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Difference in ocular surface temperature by infrared thermography in phakic and pseudophakic patients.

Sniegowski M, Erlanger M, Velez-Montoya R, Olson JL - Clin Ophthalmol (2015)

Bottom Line: There were no statistical differences among the study groups (P=0.3).There was a nonsignificant negative correlation trend between age and surface temperature in the phakic group.Although cataract extraction and intraocular lens implantation seem to induce a mild increase in ocular surface temperature, the effect is not clear and not significant.

View Article: PubMed Central - PubMed

Affiliation: Ophthalmology Department, University of Colorado School of Medicine, Rocky Mountain Lions Eye Institute, Aurora, CO, USA.

ABSTRACT

Purpose: To assess the change in ocular surface temperature between healthy phakic and pseudophakic patients.

Methods: We included patients with no history of ocular disease other than cataract. Patients were divided into three groups: clear lens, cataract, and pseudophakic. All patients had two ocular surface digital thermal scans. An average of five surface points was used as the mean ocular surface temperature. Results were analyzed with a one-way analysis of variance and a Tukey's least significance difference test. The patients were further divided into phakic and pseudophakic groups. Correlation coefficients between several variables were done in order to assess dependencies.

Results: Fifty-six eyes (28 cataracts, 12 clear lenses, 16 pseudophakic) were enrolled. The mean ocular surface temperature in the cataract group was 34.14°C±1.51°C; clear lens: 34.43°C±2.27°C; and pseudophakic: 34.97°C±1.57°C. There were no statistical differences among the study groups (P=0.3). There was a nonsignificant negative correlation trend between age and surface temperature in the phakic group. The trend inverted in the pseudophakic group but without statistical significance.

Conclusion: Although cataract extraction and intraocular lens implantation seem to induce a mild increase in ocular surface temperature, the effect is not clear and not significant.

No MeSH data available.


Related in: MedlinePlus

Digital thermal image from a representative patient.Notes: The cursor is placed in the center and then moved around into five different positions of the corneal surface. The process is repeated twice per eye. The left eye depicts the five zones from where every measurement was taken.Abbreviations: S, superior; I, inferior; N, nasal; T, temporal; 1 mm, central cornea 1 mm.
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f1-opth-9-461: Digital thermal image from a representative patient.Notes: The cursor is placed in the center and then moved around into five different positions of the corneal surface. The process is repeated twice per eye. The left eye depicts the five zones from where every measurement was taken.Abbreviations: S, superior; I, inferior; N, nasal; T, temporal; 1 mm, central cornea 1 mm.

Mentions: All patients were acclimated to the clinical environment for at least 15 minutes. The room temperature was specifically set and controlled at all times at 22°C (≈72°F), humidity was maintained at 42.0%, and the average indoor illumination was maintained at 300 lux. Two thermal scans of each subjects orbits and bilateral ocular surfaces were taken by using a FLIR® T420 Thermal digital camera with thermal digital enhancement (FLIR Systems Inc., Boston, MA, USA), with an accuracy of ±2%; thermal sensitivity of <0.045°C; temperature range of −20°C to 650°C; resolution of 76,800 pixels (320×240) and frame rate of 60 Hz. We calibrated the system before each scan by scanning a heated pad of known/controlled temperature, and the test was always performed between 9:00 am and 11:30 am to avoid daily temperature variations. Patients were comfortably seated 50 cm away from the camera. Patients were asked to blink normally for a few seconds and then to open their eyes as wide as possible as the scan was obtained. The process was repeated twice. The image acquisition was nearly instantaneous; thermal density was plotted on a color scale from deep blue to brown red, passing by cyan blue, green, yellow orange, and red, representing from low to high temperatures (Figure 1).


Difference in ocular surface temperature by infrared thermography in phakic and pseudophakic patients.

Sniegowski M, Erlanger M, Velez-Montoya R, Olson JL - Clin Ophthalmol (2015)

Digital thermal image from a representative patient.Notes: The cursor is placed in the center and then moved around into five different positions of the corneal surface. The process is repeated twice per eye. The left eye depicts the five zones from where every measurement was taken.Abbreviations: S, superior; I, inferior; N, nasal; T, temporal; 1 mm, central cornea 1 mm.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4358693&req=5

f1-opth-9-461: Digital thermal image from a representative patient.Notes: The cursor is placed in the center and then moved around into five different positions of the corneal surface. The process is repeated twice per eye. The left eye depicts the five zones from where every measurement was taken.Abbreviations: S, superior; I, inferior; N, nasal; T, temporal; 1 mm, central cornea 1 mm.
Mentions: All patients were acclimated to the clinical environment for at least 15 minutes. The room temperature was specifically set and controlled at all times at 22°C (≈72°F), humidity was maintained at 42.0%, and the average indoor illumination was maintained at 300 lux. Two thermal scans of each subjects orbits and bilateral ocular surfaces were taken by using a FLIR® T420 Thermal digital camera with thermal digital enhancement (FLIR Systems Inc., Boston, MA, USA), with an accuracy of ±2%; thermal sensitivity of <0.045°C; temperature range of −20°C to 650°C; resolution of 76,800 pixels (320×240) and frame rate of 60 Hz. We calibrated the system before each scan by scanning a heated pad of known/controlled temperature, and the test was always performed between 9:00 am and 11:30 am to avoid daily temperature variations. Patients were comfortably seated 50 cm away from the camera. Patients were asked to blink normally for a few seconds and then to open their eyes as wide as possible as the scan was obtained. The process was repeated twice. The image acquisition was nearly instantaneous; thermal density was plotted on a color scale from deep blue to brown red, passing by cyan blue, green, yellow orange, and red, representing from low to high temperatures (Figure 1).

Bottom Line: There were no statistical differences among the study groups (P=0.3).There was a nonsignificant negative correlation trend between age and surface temperature in the phakic group.Although cataract extraction and intraocular lens implantation seem to induce a mild increase in ocular surface temperature, the effect is not clear and not significant.

View Article: PubMed Central - PubMed

Affiliation: Ophthalmology Department, University of Colorado School of Medicine, Rocky Mountain Lions Eye Institute, Aurora, CO, USA.

ABSTRACT

Purpose: To assess the change in ocular surface temperature between healthy phakic and pseudophakic patients.

Methods: We included patients with no history of ocular disease other than cataract. Patients were divided into three groups: clear lens, cataract, and pseudophakic. All patients had two ocular surface digital thermal scans. An average of five surface points was used as the mean ocular surface temperature. Results were analyzed with a one-way analysis of variance and a Tukey's least significance difference test. The patients were further divided into phakic and pseudophakic groups. Correlation coefficients between several variables were done in order to assess dependencies.

Results: Fifty-six eyes (28 cataracts, 12 clear lenses, 16 pseudophakic) were enrolled. The mean ocular surface temperature in the cataract group was 34.14°C±1.51°C; clear lens: 34.43°C±2.27°C; and pseudophakic: 34.97°C±1.57°C. There were no statistical differences among the study groups (P=0.3). There was a nonsignificant negative correlation trend between age and surface temperature in the phakic group. The trend inverted in the pseudophakic group but without statistical significance.

Conclusion: Although cataract extraction and intraocular lens implantation seem to induce a mild increase in ocular surface temperature, the effect is not clear and not significant.

No MeSH data available.


Related in: MedlinePlus