Lamina Cribrosa Depth Research Articles

Differentiation of Nonarteritic Anterior Ischemic Optic Neuropathy from Normal Tension Glaucoma by Comparison of the Lamina Cribrosa.

PurposeTo compare lamina cribrosa (LC) morphology between eyes with nonarteritic anterior ischemic optic neuropathy (NAION) and eyes with normal tension glaucoma (NTG) in the Korean population.MethodsThis retrospective study included 48 eyes with NAION, 48 eyes with NTG, and 48 healthy control eyes matched by age, intraocular pressure, axial length, and optic disc area. Eyes with NAION and NTG were also matched by retinal nerve fiber layer (RNFL) thickness in the affected sector. Optic nerve heads were scanned using enhanced depth imaging spectral-domain optical coherence tomography. LC depth (LCD) and the LC curvature index (LCCI) were measured at seven locations spaced equidistantly across the vertical optic disc diameter. LCD and the LCCI were compared in the three groups.ResultsRNFL thicknesses of the matched affected sectors did not differ between the NAION and NTG groups (P = 0.347). LCD and the LCCI were significantly larger in the NTG group than in the NAION and healthy control groups at all seven planes (P < 0.001 each), but were comparable in the NAION and healthy control groups. The LCCI was larger in the affected than in the unaffected sector of NTG eyes (P = 0.010) but did not differ in NAION eyes (P = 1.000). LCD did not differ between affected and unaffected sectors in either NAION (P = 0.600) or NTG (P = 0.098) eyes.ConclusionsLC morphology differed in eyes with NAION and NTG, despite a similar degree of RNFL damage. Evaluation of LC morphology may help to understand the distinctive pathophysiology of NAION and to differentiate NAION from NTG eyes.

Lamina Cribrosa Moves Anteriorly After Trabeculectomy in Myopic Eyes.

PurposeThe purpose of this study was to investigate changes in lamina cribrosa (LC) depth after trabeculectomy in myopic eyes using enhanced depth imaging (EDI) spectral-domain optical coherence tomography (SD-OCT).MethodsSerial horizontal B-scans of the optic nerve head of 41 myopic eyes with primary open-angle glaucoma (POAG) were obtained before and 3 months after trabeculectomy using EDI SD-OCT. LC depth, defined as the distance from the opening plane of Bruch's membrane to the level of the anterior LC surface, was measured before and 3 months after trabeculectomy at 7 locations spaced equidistantly across the vertical optic disc diameter on B-scan images. The mean of the measurements at these seven planes was defined as the average LC depth. Factors associated with changes in LC depth were identified by linear regression.ResultsIntraocular pressure (IOP) decreased from 26.3 ± 9.3 millimeters of mercury (mm Hg) preoperatively to 10.6 ± 3.5 mm Hg 3 months after trabeculectomy. LC depth was significantly lower 3 months after trabeculectomy than preoperatively (P < 0.001, all planes). The magnitude of LC depth reduction was significantly associated with younger age, higher preoperative LC depth, and greater magnitude of IOP reduction (all P ≤ 0.016).ConclusionsLC depth reduction was observed after trabeculectomy in myopic eyes. The degree of LC depth reduction was not related to the degree of myopia.

Evaluation of retina nerve fiber layer, ganglion cell-inner plexiform layer and lamina cribrosa in clinically unilateral exfoliative glaucoma.

To compare retinal nerve fiber layer (RNFL), ganglion cell-inner plexiform layer (GC-IPL), the lamina cribrosa depth (LCD) and thickness (LCT) in unilateral exfoliative glaucoma (EXG) patients with their fellow eyes without exfoliation and control eyes. This cross-sectional prospective single-center study consisted of 64 eyes of 32 patients with unilateral EXG and 35 eyes of controls. All subjects were examined with spectral domain optical coherence tomography for the RNFL and GC-IPL measurements. The LCD and LCT measurements were also obtained. The RNFL measurements at all quadrants were statistically thinner in EXG eyes than those in their eyes without EXG and control eyes (p < 0.001 for average, superior, temporal and inferior; p = 0.004 for nasal). The EXG group had deeper LCD than their eyes without EXG and control eyes (p < 0.001, for both). The fellow eyes of EXG group had also deeper LCD than control eyes, with no statistical significance (p = 0.058). The mean LCT was thinner in EXG eyes compared to those in the eyes without EXG and control eyes (p < 0.001, for both). The eyes without EXG and control eyes had similar LCT (p = 0.293). Recent developments in imaging technology give the clinician detailed structural information about optic nerve head and retina such as GC-IPL, LCD and LCT. In addition to follow-up of RNFL changes, these new parameters may be useful in recognizing progression in EXG patients.

Determinants of lamina cribrosa depth in healthy Asian eyes: the Singapore Epidemiology Eye Study

AimTo investigate the determinants of lamina cribrosa depth (LCD) in healthy eyes of Chinese and Indian Singaporean adults.MethodsThe optic nerve head (ONH) of the right eye of 1396 subjects (628...

Evaluation of Posterior Ocular Structures in Patients with Isolated Iris Coloboma.

Objectives:To measure lamina cribrosa thickness (LCT), lamina cribrosa depth (LCD) and subfoveal choroidal thickness (SFCT) by imaging posterior ocular structures in pediatric cases with isolated unilateral iris coloboma and to investigate the differences as compared with healthy contralateral eyes of these cases (fellow eyes) and healthy control eyes.Methods:This cross-sectional, comparative prospective study included seven children (age range, 9-17 years) with unilateral isolated iris coloboma. The healthy contralateral eyes of these cases formed the fellow group. An age-matched (age range 8-17 years) control group (n=9), including children with both eyes having either normal or corrected-to-normal visual acuity, was formed. A detailed ophthalmic examination was performed. The posterior ocular segments were evaluated using spectral domain-optical coherence tomography (SD-OCT) with enhanced depth imaging (EDI) technique.Results:The SFCT was 372.0±48.8 µm, 375.3±44.0 µm, and 386.5±71.8 µm, respectively, and the LCD was 362.4±68.3 µm, 354.4±47.1 µm, and 350.7±38.1 µm, respectively, in the coloboma, fellow, and control eyes. There was no difference between the groups regarding SFCT and LCD. The mean LCT was significantly thinner in the coloboma eyes (200.2±9.5 µm) than in the fellow (238.8±26.7 µm; p=0.023) and control eyes (240.0±12.9 µm; p<0.001). The LCT showed no significant correlation with age, axial length or spherical equivalent.Conclusion:Better visual prognosis is expected in isolated iris coloboma. However, detailed examinations using new technologies, such as SD-OCT, may reveal some structural changes. Longitudinal studies are required to understand if a thinner LCT in coloboma eyes is associated with any future problems.

New morphometric criteria in the study of pathogenesis of normal-tension glaucoma

Studying the factors that contribute to the disturbance of transmembrane pressure gradient is a topical task in the research of pathogenesis of normal-tension glaucoma (NTG). To measure and compare the thickness and depth of lamina cribrosa (LCT and LCD), as well as optic nerve subarachnoid space width (ONSASW) in patients with NTG and healthy individuals. The first group included 12 patients (23 eyes) aged from 58 to 74 years (average age 66.8±3.2 years) with NTG who all had normal intraocular pressure and arterial hypotension. The second (control) group consisted of 11 healthy individuals (22 eyes) aged from 51 to 69 years (average age 56.2±4.2 years). All patients underwent structural and functional assessment of the optic nerve head using OCT RTVue-100 (Optovue, USA), as well as Humphrey Visual Field Analyzer (HFA II 745i, Germany-USA) and our modification of Frequency Doubling Technology perimetry. In all subjects the central corneal thickness (CCT) was measured by Pentacam HR (Oculus, Germany), the LCT and LCD were measured by EDI (Enhanced Depth Imaging) mode of Topcon 3D OCT 2000 (Japan). To measure the ONSASW we used a cross-sectional image of the optic nerve taken 3 mm behind the eyeball with Magnetic Resonance Imaging (Siemens Magnetom Symphony 1.5 T, Germany). Statistically significant difference was found between the 1st and 2nd groups in the average LCT (217.60±36.92 and 345.86±33.29 μm respectively; p=0.0000), LCD (435.00±86.31 and 367.31±87.00 μm, respectively; p=0.014) and ONSASW (1.27±0.13 and 1.44±0.19 mm respectively; p=0.004); the difference wasn't significant in the average CCT (543.26±31.52 and 557.50±24.92 μm respectively; p=0.11). Patients with NTG had significantly higher value of the LCD with significantly lower values of the LCT and ONSASW compared with healthy individuals, which confirms the importance of these morphometric criteria in the study of NTG pathogenesis.

Association of lamina cribrosa morphometry with retinal nerve fiber layer loss and visual field defects in primary open angle glaucoma.

Objectives:To calculate the anterior lamina cribrosa depth (ALCD) and lamina cribrosa thickness (LCT) in primary open angle glaucoma (POAG) patients and controls and to correlate lamina cribrosa (LC) parameters to retinal nerve fiber layer thickness (RNFLT) and visual field (VF) defects.Methods:The study was conducted from November 2018 to March 2019. A total of 60 correspondents (30 cases and 30 controls) were assessed for general ophthalmological investigations including intraocular pressure (IOP), axial length AXL, ophthalmoscopy, visual field (VF) testing and spectral domain ocular computed tomography (SDOCT).Results:The mean age of subjects was 62 years (Cases 67.30±1.2, controls 57.32±1.1) with more male participants. Intraocular pressure [IOP (19.85 ±1.4)], AXL (22.85 ± 1.6), VF defects (8.30 ± 4.5), RNFLT (72.58 ± 13.2) and LCT (162.51 ± 64.62) were statistically significant in POAG patients as compared to the controls.Conclusion:A thinner LC in POAG correlated significantly with the RNFLT and VF defects. LC anatomical parameters can be estimated with precision using SDOCT with enhanced depth imaging (EDI).

In Vivo anterior Optic Nerve Head changes as a function of Visual Field loss in Glaucoma

AbstractPurposeTo correlate regional measures of prelamina (preL) depth and thickness, anterior lamina cribrosa (LC) depth and nerve fibre layer (NFL) thicknesses with change in visual field sensitivity in primary open angle glaucoma, using enhanced depth imaging optical coherence tomography (OCT).MethodsThree‐dimensional image datasets were acquired as 20° scans centred on the optic nerve head (ONH) of glaucoma (n=111) and control (n=39) eyes, using a custom built OCT at 1040nm (spectral bandwidth 70nm). ONH measurements of regional (superior [S], inferior [I], nasal [N], temporal [T], and central [C]) preL and anterior LC depth were performed using Bruch’s membrane opening as a reference plane. PreL thickness was calculated from these surface measures. Border (above BMO) and peripapillary (pp) NFL were also measured. Intraclass correlation coefficients (ICC) were used to determine intra‐session repeatability.ResultsPreL depth (S: r=0.339, I: r=0.363, and N: r=0.317; p&lt;0.001, T: r=0.219, p=0.007, central: r=0.202, p=0.013) and anterior LC depth (S: r=0.232, p=0.006, I: r=0.229, p=0.006, N: r=0.246, p=0.009, T: r=0.169, p=0.04, central: r=0.226, p=0.006) significantly increased with increasing VF loss in all ONH regions. PreL thickness significantly decreased with increasing VF loss in all ONH regions, (S: r=‐0.295 and I: r=‐0.346; p&lt;0.001, N: r=‐0.218, p=0.026, temporal: r=‐0.177, p=0.031), except for the centre (r=‐0.106, p=0.199). ICCs &gt;0.9 were calculated for all ONH measures and intra‐session differences in the ONH parameters were not identified within triplicate image datasets (p&gt;0.05). BNFL and ppNFL thicknesses significantly decreased with VF loss (p&lt;0.001).ConclusionsSignificant correlations were found between preL depth and thickness, and anterior LC depth with VF function, indicating that these quantitative (and repeatable) measures are useful in monitoring glaucomatous optic neuropathy.

Thickness of the Lamina Cribrosa, Retinal-Nerve Fiber Layer, and Peripapillary Choroid in Patients with Branch Retinal Vein Occlusion

Purpose: To compare the thickness of the lamina cribrosa (LC), retinal-nerve fiber layer (RNFL), and peripapillary choroid (PC) in patients with unilateral branch retinal-vein occlusion (BRVO) and healthy individuals. Methods: The 70 eyes of 35 patients with unilateral BRVO, grouped as either affected or unaffected, and 38 right eyes of 38 healthy individuals were examined for LC, RNFL, PC thickness, and LC depth with spectral-domain optical coherence tomography. Results: The unaffected eyes of patients with BRVO had a significantly thinner RNFL on average and in the inferior quadrant than the eyes of healthy controls. Mean LC thickness in BRVO-affected and BRVO-unaffected eyes was significantly thinner than in controls, and mean LC depth was significantly deeper as well. The average, superior, and inferior PC thickness in both BRVO-affected and BRVO-unaffected eyes and nasal PC thickness in the BRVO-affected eyes were significantly thinner than in the eyes of controls. Conclusion: Thinner LCs and PCs in both eyes of patients with unilateral BRVO and thinner RNFLs in BRVO-unaffected eyes than in the eyes of healthy controls suggest that BRVO and glaucoma have underlying pathological mechanisms and risk factors in common that lead to their development.

Şizofreni Hastalarında Gözün Arka Segment Yapılarının Değerlendirilmesi

Purpose: We aimed to evaluate the effects of schizophrenia on posterior ocular structures including the retinal nerve fiber layer (RNFL), central macular thickness (CMT), choroidal thickness (CT) and lamina cribrosa (LC) measurements.Methods: A total of 35 patients with schizophrenia and 35 healthy individuals were enrolled. Only the right eye of each participant was tested. RNFL thickness in all quadrants, CT, CMT, LC thickness, and LC depth (LCD) measurements were performed using Fourier domain optic coherence tomography (OCT), and each variable was compared between groups.Results: The mean age and sex distributions were similar between groups (p=0.528 and p=0.299, respectively). The average, superior, inferior, nasal, and temporal RNFL thicknesses were significantly lower in schizophrenia patients than in controls (p&amp;lt;0.001, p&amp;lt;0.001, p=0.001, p=0.002 and p&amp;lt;0.001, respectively). The mean subfoveal and perifoveal CT were not significantly different between the groups (subfoveal; p=0.676, 1.5 mm nasal; p=0.632, 3 mm nasal; p=1.000, 1.5 mm temporal; p=0.811, 3 mm temporal; p=0.145). The mean CMT was similar among the groups (p=0.678). LC thickness and LCD were not statistically significant between groups (p=0.816 and p=0.161).Conclusions: We demonstrated that RNFL thicknesses in all quadrants were significantly lower in schizophrenia patients than in control subjects. However, there were no significant differences in the CMT, perifoveal and subfoveal CT, LC thickness, and LCD between the groups. These results suggest that OCT can be used to image neuronal loss by evaluating the RNFL in patients with schizophrenia. Keywords: Schizophrenia; retinal nerve fiber layer; choroidal thickness; lamina cribrosa thickness; macular thickness

Relationship between corneal deformation amplitude and optic nerve head structure in primary open-angle glaucoma.

The purpose of the study was to investigate the relationship between corneal deformation amplitude (DA), which is the amount of corneal displacement at highest degree of concavity measured by Corvis Scheimpflug Technology (ST), and various optic nerve head parameters in patients with primary open-angle glaucoma (POAG).Fifty-eight POAG patients were included in this observational study. For each patient, DA with Corvis ST, color optic disc photography, and optic nerve head imaging by enhanced depth imaging with a Heidelberg spectralis optical coherence tomography (OCT), Cirrus OCT, and Heidelberg retina tomograph (HRT) were obtained. Pearson correlation was used to analyze the relationship between DA and optic nerve head parameters before and after adjusting for age, intraocular pressure, central corneal thickness, and axial length.Corneal DA was negatively associated with lamina cribrosa (LC) depth (r = −0.390, P = .003) after adjusting for confounders. It showed positive relationship with parapapillary atrophy (PPA) area (r = 0.321, P = .046). In addition, the corneal DA was negatively correlated with cup volume (r = −0.351, P = .017) and mean cup depth (r = −0.409, P = .005) measured by HRT.Corneal DA is related with optic nerve head parameters in patients with POAG. Patients with lower corneal DA showed greater LC depth, greater cup area, deeper cup, and smaller PPA than those with higher corneal DA.

Evaluation of the lamina cribrosa thickness and depth in patients with migraine.

The aim of the study was to evaluate the lamina cribrosa (LC) thickness, LC depth, and retinal nerve fiber layer (RNFL) thickness, in migraine patients with and without aura, by using optical coherence tomography (OCT). This single-center, case-control study included 27 migraine with aura (Group I), 35 migraine patients without aura (Group II), and 35 healthy controls (Group III). In only the right eyes of participants, RNFL thickness in all quadrants was analyzed via OCT, whereas LC thickness and depth were measured by enhanced depth imaging OCT. The mean age and sex distributions did not differ significantly across the groups (p = 0.460 and p = 0.941). The RNFL thickness was significantly lower in Group I (average and superotemporal, superonasal, and inferotemporal quadrants) and Group II (average and superotemporal and superonasal quadrants) when compared with Group III. Disease duration was significantly correlated with RNFL thickness on average and in all quadrants except in the superonasal quadrant in Groups I and II. Patients in Groups I and II had significantly thinner LC thicknesses and deeper LC depth than healthy participants in Group III. The LC and RNFL thicknesses were thinner and the LC depth was deeper in migraine patients with or without aura than in healthy individuals, and disease duration correlated significantly with RNFL thickness. Both results suggest that migraine patients are at risk of developing glaucoma.

Variation of Peripapillary Scleral Shape With Age.

PurposeTo define the shape of the anterior surface of the peripapillary sclera (PPS) and evaluate its relationship with age and ocular determinants in a population-based Chinese cohort.MethodsThe optic nerve heads of 619 healthy Chinese subjects were imaged with spectral-domain optical coherence tomography. To assess the shape of the PPS/Bruch's membrane (BM), we measured the angle between a line parallel to the nasal anterior PPS/BM boundary and one parallel to the temporal side. A negative value indicated that the PPS/BM followed an inverted v-shaped configuration (peak pointing toward the vitreous), whereas a positive value indicated that it followed a v-shaped configuration (peak pointing toward the orbital tissues). A linear regression model was used to evaluate the relationship between the PPS angle and other ocular parameters.ResultsThe mean PPS angle was 3.68° ± 6.73° and the BM angle was 9.69° ± 5.05°. The PPS angle increased on average by 0.233 deg/y. A v-shaped PPS was significantly associated with age (β = 0.087, P = 0.004), peripapillary choroidal thickness (β = −0.479, P < 0.001), lamina cribrosa depth (β = 0.307, P < 0.001), and BM angle (β = 0.487, P < 0.001) after adjusting for best corrected visual acuity, central corneal thickness, and axial length.ConclusionsThe anterior surface of PPS of an elderly adult population had a v-shaped configuration and was more pronounced with increasing age, thin peripapillary choroid, and a deep cup. Such a change in shape with age could have an impact on the biomechanical environment of the optic nerve head.

Lamina Cribrosa Depth and Shape in Glaucoma Suspects. Comparison to Glaucoma Patients and Healthy Controls

ABSTRACT Purpose To evaluate the lamina cribrosa depth and shape parameters in glaucoma suspects compared to glaucoma patients and healthy controls. Materials and Methods A total of 325 subjects (120 with primary open-angle glaucoma, 103 glaucoma suspects and 102 healthy controls) were included. Serial horizontal B-scan images of optic nerve head were obtained using enhanced depth imaging of the optical coherence tomography. For each of the 325 subjects, lamina cribrosa position was measured manually in 16 horizontal B-scans, hence 5200 scans in total were analyzed. In particular, lamina cribrosa depth (LCD), lamina cribrosa deflection depth (LCDD), lamina cribrosa shape index (LCSI), and its horizontal equivalent (LCSIH) were estimated. Along lamina cribrosa parameterization, intraocular pressure, visual field, central retinal thickness, retinal nerve fiber layer thickness, and disc and neuroretinal rim areas were also measured. Results LCD was statistically significant different (P < .001) in glaucoma patients when compared to glaucoma suspects and heathy controls (603 ± 172 μm versus 554 ± 114 μm and 531 ± 115 μm, respectively). Similarly, LCDD was statistically significant different (P < .001) in glaucoma patients when compared to glaucoma suspects and heathy controls (250 ± 78 μm versus 213 ± 54 μm and 211 ± 58 μm, respectively). No statistically significant differences were found in LCSI (P = .957). However, LCSIH showed statistically significant differences between healthy controls and glaucoma suspects (P = .003) and between healthy controls and glaucoma patients (P = .006). Conclusions The deformation of LC in glaucoma suspects, in terms of LCSIH, was not statistically different from that of glaucoma patients. LCD does not have the potential to discriminate glaucoma suspects from healthy controls.

Evaluation of lamina cribrosa in angioid streaks using spectral-domain optical coherence tomography enhanced depth imaging

To investigate retinal nerve fiber layer (RNFL) thickness, anterior lamina cribrosa depth (ALD) and laminar thickness (LT) in eyes with angioid streaks (AS) in comparison with healthy eyes. Patients with AS (n=32 eyes) and age-matched healthy subjects (n=42 eyes) underwent enhanced depth imaging with spectral domain optical coherence tomography of the optic nerve head. RNFL thickness was obtained automatically by using the Heidelberg software. The ALD was defined as the vertical distance between the Bruch's membrane openings as reference plane and the anterior border of the lamina cribrosa. The LT was measured as the distance between the anterior and posterior borders of the lamina cribrosa. RNFL thickness, ALD and LT were compared between the AS and healthy eyes adjusting for axial length. The mean age was 51.7±8.0 years for AS patients and 53.8±10.2 years for control subjects (P=0.34). The mean RNFL thickness was 88.6±17.6μm in AS eyes and 102.1±8.3μm in control eyes; the difference between the groups was significantly significant. ALD was 350.9±70.8μm in AS eyes and 432.5±82.1μm in control eyes, while LT was 166.3±41.0μm in AS eyes and 241.3±43.2μm in control eyes. ALD and LT were also significantly thinner in AS eyes than control eyes (P=0.003, P<0.001; respectively). Enhanced depth imaging revealed that eyes with AS demonstrate thinner RNFL, ALD and LT compared with normal eyes. Further studies with a larger sample size are needed to understand the relationship between these findings and the morphologic changes and pathogenesis of AS.

Relationship Between Optical Coherence Tomography Angiography Peripapillary Vessel Density and Lamina Cribrosa Depth.

To investigate the global and regional relationship between the pVD assessed by OCT-A and LCD assessed by enhanced depth imaging spectral-domain optical coherence tomography (SD-OCT). A total of 38 eyes of 38 healthy subjects and 38 eyes of 38 glaucoma patients were included. Peripapillary microvasculature and lamina cribrosa were imaged by OCT-A and enhanced depth imaging SD-OCT, respectively. The pVD and LCD were measured at temporal, superotemporal, superonasal, nasal, inferonasal, and inferotemporal sectors. Global and regional correlations between pVD and LCD were evaluated in all subjects. The pVD (59.0±2.6 vs. 54.4±5.4%) and LCD (318.5±76.4 vs. 404.6±92.5 μm) were significantly different between healthy and glaucoma subjects. The average pVD assessed by OCT-A was not significantly correlated with average LCD assessed by SD-OCT (r=-0.160, P=0.167). Regional correlation between pVD and LCD was statistically significant only in the inferotemporal sector (r=-0.301 and P=0.008). In the linear regression analysis, reduced pVD was independently associated with decreased visual field mean deviation and peripapillary retinal nerve fiber layer thickness but not with increased LCD. Global and regional correlations between pVD and LCD were poor except for the inferotemporal sector. This finding suggests that peripapillary microvascular impairment may not result directly from posterior lamina cribrosa displacement.

Combination of Enhanced Depth Imaging Optical Coherence Tomography and Fundus Images for Glaucoma Screening.

Glaucoma is an eye disease that damages the optic nerve and can lead to irreversible loss of peripheral vision gradually and even blindness without treatment. Thus, diagnosing glaucoma in the early stage is essential for treatment. In this paper, an automatic method for early glaucoma screening is proposed. The proposed method combines structural parameters and textural features extracted from enhanced depth imaging optical coherence tomography (EDI-OCT) images and fundus images. The method first segments anterior the lamina cribrosa surface (ALCS) based on region-aware strategy and residual U-Net and then extracts structural features of the lamina cribrosa, such as lamina cribrosa depth and deformation of lamina cribrosa. In fundus images, scanning lines based on disc center and brightness reduction are used for optic disc segmentation and brightness compensation is utilized for segmenting the optic cup. Afterward, the cup-to-disc ratio (CDR) and textural features are extracted from fundus images. Hybrid features are used for training and classification to screen glaucoma by gcForest in the early stage. The proposed method has given exceptional results with 96.88% accuracy and 91.67% sensitivity.

Age-Dependent Variation of Lamina Cribrosa Displacement During the Standardized Valsalva Maneuver

Based on biomechanical theory, lamina cribrosa (LC) displacement, the key component of progressive glaucomatous change, is presumed to be dependent on intraocular pressure (IOP) as well as tissue stiffness of LC. In the performance of the Valsalva maneuver, both IOP and cerebrospinal fluid pressure can increase. The present study investigated the age-dependent variation of LC displacement during the standardized Valsalva maneuver in healthy subjects. Sixty-three (63) eyes (age range: 20–76 years) were prospectively underwent IOP measurement and Cirrus HD-OCT optic disc scans before and during the standardized Valsalva maneuver. During the standardized Valsalva maneuver, the IOP significantly increased from 13.2 ± 2.9 mmHg to 18.6 ± 5.2 mmHg (P < 0.001). The maximal LC depth significantly decreased in the younger age groups (age: 20 s to 40 s) but not in the older age groups (age: over 50). The BMO distance did not change significantly. Younger age (P = 0.009), a smaller increase of IOP during the Valsalva maneuver (P = 0.002), and greater baseline maximal LC depth (P = 0.013) were associated with more anterior displacement of the LC during the standardized Valsalva maneuver. Taken together, age as well as translaminar pressure dynamics seems to play a crucial role in LC biomechanics.

Changes in the Anterior Lamina Cribrosa Morphology with Glaucoma Severity

This study was designed to evaluate if primary open angle glaucoma (POAG) and its severity are associated with the shape of the lamina cribrosa (LC) as measured by a global shape index (LC-GSI), or other indices of LC curvature or depth. Optical coherence tomography (OCT) scans of the optic nerve head (OHN) were obtained from subjects with POAG (n = 99) and non-glaucomatous controls (n = 76). ONH structures were delineated, the anterior LC morphology reconstructed in 3D, and the LC-GSI calculated (more negative values denote greater posterior concavity). Anterior LC depth and 2D-curvature were also measured. Severity of glaucoma was defined by the extent of visual field loss, based on the Hodapp-Parrish-Anderson grading. Linear regression analyses compared LC characteristics between controls, mild-moderate, and advanced POAG groups. After adjusting for age, gender, ethnicity, intraocular pressure, axial length and corneal curvature, the LC-GSI was most negative in the advanced POAG group (mean [standard error] = −0.34 [0.05]), followed by the mild-moderate POAG group (−0.31 [0.02]) and then controls (−0.23 [0.02], PTrend = 0.01). There was also a significant trend of increasing LC depth and greater LC horizontal curvature with increasing severity of glaucoma (PTrend = 0.04 and 0.02, respectively). Therefore, with more severe glaucoma, the LC-GSI was increasingly more negative, and the anterior LC depth and curvature greater. These observations collectively correspond to greater cupping of the ONH at the level of the LC. As the LC-GSI describes the 3D anterior LC morphology, its potential usage may be complementary to existing ONH parameters measured on OCT.

Comparison of the Lamina Cribrosa Measurements Obtained by Spectral-Domain and Swept-Source Optical Coherence Tomography

ABSTRACT Purpose/Aim of the study The aim of this study was to compare the lamina cribrosa (LC) measurements obtained by Spectral-Domain Optical Coherence Tomography (SD-OCT) and Swept-Source Optical Coherence Tomography (SS-OCT) in the same eye and we also investigate how the differences in measurement will change in the presence of pseudoexfoliation glaucoma (PEG). Materials and Methods A total of 30 patients from one institution have accepted. Detailed medical case histories and clinical examination, optic nerve head imaging using the SD-OCT (Heidelberg Engineering, Heidelberg, Germany) and SS-OCT (Triton; Topcon Medical Systems, Tokyo, Japan) for patients with pseudoexfoliation glaucoma and healthy volunteer. Results Fifty-three eyes of the 30 patients (13 female, 17 male) were included in the study. Twenty-nine of eyes were healthy and 24 of eyes had pseudoexfoliation glaucoma. The mean age was 62 ± 7.3 years (range, 50–86 years). The difference between the mean Bruch’s membrane opening distance measured by SD-OCT (1504.7 ± 154.2 µm) and by SS-OCT (1568.6 ± 193.3 µm) was statistically significant (p = .009). The difference between LC depth and LC thickness measurements between two OCT devices were not statistically significant. There was a negative correlation between the difference of two devices Bruch’s membrane opening distance measurements and the cup/disc ratio (p = .007). Conclusion Generally accepted belief is that lamina cribrosa visibility would be worse in healthy subjects who have thick prelaminar tissues, and better in individuals with glaucoma who had suffered the loss of prelaminar tissue. The difference between Bruch’s membrane opening distance measurements taken with two devices was greater in normal eyes, and this difference was decreasing in glaucomatous eyes in our study. The Lamina Cribrosa measurement values shall not be directly compared between SD-OCT and SS-OCT.