Thermodynamics of vitreoretinal surgery

Area of Science:

• Ophthalmology
• Surgical Technology
• Biomedical Engineering

Background:

• Vitreoretinal surgery requires precise control of the intraocular environment.
• Understanding intraocular temperature dynamics is crucial for patient safety and surgical outcomes.
• Previous studies have not extensively documented in vivo temperature variations during pars plana vitrectomy.

Purpose of the Study:

• To continuously monitor and report in vivo temperature variations within the human eye during vitreoretinal surgery.
• To quantify temperature changes in the anterior chamber, retinal surface, and vitreous cavity.

Main Methods:

• Pars plana vitrectomy was performed on 14 patients, with intraocular temperature monitored throughout.
• A custom 23-gauge thermoprobe was inserted via a sclerotomy to measure temperature.
• Temperature was recorded at baseline, during fluid infusion, epiretinal procedures, air/oil infusion, and endolaser treatment.

Main Results:

• Mean anterior chamber and retinal surface temperatures were 23.6°C and 32.3°C, respectively.
• Mean vitreous temperature decreased from 33.6°C at baseline to 26.8°C at the start and 24.8°C at the end of vitrectomy.
• Temperature increased to 29.2°C under air infusion, with statistically significant fluctuations (p < 0.001).

Conclusions:

• Vitreoretinal surgery induces significant and measurable intraocular temperature fluctuations.
• Vitreous cavity temperature decreases during simultaneous inflow and outflow, while it increases with air infusion.
• These findings highlight the importance of monitoring and managing intraocular temperature during vitreoretinal procedures.