Primary chronic angle-closure glaucoma

Introduction to primary chronic angle-closure glaucoma Primary chronic angle-angle glaucoma (chronicprimary angle-closureglaucoma) is a type of reason that is not fully understood, resulting in sudden or progressive closure of the angle of the anterior chamber. The surrounding iris blocks the trabecular meshwork and blocks the drainage of the aqueous humor. A type of glaucoma that is elevated or progressively elevated. basic knowledge The proportion of illness: 0.003% Susceptible people: no special people Mode of infection: non-infectious Complications: optic atrophy

The cause of primary chronic angle-closure glaucoma

(1) Causes of the disease

1. Anatomical features of primary angle-closure glaucoma: In the normal population, the anatomical parameters of the eye are normally distributed, and the parameters have a strict proportional relationship, for example, a person with a long axis Often, the radius of curvature of the cornea is large, the anterior chamber is deep, and the lens is relatively flat. The above parameters have a strict proportional relationship. In fact, it is a compensation mechanism, a large radius of curvature of the cornea, a deeper anterior chamber depth and The flat lens compensates for the myopia that may be caused by the longer eye axis. On the contrary, for a person with a shorter axis of the eye, in order to compensate for the hyperopia that may be caused by the short axis of the eye, his radius of curvature of the cornea is relatively small, and the anterior chamber is relatively small. Normal people are shallow, and the radius of curvature of the lens is small. If this compensation mechanism is not complete, hyperopia or myopia may occur.

For patients with primary angle-closure glaucoma, their anatomical features are characterized by shorter axial length, shallow anterior chamber, small radius of curvature of the cornea, small radius of curvature of the lens, thick lens, and relative position of the lens. So many of them are farsighted.

(1) anterior chamber depth: In the above anatomical features, the anterior chamber depth is an extremely important anatomical feature, which indirectly reflects the position of the lens in the eye, that is, it reflects the anterior surface of the lens and the attachment point of the iris root. The relative position of the anterior chamber of patients with primary angle-closure glaucoma was 1.0 mm shallower than that of normal subjects. The factors due to the increase of lens thickness accounted for 35% (0.35 mm), and the factors due to the advancement of the lens position accounted for 65. % (0.65mm).

The depth of the anterior chamber is not static. The depth of the anterior chamber may change at different times, in different states and at different times. This change can reach 0.2 mm. The depth of the anterior chamber of the acute angle-closure glaucoma is less than that during the day. When it is less than 2.5 mm, the area of the anterior surface of the lens contacted by the pupil sphincter is in front of the attachment point of the iris root, which may increase the occurrence of pupillary block.

(2) lens position and lens thickness: the position of the lens and the thickness of the lens are related to the development of the whole eyeball. The lens with large thickness tends to be more advanced. The thickness of the lens and the position of the lens are constantly changing during the lifetime, and the thickness of the lens can be increased by 0.75. ~1.1mm, the position of the lens can be moved forward by 0.4 to 0.6mm, and the ratio of lens thickness/axial length of the angle-closure glaucoma patients is more significant with age.

(3) radius of curvature of the anterior lens: with the increase of the thickness of the lens, the radius of curvature of the anterior lens gradually becomes smaller. The average radius of curvature of the lens in patients with closed angle glaucoma is 7.96 mm, and the radius of curvature of the anterior lens is 7.50 to 15.38 mm. The radius of curvature of the anterior cornea is 7.13 to 8.54 mm, and the radius of curvature of the anterior lens is larger than the radius of curvature of the anterior cornea.

(4) Corner structure: The width of the angle of the corner and the depth of the corner crypt are closely related to the occurrence of angle-closure glaucoma. The width of the angle depends on the degree of iris bulging, the length and thickness of the iris root, and the attachment point of the iris root. In addition, the width of the angle depends on the area and extent of the iris contacted by the lens. The depth of the crypt depends on the distance between the scleral process and the root of the iris and the ciliary body. The iris cornea angle of the myopic eye is generally broad. The angle of the crypt is deeper, while the angle of the angle-closure glaucoma patient is narrower and shallower, especially the upper and lower quadrants are narrower and shallower. This angle structure provides this type of glaucoma. Another anatomical basis for the corner closure.

2. Predisposing factors for the closure of the angle: Since Schenborg found that the occurrence of angle-closure glaucoma is related to dramatic changes in mood, many scholars have published reports in this regard. Shily et al. used a comparative study of psychology to prove the angle-closure glaucoma. The occurrence is related to emotions. For psychosomatic diseases, such patients may have certain personality physiques. They have poor adaptability to rapid changes in the surrounding environment, often causing severe emotional changes, and may be caused by autonomic nerves or possibly through neurohumoral pathways. Physiological and even pathological changes, some people found that the angle-type glaucoma group strong A and partial A personality composition ratio than the normal control group, the analysis that closed-angle glaucoma is a typical psychiatric disease, autonomic nerve function in patients with angle-closure glaucoma Unbalanced, sympathetic tone is high, parasympathetic tone is low, and the pupillary cycle time of the angle-closure glaucoma group is significantly longer than that of the normal control group and is associated with systemic parasympathetic neuropathy, and the normal control group with anterior chamber depth exceeding 2.5 mm. In contrast, closed-angle glaucoma iris autonomic function is weakened, especially Parasympathetic blunted, and anterior chamber depth of less than 2.5mm and less than normal shallow anterior chamber compared two groups of autonomic function decreased.

Some studies have found prostaglandins, bradykinin, plasma atrial natriuretic receptors in the iris and ciliary body, and found that the occurrence of angle-closure glaucoma may be related to them, and patients with angle-closure glaucoma The plasma atrial natriuretic peptide level was significantly higher than that of the normal control group, suggesting that the change of plasma atrial natriuretic peptide level is the result of local eye stress protection response. Is there a certain relationship between this phenomenon and closed angle glaucoma? Further research is needed.

According to the above research results, it can be seen that no matter which of the above factors, which path will eventually affect the anterior segment vasomotor dysfunction, telangiectasia, ciliary body edema, increased aqueous humor, increased posterior pressure, iris bulging The result is bound to cause the angle of the corner to close in an eye with a narrow angle of the corner, triggering the occurrence of angle-closure glaucoma.

(two) pathogenesis

The relative position of the lens is moved forward to a certain extent, so that the anterior surface of the lens in the region of the pupil sphincter exceeds the position of the attachment point of the iris root, which may cause the component of the pupil sphincter and the pupil to open the muscle to increase in the direction of the lens, thereby causing the posterior aqueous humor to The resistance of the pupil to the anterior chamber increases, which is often referred to as relative pupillary block.

When the pupillary block occurs, the resistance of the posterior chamber water to the front chamber through the pupil area increases, and the following can occur:

1 The pressure in the posterior chamber increases, which overcomes the pupillary block force, and the aqueous humor enters the anterior chamber through the pupil area;

2 The posterior chamber pressure increased but the pupillary block could not be overcome. The posterior chamber pressure was greater than the anterior chamber pressure, causing the surrounding iris to bulge forward, but the degree of peripheral iris bulging did not reach the extent that the angle of the corner was closed, and the angle was still open;

3 Peripheral iris bulging has led to the closure of the angle of the anterior chamber, and the aqueous humor discharges the obstacle from the anterior chamber angle.

Corner closures can also take many forms:

1 Suddenly, all the corners of the room are closed, causing the eye pressure to rise sharply;

2 sudden, but some of the angle of the corner is closed, which may cause moderate or elevated intraocular pressure;

The 3 angles gradually closed gradually, causing the chronic angle to close and the intraocular pressure to gradually increase.

The characteristics of the lens, the relaxation of the suspensory ligament and the tissue characteristics of the iris may be closely related to the difference in the form of the angle of the angle of the anterior chamber. In addition, there may be other factors that are still unclear to determine the form of the angle closure of the angle-closure glaucoma. .

1. Stability of the lens: The lens generally maintains a relatively stable state, and the relaxation of the lens suspensory ligament can lead to a decrease in the stability of the lens position, resulting in a sudden advancement of the lens, especially in the reading or prone, causing the lens to move forward, which increases the pupil block. , resulting in acute closure of the angle of the anterior chamber, in some patients after the use of miotic agents, ciliary muscle contraction, increased relaxation of the lens suspensory ligament and induced acute closure of the angle of the anterior chamber, and in the exfoliation syndrome due to the pathological changes of the suspensory ligament can also occur before the lens Move to increase pupillary block.

2. Iris tissue structure: the structure of the iris, especially the thickness, elasticity, tension and angle of the iris are closely related. The thinner, less elastic iris is thicker and the elastic is more susceptible to the posterior chamber pressure. Bulging, Asians, black iris tissue is thicker, tension is greater, so most of the angle closure is a chronic progressive closure, which may be one of the reasons.

Peripheral iris annular folds and angle closure are also closely related. In some patients with short iris roots and narrow angles, when the pupils are scattered, the corners can be blocked by these folds, and in other eyes, the annular folds are When the pupil is opened, it is far away from the angle of the anterior chamber. If the pupillary block has been lifted (after the week), the angle of the anterior chamber will be widened.

In short, in the presence of pupillary block, the degree of peripheral iris bulging is closely related to the elasticity and tension of the iris. The contraction of the pupil increases the tension of the iris, which can flatten the surrounding iris folds and relieve the angle of the angle, but only the pupil The blockage is present and the iris is still in a bulging state.

3. Pupil opening the large muscle: The pupil opening muscle is located behind the pupil sphincter and is connected by the cell process. When the pupil opening muscle is actively contracted, the open muscle contraction speed is faster than the surface iris tissue, and the result can pull the pupil sphincter. In the direction of the lens, the shallower eye in the central anterior chamber, because the front of the lens in the anterior position can simultaneously increase the force component of the pupil opening muscle in the direction of the lens, the result is that the degree of pupil block is increased under the above two factors.

4. Pupil sphincter: When the pupil sphincter is maximally contracted, the relative pupillary block is increased, but the force component in the direction of the lens produced by the pupil sphincter is the smallest. As the pupil expands, the force component of the sphincter in the direction of the lens Then increase, at the maximum state of the pupil, the contraction of the pupil sphincter exacerbates the pupillary block, especially when the use of a miotic agent against the dilated state caused by the mydriatic agent may cause the corner to close. It occurs when the mydriatic and miotic agents are used at the same time and the pupils are kept at a medium size to block the pupils to the strongest degree. At the same time, the peripheral iris is also likely to accumulate and block the corners.

Primary chronic angle-closure glaucoma prevention

The disease belongs to a type of glaucoma caused by the acute closure of the angle of the sensitive person due to certain physical and mental and environmental factors, which leads to an increase in intraocular pressure. The basic cause is related to the state of the angle of the anterior chamber. The mood is comfortable, and attention to the temperament may have some pathology. Preventive effect.

Primary chronic angle-closure glaucoma complications Complications optic atrophy

The angle of the corner is closed, and the optic nerve is atrophied.

Primary chronic angle-closure glaucoma symptoms Common symptoms Rainbow edema head faint optic atrophy high intraocular pressure

1. History: About 2/3 of the patients with chronic angle-closure glaucoma have a history of recurrent episodes, with more or less eye discomfort, seizure vision and rainbow vision in some cases, and some cases have dizziness or Headache, this kind of seizure is more common in winter than in summer, emotional stress, excessive fatigue, long time reading or close work, watching movies, insomnia and chess are often involved in seizures, some women show before or after menstrual period or menstrual period Regular onset.

All patients believe that after sleep and full body weight, the intraocular pressure can return to normal, the symptoms disappear, and even the advanced cases have the same feeling, but the symptoms can not be completely relieved, the longer the course of the disease, the smaller the effect of sleep on treatment, very few patients complained about the morning Symptoms, in the early stages of the disease, elevated intraocular pressure and its accompanying symptoms, only once in a few months, if the disease continues, the interval is getting shorter and shorter, the attack time is getting longer, some cases, until Almost every night, you need to go to the hospital.

Less than one-third of patients with chronic angle-closure glaucoma have no symptoms, and like the primary open-angle glaucoma, occasionally covering the healthy eye, they have found that the eye is blind or has serious visual impairment. If the iris corneal angle is not examined in detail, it is often misdiagnosed as primary open angle glaucoma.

2. External eye and fundus conditions: Usually, the eyeball is not congested under high intraocular pressure. When the intraocular pressure is elevated, the cornea is generally transparent, showing more or less epithelial edema. The level of intraocular pressure is usually slightly dilated in the state of high intraocular pressure. The pupillary light reflection is mostly normal, and a few cases are dull.

Fundus examination showed that the early optic disc was completely normal. When it reached the development stage or the late stage, it showed the degree of optic disc depression and optic atrophy. The change of optic disc depends on the stage of disease development.

Examination of primary chronic angle-closure glaucoma

No special laboratory tests are required.

1. Corner examination and evaluation: The most important diagnosis of primary angle-closure glaucoma is the examination and evaluation of the angle of the corner, including the inspection and evaluation of the angle of the corner and the degree of closure of the angle of the corner. It can also be examined with a anterior segment ultrasound biomicroscope using a gonioscopic mirror.

(1) gonioscopic examination: as a primary angle-closure glaucoma angle inspection ideal angle mirror is a four-sided depression type corner mirror, such as Zeiss four-sided indirect angle mirror, the inspection should include static inspection and dynamic inspection Two contents, static inspection is to evaluate the width of the corner in the natural state, so the human interference should be reduced to the minimum when checking; dynamic inspection, using the corner mirror indentation method, through the corneal depression The water flows to the corner of the corner to be observed, which reduces the degree of iris swelling in the area, increases the visibility of the angle of the corner, and evaluates the angle of the corner, including the depth of the corner, the width of the iris, the location of the attachment point of the iris, the angle of closure of the angle, and other pathologies. Change, such as trabecular mesh pigment level.

In order to better judge whether the corner is functionally closed, it is necessary to perform a corner mirror inspection in a darkroom environment. This inspection can be combined with the results of the darkroom test, or it can be separately performed in the dark room for comparison between the bright light and the dark light. In the dark light, the angle of light is generally changed to the minimum square light, avoiding the irradiation of the pupil area, causing the pupil to shrink. Because this kind of inspection is difficult to avoid artificial interference factors, it cannot be overly dependent on the inspection result, and should be combined with the dark room. The change of intraocular pressure before and after the test made a more reasonable judgment.

For the grading of the corner, the currently accepted and commonly used system is the Shaffer classification system. The description and recording of the corner of the Spaeth classification are more detailed, including the depth of the corner, the width, and the location of the surrounding iris.

(2) Ultrasound biomicroscopy: High-frequency ultrasound biomicroscopy can be used for non-invasive inspection of the natural angle and the angle of the chamber in the darkroom state, and can be used to quantitatively describe the angle structure. This technique can be used in the corner inspection. The human disturbance factor is greatly reduced, real-time image recording and quantitative measurement of the angle of the corner and the surrounding iris in the natural state, and the darkroom corner inspection can also be performed indoors under low light, and the evaluation of the corner function is closed and can be closed. The degree provides a more reliable means, and because the technique can simultaneously record the ciliary body and posterior chamber images in real time, the comprehensive angle analysis can analyze the possible mechanism of the corner closure.

2. Quantitative measurement of anterior chamber morphology and anterior segment anatomy: Slit lamp microscope photogrammetry and slit lamp microscope anterior segment image processing method can make overall quantitative measurement of anterior chamber morphology, including anterior chamber volume, pupillary block force, peripheral The degree of iris bulging, the depth of the anterior chamber of different parts, etc., ultrasound biomicroscopy can be used to qualitatively and quantitatively measure the anatomical features of the anterior segment of the eye. In addition to the above indicators, the volume of the posterior chamber, the thickness of the surrounding iris, and the ciliary shape Quantitative measurements were made on indicators such as body position, corner entrance, and iris root attachment points.

3. Closed-angle glaucoma challenge test: Some scholars have advocated the use of an excitation test designed for angle-closure glaucoma to screen for the possibility of angle-closure glaucoma, but because of the high false positive and false negatives in this type of challenge test. As a result, especially in the case of a negative result, the angle-closure glaucoma cannot be ruled out. The strong positive test results and the combination of darkroom gonioscopic examination have certain judgmental significance. Currently, the commonly used excitation tests have the following types:

(1) Darkroom test: Dark light is a malignant stimulus for some glaucoma. As early as 1914 to 1928, Seidel proposed darkroom test as one of the methods for diagnosing glaucoma. This method is still used clinically. It is safer, does not require special equipment, and the method is simple and easy. Before the test, various anti-glaucoma drugs should be stopped for 48 hours, so that the inspected person stays in the absolute dark room (or covered eyes) for 1 to 2 hours, and must remain awake. If the pupil will shrink in sleep, affecting the test results, young people's pupillary response is more flexible, generally 1h, the elderly pupil is relatively small, and how many are in a straight state, the pupil is not easy to dilute, generally advocate 2h test is appropriate, The positive rate of the 2h test was higher than that of 1h. For some highly suspicious young people, there was also a 2h test to aid diagnosis.

After the test, the intraocular pressure should be measured rapidly under dark light (or red light). It is generally considered that the intraocular pressure is increased by 1.07 kPa (8 mmHg), and the increase of 0.8 kPa (6 mmHg) is also considered as a positive standard. The low standard disagrees that the darkroom test is due to dilated pupils, and the iris is blocked by the angle of the eye to cause an increase in intraocular pressure. When the intraocular pressure is increased by 6-8 mmHg, it is difficult to find the visible changes in the angle of the anterior chamber. Such a positive result is lacking. The exact diagnostic value, patients with positive darkroom test, not only observe the difference in intraocular pressure before and after the comparison test, but also observe the change of the angle of the anterior chamber, especially the narrowest slit light to observe to avoid affecting the observation result. The pressure drop 0.5% to 1% pilocarpine, rapid control of intraocular pressure, the positive rate of the angle-closure glaucoma stimulation test, the author's report has some differences, the differences are mainly related to the selection of positive criteria and the course of the subject Relevant, certainly diagnosed as obvious angle-closure glaucoma, the positive rate of this test and the absolute value of the increase in intraocular pressure, have significantly improved.

There is no unified opinion on the mechanism of intraocular pressure increase caused by darkroom test. There are two different mechanisms in darkroom test. One is normal eye, primary open angle glaucoma and angle-closure glaucoma with miotic agent. The increase in mild intraocular pressure due to darkroom testing may not be due to occlusion of the angle of the anterior chamber. Neurovascular changes appear to be the most likely explanation; the other is the prominent eye caused by angle-closure glaucoma without the use of a miotic agent. The increase in pressure is due to the enlargement of the pupil and the obstruction of the angle at the end of the iris.

(2) Reading test: The reading test is first advocated by Gradle for the diagnosis of early glaucoma. The test method is to measure the intraocular pressure before the test, and then the patient is at the nearest distance, read the 5th font book 1h, the presbyopic patient can wear the mirror to read, according to According to Gradle, the intraocular pressure increased by 0.66 to 1.35 kPa (10 to 15 mmHg), and the positive rate of reading tests according to this standard was relatively low.

There are also various inferences about the mechanism by which reading causes elevated intraocular pressure. The role of reading tests is composed of many complex functions, including regulation, convergence, pupil contraction, eyeball rotation, and their effect on intraocular pressure is due to age, regulation. Force and distance vary with font size. For a long time, reading causes a significant increase in intraocular pressure in a small number of patients. Usually seen in a narrow angle, the mechanism of elevated intraocular pressure may be related to abnormal shape of the ciliary body. When the ciliary body is in the active state, the root of the iris is pushed toward the trabecular bone, and the intraocular pressure increases during the reading test, suggesting that during the adjustment, the ciliary body rotates around the sclera, and the iris root is attached to the trabeculae forward, thereby causing the eye. The pressure rises.

(3) Prone test: Hyams et al. first advocated the use of prone test as a method for diagnosing early glaucoma. The test method is that the patient is lying on the bed facing down, the forehead is resting on the back of the hand or the stable pillow, and the eye is closed for 1 h in the awake state. If the intraocular pressure rises 1.064 kPa (8 mmHg) after prone, it is considered positive.

Some people had a prone test on 132 normal eyes and 146 angle-closure glaucoma. After the test, the normal eye pressure increased by 0.22 kPa (2.58 mmHg), the standard deviation was 2.63 mmHg, and the average value was +2 standard deviations = 1.04 kPa. (7.84mmHg), with 1.064kPa (8mmHg) as the positive standard, 2 eyes (1.5%) in the control group, and 52 eyes (35.6%) in the angle-closure glaucoma.

The prone test causes the increase of intraocular pressure. In the prone test, the position of the lens may be moved forward on the iris, which may aggravate the effect of pupillary block, and it is proposed that the depth of the anterior chamber before and after the test can be directly provided. Evidence, the prone test often shows an increase in intraocular pressure of 1.064 kPa (8 mmHg) for most angle-closure glaucoma, and 1.064 kPa (8 mmHg) for non-closed glaucoma, so this test is effective for the diagnosis of angle-closure glaucoma. One of the methods.

(4) Dilated test: The dilated test can be used as a method for diagnosing early glaucoma, but it should not be used as a routine test because it can cause an increase in acute intraocular pressure in angle-closure glaucoma, and even lead to occlusion of the angle of the eye. Therefore, it is not safe enough to carry out this test without adequate emergency (such as surgery) and must be done with caution.

When doing dilated tests, it is generally avoided to use strong mydriatic drugs. Commonly used are 5% eucatropine (euphthalmine), 1% paredrine hydro bromide, 1% Mydriacyl and 2%. After the horse tropine, etc., and the number of medications and observation methods are confusing, it is recommended to follow the test method prescribed by the glaucoma research collaboration group in China, that is, 3 drops of horse tropine after 2% drop, when the pupil dilation is large to 5mm, start testing Intraocular pressure, 1 time of intraocular pressure every 15 minutes, a total of 4 times, every 2 hours thereafter, a total of 3 times, the following points should be noted when doing the test:

1 While measuring the intraocular pressure and measuring the pupil size, record.

2 For safety, it is not possible to perform dilated tests at the same time.

3 When the intraocular pressure rises to 4.60 kPa (35 mmHg) or more, the angle of the anterior chamber under high intraocular pressure is checked.

4 After the end of the test, should be as soon as possible, if there is elevated intraocular pressure, acetazolamide 250 ~ 500mg orally.

5 After the pupil is reduced and the intraocular pressure drops to normal, the conditional person should observe whether the iris cornea angle has been opened to the pre-test state. If the angle has been fully restored, the patient can leave the hospital because there are a few iris roots. In patients, although the pupil is reduced, the angle of the anterior chamber is not necessarily completely open, so there is still a risk of elevated intraocular pressure.

6 very few patients with negative dilated sputum test, the intraocular pressure suddenly increased after 1 to 4 days of the test, so for the test results of negative results, in addition to the administration of miotic agents, and patients with high intraocular pressure symptoms should go immediately Hospital review.

Some people have performed dilated tests on 132 normal eyes and 146 angle-closure glaucoma. The results showed that the average intraocular pressure increased by 0.33 kPa (1.9 mmHg) after normal eye dilation, the standard deviation was 2.05 mmHg, and the mean plus 2 standard deviations. It was equal to 0.79 kPa (6.0 mmHg), and the intraocular pressure increased by 0.79 kPa (6 mmHg) after the test. The positive result of normal eyes was 2 eyes (1.5%), and the positive result of closed angle glaucoma was 65 eyes (46.4). %), if the intraocular pressure increased by 1.064 kPa (8 mmHg) as positive, the positive angle of glaucoma was 53 eyes (37.9%).

The dilated test may have a higher positive rate for patients with short angles. Because of the risk of this test, it is not appropriate or prudent to use this test for one-eyed patients. This test should cause emergency pressure reduction in patients with extremely high intraocular pressure. Measures, if necessary, surgery.

(5) Pilocarpine-Phenylephrine Test: This challenge test was first advocated by Mapstone as an excitation test for angle-closure glaucoma by first performing a photo of the front of the eye, measuring the intraocular pressure, using 2% pilocarpine and 10%. The phenylephrine solution is alternately instilled once a minute, and then 10% phenylephrine is administered once every half hour. The intraocular pressure is measured and measured. If the intraocular pressure rises above 1.064 kPa (8 mmHg), intravenous injection is given immediately. Acetazolamide 500 mg, and 0.5% Thymoxamine and 2% pilocarpine eye drops, ocular pressure was measured every 1 hour and photographed, and then the ratio of the pupil diameter/corneal diameter (P/C) of the horizontal diameter line on the photograph was measured and calculated.

If the test is negative after 2 hours, further use 2% pilocarpine and 10% phenylephrine eye drops every half hour, continue the test, with the above record, if it is still negative after 1.5h, drop 0.5% Thymoxarmine, end test.

For eyes that are negative in the above test, the test can be repeated for another day. The eye is still photographed first, the intraocular pressure is measured, and the eye drops are applied once a minute with 0.5% tropicamide (Tropicamide) for 3 times. Perform photography once every half hour and measure intraocular pressure. If the intraocular pressure rises above 1.064 kPa (8 mmHg), ie, intravenous injection of acetazolamide 500 mg, 2% pilocarpine eye drops, if after 2 hours, the intraocular pressure rise does not exceed 1.064. At kPa (8 mmHg), 2% pilocarpine was dropped, and the test was terminated.

(6) Dark room plus prone test: In the prone test, if the mechanism of the angle closure is mainly due to the increase of pupillary block force, the factor of pupil enlargement of the iris to the corner of the corner cannot be involved, so some authors designed The dark room plus prone test, that is, the patient stayed in the dark room for 1 to 2 hours as in the dark room test, but the difference is that the prone position must be taken according to the prone test. This provocation test is more positive than the simple dark room test or the prone test.

(7) Neosynephrine (phenylephrine, phenylephrine) dilated test: Because this drug has different ciliary muscle paralysis drugs, there will be no increase in intraocular pressure due to relaxation of the ciliary muscle during dilated pupils, nor will it As a result of the posterior movement of the lens, it is currently used in cases of high-suspicion of high-pleated iris syndrome after peripheral iridotomy to determine whether there is a closure of the angle caused by iris accumulation.

(8) Thymoxamine (Moxiseli) sputum test: Moxiseli is an alpha adrenergic receptor antagonist, and the use of the eye against the pupil opening muscle causes the pupil to shrink, but does not affect the ciliary muscle. Function, so there is no reduction in intraocular pressure and lens advancement due to contraction of the ciliary muscle. Currently, it is mainly used in the identification of angle-closure glaucoma and narrow-angle open-angle glaucoma. The decrease in intraocular pressure may be a closed angle glaucoma; if the angle of the anterior chamber is widened after administration, the intraocular pressure may remain unchanged, which may be a narrow angle open angle glaucoma.

(9) Dark room ultrasound biological microscope angle inspection: This excitation test is the same as the dark room test. The difference is that the technique can be used to observe the changes of the angle of the corner and the surrounding iris and ciliary body in the natural state. In a recent applied study, it was found that using this technique for darkroom testing can increase the specificity of the diagnosis to 100% and the sensitivity to 68.2%.

4. Changes in intraocular pressure: The elevated intraocular pressure of this disease is paroxysmal. The initial onset has obvious interval, lasts only a few hours at night, reaches the highest peak before going to bed, and can naturally relieve after full sleep and rest. With the development of the disease, the duration of high intraocular pressure is longer, and it can be relieved in a few days. Even if it is not relieved by drugs, the intraocular pressure in some cases exceeds the normal range, but it lacks obvious symptoms and maintains good vision. It is difficult to diagnose. In patients with early chronic angle-closure glaucoma, the intraocular pressure is normal between 2 episodes, and the intraocular pressure difference is also within the normal range. However, the developmental cases are recurrent due to the iris. The roots are in contact with the trabecular surface to cause damage to the trabecular tissue. On the other hand, the continuous occlusion of the iris cornea angle, the long attack time often causes different degrees of peripheral pre-irisal adhesion, so its base pressure gradually increases, also in the intermittent period. Can not return to normal intraocular pressure levels.

5. Visual field changes: If the early angle-closure glaucoma fails to receive timely and effective treatment, the angle of the anterior chamber is increased and the intraocular pressure is increased continuously, which may cause optic nerve damage similar to primary open angle glaucoma, and optic disc atrophy. As the cup expands, the optic nerve fiber is lost, and the corresponding visual field damage occurs. The degree of visual field damage of this disease is related to the number of episodes and the duration of high intraocular pressure. If not treated in time, it will eventually become blind.

Diagnosis and diagnosis of primary chronic angle-closure glaucoma

diagnosis

Diagnostic points for chronic angle-closure glaucoma:

1 having an anatomical feature of the eye that produces angle-closure glaucoma;

2 symptoms of repeated mild to moderate elevated intraocular pressure or asymptomatic;

3 The angle of the room is narrow, and the angle of the corner is closed under high intraocular pressure;

4 from the advanced stage to the late stage can be seen similar to the primary open angle glaucoma optic disc and visual field damage;

There were no signs of ischemic damage caused by acute high intraocular pressure in the anterior segment of the eye.

Differential diagnosis

The most important of these is the differential diagnosis of narrow-angle open angle glaucoma. The examination of the angle of the anterior chamber under high intraocular pressure is crucial. If the examination of the angle of the ocular hypotensive state is confirmed to be closed, it can be diagnosed as chronic. For angle-closure glaucoma, if the angle of the anterior chamber is narrow under high intraocular pressure, the open angle is open-angle glaucoma. In addition, special sacral dilatation test can be used for identification, but for recurrent episodes, the function is closed. Secondary damage to the beam network, but no adhesion closure in the angle of the anterior chamber. It is sometimes difficult to make differential diagnosis of such chronic angle-closure glaucoma and narrow-angle open angle glaucoma if the patient has recurrent episodes of elevated intraocular pressure. History, trabecular mesh can be seen in the signs of secondary damage, such as the remaining iris pigment, etc., can make a diagnosis of chronic angle-closure glaucoma, if the above symptoms and signs are not obvious, it is difficult to make a judgment, using light and dark environment An angled examination or an ultrasound biomicroscopy angle check in a light and dark environment can help identify.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.