Trans-lamina Cribrosa Pressure Difference Activates Mechanical Stress Signal Transduction to Induce Glaucomatous Optic Neuropathy: A Hypothesis

Glaucoma is a group of diseases involving a progressive optic neuropathy of unknown etiology. It is one of the leading causes of blindness worldwide. It has been postulated that glaucomatous optic neuropathy may result from mechanical stresses on the optic nerve fibers passing through the lamina cribrosa (LC), from ischemia in the LC region, or from a combination of these two.

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Faculty Opinions recommendation of Differentiation of compressive from glaucomatous optic neuropathy with spectral-domain optical coherence tomography.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718348640.793499331 ◽

2014 ◽

Author(s):

K Sheng Lim

Keyword(s):

Optical Coherence Tomography ◽

Optic Neuropathy ◽

Spectral Domain ◽

Glaucomatous Optic Neuropathy ◽

Optical Coherence

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Parapapillary atrophy in optic neuropathies: Histology and clinical relevance

European Journal of Ophthalmology ◽

10.1177/11206721211060655 ◽

2021 ◽

pp. 112067212110606

Author(s):

Ana Banc ◽

Stefania Bianchi Marzoli

Keyword(s):

Optic Nerve ◽

Optic Neuropathy ◽

Optic Nerve Head ◽

Clinical Findings ◽

Age Related Macular Degeneration ◽

Glaucomatous Optic Neuropathy ◽

Age Related ◽

High Resolution Images ◽

Parapapillary Atrophy ◽

Optic Nerve Disorders

Parapapillary atrophy is one of the parameters of the optic nerve head area which are assessed during the ophthalmoscopic examination particularly useful to characterize glaucomatous optic neuropathy. Optical coherence tomography evaluation provides high-resolution images of the optic nerve head and surrounding area, and can be used to study parapapillary atrophy. Different parapapillary atrophy zones were described depending on their histological features and research has been conducted to investigate the possible association between the presence and/ or size of parapapillary atrophy zones and several optic nerve disorders. In this review we discuss the histology and the clinical findings related to parapapillary atrophy in patients with glaucomatous optic neuropathy, non-glaucomatous optic neuropathies (e.g. arteritic and non-arteritic anterior ischemic optic neuropathies; suprasellar and parasellar tumors), and other ocular conditions (e.g. high myopia; age-related macular degeneration). Two different histologic classifications were identified. Parapapillary atrophy was demonstrated in glaucoma and glaucoma-like neuropathies, but not in other types of optic nerve disorders.

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An Experimental Basis for Implicating Excitotoxicity in Glaucomatous Optic Neuropathy

Survey of Ophthalmology ◽

10.1016/s0039-6257(99)00017-x ◽

1999 ◽

Vol 43 ◽

pp. S142-S150 ◽

Cited By ~ 65

Author(s):

Christian K Vorwerk ◽

Madhu S.R Gorla ◽

Evan B Dreyer

Keyword(s):

Optic Neuropathy ◽

Glaucomatous Optic Neuropathy ◽

Experimental Basis

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Electrophysiological markers of preclinical diagnosis of glaucomatous optic neuropathy

Russian Ophthalmological Journal ◽

10.21516/2072-0076-2021-14-1-35-41 ◽

2021 ◽

Vol 14 (1) ◽

pp. 35-41

Author(s):

M. O. Kirillova ◽

M. V. Zueva ◽

I. V. Tsapenko ◽

A. N. Zhuravleva

Keyword(s):

Optic Neuropathy ◽

Ganglion Cells ◽

Open Angle Glaucoma ◽

Statistical Significance ◽

Photopic Negative Response ◽

Glaucomatous Optic Neuropathy ◽

Functional Changes ◽

Bright Flash ◽

Pattern Size ◽

Group 2

Purpose: to evaluate the changes in electrophysiological indicators reflecting various aspects of the function of retinal ganglion cells (RGC) and their axons in the early diagnosis of glaucomatous optic neuropathy (GON).Material and methods. Two clinical groups, (1) 35 patients (60 eyes) aged 49 to 70 with suspected glaucoma and (2) 16 patients (30 eyes) aged 43–68 with initial primary open-angle glaucoma (POAG), and a comparison group of 38 relatively healthy subjects (45 eyes) aged 42–70 were tested for pattern-reversed visual evoked potentials (PVEP), transient and stationary pattern-ERGs (PERG) according to ISCEV, and photopic negative response (PhNR).Results. The P100 amplitudes in both clinical groups differed significantly from the norm in PVEP on small and large patterns. The elongation of peak latency (T) of P100 compared with norm was significant for the stimulus 1° in group 2. In both groups of patients, increased variability of the temporal parameters of PERG and PVEP for small patterns was found. In groups 1 and 2, a decrease in the amplitude of P50 and N95 peaks of transient PERG for all stimuli was revealed, which was the most significant for the 0.3° pattern. In group 1, the N95 peak was significantly delayed in PERG for large patterns. A statistically significant reduction in the steady-state PERG's amplitude was found in the groups of suspected glaucoma and initial POAG. The sharpest changes were found for small (0.8° and 0.3°) patterns. The elongation of T compared to the norm was most pronounced for PERG at 0.3°, but due to the high variability of temporary indicators within the group, it had no statistical significance. The amplitude of PhNR was significantly different from the norm in the ERG for a flash of 3.0 cd·sec/m2.Conclusion. In patients with suspected glaucoma, a decrease in the P100 VEP amplitude with the simultaneous elongation of T may be considered as a criteria for the plastic stage at the level of lateral geniculate nucleus. Markers of functional changes in RGCs are the decrease in the amplitude of PhNR in response to bright flash, and P50 and N95 of PERG for pattern size 0.3°. The results indicate a greater vulnerability of the parvocellular system to early events in the development of GON.

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