Trabecular meshwork pigmentation is a manifestation of the clinical diagnosis of pigmentary glaucoma. Pigmentary glaucoma is a secondary open-angle glaucoma caused by pigmentation of the anterior segment of the eye. So how is the disease examined clinically? There is little discomfort or visual disturbance in the early stages, and some patients have intermittent eye distention and blurred vision secondary to pigmentary glaucoma. The vast majority are detected inadvertently during a physical examination, which may explain why a significant number of patients already have combined glaucoma at the time of initial diagnosis. Studies of Caucasians have shown that 10% of patients with PDS progress to uveitic glaucoma after 5 years of diagnosis, and this percentage increases to 15% after 15 years. Pigment granule deposits on the iris surface and posterior cornea are not easily detected initially, whereas in Caucasians they are relatively easy to detect, facilitating early diagnosis of PDS. Studies have shown that IOP >21 mmHg at diagnosis is the most significant risk factor for conversion to pigmentary glaucoma in patients with PDS. In addition, being male and black is also a risk factor for conversion. The main signs are posterior corneal vertical fusiform pigment granule deposition (Krukenberg pigment shuttle), midperipheral posterior iris concavity, pigment granule deposition on the anterior surface of the iris, and pigment granule deposition on the anterior and posterior surfaces of the lens and the suspensory ligament. In Caucasian patients, transillumination of the posterior surface of the iris can occur in areas of pigment loss, called “iris transmission defects” (ITD). The trabecular meshwork is uniformly pigmented (early on, it may appear lighter above and heavier below) on atrial angioscopy. Occasionally, a band of pigment granules (Sampaolesi line) is seen in front of the Schwalbe line, especially in the lower atrial angle. In patients with dilated pupils, a ring of pigment particles is seen at the attachment of the suspensory ligament of the lens and/or the Weiger ligament of the posterior lens capsule (the anterior vitreous membrane ligament), called the Zentamayer ring or Scheie line. When the Weiger ligament is partially or completely detached, the posterior atrial water communicates with the Berger space behind the lens, and pigment particles can enter the Berger space with the atrial water and deposit on the posterior lens capsule, resulting in vision loss. the Krukenberg pigment shuttle, trabecular meshwork pigmentation, and iris transmission defect are the most characteristic clinical signs of PDS, called “pigmentation spread triad”, which is important for the clinical examination of PDS.