Adjunctive Greater Occipital Nerve Block for Pain Control in Medically Refractory Acute Primary Angle Closure: An...

Area of Science:

• Ophthalmology
• Pain Management
• Neurology

Background:

• Acute primary angle closure (APAC) is an ophthalmic emergency causing sudden intraocular pressure (IOP) spikes, severe pain, and headache.
• Current acute management focuses on IOP reduction, with limited research on preoperative analgesic strategies for medically refractory APAC.
• Greater occipital nerve block (GONB) is explored as a potential adjunctive treatment for pain relief in these cases.

Purpose of the Study:

• To evaluate the short-term efficacy and safety of adjunctive GONB in reducing pain intensity in patients with medically refractory APAC.
• To assess changes in headache intensity using the Numeric Rating Scale (NRS) before and after GONB administration.

Main Methods:

• A retrospective observational study involving 34 patients with medically refractory APAC who received GONB.
• Headache intensity was measured using an 11-point NRS at baseline, 30 minutes, and 60 minutes post-GONB.
• Longitudinal pain changes were analyzed using a linear mixed-effects model, with responder analysis for clinically meaningful pain relief.

Main Results:

• Mean NRS score decreased significantly from 7.8 at baseline to 3.6 at 60 minutes post-GONB (p < 0.001).
• A clinically meaningful pain reduction (≥3 points) was achieved by 79.4% of patients within 60 minutes.
• Time was a significant factor in pain reduction, indicating a rapid analgesic effect of GONB.

Conclusions:

• Adjunctive GONB demonstrated a rapid and significant reduction in pain intensity for medically refractory APAC patients.
• While promising, findings are limited by the retrospective, uncontrolled design and concurrent treatments.
• Further prospective, controlled studies are necessary to confirm the efficacy and role of GONB in APAC management.