Angled transscleral intravitreal injection: a crossover study.
OBJECTIVE
The perfect intravitreal injection delivers an exact amount of medication with the least risk to vision and the eye. We examined 2 different methods of intravitreal injection to determine if an angled transscleral entry for intravitreal injection results in less egress of intravitreal contents, including medication.


METHODS
In a crossover controlled trial at an outpatient clinical facility within a major ophthalmology referral center, we treated 10 patients. The surgical technique involved injecting 0.05 mL of bevacizumab injected in one eye by both an orthogonal (straight in) and oblique (angled) technique. The intraocular pressure (IOP) was measured immediately before and after each monthly injection.


RESULTS
Orthogonal injections raised the IOP significantly less (mean 24.6 mm Hg or 126%) than oblique injections (29.6 mm Hg or 152%) (p = 0.045). There were no reported differences in injection-related pain or adverse effects between the techniques.


CONCLUSIONS
Oblique or angled injections caused a larger IOP rise than straight or orthogonal injections. This finding suggests that oblique injections are self-sealing, deliver a higher dose of medication, or prevent vitreous reflux as well as close a potential portal of entry for pathogens.
The New York Eye Cancer Center, New York - USA.
Mitul C
MC
Mehta
Paul T
PT
Finger
D000368:Aged; D000369:Aged, 80 and over; D020533:Angiogenesis Inhibitors / Q000008:administration & dosage* / Q000627:therapeutic use; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage* / Q000627:therapeutic use; D000068258:Bevacizumab; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects / Q000502:physiology; D058449:Intravitreal Injections / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012164:Retinal Diseases / Q000188:drug therapy*; D012590:Sclera; D014065:Tonometry, Ocular; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors; D014822:Vitreous Body / Q000187:drug effects*
D020533:Angiogenesis Inhibitors; D061067:Antibodies, Monoclonal, Humanized; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D000068258:Bevacizumab