The Association Between Hyponatremia and Optic Nerve Sheath Diameter: A Prospective Study

Area of Science:

• Neurology
• Emergency Medicine
• Ophthalmology

Background:

• Hyponatremia, a common electrolyte disorder, can lead to dangerous brain edema and elevated intracranial pressure (ICP).
• Optic nerve sheath diameter (ONSD) measurement is an emerging, non-invasive method to assess ICP elevations.
• Symptomatic hyponatremia requires prompt and effective treatment to prevent neurological complications.

Purpose of the Study:

• To investigate the relationship between changes in ONSD before and after hypertonic saline treatment.
• To assess the correlation between ONSD reduction and clinical improvement in patients with symptomatic hyponatremia.
• To evaluate the utility of ONSD as a monitoring tool during hyponatremia treatment.

Main Methods:

• Prospective, self-controlled, non-randomized trial conducted in an emergency department.
• 60 patients with symptomatic hyponatremia were included.
• ONSD measurements were taken before and after treatment with hypertonic saline (3% sodium chloride), with statistical analysis using paired t-tests.

Main Results:

• A significant reduction in ONSD was observed after hypertonic saline treatment for both the right eye (5.27 mm to 4.52 mm, p<0.001) and left eye (5.26 mm to 4.53 mm, p<0.001).
• Overall mean ONSD decreased from 5.26 mm to 4.52 mm (p<0.001).
• These ONSD changes correlated with increased sodium levels and clinical improvement.

Conclusions:

• Ultrasonic measurement of ONSD is a valuable tool for monitoring clinical improvement in patients with symptomatic hyponatremia.
• Hypertonic saline therapy effectively reduces ONSD, suggesting a decrease in ICP.
• ONSD monitoring can aid in guiding treatment and assessing therapeutic response in hyponatremia management.