To the Editor.–Carotid compression tonography1 and ocular pneumoplethysmography2 have been described as safe diagnostic procedures. However, carotid compression can rarely cause stroke or death with a combined incidence of 1/500 to 1/1500.3 We recently examined a patient who developed a fixed neurologic deficit temporally related to carotid compression tonography.
Report of a Case.–A 54-year-old right-handed man had been referred to an ophthalmologist complaining of transient blurring of vision in the right eye for two days. The right carotid artery was compressed low in the neck for six seconds during tonography. Seconds later he complained of severe right-sided headache rapidly followed by left-sided hypesthesia and left hemiplegia. One year later the left hemiplegia and left-sided sensory deficits were still evident.
Several tests that require carotid compression can be found in the literature. The impetus to develop these procedures stems from the inherent risks of carotid angiography.
Zauel D, Carlow TJ. Stroke After Carotid Compression. Arch Ophthalmol. 1977;95(3):519. doi:10.1001/archopht.1977.04450030161026