Novel Intravitreal Injection technique fast with better patient acceptance: Study

Utilizing allied health professionals for IVI administration has increased treatment capacities. Novel techniques have been described that deliver faster, safer and more accurate injections. Various assistive devices may improve efficiency and patient experience. The Intravitreal Injection Guide (IIG) is a recently introduced single-use, IVI assistive instrument that features (1) a single blade lash guard; (2) a curved footplate with a distance marker; (3) a cylindrical chamber which allows controlled transscleral needle insertion, and (4) a handle.

This study carried by Uy and Artiaga aimed to compare the effectiveness, procedural time, patient acceptability, and safety of the IIG versus conventional dual blade speculum (DBS) for administering IVI injections.

This was a prospective, single-center, randomized clinical trial of 200 adult eyes receiving intravitreal medications for various indications. Eyes were assigned (1:1) to undergo IVI using either an intravitreal injection guide (IIG) (n= 100) or conventional dual blade speculum plus surgical caliper (DBS) (n=100). All IVI were administered using a 30-gauge needle placed 4 mm posterior to the inferior limbus. The main outcome measures were rate of successful IVI administration, procedure time (seconds) as measured by a stopwatch from application to removal of IIG or DBS, patient preference for IVI technique and adverse events.

• The two groups were similar in terms of mean age (P=0.398), laterality (P=0.671), indication for treatment (P=0.175) and medication type (P=0.489).

• All IVI procedures were successfully completed in both groups.

• The mean procedure time was shorter using the IIG (9.94 ± 2.87 seconds) versus DBS (21.85 ± 7.25 seconds) technique (P ≤ 0.01).

• The incidence of post-injection subconjunctival hemorrhage was higher when the DBS was applied (OR = 2.35, 95% CI = 1.22–4.53).

• Patients with previous history of IVI preferred the IIG over the DBS. No other injection-related adverse events were observed in both groups.

The IIG has also been reported to provide a slightly less painful IVI experience compared to conventional techniques and generated good patient feedback. The post-injection survey of patients who received prior IVI using conventional DBS device demonstrated their preference for the IIG on the basis of improved comfort. The study results further demonstrate that the IIG device can shorten the procedural time and may be associated with a lower incidence of post-injection SCH.

The IIG is designed to facilitate the injection process. A single motion exposes the injection site, identifies the injection site and guides the needle as to the appropriate injection angle and depth. As a result, the procedure time can be shortened. As the device is disposable, the support staff also saves time by not having to sterilize instruments for succeeding patients. Time and motion studies like this are helpful for optimizing practice efficiency.

Compared to the DBS which applies pressure on both upper and lower eyelids, the single blade IIG decreases the amount of applied pressure as only one eyelid needs to be pushed away. Depending on patient-specific factors (eg small palpebral apertures, uncooperative patients), more effort may be required to apply a DBS resulting in more patient discomfort. Compared to the DBS, authors found that the IIG is easier to apply as only one eyelid needs to be engaged.

"In this study, use of the IIG decreased the procedural time by half for every case. While this decrease of about 10 seconds does not seem like much, these 10 seconds consist of high value physician time. A physician or injector can essentially double the number of IVI completed in the same amount of time thereby enhancing their productivity. In an optimized set up, the support staff can prepare a series of eyes for IVI and the physician or injector can then inject these eyes rapidly, accurately and safely in an assembly line fashion with appropriate time out procedures. Using the IIG and an assembly line set up, we can typically complete injection of 4 to 5 eyes within a minute."

Future innovations will continue to improve the efficiency and safety of IVI. In the near horizon, prefilled syringes will shorten the drug preparation step, while longer-acting drugs, sustained release or depot preparations can lessen injection frequency. In the long term, robotic assistive devices may lead to IVI automation. This study demonstrates that both DBS and IIG are effective means of administering IVI. Additionally, the IIG reduces procedure time, decreases the incidence of cosmetically displeasing SCH, lessens procedural discomfort and may improve clinical efficiency and cost effectiveness of the IVI procedure. The IIG is likely to decrease patient injection anxiety and improve efficiency in practices with significant IVI volumes.

Source: Uy and Artiaga; Clinical Ophthalmology 2021:15