iris pigment nevus
Introduction
Introduction to iris pigmentation Nevusofiris is an abnormal aggregation of pigment cells in the shallow stromal layer of the iris, which is clinically common. Iris sputum is a hamartomaous lesion that is a neoplastic mass composed of melanocytes with a benign cytological morphology. basic knowledge The proportion of illness: 0.03%-0.07% Susceptible people: no specific population Mode of infection: non-infectious Complications: glaucoma
Cause
Iris pigmentation cause
(1) Causes of the disease
The cause of iris pigmentation is unknown, mostly congenital. Caucasians are more common than colored people. Patients with neurofibromatosis are often accompanied by multiple iris fistulas.
(two) pathogenesis
Aggregation of abnormal pigment cells in the shallow stromal layer of the iris is a neoplastic mass composed of benign cytological melanocytes. Pigmented nevus is generally stable and healthy, with no obvious growth tendency. Occasionally, malignant changes can occur.
Prevention
Iris pigmentation prevention
The cause of this disease may be related to genetics, nutrition during pregnancy, environmental factors, and can not be prevented for hereditary causes, but attention should be paid to the health care during pregnancy, including maintaining a good pregnancy mentality and diet, and maintaining adequate vitamin intake. Into, has a certain effect on the prevention of this disease.
Complication
Iris pigmented nevus complications Complications glaucoma
Some iris pigmented nevus can be associated with glaucoma.
Symptom
Iris pigmented nevus symptoms common symptoms iris inflammation iris heterochromia pupil deformation pupil margin valgus
Generally asymptomatic, the lower iris, near the pupillary margin area, is clinically divided into two types: focal iris and diffuse iris.
1. Focal iris sputum: the iris near the pupil edge or the middle part, the peripheral part, occasionally the corner of the corner, the size is different, the boundary is clear, the slight uplift, generally brownish black or dark black, the pigment variation is large, The typical iris is avascular, and most of the iris is stable and does not develop. Very few can affect adjacent tissues. The iris of the proximal pupil can cause pupillary deformation, and the pigmentation of the pupillary margin is valgus, but it does not indicate that the iris is malignant.
2. Diffuse iris sputum: relatively flat, often involving the whole or part of the iris, some is a clinical manifestation of iris syndrome (Cogan-Reese syndrome), Cogan-Reese syndrome and primary iris atrophy, Chandler synthesis The syndrome is attributed to iris corneal endothelial syndrome (ICE). The clinical manifestations are monocular glaucoma, corneal edema, iris heterochromia, rough iris matrix, multiple nodules in the iris, pupillary deformation, pupillary pigment valgus. The anterior adhesion of the iris, etc., its pathological mechanism is idiopathic corneal endothelial hyperplasia with secondary iridoinopathy.
It is easier to determine the diagnosis of iris sputum by slit lamp microscopy.
Examine
Iris pigmentation examination
Histopathological findings: the pigmented nevi is mostly located in the shallow stromal layer of the iris, which can be slightly elevated in the anterior chamber. Most of the iris pigmented nevus is composed of well-differentiated small spindle-shaped sputum cells, or doped with a small round sputum cell, intracellular. Containing different amounts of melanin particles, this form of pigment is called spindle-shaped cytochrome, a small number of iris pigmented nevus is large, dark black, which is mainly composed of large round melanocytes, which are rich in melanin particles. The pigmented sputum composed of such cells is also called melanoma or large cell-like sputum. The fusiform sputum cells usually adhere closely and are not easy to fall off, but the large round melanocytes adhere loosely and are prone to spontaneous necrosis. , shedding or involving the iris corneal keratosis, leading to secondary glaucoma.
Ultrasound biomicroscopy: It is helpful to distinguish from iris melanoma. The iris UBM is characterized by abnormal iris elevation, clear but irregular boundaries, uniform internal reflection, and some cases have a umbilical change or crater. Such changes, the posterior boundary of the lesion is not clear, and there may be mild acoustic attenuation.
Diagnosis
Diagnosis and identification of iris pigmented nevus
The iris needs to be differentiated from iris melanoma and ocular melanocytosis.
1. Iris melanoma: mainly by regular observation, UBM examination helps to distinguish from iris melanoma. The iris echo is stronger than iris melanoma, the edge is clear and sharp, and the lesion is less limited. When the lesion diameter exceeds 3mm, the thickness exceeds 1mm. Or with lens opacity, secondary glaucoma, iris neovascularization, ciliary body involvement and anterior segment pigmentation, should be highly alert to iris melanoma.
2. Ocular melanocyte hyperplasia: It is a melanin deposition disease involving multiple tissues of the sclera, conjunctiva, cornea, tarsal plate, iris, iris corneal angle, choroid and other eyes. In some cases, malignant transformation can occur.
