Dua Harminder S, Faraj Lana A, Kenawy Mohamed B, AlTaan Saief, Elalfy Mohamed S, Katamish Tarek, Said Dalia G
Larry A Donoso Laboratory for eye research, Academic Section of Ophthalmology, Division of Clinical Neuroscience, University of Nottingham, Nottingham, UK.
Nottingham University Hospitals NHS Trust, Nottingham, UK.
Acta Ophthalmol. 2018 Feb;96(1):69-76. doi: 10.1111/aos.13460. Epub 2017 May 8.
To examine the movement of air injected in the cornea in simulated deep anterior lamellar keratoplasty (DALK), from the needle tip to the formation of different types of big bubbles (BB) and to ascertain how air travels through the stroma and pre-Descemet's layer [Dua's layer (PDL)] to create a type-1 (air between PDL and deep stroma) and type-2BB (air between PDL and Descemet's membrane).
Air was injected in 57 sclerocorneal discs and the passage recorded. Leaking points and sites of commencement of type-1 and type-2BB were examined by scanning electron microscopy. Stromal distribution of air pockets was studied by light microscopy. Uninjected corneas served as controls.
Injected air followed a consistent pattern, initially as radial tracks to the limbus, then as circumferential bands along the limbus and finally centripetally to create predominantly a type-1BB. Type-2BB started at the periphery, by air emerging through clusters of tiny fenestrations discovered in the periphery of PDL. Fifteen to 20 such clusters were also seen in control samples on either side of the Descemet's attachment. Type-1BB was formed by air emerging through wide spaces between lamellae of deep stroma. Histologically, the circumferential band revealed an aggregation of air pockets in the mid-stroma.
The consistent pattern of passage of air is indicative of the architecture and microanatomy of the corneal stroma where collagen lamellae are orthogonally arranged centrally and as a circular annulus at the periphery. The novel peripheral fenestrations explain the peripheral commencement of a type-2BB and the escape of air into the anterior chamber during DALK.
研究在模拟深板层角膜移植术（DALK）中注入角膜的空气从针尖到形成不同类型大气泡（BB）的运动过程，并确定空气如何穿过基质和后弹力层前层[杜阿层（PDL）]以形成1型（PDL与深层基质之间有空气）和2型BB（PDL与后弹力膜之间有空气）。
向57个巩膜角膜片中注入空气并记录其通过情况。通过扫描电子显微镜检查1型和2型BB的渗漏点和起始部位。通过光学显微镜研究气腔的基质分布。未注入空气的角膜作为对照。
注入的空气遵循一致的模式，最初呈放射状轨迹至角膜缘，然后沿角膜缘呈环形带，最后向心形成主要为1型BB。2型BB从周边开始，空气通过在PDL周边发现的微小窗孔簇逸出。在对照样本的后弹力膜附着两侧也可见15至20个这样的簇。1型BB是由空气通过深层基质板层之间的宽阔间隙逸出形成的。组织学上，环形带显示基质中部有气腔聚集。
空气一致的通过模式表明角膜基质的结构和微观解剖结构，其中胶原板层在中央呈正交排列，在周边呈环形排列。新发现的周边窗孔解释了2型BB的周边起始以及DALK期间空气进入前房的现象。
