[Skip to Navigation]
Views 226
Citations 0
Comment & Response
August 29, 2019

Lamina Cribrosa Pore Diameter and Spaceflight-Associated Neuro-ocular Syndrome—Reply

Author Affiliations
  • 1Memorial Sloan Kettering Cancer Center, New York, New York
  • 2Integrated Cardiovascular Exercise Physiology and Rehabilitation Laboratory, College of Nursing and Health Innovation, University of Texas at Arlington, Arlington
JAMA Ophthalmol. 2019;137(11):1331. doi:10.1001/jamaophthalmol.2019.3322

In Reply We thank Shinojima and colleagues for their interest in our study1 on exercise and swimming goggles in a model of spaceflight associated neuro-ocular syndrome (SANS). Spaceflight provokes increases in both intracranial pressure (ICP) and intraocular pressure (IOP).2 However, there is a greater increase in ICP relative to IOP, which results in an IOP-ICP mismatch and an anteriorly directed translaminar pressure gradient across the lamina cribrosa (LC).2 A negative translaminar pressure gradient is associated with adverse ocular changes2; accordingly, countermeasures that normalize this are of major importance in protecting the health of astronauts. To date, most SANS countermeasures have focused on reversing the spaceflight-associated fluid shifts to lower ICP, with tools such as a lower-body negative-pressure device.2 Our findings1 indicated that slightly increasing IOP with an inexpensive and convenient countermeasure, such as swimming goggles, could also normalize the translaminar pressure gradient. In addition, goggles may be a relatively safe intervention; the increase in IOP with goggles is small (approximately 3 mm Hg),1 and goggles are worn by competitive swimmers for hours daily without an increased prevalence of glaucoma.3

Limit 200 characters
Limit 25 characters
Conflicts of Interest Disclosure

Identify all potential conflicts of interest that might be relevant to your comment.

Conflicts of interest comprise financial interests, activities, and relationships within the past 3 years including but not limited to employment, affiliation, grants or funding, consultancies, honoraria or payment, speaker's bureaus, stock ownership or options, expert testimony, royalties, donation of medical equipment, or patents planned, pending, or issued.

Err on the side of full disclosure.

If you have no conflicts of interest, check "No potential conflicts of interest" in the box below. The information will be posted with your response.

Not all submitted comments are published. Please see our commenting policy for details.

Limit 140 characters
Limit 3600 characters or approximately 600 words