MyVisionTest News Archive
Mar 8, 2011
Smaller needles and beveled intravitreal injection technique offer superior results
To evaluate the amount of reflux and degree of pain with intravitreal injection (IVT) using 6 different types of syringes/needles and 5 techniques of scleral incision, including 3 modifications of a beveled scleral incision.
The risk of serious adverse events reported after intravitreal (IVT) injection injection is low. Endophthalmitis, which is infection inside the eye, is perhaps the most serious complication of IVT injection. Endophthalmitis has a reported prevalence of 0.2% per injection. Retinal detachment, iritis/uveitis, elevation of intraocular pressure (IOP), cataract, and intraocular hemorrhage are generally associated with injection of specific compounds and are infrequently attributed to the injection procedure itself. Intravitreal injection of drugs will frequently increase IOP. Occasionally a small drop of fluid will leak out of the eye at the injection site, this is known as reflux. This reflux leakage will lower the IOP, but also raises concerns regarding infection, loss of medication payload, or other injection-related complications. Careful attention to injection technique and appropriate postinjection monitoring are essential because uncommon injection-related complications may be associated with permanent vision loss.
This was a study conducted in 205 eyes of 205 patients. IVT of Avastin (bevacizumab) for retinal pharmacotherapy with 6 types of needles and 5 techniques of scleral incision. The severity of subjectively evaluated pain (0–10) and the width of the subconjunctival bleb arising from the vitreal reflux. Secondary outcomes were increase in intraocular pressure and complication rate.
The straight technique caused greater vitreal reflux than the beveled approaches, when compared individually or as a group. No difference in the severity of pain was found among all 5 types of incisions.
There was greater reflux with larger (26- and 27-gauge) needles in comparison to smaller (29- and 30-gauge) needles; however, the width of the needle significantly affected the degree of reflux only when using the nonbeveled incision.
The patients injected with the larger needles experienced more pain matched to the smaller needles.
No difference was found between the incision technique or width of subconjunctival reflux and the increase in intraocular pressure.
Postinjection events included transient mild uveitis, disease-related vitreous hemorrhage, foreign body sensation, conjunctival hemorrhage, and mild punctuate keratitis.
The investigators conclude that beveled scleral incision showed benefit in performing IVTs. Smaller needles caused less pain.
Read more...
J Ocul Pharmacol Ther. 2011 Feb 12. [Epub ahead of print]
Tags: drug delivery, Avastin, adverse drug effects

The risk of serious adverse events reported after intravitreal (IVT) injection injection is low. Endophthalmitis, which is infection inside the eye, is perhaps the most serious complication of IVT injection. Endophthalmitis has a reported prevalence of 0.2% per injection. Retinal detachment, iritis/uveitis, elevation of intraocular pressure (IOP), cataract, and intraocular hemorrhage are generally associated with injection of specific compounds and are infrequently attributed to the injection procedure itself. Intravitreal injection of drugs will frequently increase IOP. Occasionally a small drop of fluid will leak out of the eye at the injection site, this is known as reflux. This reflux leakage will lower the IOP, but also raises concerns regarding infection, loss of medication payload, or other injection-related complications. Careful attention to injection technique and appropriate postinjection monitoring are essential because uncommon injection-related complications may be associated with permanent vision loss.
The straight technique caused greater vitreal reflux than the beveled approaches, when compared individually or as a group. No difference in the severity of pain was found among all 5 types of incisions.
There was greater reflux with larger (26- and 27-gauge) needles in comparison to smaller (29- and 30-gauge) needles; however, the width of the needle significantly affected the degree of reflux only when using the nonbeveled incision.
The patients injected with the larger needles experienced more pain matched to the smaller needles.
No difference was found between the incision technique or width of subconjunctival reflux and the increase in intraocular pressure.
Postinjection events included transient mild uveitis, disease-related vitreous hemorrhage, foreign body sensation, conjunctival hemorrhage, and mild punctuate keratitis.
The investigators conclude that beveled scleral incision showed benefit in performing IVTs. Smaller needles caused less pain.
Read more...
J Ocul Pharmacol Ther. 2011 Feb 12. [Epub ahead of print]