Subjective visual perceptions during vitreoretinal surgery under local anaesthesia

Abstract

Purpose To evaluate the visual experiences of patients during vitreoretinal surgery under local anaesthesia (LA). Methods Prospective questionnaire survey of 80 patients within 30 min of completion of vitreoretinal surgery under LA. Preoperative visual acuity, surgical procedure and its duration, efficacy of the local block, as well as intraoperative perceptions of flashes, colours, movements, and seeing instruments were documented. Results A sub-Tenon's block was performed in 62/80 (77.5%) and a peribulbar block in the remainder. Overall, 72 (90%) of patients perceived light at some stage during their surgery. Of these, 51 (70.83%) observed movements, 45 (62.5%) saw colours, 38 (52.77%) saw instruments, and 24 (33.33%) saw flashes. The commonest observations were colourful swirls, black pipes, and the colour red. Most patients found these experiences pleasant or bearable; two found them frightening, and four would like to have been warned preoperatively about them. Preoperative visual acuity, diagnosis, gender of the patient, degree of akinesia, and the duration of surgery did not associate with visual perceptions. Logistic regression analysis showed that younger people were more likely to experience flashing lights (P ¼ 0.03) and to see instruments (P ¼ 0.04), patients having a sub-Tenon's block to perceive light (P ¼ 0.005), and those who did not receive awake sedation were more likely to see instruments (P ¼ 0.04). Conclusions Visual experiences are common during vitreoretinal surgery undertaken under LA. Where appropriate, patients should be forewarned about these experiences and reassured that they are not normally frightening.

Subjective visual perceptions during vitreoretinal surgery under local anaesthesia

“…2,3 The variation in the proportion of patients frightened is similar to that described during cataract surgery, which ranges from 3 to 19.4%. 4 There are many possible reasons for this variation between studies, including cultural differences, as well as the previous operative experience of the patients. In the cohort of 65 patients described by Tan et al, 2 61 (93.8%) were undergoing vitreoretinal surgery for the first time.…”

“…It has been suggested that previous ocular surgery may serve as a 'practical' form of counselling on the range of possible intraoperative visual experiences. 4 A study on patients undergoing cataract surgery 5 reported that 15.8% of patients undergoing surgery for the first time were frightened by their intraoperative visual sensations, compared with only 6% for those having surgery to the second eye.…”

“…We agree that there is a variation in the number of patients who are frightened by intra-operative VPs, but overall the percentage of such patients is small. It is appropriate to state that the majority of patients find VPs during intra-ocular surgery bearable; some find them even pleasant [2][3][4] and one has found them good enough to write a poem about them. 5 In our study, 52/72 (72.22%) of patients described their VPs as 'bearable', and only two patients (2.7%) thought that they were 'frightening'.…”

Reply to Dr Tan

“…We agree that there is a variation in the number of patients who are frightened by intra-operative VPs, but overall the percentage of such patients is small. It is appropriate to state that the majority of patients find VPs during intra-ocular surgery bearable; some find them even pleasant [2][3][4] and one has found them good enough to write a poem about them. 5 In our study, 52/72 (72.22%) of patients described their VPs as 'bearable', and only two patients (2.7%) thought that they were 'frightening'.…”

Visual perceptions induced by intravitreous injections of therapeutic agents

“…3 Indeed, some authors are even using IVT therapeutic agents for relatively rare disorders, such as central serous chorioretinopathy. 3 Patients' visual perceptions and experiences induced by frequently performed ophthalmic surgical procedures, such as cataract surgery (under topical [10][11][12][13][14][15] and regional anesthesia [11][12][13][14]16,17 ), glaucoma filtration surgery, 18 and vitreoretinal surgery, [19][20][21][22] are well documented. Indeed, the beneficial effect of preoperative counseling with respect to known and anticipated visual experiences during phacoemulsification cataract surgery, under topical anesthesia, in terms of reducing patients' fear, has been described.…”