LASIK Eye Surgery

Researchers from Department of Ophthalmology, Mayo Clinic College of Medicine, in Rochester, Minnesota, have reported that they have:

• “… developed a program to determine cell densities in images from the ConfoScan 4 (Nidek, Inc., Freemont, CA) confocal microscope and compared densities to those determined from images from the Tandem Scanning Confocal Microscope (Tandem Scanning Corporation, Reston, VA).”¹

The researchers from Mayo Clinic College of Medicine, Rochester, have presented an article titled: “Automated Assessment of Keratocyte Density in Stromal Images from the ConfoScan 4 Confocal Microscope.”

The researchers from Rochester have concluded:

• “Differences in anterior stromal cell density between the ConfoScan 4 and the Tandem Scanning confocal microscopes can be explained by the different optical designs.”
• “The lower spatial resolution of the ConfoScan 4 limits its ability to resolve thin layers.”
• “The adaptation of our earlier cell-counting program to the ConfoScan 4 provides a timesaving, objective, and reproducible means of determining stromal cell densities in images from the ConfoScan 4.”

The researchers from Rochester have also noted:

• “A program was developed that used image processing routines to identify stromal cell nuclei in images from the ConfoScan 4 confocal microscope.”
• “Cell selection parameters were set to match cell densities from the program with those determined manually in 15 normal corneas of 15 volunteers.”
• “The program was tested on scans from 16 other normal volunteers and 17 volunteers 3 years after LASIK.”
• “Cell densities were compared to densities determined by manual assessment and from scans by a Tandem Scanning confocal microscope in the same corneas.”
• “Results: The difference in cell density between the automatic and manual assessment was -539 +/- 3,005 cells/mm3 (mean +/- SD, p=0.11) in the 16 test corneas.”
• “Densities estimated from the ConfoScan 4 agreed with those from the Tandem Scanning confocal microscope in all regions of the stroma except in the anterior 10%, where the ConfoScan 4 indicated a 30% lower density.”

(1) McLaren JW, Bourne WM, Patel SV: Automated Assessment of Keratocyte Density in Stromal Images from the ConfoScan 4 Confocal Microscope. Invest Ophthalmol Vis Sci. 2009 Nov 5. [Epub ahead of print]

Tags: after LASIK anterior anterior stromal cell density assessment automated automated assessment cell densities cell nuclei cell selection cell-counting compared confocal image confocal laser scanning microscopy confocal laser scanning ophthalmoscopy confocal scanning laser ophthalmoloscopy corneas densities Department of Ophthalmology Freemont image processing images keratocyte density lower density manual assessment manually match Mayo Mayo Clinic College of Medicine Minnesota NIDEK normal nuclei objective optical design parameters program reproducible resolve Reston Rochester routines scans scans after LASIK spatial resolution stromal cell nuclei stromal images thin layers timesaving Virginia volunteers

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