Zhonghao Wang

Quantitative Measurements of the Ciliary Body in Eyes with Malignant Glaucoma after Trabeculectomy Using Ultrasound Biomicroscopy

PURPOSEnTo evaluate and compare the structural differences of the ciliary body in eyes with and without malignant glaucoma.nnnDESIGNnCross-sectional study.nnnPARTICIPANTSnTwenty-seven consecutive patients diagnosed with malignant glaucoma in 1 eye after trabeculectomy were recruited. They were all originally diagnosed with primary angle closure (PAC) or PAC glaucoma (PACG). Twenty-seven PAC/PACG eyes of 27 patients who had undergone uneventful trabeculectomy in the same period were also recruited. They were comparable with the fellow eyes of the malignant glaucoma patients in terms of surgical type, glaucoma type, and stage.nnnMETHODSnA-scan ultrasonography and ultrasound biomicroscopy measurements were performed on the eyes with malignant glaucoma, the fellow eyes of the patients with malignant glaucoma, and the matched eyes.nnnMAIN OUTCOME MEASUREMENTSnCiliary body parameters included maximum ciliary body thickness (CBTmax), ciliary body thickness at the point of the scleral spur (CBT0) and 1000 μm from the scleral spur (CBT1000), anterior placement of the ciliary body (APCB), and the trabecular-ciliary process angle (TCA). Biometric measurements including axial length, central anterior chamber depth (ACD), pupil diameter (PD), anterior chamber width, and lens vault (LV) were also recorded.nnnRESULTSnAverage CBTmax were 0.545±0.088 (mean ± standard deviation), 0.855±0.170, and 0.960±0.127 mm in eyes with malignant glaucoma, their fellow eyes, and the matched eyes, respectively. Average APCB were 0.860±0.176, 0.608±0.219, and 0.427±0.139 mm, respectively. Average TCA were 18.49±4.12, 41.79±17.27, and 48.53±10.38 degrees, respectively. The CBTmax, CBT0, CBT1000, and TCA were smaller, whereas APCB was larger in eyes with malignant glaucoma compared with their fellow eyes (Pu2009<u20090.01). The fellow eyes had larger APCB and smaller CBTmax and CBT0 than the matched eyes (Pu2009<u20090.05). The ACD, anterior chamber width, and PD were smaller, whereas LV was larger in eyes with malignant glaucoma compared with their fellow eyes (Pu2009<u20090.05). No differences were found in the ACD, anterior chamber width, PD, or LV between the fellow eyes of malignant glaucoma and matched eyes (Pu2009>u20090.1).nnnCONCLUSIONSnThe ciliary bodies were thinner and more anteriorly rotated in eyes with malignant glaucoma as well as in their fellow eyes, which may be the predisposing factor for malignant glaucoma.

A simple and evolutional approach proven to recanalise the nasolacrimal duct obstruction

Aim: To evaluate a new approach of recanalisation of nasolacrimal duct obstruction (RC-NLDO) in the treatment of the nasolacrimal duct obstruction (NLDO) and chronic dacryocystitis. Methods: 583 patients with 641 eyes suffering from NLDO and chronic dacryocystitis were enrolled in this study. The RC-NLDO was performed in 506 eyes, with 135 eyes undergoing external dacryocystorhinostomy (EX-DCR) as controls. Patient follow-up for 54 months was evaluated by symptoms, dye disappearance test, lacrimal irrigation and digital subtraction dacryocystogram. The RC-NLDO was also performed in 12 rhesus monkeys for histopathological examination. Results: The clinical success rates were 93.1% in 506 cases of RC-NLDO and 91.11% in 135 cases of EX-DCR. The success rates for second surgery were achieved in 85.19% on RC-NLDO and 40.0% on EX-DCR. No major intra- or postoperative complications were observed in the RC-NLDO group. The mean operative duration was 12.5 min for RC-NLDO and 40.3 min for EX-DCR (p<0.001). A pathological study in rhesus monkeys demonstrated that the RC-NLDO wounded epithelium in nasolacrimal duct healed completely within 1 month without granulation tissue formation. Conclusion: The findings demonstrate that the RC-NLDO is a simple and effective approach proven to recanalise the obstructed nasolacrimal duct with a comparable success rate to EX-DCR.

Novel air-injection technique to locate the medial cut end of lacerated canaliculus

Locating the medial cut end of the severed canaliculus is the most difficult aspect of canalicular repair, especially in patients with more medial laceration, severe oedema, persistent errhysis and a narrow canaliculus. Irrigation is a widely used technique to identify the cut end; however, we found that air injected through the intact canaliculus with a straight needle failed to reflux when the common canaliculus or lacrimal sac was not blocked. We describe a simple, safe and efficient air-injection technique to identify the medial cut edge of a lacerated canaliculus. In this method, we initially submersed the medial canthus under normal saline, then injected filtered air through the intact canaliculus using a side port stainless steel probe with a closed round tip. The tip was designed to block the common canaliculus to form a relatively closed system. The efficiency of this novel air-injection technique was equivalent to the traditional technique but does not require the cooperation of the patient to blow air. Using this technique, the medial cut end was successfully identified by locating the air-bubble exit within minutes in 19 cases of mono-canalicular laceration without any complication.

Quantitative Measurements of the Ciliary Body in Eyes With Acute Primary-Angle Closure.

PURPOSEnTo compare the structural differences of the ciliary body in patients with acute primary-angle closure (APAC) and normal subjects.nnnMETHODSnForty-four patients with APAC in one eye and 25 eyes from 25 age-matched normal subjects were consecutively recruited. A-scan ultrasound and ultrasound biomicroscopy (UBM) measurements were performed. Ciliary body parameters including maximum ciliary body thickness (CBTmax), ciliary body thickness at point of the scleral spur (CBT0) and 1000 μm from the scleral spur (CBT1000), anterior placement of ciliary body (APCB), and trabecular-ciliary process angle (TCA), as well as biometric measurements, were measured.nnnRESULTSnAverage CBTmax was 0.894 ± 0.114, 0.967 ± 0.110, and 1.053 ± 0.103 mm in eyes with APAC, their fellow eyes, and normal eyes, respectively. Average CBT1000 was 0.616 ± 0.111, 0.631 ± 0.088, and 0.842 ± 0.118 mm, respectively. Average TCA was 48.10 ± 13.26°, 50.60 ± 9.08°, and 87.11 ± 20.71°, respectively. CBTmax and CBT0 were thinner in eyes with APAC compared with their fellow eyes (P = 0.002, P < 0.001). In addition, CBTmax, CBT1000, and TCA were smaller whereas APCB was larger in the fellow eyes of APAC patients compared with normal eyes (P = 0.002, P < 0.001, P < 0.001, P < 0.001). The anterior chamber depth (ACD) was smaller whereas lens thickness (LT) was larger in eyes with APAC compared with their fellow eyes (P < 0.001, P = 0.036). Smaller ACD and axial length and larger LT and lens vault were found in the fellow eyes of APAC patients compared with normal eyes (P < 0.001, P < 0.001, P = 0.015, P = 0.001).nnnCONCLUSIONSnCiliary bodies were thinner and more anteriorly rotated in eyes with APAC as well as in their fellow eyes. Further studies are needed to elucidate the relationship between ciliary body parameters and mechanism of APAC.

Comparison of ocular biometry between eyes with chronic primary angle-closure glaucoma and their fellow eyes with primary angle-closure or primary angle-closure suspect.

Purpose:To compare the eye with chronic primary angle-closure glaucoma (CPACG) with its fellow eye without glaucoma damage and to determine the biometric differences that may predispose to development of CPACG. Methods:Consecutive patients diagnosed with CPACG in 1 eye and primary angle-closure (PAC)/primary angle-closure suspected (PACS) in the fellow eye were recruited. The biometric parameters of both the eyes were measured by A-scan ultrasonic biometry and ultrasound biomicroscopy. Comparisons of visual function, baseline intraocular pressure (IOP), and the biometric measurements were made. Results:Forty-one patients were recruited. Eyes with CPACG had worse visual function, higher baseline IOP, and larger cup-to-disc ratio than their fellow eyes with PAC/PACS (P<0.001). Eyes with CPACG had shallower anterior chamber depths, smaller anterior chamber angles, thinner irises, and longer iris-ciliary process distances than their fellow eyes with PAC/PACS (P<0.05). There were no significant differences in terms of lens thicknesses, axial lengths, lens vault, and trabecular-ciliary process distances. Conclusions:Lens thickness, lens location, and axial length do not appear to play a significant role in the progression from PAC/PACS to CPACG. A thin and anterior iris bowing may be related to the progression from PAC/PACS to CPACG.

A Novel Method for Measuring Anterior Segment Area of the Eye on Ultrasound Biomicroscopic Images Using Photoshop

Purpose To describe a novel method for quantitative measurement of area parameters in ocular anterior segment ultrasound biomicroscopy (UBM) images using Photoshop software and to assess its intraobserver and interobserver reproducibility. Methods Twenty healthy volunteers with wide angles and twenty patients with narrow or closed angles were consecutively recruited. UBM images were obtained and analyzed using Photoshop software by two physicians with different-level training on two occasions. Borders of anterior segment structures including cornea, iris, lens, and zonules in the UBM image were semi-automatically defined by the Magnetic Lasso Tool in the Photoshop software according to the pixel contrast and modified by the observers. Anterior chamber area (ACA), posterior chamber area (PCA), iris cross-section area (ICA) and angle recess area (ARA) were drawn and measured. The intraobserver and interobserver reproducibilities of the anterior segment area parameters and scleral spur location were assessed by limits of agreement, coefficient of variation (CV), and intraclass correlation coefficient (ICC). Results All of the parameters were successfully measured by Photoshop. The intraobserver and interobserver reproducibilities of ACA, PCA, and ICA were good, with no more than 5% CV and more than 0.95 ICC, while the CVs of ARA were within 20%. The intraobserver and interobserver reproducibilities for defining the spur location were more than 0.97 ICCs. Although the operating times for both observers were less than 3 minutes per image, there was significant difference in the measuring time between two observers with different levels of training (p<0.001). Conclusion Measurements of ocular anterior segment areas on UBM images by Photoshop showed good intraobserver and interobserver reproducibilties. The methodology was easy to adopt and effective in measuring.

Dynamic changes of anterior segment in patients with different stages of primary angle-closure in both eyes and normal subjects

Purpose To compare changes in anterior segment parameters under light and dark (light-to-dark) conditions among eyes with chronic primary angle-closure glaucoma (CPACG), fellow eyes with confirmed or suspect primary angle-closure (PAC or PACS), and age-matched healthy eyes. Methods Consecutive patients with CPACG in one eye and PAC/PACS in the fellow eye, as well as age-matched healthy subjects were recruited. Anterior segment optical coherence tomography measurements were conducted under light and dark conditions, and anterior chamber, lens, and iris parameters compared. Demographic and biometric factors associated with light-to-dark change in iris area were analyzed by linear regression. Results Fifty-seven patients (mean age 59.6±8.9 years) and 30 normal subjects matched for age (60.6±9.3 years) and sex ratio were recruited. In regards to differences under light–to-dark conditions, angle opening distance at 500 μm (AOD500μm) and iris area during light-to-dark transition were smaller in CPACG eyes than fellow PACS/PAC eyes and normal eyes (P<0.017). Pupil diameter change was largest in normal eyes, and larger in PACS/PAC eyes than CPACG eyes (P<0.017). There was an average reduction of 0.145 mm2 in iris area for each millimeter of pupil diameter increase in CPACG eyes, 0.161 mm2 in fellow PAC/PACS eyes, and 0.165 mm2 in normal eyes. Larger iris curvature in the dark and diagnosis of PACG were significantly associated with less light-to-dark iris area changes. Conclusions Dynamic changes in iris parameters with light-to-dark transition differed significantly among CPACG eyes, fellow PAC/PACS eyes, and normal eyes. Greater iris curvature under dark conditions was correlated with reduced light-to-dark change in iris area and pupil diameter, which may contribute to disease progression.