Correlation between sub-Tenon's anesthesia and transient amaurosis during ophthalmic surgery.

PURPOSE: To verify the correlation between sub-Tenon's anesthesia and intraoperative visual loss in ophthalmic surgery. METHODS: Sixty-four patients underwent phacoemulsification combined pars plana vitrectomy under sub-Tenon's anesthesia. Participants were investigated about their light perception at several time points: before anesthesia, immediately after anesthesia, 10 min after anesthesia without any surgical intervention or microscope illumination, and after the whole surgery. Intraoperative amaurosis was determined as that a patient could not see any light from their operative eye. The incidence rate of amaurosis at different time points and among different anesthetists was analyzed. RESULTS: The rate of intraoperative amaurosis was 0%, 1.56%, 48.44%, and 95.31% at several time points, respectively: before anesthesia, immediately after anesthesia, 10 min after anesthesia without any surgical intervention or microscope light exposure during the interval, and immediately after the whole surgery, presenting a significantly time-dependent increase (P < 0.01). There was no correlation between the amaurosis and different diseases and anesthesiologists. The amaurosis was transient, and all operative eyes could perceive light on the first postoperative day. CONCLUSIONS: Sub-Tenon's anesthesia contributes to the intraoperative amaurosis during operation. Temporary interruption of optic nerve conduction by the anesthetic could be a credible explanation. The amaurosis is transient and reversible, requires no additional treatment, and should not be considered as a surgical complication.

Case Report: Intravitreal dexamethasone implant as adjuvant treatment for taxane-related cystoid macular edema.

Taxane-related cystoid macular edema (CME) is a rare complication of the taxoid medication, a chemotherapeutic drug. We report a 47-year-old Han Chinese man referred to our Eye Center for decreased vision with visual distortion in both eyes for two weeks. Two weeks prior, he received the last cycle of his six-monthly chemotherapy, including paclitaxel for hypopharyngeal malignancy. The best-corrected visual acuity (BCVA) was 0.4 OD and 0.1 OS. Macular optical coherence tomography showed significant bilateral CME, and fluorescein angiography (FA) revealed the fluorescein pooling at the late phase without leakage. Intravitreal 700 µg dexamethasone (DEX) implant was applied to the left eye and 13 days after to the right eye. Two months later, the macular morphology recovered to normal. One year after the first visit, the BCVA was 1.0 OD and 0.8 OS with standard macula on OCT. In conclusion, the intravitreal DEX implant might be an effective adjuvant treatment for taxane-related CME.

Incidence and impact factors of intraoperative loss of light perception under sub-Tenon's anesthesia in patients with macular diseases.

PURPOSE: To investigate the incidence and impact factors of intraoperative loss of light perception (LP) under sub-Tenon's anesthesia in patients with macular diseases. METHODS: Eighty-five consecutive patients received standard phacoemulsification combined pars plana vitrectomy (PPV) under sub-Tenon's anesthesia. At several checkpoints during the surgery (the end of phacoemulsification, the end of vitrectomy, and the end of surgery), participants were interviewed about whether they had LP or not after removing the influence of contralateral eye and the photo-bleaching effect. In patients treated with retinal photocoagulation, visual experience on laser flashes was evaluated. RESULTS: Under routine draping, no patients reported loss of LP at all the checkpoints. When the contralateral eye was tightly covered, the rates of LP loss were 84.7%, 97.6%, and 87.1% at the end of phacoemulsification, the end of vitrectomy, and the end of surgery, respectively. When the photo-bleaching effect was also removed, the rates of LP loss were 61.2%, 82.4%, and 56.5% at each checkpoint, respectively, and there were 87.1% (74/85) of patients reporting visual loss in at least one checkpoint. In addition, 76.9% (50/65) of patients could not feel laser flashes during retinal photocoagulation. CONCLUSION: Intraoperative loss of LP under sub-Tenon's anesthesia was a relatively common and reversible event. The conduction block of optic nerve by anesthetic mainly contributed to the visual loss during surgery. Photo-bleaching effect also has some effect on the LP evaluation. Surgeons need to inform and counsel the patients about the intraoperative loss of LP, to prevent any sudden panic attacks in them.