LETTERS

depth in the cornea of 420 mm2,3; the preoperative pa-chymetry of the donor cornea was 856 mm. Accordingto the 1-week results, the postoperative pachymetrywas 794 mm.Did the authors perform additional pachy-metry to get an indication as to the thickness of thelamellar donor button following laser treatment? Howdo they explain the postoperative reading?

Using the 20/10 Femtec laser (20/10 Perfect VisionGmbH), we have found that it is possible to performposterior stromal lamellar dissection with an increasein accuracy that is inversely proportional to the severityof the corneal edema. Deturgescing the cornea beforeablation may have improved the accuracy of the abla-tion in the case reported. Following laser lamellardissection, the cornea was stored for 1 week in organculture medium. Other authors have reported signifi-cant swelling of the posterior cornea lamellae followinglamellae dissection in de-epithelialized cornea and thenstorage in Optisol GS.4 Do the authors feel the choice ofstorage medium accounted for their result?

We commend the authors on the use of this newtechnology, which will eventually allow standardizedaccurate lamellar buttons to be precut before implanta-tion, and look to the future of performing a completefemtosecond laser endothelial keratoplasty procedurein which both the host bed and donor button are pre-pared by laser.

Jodhbir S. Mehta, FRCOphthYong M. Por, FRCS(Ed)

Howard Cajucom-Uy, MDAnand Parthasarathy, MDDonald T. Tan, FRCOphth

Singapore

REFERENCES1. Cheng YYY, Pels E, Nuijts RMMA. Femtosecond-laser–assisted

Descemet’s stripping endothelial keratoplasty. J Cataract Refract

‘‘Optical’’ coherence tomography, not ‘‘ocular’’coherence tomography

I congratulate Fine, Hoffman, and Packer1 for thebeautiful illustrations and optical coherence tomogra-phy (OCT) images of cataract incisions in their recentarticle. However, as a co-inventor of OCT and theone who coined the term, I would like to point outthat ‘‘ocular coherence tomography’’ is not an accept-able substitute for ‘‘optical coherence tomography.’’The unfortunate similarity has caused the 2 terms tobe used interchangeably, sometimes even in peer-re-viewed journals.2–4 But optical coherence tomographyrefers to optical (lightwave) coherence gating to obtainthe depth information used for cross-sectional imaging(tomography).5 Although OCT is often used to imageocular tissue, it is also used in angioscopy and manyother medical and nonmedical applications. I urgeauthors and editors to make sure the term is usedcorrectly.

David Huang, MD, PhDLos Angeles, California, USA

REFERENCES1. Fine IH, Hoffman RS, Packer M. Profile of clear corneal cataract

incisions demonstrated by ocular coherence tomography. J Cat-

aract Refract Surg 2007; 33:94–97

2. Lim LL, Watzke RC, Lauer AK, Smith JR. Ocular coherence to-

mography in acute posterior multifocal placoid pigment epitheli-

opathy [letter]. Clin Exp Ophthalmol 2006; 34:810–812

3. Joondeph BC, Nguyen H. Ocular coherence tomography findings

with retained submacular perfluoron [letter]. Clin Exp Ophthalmol

2006; 34:85–86

4. Tseng JJ, Turano MR Jr, Langton K, Chang S. Measurement of

retinal thickness by ocular coherence tomography in a case of

scleral transparency in high myopia. Am J Ophthalmol 2004;

138:169–170

5. Huang D, Swanson EA, Lin C-P, et al. Optical coherence tomog-

raphy. Science 1991; 254:1178–1181

REPLY: We are grateful to Huang, not only for hisinnovations, but for correcting our improper use ofOCT. In all future publications, we will make certainthat the proper term, optical coherence tomography,is used.dI. Howard Fine, MD, Richard S. Hoffman,MD, Mark Packer, MD

Femtosecond laser for endothelial keratoplastyWecongratulateCheng et al.1 on the use of the femto-

second laser for lamellar dissection of the donor disk forendothelial keratoplasty (femto-PLK). However, wewere confused by the discrepancy in the pachymetryreading reported by the authors. The IntraLase femto-second laser (IntraLaseCorp.) has amaximumresection

Surg 2007; 33:152–155

2. Sarayba MA, Juhasz T, Chuck RS, et al. Femtosecond laser pos-

terior lamellar keratoplasty; a laboratory model. Cornea 2005;

24:328–333

3. Soong HK, Mian S, Abbasi O, Juhasz T. Femtosecond laser-

assisted posterior lamellar keratoplasty: initial studies of surgical

technique in eye bank eyes. Ophthalmology 2005; 112:44–49

4. Suwan-apichon O, Reyes JMG, Griffin NB, et al. Microkeratome

versus femtosecond laser predissection of corneal grafts for an-

terior and posterior lamellar keratoplasty. Cornea 2006; 25:

966–968

REPLY: We appreciate the comments of Mehta et al.The IntraLase femtosecond laser used in the study al-lows amaximumcutting depth of 400mmfor a lamellarplane. We used whole donor eyes for the preparationof the lamellar plane, and these eyes tend to be

Q 2007 ASCRS and ESCRS

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0886-3350/07/$dsee front matter 1141doi:10.1016/j.jcrs.2007.02.047