Using smartphone-delivered stereoscopic vision in microsurgery: a feasibility study.

BACKGROUND: Many surgical specialties are increasingly looking towards robot-assisted surgeries to improve patient outcome. Surgeons conducting robot-assisted operations require real-time surgical view. Ophthalmic robots can lead to novel vitreoretinal treatments, such as cannulating retinal vessels or even gene delivery to targeted retinal cells. This study investigates the feasibility of smartphone-delivered stereoscopic vision for microsurgical use. METHODS: A stereo-camera, connected to a laptop, was used to capture the 3D view from a binocular surgical microscope. Wi-Fi connection was used to live-stream the laptop display onto the smartphone screen wirelessly. Finally, a Virtual Reality (VR) headset, which acts as a stereoscope, was used to house the smartphone. The headset wearer then fused these images to achieve stereoscopic perception. RESULTS: Using smartphone-delivered 3D vision, the author performed a simulated cataract extraction operation successfully, despite a time lag of 0.354 s ± 0.038. To the author's knowledge, this is the first simulated ophthalmic operation performed via smartphone-delivered stereoscopic vision. CONCLUSIONS: Microscopic output in 3D with minimal time lag can be readily achievable with smartphones and VR headsets. Uncoupling the surgeon from the operating microscope is required to achieve tele-presence, an essential step in tele-robotics. Where operating theatre space is a concern, head-mounted displays may be more convenient than 3D televisions. This 3D live-casting technique can be used in teaching and mentoring settings, where microsurgeries can be live-streamed stereoscopically onto smartphones via local Wi-Fi network. When connected to the internet, microsurgeries can be broadcasted live and viewers worldwide can see the surgeon's view wearing their VR headsets.

Effect of primary Phacoviscocanalostomy/ Viscocanalostomy on intraocular pressure of normal tension glaucoma patients: 3-year results.

BACKGROUND: The objective of this study was to evaluate the efficacy of Viscocanalostomy/Phacoviscocanalostomy (VC/PVC) in lowering intraocular pressure (IOP) in Normal Tension Glaucoma (NTG) patients. METHODS: Retrospective electronic database review of patients who underwent VC/PVC for NTG between December 2009 and November 2011 at Stanley eye unit in Abergele Hospital. Goldmann applanation tonometry (GAT) was used for all IOP measurements which were taken at the time of listing for surgery and at 1 day, 1 week, 1 month, then 3-monthly up to 1 year, then half-yearly up to 3 years post operatively. Statistical analysis was performed using unpaired t-test. A P value of <0.05 was accepted as the level of significance. RESULTS: Operations were performed on 94 eyes from 67 patients over the study period. The mean age at the time of surgery was 76.4 years. Pre-operative IOP was 17.75 ± 2.19 mmHg (range 12-21 mmHg). 3 year follow-up showed a mean IOP of 13.41 ± 2.22 mmHg (range 8-18 mmHg). By year 3, 17 patients needed laser goniopuncture and 25 patients needed antiglaucoma drops. IOP was reduced by 24.4% at 3 years post-surgery, which was statistically significant (p < 0.0001). CONCLUSIONS: From our results, which show a 24.5% reduction in IOP at 3 years with 12% complication rate, we propose that a logical surgical management for NTG patients would be viscocanalostomy, thereby keeping trabeculectomy as an alternative.

Bilateral corneal injury after face-paint application to upper eyelids.

A 40-year-old woman with no known medical conditions or allergies presented with severely painful, watery eyes and blurred vision. She reported topical application of face-paint onto both upper eyelids prior to attending a Halloween party. She subsequently noticed a burning sensation, epiphora and misty vision within a few hours. On examination, bilateral large corneal epithelial defects were highlighted with fluorescein dye under cobalt-blue light. Antibiotic ointment, mydriatic and sodium ascorbate 10% eye-drops were given, and patient was advised to keep the eyelids shut to promote healing. No corneal defects were visible by day 4 and the patient was discharged with vision recovering to normal levels.

Homonymous hemianopia in the primary antiphospholipid syndrome.

A woman aged 26 years was referred by her GP to the eye casualty department with sudden-onset left homonymous hemianopia and right-sided headache. Full ophthalmic examination was normal with the exception of a left homonymous hemianopia confirmed with automated perimetry. Urgent CT imaging revealed a non-haemorrhagic cerebral infarct in the right parieto-occipital region. Subsequent blood tests confirmed a diagnosis of antiphospholipid syndrome with positivity in IgG anticardiolipin antibody, IgG anti-ß2-GP1 antibody and the Lupus anticoagulant screen. MRI revealed extensive congenital abnormality at the Circle of Willis, affecting the right half of circulation. The unique dual pathologies may explain her predisposition to right-sided cerebral infarctions. This case highlights a rare but potentially fatal cause of visual disturbance in a young patient, and the importance of the multidisciplinary team approach in diagnosis and management.