidity (43.6%). Accessibility was a significant barrier to the uptake of cataract surgical services.

Conclusion

There is a 33% reduction in blindness from 1.5% to 1.0%, since the first RAAB survey in 2009. In order to further reduce blindness and visual impairment, Bhutan should continue to implement long-term strategic action plan for eye health focused on strengthening primary eye care and comprehensive eye care service.

Optical Coherence Tomography in Patients With the Subretinal Implant Retina Implant Alpha IMS

BACKGROUND AND OBJECTIVE

The aim of this study was to assess changes in retinal structure and thickness after subretinal implantation of the Retina Implant Alpha IMS (Retina Implant AG, Reutlingen, Germany).

PATIENTS AND METHODS

Spectral-domain optical coherence tomography (SD-OCT) imaging was performed to assess the structure and thickness of the retina anterior to the microphotodiode array preoperatively, within 6 weeks and 6 months ± 1 month after implantation. Thickness measurements were performed using the distance tool of the built-in software. Three thickness measurements were performed in each of the four quadrants of the retina on the microchip within 6 weeks and 6 months ± 1 month after implantation.

RESULTS

The mean ± standard deviation change in retinal thickness from within 6 weeks to 6 months ± 1 month after implantation in all four quadrants combined was 24 μm ± 68 μm. None of the tested variables (location, time, or their interaction) had a statistically significant effect on the mean retinal thickness (P = .961, P = .131, and P = .182, respectively; n = 19).

CONCLUSION

The authors report on qualitative and quantitative findings in retinal structure in 27 patients after subretinal implantation of the Retina Implant Alpha IMS using OCT technology. No significant changes of retinal thickness could be observed in a period of 6 months after surgery. With more patients receiving subretinal implants and with advanced OCT technology, the data set will be extended to study possible changes in retinal structure in finer detail. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:993-999.].

Electronic retinal implants and artificial vision: journey and present

Retinitis pigmentosa and age-related macular degeneration are two significant causes of severe visual dysfunction. In both, the retinal photoreceptors degenerate, preventing successful conversion of light into electrical energy that is interpreted in the visual cortex as visual function. Artificial vision or visual function began over two centuries ago with the idea of creating artificial light pulses, or phosphenes, through cortical stimulation. The pursuit is now on to improve artificial visual function. Two retinal implants appear the most likely to succeed in the future having undergone multicentre human trials: the Argus II electronic epiretinal device (Second Sight Medical Products, CA, USA) and Alpha-IMS electronic subretinal device (Retina Implant AG, Germany). The trial results to date are encouraging with visual improvement and acceptable safety profiles reported for both devices. At present, the visual function generated by either device does not offer high enough resolution or acuity for a patient to regain a fully functional life. Despite this, both devices not only have the potential, but have actually improved the vision-related quality of life in a significant number of patients implanted. With this in mind, the economic argument is clear. Provided device-life is long enough, its cost should be acceptable for the obtained improvement in the quality of life. The aim of this Review Article is to assist those readers that may be considering offering any of these devices as a treatment for blindness in Retinitis Pigmentosa.