Needle size in intravitreal injections – pain evaluation of a randomized clinical trial

Abstract

ABSTRACT.Purpose: To evaluate the influence of the needle size used for intravitreal (IVT) injections on patients' pain experience in a randomized, double-armed, singleblinded, clinical trial. Methods: Patients included were randomized to have an IVT injection performed with a 27-gauge needle (group 1) or with a 30-gauge needle (group 2). The topical anaesthesia before the injection was standardized. Immediately after the injection, patients were asked to grade their pain using the visual analogue scale (VAS) and the Wong-Baker FACES scale. The main outcome measure was the pain score assessment. Cofactors analysed were patients' demographics (age and gender) and clinical characteristics (such as the number of previous IVT injections). In addition, scaled surgeon's questionnaires to assess the IVT injection procedure were evaluated. For statistical analysis, a regression model was used. Results: The data of 208 patients (group 1: 104 patients; group 2: 104 patients) were analysed. There was no significant difference in the VAS pain scores (p > 0.18) and in the Wong-Baker pain scores (p > 0.59) between both treatment groups. Gender (p = 0.0288) and the number of previous IVT injections (p = 0.0028) significantly influenced the VAS pain scores (p < 0.05). Female patients and patients with a history of previous IVT injections had higher pain scores. The surgeon's questionnaire showed an overall preference towards the use of a 30-gauge needle for IVT injections. Conclusion: The use of a 30-gauge needle for IVT injections showed no significant effect in pain relief compared to the use of a 27-gauge needle. However, a 30-gauge needle was preferred by all surgeons.

Which quadrant is less painful for intravitreal injection? A prospective study

“…Contrary to previous studies, we found that sex was a significant contributor, such that females reported higher pain scores during IVB (p = 0.001) even after adjusted in multivariate regression analysis (Table 3). Similarly, Haas et al [37] reported higher VAS pain scores in females. They suggested that females are more sensitive than males to noxious stimuli and have lower levels of stress-induced analgesia.…”

Intravitreal Delivery of Melatonin Is Protective Against the Photoreceptor Loss in Mice: A Potential Therapeutic Strategy for Degenerative Retinopathy

“…These features will facilitate the drug delivery under direct visualization and subsequent noninvasive imaging in vivo. Intravitreal injection is a precise delivery approach which can maximize the drug intensity within eyeball (Haas et al, 2016). After injected into the vitreous humor, the therapeutic agents can touch a substantial fraction of the outer retina, avoiding the side effects on unwanted organs.…”

Intravitreal Injections: Minimizing the Risk and Maximizing Comfort

“…Studies have shown that needle diameter is correlated to discomfort during the injection process, with comfort levels improving as needle size decreases from 26 to 33 gauge. [34][35][36][37]…”