Pdf increased elastin expression in astrocytes of the. While the exact pathogenesis remains unclear, damage due to glaucoma is believed to first occur at the lamina cribrosa lc, a collagenous meshwork in the optic nerve head through which all retinal. The lamina cribrosa is a sievelike perforation in the posterior part of the sclera, that. While for many years the research on the lc was essentially dependent on histology and modelling, a number of recent advances in. The pressureinduced deformation response of the human. The associations between the thickness of the peripapillary sclera and the thickness of the lamina cribrosa may strengthen the notion of the peripapillary scleral.
This region is called the lamina cribrosa figure 1. The lamina cribrosa is thought to help maintain the pressure gradient between the inside of the eye and the surrounding tissue. Conclusion focal lamina cribrosa holetype defects were significantly associated with an increase in dh occurrence over the preceding 5 years. The lamina cribrosa lc is a fenestrated, threedimensional network of loadbearing. Lamina cribrosa definition of lamina cribrosa by medical. Naumann the lamina cribrosa is a sievelike perforation in the posterior part of the sclera, that allows passage of the retinal ganglion cell axons and central retinal vessels and preserves a pressure gradient between. The lamina cribrosa is composed of lamina cribrosa pores lcps which differ in their size, shape and visibility between various regions of the optic nerve head and between glaucomatous eyes and normal eyes. Pdf in vivo assessment of lamina cribrosa microstructure. The clinical importance of eyespecific lma discordance warrants further study.
Lamina cribrosa reversal after trabeculectomy and the rate. Cribriform plate the horizontal bone plate perforated with several holes for the passage of olfactory nerve filaments from the nasal cavity. Age related compliance of the lamina cribrosa in human eyes. Pdf mathematical modeling of the biomechanics of the. However, the clinical relevance of the presence of lc findings at the. In human anatomy, the cribriform plate horizontal lamina or lamina cribrosa of the ethmoid bone is received into the ethmoidal notch of the frontal bone and roofs in the nasal cavities. The posterior sclera of human eyes from 7 donors was subjected to controlled pressurization between 545 mmhg. The posterior scleral cup of 8 eyes from 6 human donors was mounted onto a custom inflation chamber. Mathematical modeling of the biomechanics of the lamina cribrosa under elevated intraocular pressures.
Glaucoma biomechanical responses of lamina cribrosa to intraocular pressure change assessed by optical coherence tomography in glaucoma eyes harry quigley,1 karun arora,1 sana idrees,1 francisco solano, 1 sahar bedrood,1 christopher lee,1 joan jefferys, 1 and thao d. Evaluation of the lamina cribrosa in patients with. The lamina cribrosa, a multilayered sievelike structure in the optic nerve head, has been proposed as a primary site of axonal damage in glaucoma. The lamina cribrosa likely plays an important role in retinal ganglion cell axon injury in glaucoma. Recent advances in oct imaging of the lamina cribrosa. The lamina is an active living structure that responds to strain by changing morphology at the microscale and macroscale in glaucoma. Pdf optic disc hemorrhage and lamina cribrosa defects in. Lamina cribrosa thickness correlated with posterior. Pdf age related compliance of the lamina cribrosa in. A look at the role of oct and the relationship between the depth of the lamina cribrosa, the stage of glaucoma, and the extent of vision loss. Anterior lamina cribrosa surface depth, age, and visual field.
The ability to visualise this structure has the potential to help increase our understanding of the disease and be useful in the early detection of glaucoma. It is theorized that elevated iop causes posterior bowing of the lc cupping resulting in dis. Both disc hemorrhages dh and focal lamina cribrosa lc defects are recently considered as a progression factor in glaucoma. A a healthy optic nerve head, with the lamina cribrosa beams and pores. Although histological studies have provided evidence of structural changes to the lamina cribrosa, even in early stages of glaucoma, until recently, the ability to evaluate the lamina cribrosa. This study investigated the inflation response of the lamina cribrosa lc and adjacent peripapillary sclera pps in postmortem human eyes with no history of glaucoma. Given that posterior bowing of the lamina cribrosa lc is a principle event in the development of glaucomatous damage, assessment of the lc morphology may have clinical utility in diagnosing and. Girard 3,5, and manojit pramanik 1 1school of chemical and biomedical engin eering, nanyang technological university, 62 nanyang drive, singapore 637459. Now theres evidence that the lamina cribrosa lc may also be the site of an.
In vivo evaluation of focal lamina cribrosa defects in. The lamina cribrosa has been reported to move anteriorly toward the vitreous and posteriorly away from the vitreous in response to lowering iop in glaucomatous eyes. Lamina cribrosa may warn of vf loss american academy of. Glaucoma is an optic neuropathy that is the second leading cause of blindness worldwide. B glaucoma damage results in thinning, excavation and posterior insertion of the lamina cribrosa. Microcapillary imaging of lamina cr ibrosa in porcine eyes. To determine whether abnormal elastin synthesis in the glaucomatous optic nerve head and lamina cribrosa is due to elevated intraocular pressure iop or secondary to axonal injury, monkeys with elevated iop and with optic nerve transection were. Localized alterations of the lamina cribrosa insertion in glaucoma with varying degrees of downward sloping of the anterior laminar surface toward its insertion identified in enhanced depth imaging optical coherence tomographic oct scans b, e, and h. Purpose to assess the effect of age on spectraldomain optical coherence tomography sdoctdetected lamina cribrosa depth while controlling for visual. Nguyen2 1glaucoma center of excellence, wilmer ophthalmological institute, johns hopkins university school of medicine, baltimore. Retinal vein occlusion cribriform plate this is a part.
Note the detailed microstructure of the lamina cribrosa. Posterior displacement of the lamina cribrosa in normal. The lamina cribrosa is regarded as the primary site of pathogenesis in glaucoma. Morphometry of the human lamina cribrosa surface josr d. Lamina cribrosa pore shape and size as predictors of. Biomechanical responses of lamina cribrosa to intraocular. Relationship of corneal hysteresis and anterior lamina. Microcapillary imaging of lamina cr ibrosa in porcine eyes using photoacoustic microscopy mohesh moothanchery 1,2, thanadet chuangsuwanich 3, alvan tsz chung yan 3, leopold schmetterer 4,5,6,7,8, michael j. Using oct to measure anterior lamina cribrosa depth. A histologic study has shown deformation of the posterior lamina cribrosa in monkey eyes with induced evaluation of the lamina cribrosa in patients with diabetes mellitus using. Connective tissue and glial cell structural elements were greater in.
Intracranial and intraocular pressure at the lamina. The lamina cribrosa is the putative site of retinal ganglion cell axonal injury in glaucoma. Lamina cribrosa microarchitecture in normal monkey eyes part 1. Developmental anatomy of the retinal and choroidal vasculature 11. Characterization of the connective tissue changes of the optic nerve head and lamina cribrosa with glaucoma.
Pdf deformation of the lamina cribrosa and optic nerve. Lamina cribrosa pore movement during acute intraocular. Developmental anatomy of the retinal and choroidal vasculature b anandapte and j g hollyfield, cleveland clinic, cleveland, oh, usa. Developmental anatomy of the retinal and choroidal. The structure of the lamina cribrosa of the human eye. Association between focal lamina cribrosa defects and. Lamina cribrosa thickness was not significantly related to temporary central retinal artery occlusion p 0. The cribriform plate is narrow with deep grooves supporting the olfactory bulb, and is perforated by olfactory foramina allowing the passage of the olfactory. The disease is characterized by damage to the retinal ganglion cells, resulting in irreversible vision loss. Lamina cribosa definition of lamina cribosa by medical.
The lack of association between defect size and dh suggests that dh and lamina defects may have separate links to the glaucomatous process. We sought to 1 better understand optic nerve head onh structure and anterior lamina cribrosa surface alcs microarchitecture between fellow eyes of living, normal nonhuman primates and 2 characterize the timecourse of in vivo structural changes in the onh, alcs microarchitecture, and. Being structurally weaker than the much thicker and denser sclera, the lamina cribrosa is more sensitive to changes in the intraocular pressure and tends to react to increased pressure through posterior displacement. Recent advances in oct imaging of the lamina cribrosa ian a sigal,1,2 bo wang,1,2 nicholas g strouthidis,3,4 tadamichi akagi,5 michael j a girard4,6 1department of ophthalmology, upmc eye center, eye and ear institute, ophthalmology and visual. The objective of this study was to measure the pressureinduced deformation response of the human lamina cribrosa lc and analyze for variations with age and anatomical region. The blood vessels of the sclera are largely confined to a superficial layer of tissue, and these, along with the conjunctival vessels, are responsible for the bright redness of the inflamed eye. Relative contributions of intracranial pressure and intraocular. To determine whether the reversal of lamina cribrosa lc displacement observed after trabecu. Mardin, ursula schlorzerschrehardr, and gottfried o. The lamina cribrosa is a complex threedimensional structure that is tasked with the conflicting functions of providing structural support to the onh by withstanding ioprelated mechanical strain, while also providing an open pathway for the retinal ganglion cell axons to leave the eye. The inflation response of the human lamina cribrosa and.
Light microscopy of specimens of human eyes cut in cross section at the level of the lamina cribrosa showed variation in structural anatomy, as demonstrated previously in certain primate eyes. To characterize the relative contributions of intraocular pressure iop and intracranial pressure icp on lamina cribrosa lc. Although the lamina cribrosa is widely believed to be the primary site of injury in glaucoma, the arcuate field defects do not validate the lc as the primary site of injury. Lamina cribrosa reversal after trabeculectomy and the rate of progressive retinal nerve fiber layer thinning eun ji lee, md, taewoo kim, md purpose. The lamina cribrosa lc is believed to be the site of injury to retinal ganglion cell axons in glaucoma. Although histological studies have provided evidence of structural changes to the lamina cribrosa, even. The structure of the lamina cribrosa was studied by histological and immunocytochemical techniques and by scanning and transmission. Although histological studies have provided evidence of structural changes to the lamina cribrosa, even in early stages of glaucoma, until recently, the ability to evaluate the lamina cribrosa in vivo has been limited.
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