Dataset Information

The influence of subretinal injection pressure on the microstructure of the monkey retina.

ABSTRACT:

Purpose

To investigate the influence of subretinal injection pressure on the microstructure of the retina in a monkey model.

Methods

After vitrectomy, balanced salt solution was injected subretinally into one eye each of four cynomolgus monkeys while controlling the injection pressure. Initially, a pressure of 2 psi was used, and this was gradually increased to determine the minimum required pressure. Subsequent injections were performed at two pressures: minimum (n = 13) and high (n = 6). To compare the influence of these injection pressures on retinal structure, optical coherence tomography (OCT) was performed before surgery and every week afterwards. The monkeys were euthanized and their eyes were enucleated at 1 or 6 weeks after the injections. The eyes were processed for light microscopy and transmission electron microscopy (TEM) as well as for TdT-mediated dUTP nick end labeling.

Results

The minimum pressure required to perform subretinal injection was 6 psi. After injection at this pressure, both OCT and microscopy showed that the retinal structure was well-preserved throughout the experimental period at all injection sites. Conversely, after injection at high pressure (20 psi) OCT images at all injection sites showed disruption of the ellipsoid zone (EZ) after 1 week. Microscopy indicated damage to the photoreceptor outer segment (OS) and stratification of the retinal pigment epithelium (RPE). After 6 weeks, OCT demonstrated that the EZ had become continuous and TEM confirmed that the OS and RPE had recovered. Photoreceptor apoptosis was absent after subretinal injection at both pressures.

Conclusions

The retinal damage caused by subretinal injection increases depending on pressure, indicating that clinicians should perform subretinal injection at pressures as low as possible to ensure safety.

SUBMITTER: Takahashi K

PROVIDER: S-EPMC6312337 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Publications

The influence of subretinal injection pressure on the microstructure of the monkey retina.

Takahashi Kosuke K Morizane Yuki Y Hisatomi Toshio T Tachibana Takashi T Kimura Shuhei S Hosokawa Mio Morizane MM Shiode Yusuke Y Hirano Masayuki M Doi Shinichiro S Toshima Shinji S Araki Ryoichi R Matsumae Hiroshi H Kanzaki Yuki Y Hosogi Mika M Yoshida Atsushi A Sonoda Koh-Hei KH Shiraga Fumio F

PloS one 20181231 12

<h4>Purpose</h4>To investigate the influence of subretinal injection pressure on the microstructure of the retina in a monkey model.<h4>Methods</h4>After vitrectomy, balanced salt solution was injected subretinally into one eye each of four cynomolgus monkeys while controlling the injection pressure. Initially, a pressure of 2 psi was used, and this was gradually increased to determine the minimum required pressure. Subsequent injections were performed at two pressures: minimum (n = 13) and high ...[more]

PMID: 30596769

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Dataset Information

The influence of subretinal injection pressure on the microstructure of the monkey retina.

Purpose

Methods

Results

Conclusions

Publications

The influence of subretinal injection pressure on the microstructure of the monkey retina.

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