1
|
Wang B, Tran H, Smith MA, Kostanyan T, Schmitt SE, Bilonick RA, Jan NJ, Kagemann L, Tyler-Kabara EC, Ishikawa H, Schuman JS, Sigal IA, Wollstein G. In-vivo effects of intraocular and intracranial pressures on the lamina cribrosa microstructure. PLoS One 2017; 12:e0188302. [PMID: 29161320 PMCID: PMC5697865 DOI: 10.1371/journal.pone.0188302] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 11/04/2017] [Indexed: 11/19/2022] Open
Abstract
There is increasing clinical evidence that the eye is not only affected by intraocular pressure (IOP), but also by intracranial pressure (ICP). Both pressures meet at the optic nerve head of the eye, specifically the lamina cribrosa (LC). The LC is a collagenous meshwork through which all retinal ganglion cell axons pass on their way to the brain. Distortion of the LC causes a biological cascade leading to neuropathy and impaired vision in situations such as glaucoma and idiopathic intracranial hypertension. While the effect of IOP on the LC has been studied extensively, the coupled effects of IOP and ICP on the LC remain poorly understood. We investigated in-vivo the effects of IOP and ICP, controlled via cannulation of the eye and lateral ventricle in the brain, on the LC microstructure of anesthetized rhesus monkeys eyes using the Bioptigen spectral-domain optical coherence tomography (OCT) device (Research Triangle, NC). The animals were imaged with their head upright and the rest of their body lying prone on a surgical table. The LC was imaged at a variety of IOP/ICP combinations, and microstructural parameters, such as the thickness of the LC collagenous beams and diameter of the pores were analyzed. LC microstructure was confirmed by histology. We determined that LC microstructure deformed in response to both IOP and ICP changes, with significant interaction between the two. These findings emphasize the importance of considering both IOP and ICP when assessing optic nerve health.
Collapse
Affiliation(s)
- Bo Wang
- Department of Ophthalmology, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, Pittsburgh, Pennsylvania, United States of America
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Huong Tran
- Department of Ophthalmology, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, Pittsburgh, Pennsylvania, United States of America
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Matthew A. Smith
- Department of Ophthalmology, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, Pittsburgh, Pennsylvania, United States of America
| | - Tigran Kostanyan
- Department of Ophthalmology, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, Pittsburgh, Pennsylvania, United States of America
| | - Samantha E. Schmitt
- Department of Ophthalmology, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, Pittsburgh, Pennsylvania, United States of America
| | - Richard A. Bilonick
- Department of Ophthalmology, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, Pittsburgh, Pennsylvania, United States of America
| | - Ning-Jiun Jan
- Department of Ophthalmology, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, Pittsburgh, Pennsylvania, United States of America
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Larry Kagemann
- New York University Langone Eye Center, New York University School of Medicine, New York, New York, United States of America
| | - Elizabeth C. Tyler-Kabara
- Department of Neurosurgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Hiroshi Ishikawa
- New York University Langone Eye Center, New York University School of Medicine, New York, New York, United States of America
| | - Joel S. Schuman
- New York University Langone Eye Center, New York University School of Medicine, New York, New York, United States of America
| | - Ian A. Sigal
- Department of Ophthalmology, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, Pittsburgh, Pennsylvania, United States of America
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Gadi Wollstein
- New York University Langone Eye Center, New York University School of Medicine, New York, New York, United States of America
| |
Collapse
|
2
|
Aptel F, Weinreb RN, Chiquet C, Mansouri K. 24-h monitoring devices and nyctohemeral rhythms of intraocular pressure. Prog Retin Eye Res 2016; 55:108-148. [PMID: 27477112 DOI: 10.1016/j.preteyeres.2016.07.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 07/07/2016] [Accepted: 07/12/2016] [Indexed: 01/26/2023]
Abstract
Intraocular pressure (IOP) is not a fixed value and varies over both the short term and periods lasting several months or years. In particular, IOP is known to vary throughout the 24-h period of a day, defined as a nyctohemeral rhythm in humans. In clinical practice, it is crucial to evaluate the changes in IOP over 24 h in several situations, including the diagnosis of ocular hypertension and glaucoma (IOP is often higher at night) and to optimize the therapeutic management of glaucoma. Until recently, all evaluations of 24-h IOP rhythm were performed using repeated IOP measurements, requiring individuals to be awakened for nocturnal measurements. This method may be imperfect, because it is not physiologic and disturbs the sleep architecture, and also because it provides a limited number of time point measurements not sufficient to finely asses IOP changes. These limitations may have biased previous descriptions of physiological IOP rhythm. Recently, extraocular and intraocular devices integrating a pressure sensor for continuous IOP monitoring have been developed and are available for use in humans. The objective of this article is to present the contributions of these new 24-h monitoring devices for the study of the nyctohemeral rhythms. In healthy subjects and untreated glaucoma subjects, a nyctohemeral rhythm is consistently found and frequently characterized by a mean diurnal IOP lower than the mean nocturnal IOP, with a diurnal bathyphase - usually in the middle or at the end of the afternoon - and a nocturnal acrophase, usually in the middle or at the end of the night.
Collapse
Affiliation(s)
- Florent Aptel
- Inserm U1042, Hypoxia and Physiopathology Laboratory, University Grenoble Alpes, Grenoble, France; Department of Ophthalmology, University Hospital, CHU Grenoble, Grenoble, France
| | - Robert N Weinreb
- Hamilton Glaucoma Center, Shiley Eye Center and Department of Ophthalmology, University of California, San Diego, La Jolla, CA, USA
| | - Christophe Chiquet
- Inserm U1042, Hypoxia and Physiopathology Laboratory, University Grenoble Alpes, Grenoble, France; Department of Ophthalmology, University Hospital, CHU Grenoble, Grenoble, France
| | - Kaweh Mansouri
- Glaucoma Center, Montchoisi Clinic, Swiss Vision Network, Lausanne, Switzerland; Department of Ophthalmology, University of Colorado School of Medicine, Denver, CO, USA.
| |
Collapse
|
3
|
Jonas JB, Wang N, Yang D. Translamina Cribrosa Pressure Difference as Potential Element in the Pathogenesis of Glaucomatous Optic Neuropathy. Asia Pac J Ophthalmol (Phila) 2016; 5:5-10. [PMID: 26713405 DOI: 10.1097/apo.0000000000000170] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The main proven risk factor for glaucomatous optic neuropathy (GON) is an intraocular pressure (IOP) higher than the pressure sensibility of the optic nerve head allows. Fulfilling Koch postulates, numerous studies have shown that the presence of high IOP leads to GON, that lowering IOP stops the progression of GON, and that a re-increase in IOP again causes the progression of GON. There are, however, many patients with glaucoma who have statistically normal or low IOP, and despite low IOP values, they develop progressing GON. These observations led to findings that IOP is only 1 of 2 determinants of the translamina cribrosa pressure difference (TLCPD), which is the main pressure-related parameter for the physiology and pathophysiology of the optic nerve head. The second parameter influencing TLCPD is orbital cerebrospinal fluid pressure (CSFP) as the counter pressure against IOP across the lamina cribrosa. Recent experimental and clinical studies have suggested that a low CSFP could be associated with GON in normal-pressure glaucoma. These investigations included studies with an experimental long-term reduction in CSFP in monkeys, population-based studies, and clinical retrospective and prospective investigations on patients with normal-pressure glaucoma. Besides TLCPD, other ocular parameters influenced by CSFP may be choroidal thickness, retinal vein pressure and diameter, occurrence of retinal vein occlusions, and occurrence and severity of diabetic retinopathy.
Collapse
Affiliation(s)
- Jost B Jonas
- From the *Department of Ophthalmology, Medical Faculty Mannheim, Ruprecht-Karls-University, Seegartenklinik Heidelberg, Germany; †Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory; and ‡Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing, China
| | | | | |
Collapse
|