Dear Editor, I n this case, we discuss a teenager who experienced severe eye pain and elevated intraocular pressure (IOP) caused by reverse pupillary block, which was successfully resolved using Neodymium-doped yttrium aluminum garnet (Nd:YAG) laser peripheral iridotomy (LPI). In general, the mechanism of IOP elevation including 1) the iris closely contacting the anterior surface of crystalline lens, leading to the pupillary block, 2) trabecular pathway lesions that increase resistance to aqueous outflow. Such acute IOP increases are commonly seen in closed-angle glaucoma, typically affecting older women with shorter axial lengths and shallower anterior chambers[1-2]. In the prodromal phase, symptoms may include mild eye discomfort and headaches, while major acute attacks can cause severe eye pain, intense headaches, nausea, and vomiting. In this case, the teenager male patient suffered from eye pain, along with nausea and vomiting, all signs of a sudden rise in IOP. His IOLMaster measurements indicated a longer eye axial length and a deeper anterior chamber. Ultrasound biomicroscopic (UBM) imaging showed that his iris was concave backwards and touching both the lens and zonules.