Pigmented glaucoma

Introduction to pigmented glaucoma Pigmented glaucoma (PG) is a kind of glaucoma caused by the posterior iris of the middle part of the iris and contact with the lens suspensory ligament, friction caused by the loss of pigment particles on the posterior surface of the iris, deposited in the trabecular meshwork, and blocked by the outflow of aqueous humor. The disease is more common in men aged 25 to 40 years old, and has a certain family aggregation. Caucasian patients are autosomal dominant, and related genes are located on chromosome 7. Most of the patients were myopia, deep anterior chamber, wide angle of the anterior and posterior fossa. The currently recognized pathogenesis is that the iris in the middle part of the iris is backward. When the pupil moves and adjusts, the iris and the suspensory ligament underneath the friction, and the pigment particles fall into the anterior chamber, sinking behind the cornea, the suspensory ligament and the trabecular meshwork. basic knowledge The proportion of illness: 0.02% - 0.04% Susceptible people: no special people Mode of infection: non-infectious Complications: ocular hypertension

Causes of pigmented glaucoma

(1) Causes of the disease

Unclear etiology may be associated with abnormal development of iris pigment epithelium (atrophy or degeneration).

(two) pathogenesis

The mechanism of pigment dissemination has proposed two theories of developmental and mechanical. The pathological study of the iris in this disease found that the iris pigment epithelium is focally atrophied, the pigment is reduced, the melanin production is significantly delayed, and the pupil dilated muscle hyperplasia, suggesting the iris. Pigment epithelial dysplasia (atrophy or degeneration) is a basic defect of pigment dissemination. Iris fluorescein angiography shows that iris vascular distribution defects and vascular hypoperfusion (the latter can occur before pigment dissemination), suggesting iris mesoderm support Tissue congenital developmental defects, autosomal dominant inheritance pattern of this disease, it has been reported that both brothers suffer from pigmentary glaucoma and extensive retinal pigment epithelial dystrophy, peripheral iris depression, iris root length, iris relaxation, significant scleral fistula Morphological abnormalities such as the ciliary body band, the later iris attachment and the rich iris protrusion seem to support the etiology of the genetic or developmental defects of the disease.

Pigmented glaucoma prevention

1. Maintain a good mood and avoid excessive emotional fluctuations. The most important predisposing factors for glaucoma are long-term bad mental stimulation, temper, depression, anxiety, and panic.

2, life, diet and living rules, work and rest, moderate physical exercise, do not participate in strenuous exercise, maintain sleep quality, diet light and nutritious, non-smoking wine, strong tea, coffee, appropriate control of water intake, can not exceed 1000-1200ml per day , disposable drinking water should not exceed 400ml.

3, pay attention to eye hygiene, protect the eyes, do not read under strong light, the dark room stay time can not be too long, the light must be soft enough, do not overuse the eye.

4, comprehensive conditioning of systemic complications.

5, pay attention to the impact of drugs.

6, women's amenorrhea, menopause, and dysmenorrhea, but elevated intraocular pressure should be highly valued, such as glaucoma manifestations during menstruation, should promptly see a specialist.

7, glaucoma family and risk factors, must be reviewed regularly, once there are signs of the disease, must actively cooperate with treatment to prevent sudden loss of visual function.

Pigmented glaucoma complications Complications, high ocular hypertension

Fundus damage caused by high intraocular pressure.

Symptoms of pigmented glaucoma Common symptoms High intraocular pressure lens protein escapes "chicken blindness" or "bird blindness" Iridoid trabecular meshwork pigmentation pupillary deformation iris defect eyeball tremor pupillary asymmetry

The key to PDS/PG diagnosis is a series of characteristic clinical manifestations: pigmentation in the anterior and posterior segments, iris shape and transillumination defects.

1. Cornea: Typical pigmentation can be seen by microslit lamp-Krukenberg shuttle: pigmentation is located in the central region of the posterior wall of the cornea, 0.5-3.0 mm wide, 2-6 mm long, perpendicular and tends to the middle slightly, the shuttle is usually The base-down triangle, which is the result of convection of the aqueous humor in the anterior chamber from the nasal side and the medial side of the temporal side. Atypical can be biased to one side or obliquely. The Krukenberg shuttle was first discovered by PDS/PG. Abnormally, this shuttle is common, but not every case.

Histological studies have shown that pigment particles inside and outside the cell are engulfed by corneal endothelial cells. If the submucosa is found under the slit lamp and there is a serious concentric circle of peripheral corneal endothelial pigment under the nose, it indicates that there is also a serious pigment in the trabecular meshwork. Occasionally, without the keratomileusis, the Schwalbe line can be seen. Although there is pigmentation after the cornea, the corneal endothelial cell count of the PDS is normal, and the corneal center thickness is usually normal, indicating that the corneal endothelial cells function. damage.

2. Iris

(1) anterior surface pigmentation: pigment granules mainly accumulate in the dilated groove of the iris center, especially in the blue iris, but the same incidence occurs in the dark iris, and the scattered pigment rarely causes the iris color to occur. Change, if the binocular pigment spread is asymmetric, iris coloration can occur, and pigmentation on the iris surface can be expressed as scattered pigment particles or pigment-filled phagocytic cells.

(2) Appearance: Many PG patients in the early stage of the disease, iris keratoscopy can be found in the surrounding iris is slightly depressed, the matrix is thin and cystic, due to the anterior chamber volume of the PG eyeball after the iris subsidence ratio corresponding to myopia The eyeball is slightly larger. When the eye moves, the iris keratoscope shows a slight tremor around the iris. The iris has no anterior adhesion and posterior adhesion. The degree of peripheral iris depression can be divided into 4 levels: 11: severe iris depression; 22 Grade: mild iris depression; 33: iris flat; 44: iris protrusion, the degree of curvature of the iris can be affected by the blink.

(3) Transillumination defect: the transillumination defect in the peripheral part of the iris develops with the aggravation of pigment spread, and can be identified by two clinical examinations: iris transillumination method: illumination of the sclera with an electric lamp or an optical fiber lamp in a dark room; Another preferred method is to use a low-fold slit lamp to inspect, use a sufficiently bright and narrow slit light strip to enter the eye through the center of the pupil, avoiding the pupil edge, illuminating the lumen of the eye, and passing through the iris defect. It can see the red light reflected from the fundus. The patient needs to perform dark adaptation in the dark room for a period of time before being checked. This is beneficial for finding small defects. The diameter of the pupil is ideal when the diameter is 2~4mm. The pupil is too small. Obtaining sufficient light makes it difficult to obtain a good inspection effect; too large a pupil or drug-induced dilation may make it difficult to find a transillumination defect in the iris accumulation.

Transillumination defects generally have spoke-like fissures around the iris, gradually widening in the middle, occasionally fused, and the defects may be point or round. Occasionally, two adjacent defect connections form a "V" shape, and the apex can be Center, but also to the periphery, the number of defects can gradually increase with time, and sometimes can develop into a discontinuous ring defect, in this case there will generally be 80 to 90 defects, which is related to the number of small bundles of lens suspensory ligament, If the defect is fused, a transillumination ring surrounding the surrounding iris can be seen. Through the adjacent defect, the equator of the lens can be seen. The classification of the transillumination defect: 1 no defect; 2 the defect can be correctly counted; 3 the defect fusion cannot be clear Counting, the defect can be combined with 90°, combined with 270°, etc. Occasionally, because the iris of the brown eye is thicker, even if the pigment spread is obvious, the transillumination defect is not easy to be seen. In some brown eyes, the iris matrix exists. More pigments cover the defects that could have been seen.

3. Pupil: There is an abnormality in pupil size and shape in PDS/PG. Asymmetry of iris can cause asymmetry of pupil, and the most obvious direction of iris transillumination defect has large pupil deformation at the same time. There is hyperplasia.

4. Lens, suspensory ligament: PDS/PG clearly found a complete or incomplete pigment ring in the periphery of the posterior surface of the lens (Fig. 6), usually intermittent, which is produced by pigmentation in the Weigere ligament (vitreous body). In the circular ring between the anterior surface and the posterior capsule of the lens, this pigment is usually not detected by conventional slit lamps in the case of dilated sputum, but it is easy to see with an iris keratoscope in the case of dilation. Pigment aggregation is mostly permanent. It remains unchanged when pigment spreads in other parts are reduced. Therefore, it is considered to be a PDS/PG-specific sign. There is no similar pigment spread in the exfoliation syndrome, and the lens is also in the lens. The pigmented granules are also found in the front central area.

In the fully enlarged eye, through the iris keratoscope, occasionally the scattered ligaments are covered with scattered pigment particles. In this case, the suspensory ligaments are arranged in a small bundle, occasionally showing a V-shape.

5. iris corneal angle: pigment accumulation in the angle of the anterior chamber, especially on the trabecular meshwork, can block the outflow of aqueous humor and cause a chronic increase in intraocular pressure. The angle of the PG patient is usually wide open angle, especially accompanied by The larger eyeball of myopia, the most important manifestation of the corner is the dense brown or black pigment band on the trabecular meshwork and the Schwalbe line. Because of the depression of the surrounding iris, a wide angle of the corner can be seen, often accompanied by rich The iris protrudes in front of the scleral process, and there is normal pigmentation between the irises on the trabecular meshwork. Note that it is different from pigmentation. At first, the pigmentation on the nasal side and the underside of the angle is slightly thickened, usually 0~4. Grade pigmentation, grade 0: no pigment; grade 1: light pigment; grade 2: medium pigment; grade 3: pigment light brown; grade 4: almost black, light brown pigment can be seen in many eyes with age Grades 1 to 2, while the heavier pigments in PDS/PG are grades 3 to 4.

An iris keratoscope with pigment scale is very helpful for grading of trabecular mesh pigments. Occasionally, trabecular mesh pigmentation is quite serious, and the pigment spreads more than the entire trabecular meshwork. In this case, due to excessive pigmentation Causes the trabecular meshwork to swell and protrude slightly into the iris cornea. Most of the PDS/PG patients have a heavier Schwalbe line pigment, and the pigmentation gradually increases from top to bottom. The horizontal meridian can approximate the pigmented part and the non-pigmented part of the Schwalbe line. Separately, occasionally a thin and dark pigmentation band is visible in the lower corner of the room, called the Sampaolesis line. In addition, the number of iris protrusions in the PDS/PG patient's angle increases, and occasionally the iris insertion is slightly irregular. It is suggested that the angle of the corner is deformed, but most of the angles are normal. The ciliary body band can be wide and narrow, but generally wider than normal. The adjustment can increase the iris retraction of PDS/PG, and the lens surface advances before the lens. With a relative increase in atrial pressure, peripheral iridotomy prevents changes in the shape of the iris due to adjustment.

Examination of pigmented glaucoma

Some patients have a family history and can be genetically examined and pedigree analysis.

1. Infrared TV camera: Using infrared TV camera to observe and count the iris transillumination defect, analyze these images, and data the data, which is helpful for follow-up of patients in the pigmented active period.

2. Intraocular pressure tracing: The application of intraocular pressure tracing to PDS/PG patients to determine the outflow of aqueous humor still has a certain effect. According to the fluency of aqueous humor, the future development trend of the disease can be predicted, and the pigment spread can also be understood. The progress of the active period, understanding the changes of the fluency coefficient of the aqueous humor, patients with normal intraocular pressure and abnormal aqueous fluency coefficient often develop into glaucoma, and those who have a smooth outflow of water have less developed into PG.

3. Ultrasound biomicroscopy: high-frequency, high-resolution anterior ultrasound biomicroscopy provides cross-sectional images of the iris morphology around the PDS/PG patient and determines the relationship between the iris and the anterior chamber and lens surface. Ultrasound biomicroscopy has confirmed the presence of contact between the lens iris zonules previously seen through postmortem anatomy.

4. Iris keratoscopy with pigment scale: Boys-Smith et al. invented an iris keratoscope with a pigment scale. With this mirror, a uniform index can be used to measure the degree of pigmentation in the trabecular meshwork.

Diagnosis and diagnosis of pigmented glaucoma

Diagnostic criteria

Mainly based on the signs and intraocular pressure of PDS, glaucoma visual field and optic disc changes, see the mid-circumference iris spoke-like translucent area by transillumination method, the most characteristic, and slit lamp inspection to see the posterior wall of the cornea Krukenberg Fusiform pigmentation, deep anterior chamber, iris posterior depression and hyperpigmentation. After dilatation, the pigmentation of the posterior surface of the lens is near the equator. The keratomileus is a wide angle and the dense pigmentation zone is present on the trabeculae. With iris signs and some other signs, it can be diagnosed as PDS; if accompanied by pathological high intraocular pressure, glaucoma vision and optic disc changes, you can diagnose PG.

Differential diagnosis

1. Iris pigmentation loss: There are no other diseases associated with the iris spoke-shaped transillumination defect in PDS/PG. Patients with congenital glaucoma occasionally have transillumination defects near the attachment of the distal part of the iris, but not spokes. Occasionally, patients with exfoliation syndrome occasionally have pigment dissemination. The position of the transillumination defect is mostly at the edge of the pupil, or the plaque is scattered throughout the iris. The injury to the posterior surface of the iris due to trauma or surgery is irregular. Iridescent pigmentation, due to severe uveitis, patients with posterior iris loss of pigment also have regional plaque loss, but not surrounding spoke-like defects, occasionally in a normal eye can have a marble pattern of transillumination Defect, but it is completely different from the change of PDS/PG.

2. Uveitis: If small pigment particles float in the aqueous humor, they are mistaken for white blood cells and are misdiagnosed as uveitis. To make a correct judgment, it is necessary to notice the typical signs of PDS and lack uveitis. Other symptoms, such as conjunctival hyperemia, KP and post-iris adhesion, pigment loss in the posterior surface of the iris in PDS patients, although phagocytic cells can move forward into the iris matrix, but do not provoke inflammation, herpes zoster keratitis can be Caused by atrophy of fan-shaped iris, herpes simplex keratitis can cause extensive iris atrophy, neither of which has PDS-like iris transillumination defects.

3. Increased trabecular mesh pigmentation: In addition to PDS/PG, abnormal pigmentation can occur in other syndrome eyes, and pigmentation associated with exfoliation syndrome can cause trabecular meshwork to become black. Many such cases In the middle, the pigment is mixed with the exfoliating substance to form an irregular, hemp-like pigment band. A typical Krukenberg shuttle is not developed, and typical capsular exfoliation contributes to correct diagnosis.

Patients with peripheral iris or ciliary cysts occasionally have moderate pigmentation on the trabecular meshwork, but there is no typical Krukenberg shuttle. The diagnosis is made by observing the specific transillumination defect of the peripheral iris PDS. Iris keratomileusis was used to detect sub-irent cysts. In the above two cases, there was no pigmentation on the posterior surface of the lens.

4. Anterior, posterior melanoma: iris, ciliary body or posterior melanoma (if the anterior membrane of the vitreous is ruptured) can be accompanied by pigmentation, pigmented tumor cells or pigmented phagocytic cells can cause anterior and posterior A considerable degree of blackening, but lacks the typical symptoms of PDS/PG: no Krukenberg shuttle, no transillumination defect, easy to detect primary tumor, inflammation of the posterior surface of the iris occasionally has a moderate amount of pigment release, often in the lower corner Cohesive integration of the group, accompanied by the performance of inflammation.

5. Others: PG can sometimes be caused after implantation of the posterior chamber intraocular lens. At this time, the posterior chamber IOL with abnormal position and the iris are in contact for a long time after surgery, causing pigment release.

6. Exfoliation syndrome: The mechanical friction between the peripheral lens and the iris around the pupil in this disease, the iris transillumination defect like pigmented glaucoma, Krukenberg shuttle, trabecular pigmentation and elevated intraocular pressure, but the following conditions are easy Make an identification:

More common in the elderly over 160 years old, rare in the age of 40 years old;

250% of patients were unilateral, gender-free, and refractive error (myopia);

3 Transillumination defects are common in the pupil of the pupil and its surrounding iris, rare in the middle part of the iris, trabecular mesh pigmentation is not as dense as pigmented glaucoma (usually level 2);

4 The most distinguishing feature is the gray-white dandruff-like particles or flakes of the pupillary margin, and the gray pseudo-exfoliating substance on the anterior capsule of the peripheral lens. It has been reported that both diseases can exist simultaneously.

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