Purpose <p>To evaluate the feasibility and preliminary safety of a plungerless intravitreal injector device (IPLID) adapted for aqueous humor aspiration during anterior chamber paracentesis.</p> Methods <p>In this proof-of-concept pilot study, ten consecutive eyes undergoing diagnostic anterior chamber paracentesis with the IPLID were prospectively enrolled and compared with a retrospective cohort of ten eyes that underwent conventional syringe-based aspiration. Procedures were performed under slit-lamp visualization. Primary outcomes included feasibility and procedure duration. Secondary outcomes included aspirated volume, intraocular pressure (IOP) changes, wound integrity, patient discomfort (visual analogue scale), and surgeon-reported usability.</p> Results <p>All procedures were successfully completed without intraoperative complications. The device achieved consistent aqueous humor aspiration (48 ± 5 µL) compared with greater variability using conventional methods (59 ± 17 µL). No anterior chamber instability or hypotony occurred. Wounds were self-sealing in all cases, whereas two control cases required bandage contact lenses. Procedure time was shorter and patient discomfort lower with the IPLID (<i>p</i> &lt; 0.01). No adverse events were observed during one-week follow-up.</p> Conclusions <p>The plungerless intravitreal injector device appears to be a feasible and safe alternative for anterior chamber paracentesis, enabling controlled and reproducible aqueous humor sampling with improved procedural consistency and patient comfort. Larger prospective studies are warranted to confirm these findings and assess long-term safety.</p>