idiopathic macular hole
Introduction
Introduction to idiopathic macular hole Idiopathic macular holes are the most common primary lesions in the eye, such as refractive errors, ocular trauma and other vitreoretinal lesions, which are most common in the macular hole. basic knowledge The proportion of illness: the incidence rate is about 0.003%-0.005% Susceptible people: no specific population Mode of infection: non-infectious Complications: retinal detachment
Cause
Idiopathic macular hole
(1) Causes of the disease
There is no obvious detectable cause of idiopathic macular hole, and the macular hole that appears to exclude the disease of the fundus itself accounts for the majority of the macular hole. In such patients, the incidence of cardiovascular disease is high, so the incidence of macular hole is considered May be associated with choroidal ischemia, and found in patients with estrogen or hysterectomy, the incidence of macular hole is high, so it is believed that sex hormones may be related to the pathogenesis of macular hole. In recent years, it has been emphasized that the vitreous macula on the vitreous surface is pulled. The importance of the macular hole is believed to be the concentration and coagulation of the vitreous body, and the traction in the tangential direction of the fovea of the macula plays an important role in the formation of the macular hole.
(two) pathogenesis
1. The role of the front and back of the vitreous and the tangential direction
From the 1970s to the early 1980s, many scholars began to notice that the formation of macular hole is related to the abnormality of the vitreoretinal in the macular area. It is believed that the disease is closely related to the traction of the vitreous. Under normal physiological conditions, the vitreous cortex is closely related to the macular area. Connected, when the eye moves, the vitreous movement draws the macula. In the pathological condition, the vitreous body concentrates. When contracted, the traction on the macula is more obvious. Long-term traction leads to retinal edema, degeneration, and finally a hole. At that time, it was thought that The anterior and posterior traction of the vitreous is the main cause of IMH formation. Posterior vitreous detachment (PVD) plays an important role in the formation of IMH. Many scholars have supported this theory for a long time.
However, in 1988, Gass et al. found that only 12% of patients had PVD in the analysis of large sample IMH, suggesting that the anterior and posterior traction of the vitreous to the retina is not the main reason for the formation of IMH. On the contrary, the occurrence of PVD has prevented it to some extent. With the further development of IMH, Gass used biomicroscopy and fundus fluorescein angiography to observe a group of patients with different symptoms and obvious symptoms for a long time. It was pointed out that the posterior vitreous cortex of the foveal surface of the macula was shrunk and tangentially pulled. An important cause of macular hole formation, and according to the observation results IMH is divided into 4 stages, Guyer and Green believe that the vitreous to the macular tangential traction caused macular hole, there may be three mechanisms: intraocular fluid flow, remodeling of vitreous cortical cells And the cell membrane component forms a pull on the inner surface of the vitreous; the proliferation of cell components along the inner surface of the vitreous cortex contributes to the formation of the traction; the cell aggregation in the vitreous cortex and the rearrangement of the fibers, the contraction causes the traction, and later scholars observe Go to the "tangential pulling" phenomenon and find that in addition to the vitreous cortex, the visual network Surface hyperplasia is also involved in the process.
With the deepening of the understanding of IMH, more and more clinical observations have shown that the anterior and posterior traction of the posterior vitreous detachment also plays a role in the development of IMH. Some scholars use OCT, ultrasound and HRT to the IMH vitreoretinal interface. In a detailed study, Kim et al. observed the phase II IMH, and considered that in the process of the stage II hole progressing to the stage III or IV stage, in addition to the simple vitrectomy, the other oblique and anterior and posterior traction forces were also It plays an important role. Chan et al. used OCT to observe the situation of IMH in the contralateral eye. It was found that there was a serious vitreoretinal interface abnormality in the contralateral eye and eventually a full-thickness macular hole. These studies also demonstrated the role of vitreous traction in the formation of the hole. John's observation of the macular vitreous interface using high-resolution ultrasound showed that the localized vitreous detachment before the macula was the initiator of IMH formation. It is speculated that the posterior vitreous detachment around the fovea of the macula can exert a forward force on the fovea, eye movement. A local dynamic pull can be applied to the fovea to cause the fovea to split, and Bishop studied III, IV using RTA. The morphology of IMH suggests that the forward pull force of the posterior cortical pull is the initiating factor of IMH formation, while the tangential pull force plays an important role in the expansion of the hiatus. Therefore, from the current research results, for IMH In terms of occurrence and development, both the anterior and posterior traction and tangential traction of the vitreous body work.
2. The role of the inner limiting membrane
In the ongoing research, there are still some problems that cannot be fully explained by Gass' theory on the pathogenesis of IMH. These phenomena suggest that in addition to the role of vitreous, other factors may play an important role in the occurrence and development of IMH, IMH. The incidence of macular epiretinal membrane was more than 65%. The incidence of macular anterior membrane in the IV stage was significantly higher than that in the third stage (24.6%). It was considered that the macular anterior membrane was secondary to the formation of the hole. The further expansion has an effect. After the combined removal of the macular anterior membrane, the healing rate of the hole is higher than that of the vitrectomy alone. The retinal inner membrane is removed along the macular hole, and the closure rate after IMH is 95%. ~100%, therefore, in the development of IMH, in addition to the traction of the vitreous to the retina, the epiretinal membrane of the retina also participates in the development of IMH, its role includes at least:
(1) Serves as a scaffold for hyperplasia of the retina surface.
(2) The inherent centrifugal tension of the inner limiting membrane itself participates in the expansion process of the slit.
3. The role of intraocular pressure
The retinal and inner limiting membrane tissues are elastic tissues, which are easily affected by pressure. In order to clarify the influence of intraocular pressure on the formation and development of IMH, animal experiments have been carried out using monkey eyes, and the neuroepithelial layer of the macular area of the monkey eye was cut by YAG laser. The macular hole model was made, and then the intraocular pressure was increased to 40-50 mmHg. After 1 hour per day and the intraocular pressure increased for 2 months, the macular hole was significantly enlarged compared with the control group. It is speculated that intraocular pressure may also participate in the formation and development of IMH, but it remains to be seen. Further confirmed.
Prevention
Idiopathic macular hole prevention
There is no effective preventive measure for this disease. Early detection and early diagnosis are the key to the prevention and treatment of this disease.
Complication
Idiopathic macular hole complications Complications
Cystic edema around the macular hole, the formation of the anterior membrane of the retina, but there is little chance of retinal detachment.
Symptom
Idiopathic macular hole symptoms Common symptoms Lens opacity visual distortion Macular cystic edema
Symptom
The onset of the disease is concealed, the progress of the disease is slow, and sometimes it is discovered when the other eye is covered. It can be asymptomatic at an early stage. As the disease progresses, the clinical manifestations of different phases are different. Common symptoms include decreased vision and visual distortion. Etc., the visual acuity often falls to 0.05 to 0.5, with an average of 0.1. The Amsler square table can be used to detect the visual distortion and the central dark spot.
Reasons for the impact of the function include the following:
(1) There are no retinal photoreceptors at the macular hole.
(2) Shallow detachment of the retina around the macular hole.
(3) Cystic edema around the macular hole.
(4) Apoptosis of photoreceptor cells around the macular hole.
2. Fundus examination
The ocular changes in idiopathic macular holes are mainly in the macula of the fundus. Most cases are accompanied by incomplete or complete posterior detachment of the vitreous. In addition, due to the majority of the elderly, there are often varying degrees of lens opacity or lens nucleus hardening.
The fundus manifestations of IMH in different periods have their own characteristics. When the early holes are not formed, only the yellow spots and yellow rings in the macular area are seen. Sometimes the vitreous traction and the preretinal membrane are present. After the disease progresses, the macular hole is formed. The base is dark red under the ophthalmoscope. The circular holes can also be half-moon or horseshoe-shaped, with different diameters, but most of them are 1/4~1/2PD. If there is cystic edema around the hole, it can be expressed as a halo in the hole edge and after the vitreous in the late stage. Get detached or accompanied by a free cover.
Examine
Idiopathic macular hole examination
Fundus fluorescein angiography
Fundus fluorescein angiography clearly shows the morphology of the capillary ring in the macular area, the deformation of the small blood vessels that have developed lesions, the distortion phenomenon, and the abnormally strong fluorescence from the lesion area, fluorescent masking or spotting, irregular fluorescence infiltration leak.
In the early stage of idiopathic macular hole, the fundus showed only a shallow fovea, yellow spots in the macular area, and no pigment epithelial changes. At this time, there was no obvious abnormal change in fluorescein angiography. If the lesion progresses further, it can be found due to RPE damage. The window looks transparent, such as the hole around the hole is clearly detached, and the annular weak fluorescent region outside the central strong fluorescence is also visible.
2. Optical coherence tomography
OCT examination of the idiopathic macular hole is very intuitive, and can provide the characteristics of the macular hole and its deep retinal section, analyze the location, shape, size, retina and vitreous of the macular hole to determine the presence of cystoid edema. The macular area is shallowly detached and the faint and transparent macular anterior membrane can clearly identify the full-thickness, lamellar or pseudo-macular hole. For monocular IMH patients, OCT can also be used to evaluate the risk of MH formation in the contralateral eye. In one study, 21% of patients had vitreoma abnormalities in the lateral eye.
The stage I macular hole showed that the fovea of the normal macular disappeared, and a low-reflection area appeared below it. There was no rupture in the inner layer of the macula. Vitreous traction was observed in the foveal area. The OCT image of the stage IMH showed that the inner surface of the retina was ruptured with small. The full-thickness retinal tissue is missing. The stage III macular hole shows a well-defined foveal full-thickness retinal defect. The marginal thickness of the retinal neuroepithelial layer is increased, accompanied by a decrease in light reflex and edema in the retina. The high echo of the cap, the stage IV shows the full-thickness macular hole with the vitreous completely detached from the macula and the optic disc. The appearance and application of OCT further confirms and perfects the staging of the IMH by Gass, and has important guiding significance for judging the surgical indication.
3. Function check
As a psychophysical examination method, visual field examination can accurately reflect the early changes of macular diseases by measuring the macular threshold. The automatic perimetry can be used to analyze the regional light sensitivity according to the extent of macular lesions.
Early idiopathic macular holes may have no visual field abnormalities. Most of the late stage have different degrees of light sensitivity decline, which may be related to poor visual acuity, retinal edema, photoreceptor arrangement disorder, macular anterior membrane occlusion, vascular leakage, etc., using light sensitivity. The changes and the fluctuation of the light threshold can be used to evaluate the visual function of the progression of the idiopathic macular hole and the surgical effect.
Visual electrophysiological examinations commonly used to determine macular function include clear electroretinogram, scotopic red light and bright red electroretinogram, scintillation electroretinogram, local macular electroretinogram, multifocal electroretinogram Multifocal electroretinogram (mERG), visual evoked potential, etc., in which mERG examination has the characteristics of objective, accurate, localized and quantitative, which can more accurately, sensitively and quickly determine the visual function within 23° of the posterior pole retina. The macular hole has little effect on the electrical activity of the whole retina. The early visual electrophysiological examination generally has no obvious abnormality. In the late stage, the amplitude of the multi-focal ERG is more obvious, and the change of the multi-focal ERG is more obvious. The foveal response is significantly reduced or disappeared. As an objective and sensitive indicator for evaluating visual function, it is of great significance for analyzing the progress of the disease and the effect of surgery.
Diagnosis
Diagnosis and diagnosis of idiopathic macular hole
diagnosis
After detailed fundus examination, especially under the slit lamp, the diagnosis can be established. The occurrence of OCT is the diagnosis and differential diagnosis of macular hole, which provides a more objective and accurate basis and becomes the diagnosis and differentiation of macular hole. The gold standard for diagnosis.
Differential diagnosis
1. Macular full-thickness
The edge of the yellow hole is sharp, and the light tangential line under the slit lamp under the slit lamp is interrupted or misplaced. The sputum patient can observe the light and can detect the light interruption. The hole has a halo or localized retinal detachment. The bottom of the hole can have yellow and white dots. The patient can see a semi-transparent cover film that adheres to the locally thickened posterior vitreous interface. The OCT image shows a full-thickness defect (with or without lid) of the retinal neuroepithelial band in the macular area.
2. Macular plate hole
The edge of the hole is clear. Under the slit lamp, the light tangent becomes thinner under the front mirror, but there is no interruption or dislocation. The patient does not feel the light is interrupted, and there is no halo around the hole. Only the bright reflection is reflected in the OCT image. Part of the retinal neuroepithelial light band in the macular area.
3. Macular false hole
The formation of the anterior membrane of the retina can thicken the retina and accumulate to the center. It is like a macular hole in the ophthalmoscope or fundus, but it shows a steep shape in the OCT image, and the retinal neuroepithelial light band is intact.
4. Macular cystosis
When the small cyst is ruptured to form a large cyst, there may be a change similar to the macular hole under the ophthalmoscope, but the OCT image clearly shows the complete retinal tissue and cyst formation.
