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. 2018 Jan;32(1):146-151.
doi: 10.1038/eye.2017.121. Epub 2017 Jun 30.

Air pressure changes in the creation and bursting of the type-1 big bubble in deep anterior lamellar keratoplasty: an ex vivo study

S L AlTaan  1 , I Mohammed  1 , D G Said  1 , H S Dua  1
Affiliations

Air pressure changes in the creation and bursting of the type-1 big bubble in deep anterior lamellar keratoplasty: an ex vivo study

S L AlTaan et al. Eye (Lond). 2018 Jan.

Abstract

PurposeTo measure the pressure and volume of air required to create a big bubble (BB) in simulated deep anterior lamellar keratoplasty (DALK) in donor eyes and ascertain the bursting pressure of the BB.Patients and methodsTwenty-two human sclera-corneal discs were used. Air was injected into the corneal stroma to create a BB and the pressure measured by means of a pressure converter attached to the system via a side port. A special clamp was designed to prevent air leak from the periphery of the discs. The pressure at which air emerged in the corneal tissue; the bursting pressure measured after advancing the needle into the bubble cavity and injecting more air; the volume of air required to create a BB and the volume of the BB were ascertained.ResultsType-1 BB were achieved in 19 and type-2 BB in 3 eyes. The maximum pressure reached to create a BB was 96.25+/- 21.61 kpa; the mean type-1 intrabubble pressure was 10.16 +/- 3.65 kpa. The mean bursting pressure of a type-1 BB was 66.65 +/- 18.65 kpa, while that of a type-2 BB was 14.77 +/- 2.44 kpa. The volume of air required to create a type-1 BB was 0.54 ml and the volume of a type-1 BB was consistently 0.1 ml.ConclusionsDua's layer baring DALK can withstand high intraoperative pressures compared to Descemet's membrane baring DALK. The study suggests that it could be safe to undertake procedures such as DALK-triple with a type-1 BB but not with a type-2 BB.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
(a) Pressure converter system K-144, (b) Real pressure record over time (red graph), the temperature of the pressure sensor (blue graph), the maximum pressure (pink graph), the minus pressure (green line). A full colour version of this figure is available at the Eye journal online.
Figure 2
Figure 2
(a) Pressure change over time (red line) in T1BB. (b) Pressure change over time (red line) in T2BB.
Figure 3
Figure 3
Compares the pressure calculated from the volume compression of the syringe and that measured directly with gauge (P=0.25).
See this image and copyright information in PMC

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