New Concept of DSAEK Injecting System

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New Concept of DSAEK Injecting System
Takeshi Ide, MD,PhD, Terrence P. OBrien, MD,
Sonia H. Yoo, MD
Bascom Palmer Eye Institiute, Miami, FL, USA
Financial
Disclosure Educational Research Grant was
provided by KANEKA(Osaka Japan) Takeshi Ide, MD
 research for KANEKA Terrence OBrien MD
consultant for AMO, Alcon, Allergan, BL, Inspire
Pharmaceuticals, Ista Pharmaceuticals Sirion
Therapeutics, and Vistakon Pharmaceuticals Sonia
Yoo, MD consultant for Alcon research for Carl
Zeiss Meditec travel expenses by IntraLase
Corpation None of the authors have a propriety
interest in this study.
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Abstract
To report the efficacy and safety of a new DSAEK
tissue injecting system in an in vitro
experimental model. Three human DSAEK donor
tissues were prepared and loaded into our DSAEK
injecting system. The tissues were subsequently
injected into balanced salt solution (BSS) and
stained with alizarin red S and trypan blue.
Imaging software was then utilized to identify
and analyze the endothelial cell damage area.
This DSAEK injecting system functioned
adequately for all three donor tissues. The cell
damage area was 12.983.13, which was comparable
or less than reported damage areas by other
injecting devices. This injecting system was as
safe as other reported devices with regard to
cell damage. This device also can maintain the
anterior chamber, inject air, and release
pressure. These features could significantly
enhance the safety of DSAEK.
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Purpose
To report the efficacy and safety of a new DSAEK
tissue injection system in an in vitro
experimental model.
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Materials
New DSAEK Injection System
(A) Injector Body with two pushers to insert
donor tissues into host eyes( one pusher is for
tissue injection and the other for releasing AC
pressure) (B) 1ml-Syringe for injecting air into
anterior chamber (AC). (C) Roller Clamp to
control the flow rate of ophthalmic surgical
solution (D) Balanced Salt Solution (BSS) to
maintain AC.
D
C
A
B
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Materials
Safety mechanisms
(A) Insert the nozzle part of the injector,
irrigate BSS solution to maintain AC (B) Inject
the tissues into the AC (C) Inject air bubble to
lift up the tissues
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Materials
Safety mechanisms
(D) Reduce IOP to avoid sudden AC collapse and
the sudden ejection of the tissues from the AC as
a result of the high IOP. (E) Remove the
Injector, and finish tissue insertion.
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Experimental Methods

• Three human DSAEK donor tissues were prepared
  with a mechanical microkeratome
• 2. The tissues were loaded onto the injector
• 3. The tissues were injected into BSS
• 4. The tissues were stained with alizarin red S
  and trypan blue.
• 5. The area of cell damage was analyzed with
  Photoshop

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Methods

• Injector body
• (B) Hinge part
• (C) Place the DSAEK tissue
• (D) Cohesive ophthalmic
• viscoelastic device (OVD) was
• placed on the endothelial side of
• the DSAEK donor tissues. Slide
• the injector pusher, set the inner
• cylinder over the tissue
• (E) Close the hinge part
• (F) Slide and tighten the hinge cover
• (G) Slide the injector-pusher,
• release the tissue into the BSS

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Results
Sample1 and three different gating conditions
Sample2 and three different gating conditions
Sample3 and three different gating conditions
Quantitative analysis of the acute endothelial
cell damage was performed by the method described
by Terry et al. 18, 23
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Results
Table Cell Damage Area Different Gating
Conditions by 3 different corneal specialists
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Conclusion

• Our new DSAEK injector functioned adequately and
  caused a relatively small cellular damage in the
  in vitro model.
• Our prototype has 3 safety mechanisms
• A. BSS Irrigation system to keep AC
• B. Air injection system to lift the tissue up
• C. IOP releasing system to avoid tissue ejection
• These are useful especially for surgeons who
  perform DSAEK occasionally, since non-volume
  DSAEK surgeons have difficulty in grasping and
  inserting the tissue using forceps on their first
  attempt.
• 3. These features can significantly enhance the
  safety of DSAEK procedures, though further device
  modifications and ex vivo and in vivo studies are
  needed prior to clinical use