Volume 40 ·  Issue 01 ·  2004

In recent years, with the continuous development of corneal refractive surgery, wavefront aberration has become one of the hotspots in optical researches at present. However, until now, many people still don't understand the concept of wavefront aberration, and its application is limited to individualized cutting when excimer laser is used to treat refractive errors. This issue publishes the articles "The Concept of Wavefront and Its Relationship with Refractive System" by Ren Zeqin and "Research and Progress of Wavefront Aberration in Human Vision Optics" by Wang Yan, aiming to promote the popularization of knowledge of wavefront aberration and further research.

Jointly launched by the world health organization (WHO) and a number of international non-governmental organizations, the initiative "Vision 2020, the right to see for all" aims to eradicate preventable blindness and visual impairment worldwide by 2020. The initiative is carried out in various forms, such as eye health and community health care, and has received extensive cooperation from many countries and institutions.

Objective to investigate the effects of the distribution of high-order aberrations, pupil diameter, myopia and astigmatism on high-order aberrations in Chinese patients with myopia and astigmatism. Methods the Allegretto Wave wavefront aberrometer designed according to Tscherning principle was used to examine the myopia and astigmatism of 147 eyes before excimer laser in situ keratomileusis (LASIK). The root mean square (RMS) values of high-order aberrations were extracted when the pupil diameter was 4.0, 4.5, 5.0, 5.0, 5.5, 6.0, 6.5 and 7.0 mm, respectively, and compared and analyzed according to the degree of myopia and astigmatism. Results the RMS values of 3rd order to 6th order aberrations in the same eye showed a decreasing trend; The difference between the maximum value and the minimum value of the same order aberration is 6.1 to 36.6 times; When the pupil is small, the myopia degree only affects the secondary spherical aberration (grade 6), and when the pupil is larger, the myopia degree increases both the secondary spherical aberration and the spherical aberration (grade 4). When the pupil diameter is ≥5.0 mm, the secondary coma (grade 5) also increases, but under any pupil diameter, the myopia degree has no obvious effect on the coma aberration.

Objective to investigate how to accurately set the cutting volume during excimer laser in situ keratomileusis (LASIK) and analyze the reasons of refractive power regression after LASIK. Methods 650 patients (1 275 eyes) underwent LASIK surgery were followed up to observe the changes of corneal thickness and refractive status before, during and at 1 week, 1, 3, 6 and 12 months after surgery. Results the corneal thickness measurement showed that the average difference between the corneal cutting depth displayed by excimer laser and the actual corneal cutting depth was (32.15 ± 7.23) μ m. The change of central corneal thickness tended to be stable after 6 months after surgery. The refractive power regression was negatively correlated with age and corneal bed thickness, but positively correlated with preoperative diopter. Conclusion It takes 6 months to stabilize corneal thickness and refractive status after LASIK. Age is one of the main factors affecting the refractive stability after LASIK.

Objective to investigate the clinical effect and safety of laser-induced chorioretinal vein anastomosis (CRVA) in the treatment of non-ischemic central retinal vein occlusion. Methods 34 patients (35 eyes) with non-ischemic central retinal vein occlusion were selected and treated with laser-induced CRVA on the basis of a series of preventive measures for complications. The visual acuity and fundus of patients were routinely examined before and after treatment, and fluorescein fundus angiography was performed. The patients were followed up for 3 to 12 months, with an average of 6 months. Results CRVA was successful in 28 eyes (80%). The retinal hemorrhage was basically absorbed and the edema was improved 1 to 2 months after treatment. Among them, 20 eyes (71%) had improved visual acuity, but no visual acuity decreased. Compared with the natural course of disease, the prognosis of fundus and visual acuity of patients was significantly improved, and no serious complications occurred. 7 cases (7 eyes) had unsuccessful CRVA, and 2 cases (2 eyes) had serious neovascular complications. Conclusion Laser-induced CRVA is an effective method for the treatment of non-ischemic central retinal vein occlusion. CRVA on the basis of appropriate preventive measures for complications can significantly improve the safety of CRVA, but it cannot completely avoid the occurrence of serious neovascular complications.

Objective to observe the effects of small incision phacoemulsification cataract aspiration intraocular lens implantation and related factors on the blood-aqueous humor barrier function. Methods the concentration of aqueous humor protein before and after phacoemulsification cataract aspiration intraocular lens implantation in 60 patients (64 eyes) was quantitatively measured by laser protein cell detector, and the flash values were recorded and compared. The follow-up time was 3 months. Results the average flash values of aqueous humor before, 1 d, 1 week, 1 month and 3 months after phacoemulsification cataract aspiration intraocular lens implantation were (6.94 ± 0.34), (26.27 ± 1.37), (13.96 ± 1.05), (9.07 ± 0.43) and (7.16 ± 0.27) light particle number/ms, respectively, 1 d, 1 week and 1 month after operation were higher than those before operation, and the differences were significant (P<0.05); There was no significant difference between 3 months after surgery and before surgery (P>0.05). The concentration of aqueous humor protein in early postoperative eyes was positively correlated with the age of patients (r =0.400, P =0.001), but not with the gender and eye sex of patients. The blood-aqueous humor barrier function was seriously damaged in patients with intraoperative iris prolapse 1 d and 1 week after surgery. The effect of phacoemulsification cataract aspiration on blood-aqueous humor barrier function can be dynamically evaluated by laser protein cell detector.

Objective to investigate the value of CT and MRI in the diagnosis of optic nerve sheath meningioma. Methods 15 cases of optic nerve sheath meningioma were diagnosed by surgery and pathological examination, and all of them were examined by CT and MRI before surgery. Results Among 15 cases of optic nerve sheath meningioma, enhanced CT only showed intracranial spread in 2 cases; Plain MRI showed intracranial spread in 2 cases; Conclusion Enhanced MRI is very valuable in the diagnosis of the intracranial spread of optic nerve sheath meningioma, which can show the lesions not revealed by enhanced CT and plain MRI. It should be regarded as the routine examination before and after the operation of optic nerve sheath meningioma.

Objective to investigate the clinical manifestations, imaging characteristics and clinical diagnosis points of orbital apex and optic nerve tumors before exophthalmos. Methods the medical records of 22 patients with unilateral orbital tumors without exophthalmos were retrospectively analyzed, including the main symptoms, first manifestations, clinical diagnosis and treatment process and imaging findings. Results Among the 22 patients with tumors, there were 6 cases of cavernous hemangioma, 4 cases of schwannoma, meningioma of optic nerve sheath, malignant tumors of nasal sinus and nasopharyngeal cavity spreading in orbit, 2 cases of posterior ethmoid sinus mucous cyst, 1 case of neurofibroma and optic glioma, 17 cases of visual decline as the first symptom, 3 cases of visual decline combined with diplopia, all patients were diagnosed after CT or MRI. The tumors were located at the orbital apex or originated from the optic nerve. Conclusion the early symptoms of orbital apex and optic nerve tumors are visual dysfunction without exophthalmos. The visual acuity declines slowly and progressively, and the treatment effect of optic neuritis is poor. CT or MRI plays an important role in early diagnosis.

Objective to observe the histopathological changes of conjunctival relaxation. Methods the tissues of 17 patients with conjunctival relaxation and 15 patients with simple cataract in the control group were treated with hematoxylin-eosin staining, Verhoeff elastic fiber staining, Masson trichrome staining and Mallory phospho-tungsten hematoxylin staining. Results the conjunctival tissues of patients with conjunctival relaxation showed conjunctival squamous epithelial hyperplasia, parakeratosis, pigmentation of basal cells with different density, lamina propria interstitial hemorrhage, and elastic fiber reduction. Conclusion the relaxed conjunctival tissues of patients with conjunctival relaxation had pathological changes such as conjunctival epithelial hyperplasia, elastic fiber reduction and chronic inflammatory lesions.The reduction of elastic fiber may be one of the main causes of this disease.

Objective to investigate the effects of high concentration of insulin on the expression of vascular endothelial growth factor (VEGF) in retinal Müller cells cultured in vitro.Methods Immunocytochemistry, in situ hybridization and ELISA were used to qualitatively and quantitatively determine the changes of VEGF expression in rabbit retinal Müller cells cultured in vitro under different insulin concentration.Results Insulin can significantly enhance the expression of VEGF and regulate it through transcription level.Conclusion High concentration of insulin may stimulate the transcription of VEGF gene encoding Müller cells and enhance the expression of VEGF protein, thereby accelerating the neovascularization in diabetic retinopathy.

Objective to investigate the feasibility of transfecting glial cell-derived neurotrophic factor (GDNF) into bovine ocular iris pigment epithelial cells (IPECs) with adeno-associated virus (AAV) as vector to obtain GDNF-expressing transgenic cells. Methods the titer of AAV-GDNF was determined by slit hybridization, and the second generation IPECs were transfected with AAV-GDNF according to the multiplicity of infection (MOI) of 50. The second generation IPECs were cultured in DMEM medium containing 3% fetal bovine serum for 4 weeks without fluid change. The amount of GDNF in the supernatant of cell culture was determined by enzyme-linked immunosorbent assay (ELISA). Results (1) After AAV-GFP transfection, the growth of IPECs was normal, and the expression of GFP began to appear in some IPECs at 4 days after transfection. The expression of GFP was yellow-green under the excitation light of 490 nm by fluorescence microscope, and the expression of GFP in IPECs reached the peak after 8~10 days of transfection. (2) According to the results of ELISA, the content of GDNF in the culture supernatant of AAV-GDNF transfected IPECs was (17.14 ± 1.10) μ g/L. Conclusion AAV-GDNF can effectively transfect IPECs cultured in vitro and express GDNF.

Objective to observe the efficacy of wavefront-guided excimer laser in situ keratomileusis (LASIK) in the treatment of myopia. Methods Sixty-three myopic patients (113 eyes) who underwent Zyoptix wavefront-guided LASIK were taken as the experimental group and 335 eyes who underwent conventional LASIK (Planoscan) at the same time were taken as the control group. The efficacy of the two groups was compared. Results There was no significant difference in postoperative refractive power between the two groups (t-test, P>0.05). The postoperative visual acuity of 33.6% of the affected eyes (38 eyes) in the experimental group was better than that in the preoperative glasses, while that in the control group was 17.0% (57 eyes). When the pupil diameter was 6 mm, the postoperative high-order aberration RMS increased by 100% in the control group, while that in the experimental group increased by 35%.

The short-term efficacy of laser in situ keratomileusis (LASIK) is satisfactory, but its long-term efficacy (5 years or longer) is rarely reported in literature.

The research on laser in situ keratomileusis (LASIK) is increasingly perfect. There are many reports on its surgical methods, clinical efficacy and complications at home and abroad. The Shirmer test and tear film rupture time of patients after photorefractive keratectomy (PRK) and LASIK are different from those of normal controls. The contents of IgA, IgG and IgM in tears of patients after PRK are lower than those before operation, and the changes of other tear components are accompanied by the changes of tear components, which affect the formation of tear film and lead to the changes of normal tear environment of cornea. However, the changes of tear components after LASIK are rarely reported at home and abroad. in this study, the tear components of patients before and after LASIK were quantitatively detected to explore the effect of LASIK on tear components.

The treatment of retinal degeneration is a difficult problem in ophthalmology. A large number of experimental studies have shown that various growth factors and neurotrophic factors can promote the survival of retinal nerve cells, prevent or delay the occurrence of apoptosis, and even induce proliferation [1-3]. In this study, ciliary neurotrophic factor (CNTF) expressing cells encapsulated with sodium alginate-polylysine-sodium alginate (APA) microcapsules were transplanted to treat retinal photoreceptor degeneration from January 2000 to December 2001.

At present, the main cause of failure of allogeneic limbal transplantation is the permanent destruction of stem cells caused by postoperative immune rejection. In this study, the characteristic manifestations of immune rejection after allogeneic limbal transplantation were analyzed by establishing a model of allogeneic limbal transplantation in rats, and the mechanism of immune rejection was preliminarily discussed.

As a visual organ, the human eye has a common physical foundation with optics. In recent years, with the rapid development of science and technology, especially some technological breakthroughs in the field of modern ophthalmology, the theory of wavefront aberration has become the focus of human eye's visual function from a simple concept of physical optics, and even as one of the research directions that may improve the visual function [1], it has attracted increasing attention. Based on the optical system of eyes, this paper summarizes the wavefront aberration which has attracted more attention at present.

On the occasion of the New Year, on behalf of the editorial board and editorial department of Chinese Journal of Ophthalmology, we would like to extend our New Year holiday congratulations to fellow ophthalmologists all over the country! I would like to express my sincere gratitude to the readers, authors, editors and reviewers who have always paid attention to and supported the work of this journal!

Due to the lack of fundus red light reflection for white cataract, the operation of capsulorhexis in phacoemulsification cataract aspiration is difficult. In recent years, in order to obtain an intact anterior capsule annular capsulorhexis of moderate size and effectively ensure the durable stability of intraocular lens position after operation, various capsulorhexis methods have emerged [1-3]. However, some patients with white cataract have large lens capsular bag tension, and the phenomenon of "smoking" in the lens cortex seriously affects the clarity of the surgical field, these factors are easy to lead to the failure of continuous annular capsulorhexis.Since 2001, we have adopted a modified continuous annular capsulorhexis method, that is, lens capsular bag tension reduction capsulorhexis method for phacoemulsification cataract aspiration, and obtained satisfactory results. The results are reported below.

From June 1997 to January 2001, a self-developed double round head lateral hole lacrimal duct anastomosis support tube (abbreviated as a new type lacrimal duct support tube) was applied to lacrimal duct anastomosis with annular lacrimal duct implantation method. The curative effect was remarkable.

Waardenberg syndrome (WS) is a rare autosomal genetic disease involving eyes, ears, skin, hair, bones and digestive tract. It was first reported by Dutch ophthalmologist Waardenburg in 1951 [1]. The main characteristics of the disease are: (1) medial canthus moves externally, corresponding to ectopic inferior lacrimal point; (2) a tall and wide nasal base; (3) Heavy eyebrows, connected eyebrows; (4) heterochromatic iris or bilateral light blue iris; (5) Gray hair on the forehead or juvenile gray hair; (6) Congenital unilateral or bilateral neurological deafness. In 1971, Arias [2] classified the syndrome into type Ⅰ (with medial canthus ectopia, WSⅠ) and type Ⅱ (without medial canthus ectopia) according to whether there was medial canthus ectopia. In 1990, Asher and Friedman [3] classified the syndrome into type Ⅲ (WSⅠ with upper limb abnormalities) and type Ⅳ (WSⅠ with Hirschsprung's colon) according to new clinical symptoms.

Case 1: A 43-year-old male from Myanmar was admitted to the hospital on January 1, 2001 due to blindness in his right eye for 4 months and visual acuity decline in his left eye for 1 month. Four months ago, the patient suffered from burning pain on the skin of his right upper face, forehead and top of his head, followed by clustered blisters and red and foreign body sensation in his right eye. After several days, he lost his right eye. In the past month, the patient came to the hospital due to painless visual acuity decline in his left eye.

Proband (IV1), female, 28 years old, with low vision and photophobia in both eyes since childhood, went to the doctor in April 2001. Past history: no other diseases. Personal history: parents were not intimate married, and the first fetus was delivered naturally at full term. Family history: grandmother, father, two aunts and two uncles all suffered from this disease. Physical examination: normal intelligence, no abnormalities in whole body examination, no microcephaly. Ocular examination: naked eye vision: index/30 cm in right eye, 0.01 in left eye, uncorrectable. Horizontal tremor in both eyes, no conjunctiva congestion, transparent cornea; Horizontal diameter: 9 mm in right eye and 8 mm in left eye.

The patient, a 30-year-old female, came to our hospital on November 8, 2002 because her left eye was injured by a wooden stick for 10 h. Ocular examination: visual acuity: left eye light sensation, upper eyelid skin laceration about 3 cm, eyelid swelling, no eyeball tissue after eyelid opening. CT showed: eyeball dislocation in ethmoid sinus (Figure 1). No abnormality was found in the right eye. The diagnosis was traumatic eyeball dislocation in ethmoid sinus and burst fracture of medial orbital wall. Treatment: under local anesthesia, an arc skin incision was made along the inner and lower edge of the eyebrow arch of left eye, 5 mm from the medial canthus, down to the lacrimal sac area, about 40 mm long, and the skin was incised directly to the periosteum surface. The periosteum, medial canthus ligament and lacrimal sac were peeled off from the bone wall along the incision, and gradually peeled off to the deep orbit. The ethmoid sinus cardboard fracture was seen, and the ethmoid sinus communicated with the nasal cavity. The fracture fragments were removed, part of the nasal orbital margin was removed, and the eyeball was pushed to the top with the index finger for reduction. Intraoperative examination results: conjunctival sac was intact, eyeball was not ruptured, visual acuity was positive, cornea was transparent, and there was no bleeding in the anterior chamber, T-1.

The term "wavefront" appears increasingly frequently in the basic and clinical research of optometry, and is occasionally replaced by "wavefront". However, its general concept and specific relationship with refractive system are not introduced exactly and in-depth at present. This paper explains the above problems for the reference of fellow ophthalmologists.

Member of the Communist Party of China, former director of the Department of Ophthalmology of China Union Medical University and Peking Union Medical College Hospital of Chinese Academy of Medical Sciences, honorary director of the Ophthalmology Research Center of Chinese Academy of Medical Sciences, and former deputy director of the Ophthalmology Branch of Chinese Medical Association