Fundamentals of artificial intelligence for ophthalmologists.

PURPOSE OF REVIEW: As artificial intelligence continues to develop new applications in ophthalmic image recognition, we provide here an introduction for ophthalmologists and a primer on the mechanisms of deep learning systems. RECENT FINDINGS: Deep learning has lent itself to the automated interpretation of various retinal imaging modalities, including fundus photography and optical coherence tomography. Convolutional neural networks (CNN) represent the primary class of deep neural networks applied to these image analyses. These have been configured to aid in the detection of diabetes retinopathy, AMD, retinal detachment, glaucoma, and ROP, among other ocular disorders. Predictive models for retinal disease prognosis and treatment are also being validated. SUMMARY: Deep learning systems have begun to demonstrate a reliable level of diagnostic accuracy equal or better to human graders for narrow image recognition tasks. However, challenges regarding the use of deep learning systems in ophthalmology remain. These include trust of unsupervised learning systems and the limited ability to recognize broad ranges of disorders.

Laser therapy versus observation for symptomatic retinal artery macroaneurysms.

PURPOSE: The optimal management approach to retinal arterial macroaneurysms (RAM) is unknown. This paper compares long-term outcomes in RAM treated with laser therapy versus observation. METHODS: This is an IRB-approved retrospective study of patients with symptomatic RAM. Charts of patients with a diagnosis of RAM causing symptomatic visual loss were reviewed. Patients with less than 6 months follow up, other confounding diagnoses, or additional therapy beyond thermal laser were excluded. Statistical analysis was done using χ(2) or Student's t test as appropriate. RESULTS: Forty-eight patients with RAM were identified and 27 were included in the study (13 treated, 14 observed). Mean visual acuity in the observation group improved from 20/120 to 20/96 (p = 0.53) compared to 20/280 to 20/54 (p = 0.0003) in the treated group. Subgroup analysis showed that visual acuity in primarily hemorrhagic lesions treated with laser therapy improved by 1.21 logMAR compared to a loss of 0.11 logMAR (p = 0.002) in those that were observed. In primarily exudative lesions, both treated and observed lesions showed an improvement of 0.32 logMAR. No patients in the treatment group had a final visual acuity below 20/200 compared to four in the observation group. CONCLUSION: Treatment with direct laser photocoagulation was associated in this study with greater improvement in visual acuity and may decrease the risk of severe visual loss especially in primarily hemorrhagic RAM lesions. Compared to observation alone.

Presbyopia-correcting intraocular lenses and corneal refractive procedures: a review for retinal surgeons.

PURPOSE: To review the specific challenges and pitfalls that vitreoretinal surgeons may face when operating on eyes with presbyopia-correcting intraocular lenses or previous corneal refractive surgery. In addition, this review aims to familiarize vitreoretinal surgeons with specifications of currently available Food and Drug Administration-approved presbyopia-correcting intraocular lenses. METHODS: Review of current literature performed with PubMed for search terms "presbyopia," "correction," "IOL," "vitreoretinal," "challenges," and "surgical" both singly and in combination as well as closely related terms. RESULTS AND CONCLUSION: Specific intraoperative issues with presbyopia-correcting intraocular lenses that may be encountered include peripheral visualization, condensation, lens material issues particularly with silicone oil, decentration, Z-syndrome, and foveal image displacement. Every patient undergoing retinal surgery should also be asked about previous laser-assisted in situ keratomileusis/photorefractive keratectomy because those eyes require special attention to surface hydration and care to avoid epithelial removal if possible. Intracorneal ring segments and corneal inlays can cause effects similar to those of a small pupil. However, these can be managed with thorough preoperative evaluation and various intraoperative maneuvers. In addition, retinal physicians should be aware that macular disorders, such as age-related macular degeneration, may be exacerbated by potential loss of contrast sensitivity.

Comparison of intravitreal ranibizumab and bevacizumab for the treatment of macular edema secondary to retinal vein occlusion.

AIM: To compare the efficacy of ranibizumab and bevacizumab for macular edema due to retinal vein occlusion (RVO). METHODS: A retrospective study was conducted at a single academic institution. Eighty-one patients naïve to anti-VEGF therapy with RVO and macular edema were identified. Twenty-six eyes were treated with ranibizumab, 33 eyes with bevacizumab, and 22 eyes with bevacizumab then switched to ranibizumab (crossover). The main outcome was change in visual acuity at 3 months, 6 months, and final visit. RESULTS: The mean visual acuity improved from 20/80 to 20/40 in the ranibizumab (R) group and from 20/125 to 20/60 in the bevacizumab (B) group (P=0.66). The mean change in central subfield thickness (CST) was -186 and -212µm, respectively (P=0.69). Mean time between injections was 94±21.1d in the R group and 103.8±10.5d in the B group (P=0.78). In the crossover group, mean initial visual acuity was 20/125, reached 20/60 at crossover, and remained 20/60 at conclusion (P=0.91). CONCLUSION: Both ranibizumab and bevacizumab are effective for the treatment of RVO and appear to have similar visual and anatomic outcomes. Changing treatments from bevacizumab to ranibizumab did not result in further gains in visual acuity.

Bilateral subcutaneous emphysema from pressurized infusion during pars plana vitrectomy: a case report.

OBJECTIVES: To report a case of extensive subcutaneous emphysema introduced during vitrectomy while using an advanced feedback-controlled pressurized infusion system. METHODS: Clinical case report of a 56-year-old woman undergoing pars plana vitrectomy for rhegmatogenous retinal detachment of the left eye. The clinical and radiologic findings of the patient's eyes were documented. The mechanisms of feedback-controlled pressurized infusion devices were reviewed to explain the adverse events. A search of PubMed was conducted to look for any similar cases and/or discussion. RESULTS: In this surgical case, vitrectomy was completed with air-fluid exchange and a formed anterior chamber was observed with an estimated pressure of high teens to low 20s by the surgeon. After the undraping, the patient was noted to have severe facial crepitus extending to the clavicles. Immediate chest X-ray was done, followed by computed tomography, confirming orbital and subcutaneous emphysema, as well as the presence of perfluoro-N-octane in the left orbit. CONCLUSION: Integrated pressurized infusion devices using feedback sensors allow for a sophisticated method of maintaining intraocular pressure and globe formation. However, inadvertent or occult globe rupture may lead to disruption of feedback control and subsequent high rates of infusion. As the infused substances exit the site of rupture, they can lead to extensive extraocular gas or fluid accumulation, and we report a case of severe bilateral subcutaneous emphysema as a result.