Volume 51 · Issue 06 · 2015

The International strabismus association conference has a history of fifty years until now. It's the most influential academic communication forum for the worldwide doctors and related scientists or technical carers in strabismus and amblyopia area. The conference gathered the top-level experts. The latest clinical/research achievements of strabismus, amblyopia in the field of binocular vision and ocular motility have been showed. The breakthroughs in the etiology study of incomitant strabismus have been and are being transformed into new therapeutic concepts and techniques. Re-adjust the competition between dominant and amblyopic eye using binocular stimulation methods may overcome the existing defects of monocular occlusion therapy, expand new interventional methods to treat amblyopia, and represent the future trends of amblyopia therapy. In this paper, we will introduce the main contents of the XII ISA meeting and spread knowledge of strabismus/ amblyopia promoting directions in order to provide reference ideas for the clinicians and research colleagues in this field.(Chin J Ophthalmol, 2015, 51: 401-405)

Strabismus is a deviation of the visual axes relative to each other and is a very common eye disease. Strabismus is not only a cosmetic disease but more importantly damage to visual acuity, binocular vision and stereopsis. There are many different strabismus forms. It is very difficult to accommodate all the different clinical forms with only one classification. Different author has different classification because of different concerns. In order to avoid clinical confusion and provide references for clinicians, literatures from mainstream domestic and international journals and new revised classification by Chinese Association for Strabismus and Pediatric Ophthalmology were reviewed in this paper. (Chin J Ophthalmol, 2015, 51: 406-407)

Strabismus is a common clinical disease in ophthalmology, with a prevalence of about 3%. There are many kinds of strabismus, and there is no perfect clinical classification method at present. Different authors and monographs at home and abroad have different degrees of differences in the classification of strabismus due to different emphases and factors considered, which often confuse beginners and non-strabismus ophthalmologists and produce certain troubles for clinical work.

In order to standardize and unify the writing of examination records and medical records of strabismus, make them in line with international standards, so as to make the analysis and clinical diagnosis of strabismus cases more clear and definite, and better promote the academic exchange of strabismus specialty, after discussion with all experts of strabismus and pediatric ophthalmology group of Chinese Medical Association Ophthalmology Branch, the English abbreviations of international commonly used terms related to strabismus and the examination recording methods were introduced^[1,2,3,4,5]The summary is summarized below.

The sclera is mainly composed of collagen fibrous tissue, and its inflammatory response should belong to the category of collagen fibrosis in nature, that is, autoimmune or autoallergic diseases^[1]。 Zhou Yumei et al^[2]The published "Clinical Analysis of 90 Cases of Superficial Scleritis and Scleritis" summarizes a series of cases of superficial scleritis and scleritis from the aspects of clinical manifestations, complications and related diseases, and provides important data for us to comprehensively understand the inflammatory response of sclera. In the preliminary analysis of the etiology of scleral inflammatory reaction, the study found that local infectious factors (especially postoperative infection) accounted for 11.1% of patients with scleritis, which shows that infectious scleritis cannot be ignored in the clinical diagnosis and treatment. Since this article does not carry on more in-depth research and discussion on infectious scleritis, in view of the characteristics of complicated clinical manifestations, difficult treatment and poor prognosis of infectious scleritis, the author will analyze, summarize and differentiate the diagnosis and treatment points of infectious scleritis and immune scleritis.

To investigate the effect of superior oblique tucking on the status of ocular torsion.

It was a retrospective case series study. We reviewed the records of 25 patients underwent superior oblique tucking for treatment of superior oblique palsy in Tianjin Eye Hospital from January 2012 to and August 2013, among them, there were 12 patients had undergone inferior oblique myectomy or inferior rectus recession before this operation. All clinical records, including eye movement, vertical deviation, abnormal head position, Bielschowsky test et al were analyzed. Objective cyclotorsion were examined pre-operation, as well as 1, 30 days post-operation with fundus photograph. The photographs were transferred to a computer and then the fovea- disa angle (FDA) was measured by a software for drawing pictures. The difference of the two eyes was compared by the pairedt-test, and the difference of the two groups was compared by the one-way analysis of variance.

All patients had no more than 12 PD vertical deviation and significant abnormal head position before the operations. After underwent superior oblique tucking from 6 mm to 10 mm, their vertical deviation were less than 3 PD, and symptom of unacceptable abnormal head position were ameliorated or disappeared. In 25 cases of the monocular eye involvement, FDA was - 10.60°±4.93° in the affected eyes preoperatively, while it was -9.67°±5.47° in the fellow eyes. There was also no statistically significant difference between two eyes (t=0.54, P=0.59). The combined FDA in both eyes were -20.27°±6.00° and -10.53°±8.04°, -10.83°±7.38° preoperatively, 1, and 30 days after operation. The comparison of objective ocular cyclotorsion for both eyes showed significant difference pre-and post-operation (F=14.81,P<0.01).

Superior oblique tucking can correct ocular excyclodeviation effectively, and simultaneously correct little vertical deviation. It's good to ameliorate abnormal head position. (Chin J Ophthalmol,2015,51:417-423)

To evaluate the effect of integrated anteriorization of inferior oblique muscle combined with recession of superior rectus to treat large hypertropia following absence of inferior rectus.

It was a retrospective case series study. Integrated anteriorization of inferior oblique muscle means transposing inferior oblique muscle 8–10 mm posterior to the insertion directly to original insertion of inferior rectus without myotomy. We reviewed 5 patients with absence of inferior rectus muscle, who treated by integrated anteriorization of inferior oblique muscle combined with recession of superior rectus. The pre and post-operative vertical deviation in primary position, ocular motility, and abnormal head position were compared. The patients were followed up from 6 to 18 months, with average as 10.8 months.

Postoperatively, 4 patients showed orthophoria in primary position and 1 patient had 10 PD hypotropia. The infraduction deficits improved from - 3.0 to -1.6. Meanwhile, there had been an average of- 2.0 mild supraduction limitation. Abnormal head position (AHP) disappeared in 2 patients with AHP before operation. All the patients showed no change of cyclodeviation on fundus photograph. 5 patients were satisfied with the improvement of the appearance, and the follow-up results were stable, no other surgery again.

Integrated anteriorization of inferior oblique muscle combined with recession of superior rectus was an effective surgical selection to treat hypertropia with absence of inferior rectus muscle. This procedure doesn't need to cut off the inferior oblique muscle. The more convenient surgical procedure can reduce the risk of bleeding.(Chin J Ophthalmol, 2015, 51:424-428)

Brown syndrome is characterized by limitation of elevation in adduction, with complex mechanisms involving muscle, tendon, and trochlea. Here, we investigated mechanisms of Brown syndrome by magnetic resonance (MR) imaging.

It was a retrospective case series study. Fourteen patients with unilateral Brown syndrome between 3 and 54 years of age (10 cases of congenital and 4 cases with acquired disease) were included in the study. All patients underwent complete ophthalmic and orthoptic evaluation. Imaging of the ocular motor nerves at the brainstem was performed on 3D - FIESTA sequence, the orbits were imaged with FSE T1、T2WI using surface coils.

Nine of 10 with congenital Brown syndrome demonstrated hypoplasia of the superior oblique (SO) of the affected side. Abnormal low signal intensity in the trochlea area was found in one patient. Three of 4 acquired patients had a history of trauma and were demonstrated fracture of the trochlea, extensive scarring, and superior orbital fracture. One acquired case was demonstrated scarring of anterior part of the SO and hypoplasia ofthe posterior part.

Brown syndrome consists of a series of diseases. Their clinical features are quite similar while their anatomical mechanism varies in numerous ways. Therefore, based on patient's individual pathophysiology, the management in Brown syndrome should be personalized. (Chin J Ophthalmol,2015,51:429-433)

To study the thickness and width of extraocular muscles by high-resolution magnetic resonance imaging (MRI).

Cross-sectional study. Sixty eight normal subjects between 2.0 and 50.0 years of age, mean age was (21.2±2.1) (SD) years old, male 34, female 34. Extraocular muscles in the orbits were scanned with SE/T2WI coronal and oblique-coronal planes perpendicular to optic nerve, and within 1.5 mm thick planes. The thickness and width of the extraocular muscles in the maximum planes were measured in 68 normal subjects on oblique- coronal planes MR images. The vertical diameter of the medial rectus muscle and lateral rectus muscle indicated width, horizontal diameter indicated thickness. The vertical diameter of the superior rectus muscle and inferior rectus muscle indicated thickness, horizontal diameter indicated width. Vertical diameter of the muscle belly is from the top edge to the bottom edge, horizontal diameter of the muscle belly is from the innermost to the outermost edge. The differences in diameters of bilateral extraocular muscles were evaluated by the independent sample t statistical test. Superior oblique muscle was considered as a reference in each subject to calculate the ratio of the other rectus muscles and the superior oblique muscle in diameter and to compare the relationship of the extraocular muscles in the same plane.

The extraocular muscles of normal subjects were symmetrical on the two sides. There were no statistically significant differences between the bilateral extraocular muscles (medial rectus muscle, lateral rectus muscle, inferior rectus muscle and superior rectus muscle) in the thickness and width (t values respectively were 0.043, 0.025, 0.043, 0.032, 0.001, 0.601, 0.667, 0.021, 0.032, 0.005, all P>0.05). The ratio of the rectus muscles (medial rectus muscle, lateral rectus muscle, superior rectus muscle, inferior rectus muscle) and the superior oblique muscle in thickness respectively were (1.15±0.14), (1.04±0.14), (1.07±0.19), (1.39±0.22). The relationship of the thickness of extraocular muscles in the maximum planes were: inferior rectus muscle > medial rectus muscle > superior rectus muscle > lateral rectus muscle, and the thickness of 91% superior rectus muscle was close to lateral rectus muscle. The ratio of the rectus muscles (medial rectus muscle, lateral rectus muscle, superior rectus muscle, inferior rectus muscle) and the superior oblique muscle in width respectively were (1.71±0.27), (2.07±0.28), (1.62±0.29), (1.50±0.21). The relationship of the width of extraocular muscles in the maximum planes were: lateral rectus muscle> medial rectus muscle> superior rectus muscle> inferior rectus muscle.

The thickness and width of all the extraocular muscles follows a certain rule. Measurements of extraocular muscles using MRI should be done on coronal and oblique - coronal planes MRI scan simultaneously. The sizes of extraocular muscles can be assessed by observing the symmetry of the extraocular muscles on the two sides on coronal plane and the usual rule of extraocular muscles on oblique- coronal plane. (Chin J Ophthalmol, 2015,51:434-438)

To evaluate the feasibility of independently developed digital eye tracker in determining the efficacy of congenital idiopathic nystagmus (CIN) surgery.

Aprospective selfpairing study. The surgical efficacy was evaluated by independently developed eye tracker in 16 CIN patients. The null zone and the frequency, amplitude, intensity of nystagmus in various gazing position were recorded with eye tracker pre and post operatively. The consistency of null zone determined by digital eye tracker and clinical investigation were evaluated. The preoperative and postoperative rectification of horizontal and vertical nystagmus in the horizontal direction of individual patient were compared by paired samples t-test. The improvement or aggravation quantity were recorded by comparing preoperative and postoperative intensity of nystagmus every 5°within 25°.

The null zone got from digital eye tracker and clinical investigation were highly consistent (r=0.952,P<0.01). The horizontal and vertical intensity improved in 9 patients (t=2.335-6.609, P<0.05) and 5 patients (t=2.176- 5.471,P<0.05) respectively after surgery. There were 67.63% (117/173) horizontal intensity and 69.94% (121/173) vertical intensity improvement.

The independently developed digital eye tracker can quantitatively evaluate the pre and post-operative nystagmus and analyze the surgical efficacy for CIN patients. (Chin J Ophthalmol, 2015, 51:439-444)

To report the clinical results of femtosecond laser assisted lamellar keratoplasty (FS-LK).

Retrospective study. Twenty eyes of 17 patients who were treated with FS-LK were enrolled in this study. The preoperative visions were from 0.02 to 0.4. During the operation, the grafts were prepared with a depth of 400 - 600 μm according to the character of the affections.

During the follow-up period, the visions of 18 eyes (90%) were better than preoperative ones. One of them was equal to 0.8. The best corrected visual acuities of 18 eyes (90%) were better than or equal to 0.5, one of which was 1.0. The astigmatisms of 15 eyes were under 3.00 diopters at one year after operation. During the operation of two cases, the paracentral cut occurred. Two patients experienced corneal opacity, and two cases had high astigmatisms after operation. Only one eye experienced immune rejection at one year after operation.

The FS - LK appears to be a good alternative surgical method for patients with corneal diseases because of the great manipuility and excellent postoperative results, but more research is needed. (Chin J Ophthalmol, 2015, 51:445-449)

To investigate the permeability and saturation characteristics of riboflavin in sclera tissue, in order to explore a reasonable dosage regimen in sclera cross- linking.

Experimental study. Five human cadaver eyes were also included in this study, every eye was cut into seven sclera stripes and then 0.1% riboflavin solution was dripped to the sclera stripes for 5, 10, 15, 20, 25, 30minutes respectively. After that,the stripes were made into frozen sections and observed by confocal microscope. To calculate the mean fluorescence density and compare with each other. In addition, 36 New Zealand rabbits were randomly divided into group A and B groups. Each group was divided into six subgroups. In group A, 0.1% riboflavin solution was dripped to the sclera of right eye for 5, 10, 15, 20, 25 and 30 minutes respectively. In group B, 0.5% ribof lavin solution was dripped to the sclera of right eye for 5, 10, 15, 20, 25 and 30 minutes respectively. The left eye were given with physiological saline as blank check. Executed the rabbits to take out the eye and then the nose upper quadrant of the equator sclera was taken to made into frozen sections which were observed by two- photon microscope. To calculate the mean fluorescence density and compare the six subgroups in every group respectively, and compare the subgroups with the same riboflavin- applicated time between group A and B respectively.

The fluorescence intensity of sclera gradually strengthened with the longer riboflavin-applicated time, but there was no statistical difference between 20 minutes and the longer time groups (P>0.05). With the same riboflavinapplicated time in rabbit sclera, the fluorescence intensity of 0.5% concentration group was higher than 0.1% concentration group (P<0.05).

The riboflavin reached an saturation level in the sclera of human cadaver eyes and rabbit eyes after 20 minutes application. The higher concentration of riboflavinapplicated, the higher concentration of riboflavin in the rabbit sclera. (Chin J Optholmol, 2015, 51: 450-454)

To investigate changes in refractive status and ocular length in guinea pigs during the early time of myopic recovery for the causes of recovery.

Exp guinea pigs wore a-5.00 D lens on one eye from 4-18 days, which was then removed for 48 hours. At 18 and 20 days of age, each eye was evaluated for refractive status and ocular length of the eye.

The right eyes treated with -5 D lenses for 12 days developed (- 2.00±1.50) D (P=0.04) of myopia and had an increase in axial length of (0.033±0.025) mm compared to the left eyes (P=0.04). After 48 hours of recovery, the difference between the two eyes was reduced to (- 0.72±0.86) D (P=0.13), but the ocular length still had significant difference (0.031±0.022) mm (P=0.04). During the myopia recovery early period, the refractive status and ocular length changed in the same direction in the left eyes but in the opposite way in the right eyes.

Guinea pigs treated with -5.00 D lenses for 12 days developed explicit relative axial myopia. After removal of the lens for 48 hours, myopia significantly recovery can be due to the thickening of choroid and the reduction in ocular growth. (Chin J Ophthalmol, 2015, 51:455-457)

The patient was a 19-year-old male. On February 25, 2009, he was transferred from the local hospital to the Department of Ophthalmology, Dongfang Hospital, Beijing University of Traditional Chinese Medicine for integrated Chinese and Western medicine treatment due to traumatic optic neuropathy in both eyes caused by head and face trauma for 5 months. The patient suffered from blurred vision in his right eye and reduced vision in his left eye after injuring his head and face in a car accident 5 months ago, accompanied by mild redness in his right eye, no eye pain, eye swelling, headache and vomiting. He was treated with drugs to nourish nerves and improve circulation (details unknown) with "multiple comminuted fractures of his right head and face and traumatic optic neuropathy in both eyes" in the local hospital, but the binocular visual function did not improve significantly. Past physical health, denied history of refractive error, chronic conjunctivitis, denied history of hypertension, diabetes, heart disease, no history of high-dose glucocorticoid use, no family history of glaucoma. Examination after admission, visual acuity: 0.05 in the right eye, correction did not improve, and 1.0 in the left eye. IOP: 26 mmHg (1 mmHg =0.133 kPa) in the right eye and 17 mmHg in the left eye. Absence of bone in the right frontotemporoparietal bone and orbital bone. There is no protrusion or depression in the right eye, and the conjunctiva is mild congested (Figure 1), the cornea is transparent, the anterior chamber is mid-deep, the pupil is round, 5 mm in diameter, the reflex to light is retarded, and the lens is transparent. No abnormalities were observed in the anterior segment of the left eye. The papilla of both eyes was pale in color, with clear borders, cup-to-disc ratio of 0.3, retinal vascular movement was roughly normal, arteriovenous vascular diameter ratio was 2: 3, and the macular center was unclear. Dynamic visual field examination: the right eye could not be detected, and the left eye had temporal 1/2 quadrant visual field defect. Electrophysiological examination showed that the peak latency of the right eye flash VEP and the left eye pattern VEP P100 was delayed and the amplitude decreased. OCT examination showed thinning of optic nerve fibers in both eyes. Anterior chamber gonioscopy: Both eyes were open angles, pigment grade II, no neovascularization and no angular recession were seen. Preliminary diagnosis: traumatic optic neuropathy in both eyes; Primary open-angle glaucoma in right eye to be examined; Ocular hypertension in the right eye to be examined.

aneurysm is a common localized cystic dilatation disease of arterial vessels. The etiology is often related to arterial vascular injury, disease (such as atherosclerosis or sepsis) or congenital defect. Due to the anatomical course of the internal carotid artery in the cranium, aneurysm of internal carotid artery (AICA) may cause ocular manifestations such as oculomotor nerve paralysis, abducent nerve paralysis, significant decrease in visual acuity, visual field defect, etc^[1,2]And even cause serious complications such as subarachnoid hemorrhage^[3]Ophthalmologists sometimes have insufficient understanding of this disease, and misdiagnosis and missed diagnosis will occur. Three misdiagnosed cases of internal carotid artery aneurysm causing visual impairment diagnosed and treated by the Department of Ophthalmology of Peking Union Medical College Hospital are reported as follows.

The patient was a 65-year-old female. Because the visual acuity of both eyes gradually decreased for 6 months and aggravated for 3 months, he went to the Department of Ophthalmology of the Fourth Hospital of Xi' an. The patient had no history of eye surgery and trauma, and his parents were not close relatives, and there was no family history. The whole body examination showed no obvious abnormalities. Eye examination: naked eye visual acuity was 0.25 for the right eye and 0.25 for the left eye; The corrected visual acuity was 0.4 for the right eye and 0.3 for the left eye; IOP was 16.4 mmHg (1 mmHg =0.133 kPa) in the right eye and 12.4 mmHg in the left eye; The cornea of both eyes is transparent, the anterior chamber is clear, the pupil is round, and it is sensitive to light. The lens is opaque, and the retina is vaguely flat in the fundus of the eye. After dilated pupil examination, the right eye lens peripheral defect from 1: 00 to 3: 00 (Quintessence Picture 1), and there was no obvious defect in the lens of the left eye. Ultrasound biomicroscopy showed that the right eye lens echo was enhanced, morphology was abnormal, and there was a partial defect above the nose, but no obvious abnormality was found. Clinical diagnosis: right eye lens defect; Age-related cataract in both eyes.

The patient was a 76-year-old male. Because of blurred vision in his right eye for 1 year, he went to Tianjin Eye Hospital. History of trauma and systemic medical history were denied. Eye examination: right eye visual acuity 0.4, intraocular pressure 11 mmHg (1 mmHg =0.133 kPa); The conjunctiva was not congested, the sclera was not yellowed, the corneal epithelium was intact, the stroma was not edema, the endothelium was transparent, and there was no retrocorneal deposition; The peripheral anterior chamber is of varying depth and clear water; The pupil was round, with a diameter of 6 mm. There was no iris atrophy and adhesion after drug-induced dilatation of the pupil, and iris tremor was seen. The lens cortex and nucleus are opaque, displaced to the nasal side, and the lens suspensory ligament is visible on the temporal side (Quintessence Picture 1）； The fundus of the eye is vaguely visible, the boundary of the papilla is clear, the retina is in place, and the macular area is not clearly seen. For ultrasound bioscopy, seeQuintessence Picture 2。 B-ultrasound examination revealed vitreous opacity in the right eye. Clinical diagnosis: right eye lens subluxation; Cataract in the right eye.

The patient was a male, 8 years old. Because of poor vision in both eyes since childhood, he went to Tianjin Eye Hospital. Eye examination: visual acuity was 0.6 for the right eye and 0.2 for the left eye; The conjunctiva of both eyes is not congested, the cornea is transparent, the anterior chamber is clear, and the lens is transparent; For fundus examination, seeQuintessence Picture 1。 Coherence optical tomography examination is shown inQuintessence Picture 2。 Clinical diagnosis: congenital retinoschisis in both eyes.

Intermittent exotropia is the most common type of exotropia, and also is one of the most difficult types of strabismus to deal with. Surgery is the main choice of treatment and non-surgical treatment is used only under certain indications. Long - term outcomes of the surgery for intermittent exotropia are related to many factors, such as age, course of the disease, perceptual state of visual cortex, timing of surgery, types of intermittent exotropia, the surgical methods, preoperative measurements of exodeviations, target angle of surgery, postoperative treatment of overcorrection or undercorrection, and so on. It is significant to pay attention to these issues to improve success rate of the surgeries. In this paper, recent progress of clinical studies of intermittent exotropia were reviewed to arouse the attentions of domestic ophthalmologist to the standardization of diagnosis and treatment of intermittent exotropia. (Chin J Ophthalmol, 2015, 51: 465-469)

Many forms of synaptic plasticity require NMDA- type glutamate receptors (NMDAR). These tetrameric receptors consist of two obligatory NR1 subunits and two regulatory subunits, usually a combination of NR2A and NR2B. In the neonatal visual cortex NR2B-containing NMDAR predominate, after thatvisual experience facilitates a developmental switch in which NR2A levels increase relative to NR2B. In this review, it puts emphasis on the role and the regulation of this shift as well as the effect on synaptic plasticity. (Chin J Ophthalmol, 2015,51:470-476)

Intraocular pressure(IOP) is considered the main risk factor for the development and progression of glaucoma. The major treatment is to reduce the intraocular pressure. However, the damage of optic nerve may continue to progress despite lowering patients' IOP to the target levels. High ocular perfusion pressure (OPP) fluctuations could have detrimental effects in eyes with glaucoma which confirmed that vascular factor is one of the pathogenesis of glaucoma. This review article discussed the research progress of relationship between ocular perfusion pressure and glaucoma including its definition, calculation, epidemiological studies, fluctuation and autoregulation. We also discussed whether it was secondary to changes in intraocular pressure, blood pressure or both. We expect ocular perfusion pressure fluctuations could provide evidence for evaluating glaucoma progress. (Chin J Ophthalmol,2015,51 :477-480)