(VI) Clinical manifestations
(I) Symptoms The disease starts insidiously and is often detected only when the other eye is covered. Patients often complain of blurred vision, central dark spot, and distortion.
Patients often complain of blurred vision, central dark spot, and visual distortion. Visual acuity is usually 0.02~0.5, with an average of 0.1.
(ii) Fundus manifestations and clinical staging According to the fundus manifestations in different stages of idiopathic macular fissure formation process.
Gass divided it into four stages (Figure 31-4).
Stage I: At the beginning of the disease, spontaneous contraction of the vitreous cortex in front of the central macular sulcus causes traction in the tangential direction of the retinal surface, resulting in detachment of the central sulcus, disappearance of the reflection of the central sulcus in the fundus, and the appearance of yellow dots (100~200mm) on the surface of the retinal pigment epithelium (RPE) in the central sulcus, which is stage Ia; further contraction of the vitreous cortex in front of the central sulcus, detachment of the central macular sulcus, and the appearance of a Both stage Ia and stage 1b are not accompanied by the separation of vitreous and macular central concavity, nor is there a “true” full-layer macular hole, which is clinically known as impending macular hole, and the visual acuity is mildly reduced to 0.3~0.8. The visual acuity is mildly reduced to 0.3~0.8, and fluorescein fundus angiography can show slight hyperfluorescence of the central macular recess.
Figure 3: Impending macular hole stage I
Stage II: A few days to months after the onset of the disease, the tangential direction of the vitreous is further stretched and a macular hole is formed at the edge of the central notch, gradually enlarging from crescent-shaped to horseshoe-shaped, and finally forming a round hole, often accompanied by a capping membrane. In a few cases, the macular hole starts to form in the center of the central sulcus and gradually enlarges to become an uncovered hole. In recent studies, it has been found that there is no loss of central retinal sulcus tissue during the formation of idiopathic macular fissure, and the so-called “pre-fissure lid” is the concentrated posterior vitreous cortex. The subretinal fluid rim is visible around the macular fissure, and there are yellow vitreous wart-like deposits at the fissure with reduced visual acuity to 0.1-0.6. Fluorescein fundus angiography is moderately hyperfluorescent.
Figure 4 Figure 3 Patient developed stage II macular hole
Stage III: After 2-6 months of the above lesions, the macular fissure enlarges to 400-500μm with or without capping due to retinal tissue shrinkage, which is the stage III macular hole. Yellow vitreous wart-like deposits with subretinal fluid rim, cystic-like changes around the central small concavity can be seen, and visual acuity decreases to 0.02~0.5.
Fig. 5 Stage III idiopathic macular hole
Stage IV:The early stage shows the anterior displacement of macular hole cap membrane, and the late stage shows the complete separation of vitreous body from macula and optic nerve papilla, which is stage 4 macular hole.
Fig. 6 Stage IV of idiopathic macular hole
(III) Natural course of the disease
Stage I macular hole (aura hole): about 50% of cases develop into a full-layered macular hole, and 50% of cases resolve spontaneously after separation of the vitreous from the central macular sulcus.
Stage II macular hole: most cases develop to stage 3 hole after 2~6 months. Most cases develop macular hole size to 400mm or more.
Stage III macular hole: Less than 40% of cases progress to stage VI macular hole. 80% of cases have relatively stable visual acuity. The RPE depigmentation of the retinal detachment area usually occurs after 1 year, and the pigment demarcation line can appear after 6 months. In many cases, the retinal adventitia is present. Occasionally, spontaneous retinal repositioning occurs, and retinal detachment may also occur.
(iv) Contralateral eye
(1) Separation of the vitreous from the central macular sulcus: no risk of macular hole formation.
(2) No separation of vitreous humor and central macular sulcus: the possibility of macular hole formation is <15%.
(3) Macular anterior membrane covering the central concave area, often accompanied by yellow dots: macular hole formation possibility <1%.
(4) Star-shaped clouding in front of the central macular sulcus with retinal radial folds: no risk of macular hole formation.
(5) If yellow dots or rings appear in the macular area, and combined with other manifestations of the aura macular hole, it indicates a high risk of macular hole formation.
(7) Diagnostic points
Since the introduction of fundus coherence optical tomography (OCT), the diagnosis of macular hole is no longer difficult. The diagnosis can be confirmed by OCT scan when the suspicious macular hole is detected by fundoscopy.
(H) Differential diagnosis
1. etiological differentiation: It is necessary to exclude the causes other than idiopathic macular hole, such as trauma, inflammation, high myopia, cystoid macular edema, fundus vascular disease, degenerative diseases, secondary macular edema caused by eclipse retinopathy, etc.
2. morphological differentiation: it should be differentiated from 2 other kinds of vitreous traction macular lesions.
(1) Idiopathic macular anterior membrane: sometimes combined with macular fissure, fundus and OCT examination can clearly diagnose.
(2) Vitreous macular traction syndrome: It often leads to macular traction deformation and macular edema, sometimes coexisting with macular fissure, and OCT examination can confirm the diagnosis.
(3) Laminar macular fissure: OCT examination can clarify whether the macular fissure is total or laminar.
(4) Macular fissure retinal detachment: It often occurs in high myopia. Idiopathic macular fissure often appears around the macular fissure with a shallow detachment halo with the source of the fissure warped, but it rarely occurs in the true sense of retinal detachment.
(IX) Treatment principles and progress
1. The surgical treatment of macular hole used to be a forbidden area, and was only considered when there was a large extent of peripheral retinal detachment. In recent years, due to the research on the pathogenesis of macular hole, it is recognized that the formation of macular hole is closely related to the traction of vitreous body on the tangential direction of macular central recess. Therefore, removal of the vitreous cortex in front of the central sulcus by vitrectomy has been widely carried out to treat macular holes.
The aim of the surgery is to relieve the vitreous macular traction. In stage I patients, removal of the vitreous body, especially the posterior vitreous cortex in front of the macular area, can reset the detached central macular notch. For patients with full macular hole formation, the surgical objectives are multifaceted, including relief of vitreous macular traction, detachment of the anterior macular membrane or inner retinal boundary membrane associated with macular hole development, and intraocular gas filling to allow macular hole closure. For refractory macular tears (e.g., large or recurrent holes), the use of autologous serum, β2 transforming growth factor (TGF-β2) or autologous platelet concentrate applied to the macular hole may increase chorioretinal adhesions in the hole area and induce the hole to close and heal.
2. Indications
(1) Therapeutic vitrectomy: The purpose is to promote the closure of the macular hole and the repositioning of the superficial retinal detachment around the hole.
A. Those who are clearly diagnosed as stage II~IV idiopathic macular fissure, with obvious loss of visual acuity (0.05~0.4) and obvious visual distortion.
B. Those who have macular fissure formation time within one year and are willing to undergo surgery.
(2) In the staging of macular fissure by Gass, stage I macular fissure does not form a full-layered macular hole, and about 1/2 patients with stage I macular fissure can spontaneously resolve, so surgery for stage I macular fissure is mostly not advocated, and surgery can be carefully chosen for patients with high risk of developing a full-layered macular hole.
Whether vitrectomy can prevent the formation of total macular fissure is inconclusive. The results of a multicenter, randomized, controlled clinical study in the United States showed that for patients with stage I macular fissures, the incidence of total macular fissures was 37% and 40% in the vitrectomy group compared with the unoperated observation group (P=0.81), respectively, and the efficacy of prophylactic surgery cannot be confirmed at this time because the number of cases observed is still small. Therefore, the pros and cons of the proposed prophylactic vitrectomy for stage I macular fissure need to be weighed. The “pros” of the surgery are to relieve the mechanical pull of the vitreous on the macula, while the “cons” are the possible risks associated with the surgery, including: the surgical operation may cause total macular The “pros” of surgery are to relieve the mechanical pull of the vitreous on the macula, while the “cons” are the possible risks of surgery, including: surgical operation may cause total macular fissure, peripheral retinal fissure of medical origin, retinal detachment, infection and lens clouding.
3. Surgical methods and progress
The traditional surgical technique is the standard three-incision transciliary vitrectomy with posterior vitreous detachment, sub-total removal of the vitreous, stripping the anterior macular membrane or the inner retinal boundary membrane of the macula, or closing the macular hole with biological agents. Expansion gas/air exchange with 20% to 25% SF6 gas is performed. After surgery, the patient is placed in prone position for about 14 days, and the intravitreal gas is absorbed and normal position is restored.
(1) Microincisional vitreous surgery
In 2002, the 25G transconjunctival sutureless vitrectomy system was introduced, and in 2003, the 23G sutureless vitrectomy system was used for vitreous surgery. Currently, these two vitrectomy devices have been used in idiopathic macular hole surgery. In China, Zhao Mingwei et al. proposed the use of 20G maneuver small incision vitreous surgery also achieved good results and reduced the cost of surgery.
(2) Internal boundary membrane staining technique
Most of the staining techniques used for the removal of the inner boundary membrane are trypan blue, brilliant blue G (BBG), bromphenol blue (BPB), Chicago blue (CB), triamcinolone (TA), and indocyanine green (IGB). Indocyanine green (ICG), etc. Triamcinolone does not stain the inner border membrane, but can make it easily identifiable.
Fig. 7 Postoperatively, the macular hole was closed and the central macular recess was restored in patient 1.
4. Surgical complications
The surgical complications of treating idiopathic macular fissure are similar to those of ordinary vitrectomy, including nuclear cataract, transient high intraocular pressure, medically induced retinal fissure production, macular fissure enlargement, retinal pigment epitheliopathy due to phototoxicity, vascular obstruction, and endophthalmitis. The incidence of nuclear cataract is the highest, up to 12%-90%, and the literature reports that cataract extraction and IOL implantation is required in about 33% of cases 5-16 months after the initial surgery to restore vision to previtreous surgery vision or better in eyes with closed macular fissures. Transient high IOP occurs in about 17.4% of operated eyes, mostly within 3 weeks postoperatively, mainly due to gas filling, and is usually treated symptomatically. If medical fissure occurs, laser sealing should be used instead of condensation sealing as much as possible to reduce the occurrence of postoperative complications, such as macular anterior membrane.
(X) Surgical evaluation and prognosis
The main reasons for macular fissure vision loss are as follows ① There are no retinal photoreceptor cells at the fissure. (2) Superficial detachment of the retina around the fissure. (3) Cystoid edema around the lacunae. ④ Different degrees of degeneration of the optic cells around the lacunae. The cause of the disease can be eliminated by loosening the pull in the anterior and posterior directions of the lacunae and in the tangential direction through vitrectomy; the macular lacunae can be closed by gas filling and biologic factors, and the retinal neuroepithelium can be reset, thus improving the visual acuity and visual distortion and other symptoms.
The results of different studies on the efficacy of different surgical methods for macular lacunae are different; Kelly (1991) and others used vitrectomy alone (52 cases), the lacunae closure rate was 58%, and the visual acuity improvement was 42.3% for more than 2 lines. In recent years, it has been found that the use of autologous platelets, autologous serum, transforming growth factor β2 (TGF-β2), and fibrinogen to fill the macular lacunae during surgery increased the healing of choroidal retinal adhesions at the lacunae and effectively improved visual acuity. In the literature, it has been reported that 91%-100% of macular fissures were closed with vitrectomy combined with TGF-β2, and 83%-90.1% of visual acuity was improved by more than 2 rows, but some operators failed to repeat the same results and found a significant response to postoperative IOP elevation. Recently, Thompson et al. reported that there was no significant difference between TGF-β2 and placebo control in terms of anatomical repositioning of macular fissures and improvement of visual acuity. In the platelet group, the fissure closure rate was 95%, and the visual acuity improvement was 85% for those with more than 2 lines, while the fissure closure rate was only 65% for the vitrectomy group. In a randomized controlled clinical trial by Christensen et al [10], the rate of macular hole closure was significantly higher in the stage 2 versus stage 3 idiopathic macular hole group (100% versus 55% in the stage 2 macular hole group). , 100% versus 55%, and stage 3 macular hole, 91% versus 36%).
The following factors affect the prognosis of the surgery: ① Whether the fissure is closed or not. Poor closure of the lacunae resulted in unsatisfactory visual acuity recovery. Whether the fissure is completely closed after surgery may be related to whether the anterior macular vitreous cortex is cleared during surgery, whether the membrane around the fissure is removed, whether there is still tension around the fissure, and whether the patient’s head position is maintained after surgery. Postoperative complications such as cataract formation, scleral cryopreservation of the pre-retinal proliferative membrane in case of medical source hole, etc. may also have an impact on visual recovery. (3) Intraoperative operation in the macular hole area should be performed with care to avoid instrumentation damage to the retinal tissue in the macular area.
With the advancement of OCT technology, the understanding of the prognosis of idiopathic macular hole has been deepened. Inoue et al [11] examined 53 patients with postoperative macular hole closure using frequency-domain OCT and found that the connection between the inner and outer segments of the photoreceptors may play an important role in the recovery of visual acuity after macular hole surgery. The more severe the postoperative defect of the inner and outer intersegmental connections, the worse the visual prognosis. As time progresses, the connection between the inner and outer segments can be partially restored in some patients, while in others it persists.
(xi) Disease prevention
For non-specific macular fissures with a clear etiology, the occurrence of macular fissures can be prevented by treating the primary disease and by close follow-up examinations. There is no effective prevention method for idiopathic macular fissure.
(XII) Disease care
Macular fissure surgery requires prone position after surgery due to intraocular gas filling, and the duration of prone position depends on the type of intraocular gas filling. The duration of prone position depends on the type of intraocular gas filling, which is usually 1-2 w. At this time, care is provided according to the routine of intraocular filling care after vitreous surgery.
References
1. Zhang Chengfen, Editor-in-Chief Dong Fangtian, Chen Youxin, Zhao Mingwei, Associate Editor, Funduscopy, Second Edition, 2009, Beijing, People’s Health Press
2. Li Xiaoxin, Wang Jingzhao, Editor-in-Chief, Wei Wenbin, Zhao Mingwei, Associate Editor-in-Chief, Vitreoretinal Surgery 1999, Beijing People’s Health Publishing House
3. Gass JDM. Idiopathic senile macular hole: its early stages and pathogenesis. Arch Ophthalmol, 1988, 106: 629
4. Ming-Wei Zhao, Peng Zhou, Xuan Cui, Yu Wang, Xiao-Xin Li,. Manual Small Incision 20-Gauge Pars Plana Vitrectomy. RETINA. 2009, 29:1364-1366