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Purpose: To assess the morphological changes in the anterior segment following laser peripheral iridotomy (LPI) in primary angle?closure disease (PACD) using Sirius Scheimpflug?Placido disk corneal topographer. Methods: This was a prospective observational study. A total of 52 eyes of 27 patients with PACD who underwent LPI were analyzed for iridocorneal angle (ICA), anterior chamber depth (ACD), anterior chamber volume (ACV), horizontal visible iris diameter (HVID), corneal volume (CV), central corneal thickness (CCT), and horizontal anterior chamber diameter (HACD) 1 week following LPI, using Sirius Scheimpflug?Placido disk corneal topographer. Data analysis was done using Statistical Package for the Social Sciences (SPSS) software version 19.0, and paired t?test was used to assess the statistical significance. Results: Laser peripheral iridotomy was performed in 43 eyes with primary angle?closure suspect (PACS), six eyes with primary angle closure (PAC), and three eyes with primary angle?closure glaucoma (PACG). The analysis of the data showed statistically significant changes in anterior segment parameters of ICA, ACD, and ACV. Post?laser increase in ICA from 34.13° ± 2.64° to 34.75° ± 2.84° (P < 0.041), mean ACD increase from 2.21 ± 0.25 to 2.35 ± 0.27 mm (P = 0.01), and mean ACV increase from 98.19 ± 12.13 to 104.15 ± 11.16 mm3 (P = 0.001) were noted. Conclusion: Significantly quantifiable short?term changes in the anterior chamber parameters of ICA, ACD, and AC volume were seen after LPI in patients with PACD on Sirius Scheimpflug?Placido disc corneal topographer.
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@#AIM: To compare the anterior chamber volume and corneal volume using Pentacam in people with early keratoconus, subclinical keratoconus, and healthy subjects.<p>METHODS: This epidemiologic study was performed on 63 patients who were candidates for refractive surgery. We classified our patients into three groups as normal, subclinical keratoconus, and early keratoconus according to the Amsler-Krumeich criteria. We collected demographic information, including age and sex, and obtained a full medical history of the patients. Complete visual examination was performed for all patients. Then, using Pentacam, corneal volume and anterior chamber volume were measured among three groups. <p>RESULTS: Corneal volume in the control group was significantly higher than the subclinical keratoconus and early keratoconus groups(<i>P</i><0.05), but the anterior chamber volume was not significantly different between the groups(<i>P</i>>0.05).<p>CONCLUSION: Measuring the corneal volume can help to distinguish the eyes with subclinical keratoconus and early keratoconus from normal eyes. The chamber volume might not differ remarkably among people with subclinical keratoconus, early keratoconus, and those with normal eyes.
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@#AIM: To observe the effect of sub-bowman keratomileusis(SBK)on the posterior corneal curvature, posterior corneal elevation and anterior chamber parameters.<p>METHODS: Prospective self controlled study. Totally 49 patients(97 eyes)with myopia who had planned for SBK were included in this study, mean posterior corneal curvature, central posterior corneal elevation(PCE), anterior chamber volume(ACV), central and peripheral anterior chamber depth(ACD)were measured by Oculyzer before and 1wk, 1y, 3y after surgery. Repeated measure analysis of variance was adopted for data analysis.<p>RESULTS: There were no significant differences in mean posterior corneal curvature at any time point postoperatively compared with that preoperatively(<i>P</i>>0.05). However, central PCE, ACV and central ACD at 1wk, 1y and 3y postoperatively were all decreased(<i>P</i><0.01). Except for the anterior peripheral ACD at 3y after SBK, other peripheral ACD at any time point postoperatively were all decreased(<i>P</i><0.05).<p>CONCLUSION: The posterior corneal curvature remained stable after SBK, while the central PCE shifted slightly backward and the entire anterior chamber became shallow.
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Objective@#To investigate the changes of anterior chamber profiles after small incision lenticule extraction(SMILE) and analyze the possible influencing factors.@*Methods@#A case observation study was designed.Thirty-one patients(59 eyes) with myopia and myopic astigmatism who underwent SMILE surgery at the Refractive Surgery Center of Tianjin Eye Hospital from April to December 2015 were enrolled and examined preoperatively and at 1 month, 3 and 6 months postoperatively.The anterior chamber profiles, including anterior chamber depth (ACD), anterior chamber volume (ACV) and anterior chamber angle (ACA) were measured using the Pentacam.The correlations between parameters were analyzed and the differences of the parameters at different time points were compared.This study followed the Declaration of Helsinki.This study protocol was approved by Ethic Committee of Tianjin Eye Hospital (No.TJYYLL-2015-20). Written informed consent was obtained from each subject before the operation.@*Results@#Compared with pre-operation, the central corneal thickness (CCT) was significantly decreased at 1 month, 3 and 6 months postoperatively (all at P<0.05). Three months after surgery, the CCT was significantly higher than that at one month after surgery (P<0.001), and no significant change of CCT was found between 3 months and 6 months after surgery (P>0.05). The posterior corneal elevation (PCE) at different time points before and after surgery was significantly different (F=19.249, P<0.001), compared with the preoperation, the PCE at 1 month, 3 and 6 months postoperatively moved slightly backward (all at P<0.05). The preoperative ACD was (3.33±0.25)mm, the preoperative ACV was (217.46±31.55)mm3, and the ACD was (3.31±0.25), (3.30±0.25) and (3.30±0.25)mm, the ACV was (214.71±33.09), (211.14±33.65) and (210.08±32.19)mm3, respectively at 1 month, 3 and 6 months postoperatively, with significant differences at different time points before and after surgery (F=12.477, 12.205; both at P<0.001), compared with the preoperation, the ACD at 1 month, 3 and 6 months postoperatively and ACV at 3 months and 6 months postoperatively were obviously decreased, with a significant difference between them (all at P<0.05). There was a significant positive correlation between ACD and ACV at different time points before and after surgery (r=0.870, 0.893, 0.886, 0.884; all at P<0.001). The preoperative ACD was negatively correlated with CCT (r=-0.286, P<0.05).@*Conclusions@#The ACD is decreased postoperatively, it is basically stable at (3.30±0.25)mm, which satisfies the requirements of the ACD required for implantable collamer lens.And the stable state of ACD is also important for keratoconus detection.
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AIM: To research the correlation factor of the anterior segment values of eyes with different axial lengths.METHODS: In this study, 697 cases 697 eyes were included.According to axial length we divided all the cases into short axial length group, normal axial length group, mild long axial length group, moderate long axial length group and severe long axial length group.The relevant indicators of the anterior segment values of patients in the five groups was comparatively analyzed.RESULTS: In the short axial length group, the anterior chamber volume (ACV) showed a significantly negative correlation with age;anterior chamber depth (ACD) showed a significantly negative correlation with age.In the normal axial length group, the ACV showed a significantly negative correlation with age and a significantly positive correlation with axial length(AXL);the anterior chamber angle (ACA) showed a significantly negative correlation with age and a significantly positive correlation with AXL, and a significantly positive correlation with corneal curvature;the ACD showed a significantly negative correlation with age and a significantly positive correlation with AXL.In the mild long axial length group, the ACV showed a significantly negative correlation with age and a significantly positive correlation with AXL, and a significantly negative correlation with corneal curvature;the ACA showed a significantly negative correlation with age and a significantly positive correlation with AXL, and a significantly positive correlation with corneal curvature;the ACD showed a significantly negative correlation with age and a significantly positive correlation with AXL.In the moderate long axial length group, the ACV showed a significantly negative correlation with age;the ACA showed a significantly positive correlation with AXL;the ACD showed a significantly positive correlation with AXL.In the severe long axial length group, the ACV showed a significantly negative correlation with age.There were no significant differences on ACV, ACA and ACD among mild long axial length group, moderate long axial length group and severe long axial length group (P>0.05), while the difference between other groups was significant (P<0.05).CONCLUSION: There has a correlation between the anterior chamber values (ACV, ACA, ACD) age and AXL for eyes which AXL were 22-27mm, while the correlation would disappear as the AXL became shorter or longer.There was a significant growth trend of anterior chamber values for eyes with AXL <27mm.
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Objective To observe the effect of postoperative central vault on the anterior chamber after implantation of im-plantable contact lens V4c .Methods To carry out a retrospective study of 56 eyes with implantable contact lens V4c implantation in Chongqing Bright Eye Hospital from November 2 ,2014 to February 5 ,2015 ,examined anterior chamber angle before surgery ,the anterior chamber angular width (ACA) and anterior chamber volume (ACV) were measured by pentacam .the postoperative central vault and ACA and ACV during the first and third and sixth months after surgery were measured ,the pigment grade in anterior chamber after operation were recorded .The change of ACA and ACV of the 56 eyes was correlation analyzed .Results At first month after surgery ,the postoperative central vault was 250 ~ 765 μm ,the reduced amount of ACA was (13 .67 ± 1 .67)° ,the re-duced amount of ACV was (94 .23 ± 17 .02)mm3 .At the third month ,the postoperative central vault of the 55 eyes was 239 ~ 761μm ,the reduced amount of ACA was (13 .70 ± 1 .68)° ,The reduced amount of ACV was (93 .6 ± 17 .48)mm3 .At the sixth month , the postoperative central vault of the 51 eyes was 246 ~ 761 μm ,the reduced amount of ACA was (13 .60 ± 1 .69)° ,the reduced a-mount of ACV was(94 .29 ± 17 .80)mm3 .No case of pigment was found for grade Ⅱ .The statistical comparison of the amount of ACV and ACA decreased in different postoperative central vaults showed that the difference was statistically significant ,there were statistically significant differences in the amount of ACV and ACA between different central postoperative central vault(P< 0 .05) . Conclusion Anterior chamber angle was narrowed and anterior chamber volume decreased in the posterior chamber intraocular lensimplant-ation after implantable contact lens V4c implantation ,the postoperative central vault is related to the change of anterior chamber angle and ACV .Appropriate postoperative central vault has positive clinical significance for keeping anterior chamber angle open .
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?AlM: To analyze the quantitative changes of anterior segment by Pentacam anterior segment system and to evaluate the safety and effectiveness after implantable collamer lens ( lCL) implantation for high myopia. ?METHODS:Twenty- one patients with 39 eyes were implanted lCL in our hospital from September 2011 to February 2013. The follow-up was 6 ~ 12mo. Central anterior chamber depth ( ACD ) , anterior chamber angle ( ACA) , anterior chamber volume ( ACV) were measured by Pentacam preoperatively, 1wk, 1 and 6mo postoperatively. The distance between crystal lens and lOL ( lCL- vault ) were measured at 1wk, 1 and 6mo postoperatively. Preoperative uncollected visual activity ( pre - UCVA ) , best corrected visual acuity ( BCVA ) , postoperative uncorrected visual acuity ( post-UCVA) and intraocular pressure ( lOP) were recorded. The paired t-test was used to access the data preoperatively and postoperatively in the statistical way by using SPSS 18. 0 statistical software. ? RESULTS: Preoperatively, at 1wk, 1 and 6mo postoperatively, ACD were 3. 27±0. 22, 3. 02±0. 33, 2. 98±0. 31, and 2. 98±0. 32mm. ACA were (40. 39±5. 40)o, (26. 70±4. 47)o, (26. 96±4. 48)o, and (26. 95±4. 45)o. ACV were 207. 74±25. 43, 122. 87±17. 58, 128. 05±17. 84, and 128. 64±17. 50mm3 , respectively. There were statistically significant differences between preoperative and postoperative data in ACD, ACA, ACV (P ?CONCLUSlON:ACD, ACA, ACV by Pentacam anterior segment system are found to be decreased after the operation, but there is still a relative safe distance between lOL and the crystal len. lCL implantation is a safe, efficacy method in correcting high myopia, but the long-term effects will require further observation.
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PURPOSE: To investigate changes in corneal keratometry and the anterior chamber in intermittent exotropia after lateral rectus recession using Pentacam. METHODS: Corneal keratometry, anterior chamber depth, and anterior chamber volumes were evaluated preoperatively and at 1 week, 1 month, and 2 months postoperatively using Pentacam in 20 patients (40 eyes) who underwent lateral rectus muscle recession. The IOP was measured before and after lateral rectus muscle detachment during the surgery. According to the change in IOP, the patients were divided into 2 groups; Group 1 (DeltaIOP or = 3 mm Hg), and the results of the 2 groups were compared. RESULTS: The horizontal keratometry and anterior chamber volumes significantly decreased 1 week postoperatively, although there were no significant differences in vertical keratometry, mean keratometry, or anterior chamber depth. Additionally, there were no significant changes in any measurement parameters at 1 month or 2 months postoperatively. In Group 2, horizontal keratometry, mean keratometry, and anterior chamber volumes showed significant reduction compared with those in Group 1. There were no significant differences between the 2 groups at 1 month postoperatively. CONCLUSIONS: Postoperative corneal keratometry and anterior chamber volumes did not change significantly compared to preoperative values in intermittent exotropia after performing lateral rectus muscle recession. However, the higher the ocular muscle tension, the greater were the changes in corneal astigmatism and anterior volumes.