English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Dear Editor, W e read with interest the article by Chen [1] on the visual impact of sub-Tenon anesthesia during combined phacoemulsification and vitrectomy surgery. The authors reported that 93.3% of patients in the study experienced loss of perception of light at least during one of the surgical steps after the contralateral eye was covered intraoperatively[1]. Most of the patients (81%) reported losing light perception between 6min and 30min from the commencement of the surgery. While it is not unusual for patients to experience loss of light perception during vitrectomy, Chen [1] have reported a higher incidence of loss of light perception compared to other similar papers. An earlier study of patients undergoing vitreous surgery performed under regional (peribulbar or retrobulbar) anesthesia reported that 29.2% of patients experience transient loss of light perception, while 24.6% of patients experienced no light perception throughout the entire duration of the surgery[2]. Among studies of patients undergoing phacoemulsification, the rate of loss of light perception varied from 0 to 20%[3]. The loss of light perception in ophthalmic surgery is not only limited to phacoemulsification and vitrectomy surgery. Among patients who underwent laser keratomileusis (LASIK) surgery, 75.6% also experienced loss of light perception during corneal flap fashioning [4]. This was higher in the eyes where the Zyoptix XP microkeratome was used, compared to those who underwent intralase during corneal flap fashioning (90.2% 61.0%, =0.004). In that study, 62% of patients also reported lost of light perception during vacuum suctioning. The higher incidence of loss of light perception reported by Chen [1] may be due to various factors such as differences in demographics, or disease severity in this cohort. Regardless of the reason, an important consideration is that many patients may not expect to experience no light perception during an ophthalmic surgery. In a study by Ang [5] on patient's expectation and experience of visual sensations during phacoemulsification, 36.7% of patients expected to experience at least light perception during the surgery, while 24.5% of them were unsure what to expect. Among patients expecting to see light, the loss of light perception may be frightening , as these patients may assume that complications have occurred during the surgery. Fear experienced by patients is undesirable as it may cause patients to be uncooperative intraoperatively, and may also trigger a sympathetic stress response [7]. This highlights the importance of counseling the patients pre-operatively on what to expect. In addition to no light perception, many patients also experienced various other visual sensations such as color, movement, flashes and instruments . As many as 19.4% of the patients found their visual experience frightening[5]. It will be equally important to highlight these to patients during their pre-operative counseling. In summary, we congratulate the authors on their paper, and suggest that patients undergoing ocular surgery should be counseled pre-operatively on the possibility of intra-operative visual sensations, including loss of light perception. ACKNOWLEDGEMENTS Foundation: Supported by the National Healthcare Group Clinician Scientist Career Scheme Grant CSCS/12005. Conflicts of Interest: Li KZ, None; Tan CS, receives travel support from Bayer, Heidelberg Engineering and Novartis. REFERENCES

Comment on visual impact of sub-Tenon anesthesia during combined phacoemulsification and vitrectomy surgery