Lamina Cribrosa Reversal after Trabeculectomy and the Rate of Progressive Retinal Nerve Fiber Layer Thinning.

To determine whether the reversal of lamina cribrosa (LC) displacement observed after trabeculectomy is associated with the rate of progressive retinal nerve fiber layer (RNFL) thinning in primary open-angle glaucoma (POAG). Observational case series. Thirty-four patients with POAG who underwent trabeculectomy and were followed up for at least 2.5 years, during which the RNFL thickness was measured by serial spectral-domain (SD) optical coherence tomography (OCT). The participants underwent enhanced depth imaging scanning of the optic nerve using SD OCT before surgery (PREOP), at a 6-month postoperative follow-up (FU1), and at a subsequent follow-up that was performed at least 2.5 years postoperatively (FU2), and serial RNFL thickness was measured at least 5 times during the study period. Preoperative and postoperative LC depths (LCDs) as determined on 7 selected B-scan images from each eye were averaged to produce the mean LCD. The rate of RNFL thinning was determined by linear regression of serial OCT RNFL thickness measurements over time. Factors associated with the rate of OCT RNFL thinning. The intraocular pressure (IOP) decreased from 23.8±7.9 mmHg (mean±standard deviation) to 11.0±4.4 mmHg at FU1 (P<0.001) and subsequently increased to 13.1±5.2 mmHg at an overall follow-up of 3.5±0.8 years (P=0.003). The LCD was reduced from 589.90±148.32 to 508.57±136.28 μm at FU1 (P<0.001). A subsequent slight but nonsignificant increase in the LCD was noted at FU2 (516.48±145.87 μm; P=0.410). A faster rate of RNFL thinning was associated with a shorter follow-up period (P=0.032), higher IOP at PREOP (P=0.011) and FU2 (P=0.014), and a larger increase in LCD from FU1 to FU2 (P<0.001). The changes in LCD between PREOP and FU1 and between PREOP and FU2 were not associated with the rate of RNFL thinning. Eyes with sustained LCD reduction over a long period had a slow rate of progressive RNFL thinning after trabeculectomy. A large LCD reduction in the early postoperative period was not associated with the long-term rate of progression if it was not maintained during subsequent follow-up.

Lee EJ ，Kim TW 《-》

Influence of lamina cribrosa thickness and depth on the rate of progressive retinal nerve fiber layer thinning.

To determine whether lamina cribrosa (LC) depth (LCD) and LC thickness (LCT) are associated with a faster rate of progressive retinal nerve fiber layer (RNFL) thinning in primary open-angle glaucoma (POAG). Prospective, observational study. One hundred ten eyes diagnosed with POAG (n = 110 patients) in which RNFL thickness had been measured by serial spectral-domain (SD) optical coherence tomography (OCT) for at least 2.5 years. The participants underwent enhanced depth imaging volume scanning of the optic nerve, and circumpapillary RNFL thickness measurements were obtained using SD OCT. The participants were followed up regularly with serial RNFL thickness measurements at 6-month or longer intervals. Lamina cribrosa depth was measured at 7 equidistant planes and LCT was measured at 3 locations (superior midperipheral, midhorizontal, and inferior midperipheral). The rate of RNFL thinning was determined by linear regression of serial OCT RNFL thickness measurements over time. Factors associated with the rate of OCT RNFL thinning. A faster rate of RNFL thinning was associated with disc hemorrhage during follow-up (P < 0.001), wider β-zone parapapillary atrophy with Bruch's membrane (P = 0.037), larger global RNFL thickness (P = 0.026), larger LCD (P < 0.001), and smaller LCT (P = 0.002). The association between LCD and the rate of RNFL thinning was explained better using a fractional polynomial model (R(2) = 0.223) than a linear model (R(2) = 0.134; P = 0.010). Davies' test revealed a statistically significant breakpoint for LCD (489.7 μm), above which a faster rate of global RNFL thinning was associated with a larger LCD. A thinner LC and a larger LC displacement had a significant influence on the rate of progressive RNFL thinning.

Lee EJ ，Kim TW ，Kim M ，Kim H ... -  《-》

Comparison between Lamina Cribrosa Depth and Curvature as a Predictor of Progressive Retinal Nerve Fiber Layer Thinning in Primary Open-Angle Glaucoma.

To compare the ability of lamina cribrosa (LC) depth (LCD) and LC curvature to predict the rate of progressive retinal nerve fiber layer (RNFL) thinning in patients with primary open-angle glaucoma (POAG). Observational case series. A total of 114 eyes of 114 patients diagnosed with POAG, in which RNFL thickness had been measured by serial spectral-domain (SD) OCT for at least 2.5 years. The optic nerves of all participants underwent enhanced depth imaging volume scanning, and their circumpapillary RNFL thickness was measured using SD OCT, followed by regular serial measurements of RNFL thickness at intervals of ≥6 months. The LCD from the levels of Bruch's membrane (BM, LCD-BM) and the anterior sclera (AS, LCD-AS), and LC curvature index (LCCI) were measured by SD OCT at 3 locations: superior midperipheral, midhorizontal, and inferior midperipheral. The rate of RNFL thinning over time was determined by linear regression of serial OCT measurements of RNFL thickness. Factors associated with the rate of OCT RNFL thinning. Univariate analysis showed that larger LCD-BM (P = 0.001), LCD-AS (P < 0.001), and LCCI (P < 0.001) were all significantly associated with a faster rate of global RNFL thinning. The LCCI showed a stronger correlation with the rate of global RNFL thinning than LCD-BM (P < 0.001) or LCD-AS (P < 0.001). Of the 3 variables, only LCCI remained significant on multivariate analysis (P < 0.001). Disc hemorrhage during follow-up (P = 0.003), wider parapapillary atrophy β-zone (P = 0.017), and greater global RNFL thickness (P = 0.040) were also significantly associated with a faster rate of global RNFL thinning. Morphology of LC was significantly associated with the rate of progressive RNFL thinning. Curvature of LC better predicted progressive RNFL thinning than did LCD measured from the BM or AS.

Lee EJ ，Kim TW ，Kim H ，Lee SH ，Girard MJA ，Mari JM ... -  《-》

Evaluating displacement of lamina cribrosa following glaucoma surgery.

Krzyżanowska-Berkowska P ，Melińska A ，Helemejko I ，Robert Iskander D ... -  《-》

Long-Term Shape, Curvature, and Depth Changes of the Lamina Cribrosa after Trabeculectomy.

To evaluate changes in lamina cribrosa (LC) shape, curvature, and depth after trabeculectomy. Prospective, observational case series. A total of 112 patients (118 eyes) with open- or closed-angle glaucoma undergoing trabeculectomy. The optic nerve head was imaged using enhanced depth imaging spectral-domain OCT before trabeculectomy and at 6 follow-up visits throughout the first postoperative year. The anterior LC surface and Bruch's membrane opening were marked in the serial horizontal B scans for the analysis of LC parameters using Morphology 1.0 software. Postoperative morphologic LC changes were assessed. The postoperative LC global shape index (GSI), nasal-temporal (N-T) and superior-inferior (S-I) curvatures, and mean and sectoral LC depth (LCD). The mean LC GSI increased only during the early postoperative period (P = 0.02), resulting in a change toward the saddle-rut shape. There was a flattening of the LC curvature in N-T (P < 0.001) and S-I (P = 0.003) meridians 12 months after trabeculectomy. A shallowing of the mean and sectoral LCD from baseline was significant throughout the entire follow-up period (P < 0.001) and progressed up to postoperative month 6. Twenty-eight patients showed a deepening of the LC from baseline in at least 1 visit. Eyes with shallower LCD compared with baseline responded to intraocular pressure (IOP) reduction with greater movement anteriorly than eyes with deeper LCD (P = 0.002). Greater IOP reduction (P = 0.007), less retinal nerve fiber layer thinning over the year (P = 0.003), and more superiorly-inferiorly curved baseline LC (P = 0.001) were associated with an increase in GSI. Younger age and IOP reduction were related to LC shallowing (P < 0.001, P = 0.002) and N-T flattening (P < 0.001). In most eyes, trabeculectomy resulted in long-term flattening and shallowing of the LC. However, in some eyes, LC deepened from baseline. Change in LC global shape appeared to be temporal. Reduction in IOP plays an important role in the early phase of LC change; however, in the later phase, LC remodeling may play a crucial role in view of stable IOP.

Kadziauskienė A ，Jašinskienė E ，Ašoklis R ，Lesinskas E ，Rekašius T ，Chua J ，Cheng CY ，Mari JM ，Girard MJA ，Schmetterer L ... -  《-》