Assessment of Corneal Biomechanical Properties by CorVis ST in Patients with Dry Eye and in Healthy Subjects.

Purpose. To investigate corneal biomechanical properties in patients with dry eye and in healthy subjects using Corneal Visualization Scheimpflug Technology (CorVis ST). Methods. Biomechanical parameters were measured using CorVis ST in 28 eyes of 28 patients with dry eye (dry eye group) and 26 normal subjects (control group). The Schirmer I test value, tear film break-up time (TBUT), and corneal staining score (CSS) were recorded for each eye. Biomechanical properties were compared between the two groups and bivariate correlation analysis was used to assess the relationship between biomechanical parameters and dry eye signs. Results. Only one of the ten biomechanical parameters was significantly different between the two groups. Patients in the dry eye group had significantly lower highest concavity time (HC-time) (P = 0.02) than the control group. Correlation analysis showed a significant negative correlation between HC-time and CSS with marginal P value (ρ = -0.39, P = 0.04) in the dry eye group. Conclusions. The corneal biomechanical parameter of HC-time is reduced in dry eyes compared to normal eyes. There was also a very weak but significant negative correlation between HC-time and CSS in the dry eye group, indicating that ocular surface damage can give rise to a more compliant cornea in dry eyes.

[Application of octopus 101 GKP kinetic and static automated perimetry in the diagnosis of the primary open angle glaucoma].

OBJECTIVE: To investigate the clinical significance of the Octopus 101 GKP kinetic and static automated perimetry in the diagnosis of the primary open angle glaucoma (POAG). METHODS: Thirty POAG patients (POAG group) and 34 normal individuals (control group) were detected with Octopus 101 GKP static and kinetic perimetry with GKP and TOP program from October 2006 to March 2007. The visual acuity, intraocular pressure (IOP), cupping/disc (C/D) ratio, mean defect (MD), loss variance (LV), areas of isopter, and testing time were analyzed. RESULTS: The mean visual acuity, mean IOP and mean C/D ratio were significantly different between POAG group and control group (P = 0.000), and so was the testing time (P = 0.001). The mean test time was (307.78 +/- 134.50) s in the POAG group and was (228.12 +/- 75.33) s in the normal group. No linear correlation was found between the IOP and the areas of isopter or MD between these two group. The visual parameters (I 2e and III 4e) as to the areas of isopter of POAG were significantly different (P = 0.000), and so were the MD, LV and areas of isopter (P = 0.000). Static perimetry had a sensitivity of 80% and a specificity of 45%, and kinetic perimetry had a sensitivity of 86% and a specificity of 63%. The combined method of static and kinetic approaches had a sensitivity of 90%. CONCLUSIONS: The Octopus 101 GKP static and kinetic perimetry can perform an automated test that combines the advantages of both kinetic and static perimetry, resulting in a decreased subjectivity and individual difference by adjusting the response time and improved accuracy of test results. By changing stimulus size, background illumination, and stimulus angular velocity, the combination of the kinetic and static test may provide a higher sensitivity in the diagnosis of the early stage of POAG, particularly in patients with early peripheral visual field defect.

[The effect of surgical treatment on thyroid-associated ophthalmopathy].

OBJECTIVE: To evaluate the effect of muscle surgery on strabismus caused by extraocular muscle for thyroid-associated ophthalmopathy (TAO), and assess the change of vision acuity, intraocular pressure, visual field and blood flow velocity in central retinal artery that made by surgery treatment. METHODS: Recession and release of the extraocular muscles were used in 17 TAO patients (20 eyes) with strabismus caused by the change of extraocular muscles. In those patients one of them was undergone superior rectus tendon resection and other one was undergone superior rectus suspension. Another patient right eye was undergone inferior rectus recession and the left one with superior rectus recession. For rest of 14 patients with 17 eyes inferior rectus recession was performed. The vision acuity, intraocular pressure, visual field, and blood flow velocity in central retinal artery were measured pre- and post-operatively. RESULTS: In 17 patients (20 eyes), 5 eyes vision acuity improved two or more lines and 15 eyes was unchanged postoperatively. Intraocular pressure and mean defect of visual field showed statistically significance (P < 0.01). The peak systolic velocity (PSV) and the end diastolic velocity (EDV) were significantly increased, and the resistance index (IR) was significantly reduced (P < 0.05). CONCLUSION: Muscle surgery of strabismus caused by extraocular muscle for TAO in the quiescent period can eliminate strabismus, decrease intraocular pressure, improve visual field and blood flow velocity in central retinal artery.

[Visual fields changes in chronic angle closure glaucoma patients after their intraocular pressures were well controlled].

OBJECTIVE: To investigate the progression of visual field loss and to explore the prognosis of glaucomatous optic neuropathy in patients with chronic angle-closure glaucoma (CACG) after their intraocular pressures were well controlled under 21 mmHg. METHODS: Forty-seven eyes of 29 patients in the Department of Ophthalmology in PUMC Hospital were included. All the patients had at least two separate tests of visual fields using the 24-2 program of the Humphery Visual Field Analyzer after their intraocular pressure were well controlled under 21 mmHg after sugery. The visual fields of patients were followed routinely for at least 1 year. In addition, all patients were divided into 2 groups according to follow-up period: 1-2 years group and over 2 years group. Visual field scores were calculated with the Advanced Glaucoma Intervention Study (AGIS) method. The visual fields were divided 5 sections and the sensitivity and defect depth of each section were calculated. RESULT: No statistically significant differences were found in terms of AGIS scores, localized sensitivities and localized defects within the time interval of the observation. CONCLUSION: Glaucomatous optic neuropathy is not likely to progressively deteriorate in CACG cases once their intraocular pressure are well controlled under 21 mmHg.