Kleine-Brueggeney Maren, Priemer Fritz, Konietschke Frank, Theiler Lorenz, Greif Robert
Department of Cardiac Anesthesiology and Intensive Care Medicine, Deutsches Herzzentrum der Charité (DHZC), Augustenburger Platz 1, 13353, Berlin, Germany.
Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt- Universität zu Berlin, Berlin, Germany.
BMC Ophthalmol. 2025 May 13;25(1):286. doi: 10.1186/s12886-025-04107-7.
This prospective, single-blind, placebo-controlled trial examined the effects of intravenous delta-9-tetrahydrocannabinol (d9-THC) on the pupillary light reflex and pupil size in volunteers not regularly consuming cannabis.
With ethics committee approval and written informed consent, healthy cannabis-naïve or abstinent volunteers were included. Fifteen volunteers received an intravenous bolus of d9-THC and four received placebo. Pupillary reaction and pupil size were assessed by pupillography before and for 5 h after drug administration. Primary outcome was relative amplitude. Secondary outcomes were latency, velocity of contraction, constriction time, contraction amplitude, and pupil diameter.
Pupillographic measurements were significantly altered by THC: The relative amplitude was significantly reduced with a global difference between groups (p = 0.001). The relative amplitude significantly declined at 20 min after THC administration (23.5-15.0%), and stayed constant in after placebo (27.5-28.1%). Constriction time was significantly reduced with a significant global time effect (p = 0.002), global group effect (p = 0.001), and global effect of the interaction between group and time (p < 0.001). Contraction amplitude was reduced with a significant global group effect (p < 0.001). Latency and velocity of contraction demonstrated a statistically non-significant increase. Pupil size decreased after THC administration.
Pupillography can objectively detect effects of THC on the human eye. In cannabis-naïve or abstinent volunteers THC dampens the pupillary light reflex which could result in an increased sensitivity to light. THC does not cause mydriasis, but rather miosis. These results can substantiate questions regarding liability and driving ability under the influence of THC.
The study was prospectively registered at www.isrctn.com (registration number ISRCTN53019164) on 14/04/2010.
这项前瞻性、单盲、安慰剂对照试验研究了静脉注射Δ⁹-四氢大麻酚（d9-THC）对不经常吸食大麻的志愿者瞳孔光反射和瞳孔大小的影响。
在获得伦理委员会批准并取得书面知情同意后，纳入健康的从未吸食过大麻或已戒除大麻的志愿者。15名志愿者接受了静脉推注d9-THC，4名接受了安慰剂。在给药前及给药后5小时通过瞳孔描记法评估瞳孔反应和瞳孔大小。主要结局指标为相对幅度。次要结局指标为潜伏期、收缩速度、收缩时间、收缩幅度和瞳孔直径。
THC使瞳孔描记测量结果发生了显著改变：相对幅度显著降低，组间存在总体差异（p = 0.001）。THC给药后20分钟相对幅度显著下降（从23.5%降至15.0%），而安慰剂组相对幅度保持稳定（从27.5%至28.1%）。收缩时间显著缩短，存在显著的总体时间效应（p = 0.002）、总体组效应（p = 0.001）以及组与时间交互作用的总体效应（p < 0.001）。收缩幅度降低，存在显著的总体组效应（p < 0.001）。潜伏期和收缩速度虽有增加，但无统计学意义。THC给药后瞳孔大小减小。
瞳孔描记法可客观检测THC对人眼的影响。在从未吸食过大麻或已戒除大麻的志愿者中，THC会减弱瞳孔光反射，这可能导致对光的敏感性增加。THC不会引起瞳孔散大，而是导致瞳孔缩小。这些结果可以证实关于THC影响下的责任认定和驾驶能力的问题。
该研究于2010年4月14日在www.isrctn.com上进行前瞻性注册（注册号ISRCTN53019164）。
