Central retinal venous pulsations
Diagnosing raised intracranial pressure through ophthalmoscopic examination
The ophthalmoscope is one of the most useful and underutilised tools and it rewards the practitioner with a wealth of clinical information. Through illumination and a number of lenses for magnification, the direct ophthalmoscope allows the physician to visualise the interior of the eye. Ophthalmoscopic examination is an essential component of the evaluation of patients with a range of medical conditions, including diabetes mellitus, systemic hypertension and conditions associated with raised intracranial pressure (ICP). The fundus has exceptional clinical significance because it is the only location where blood vessels can be directly observed as part of a physical examination.
Optic disc swelling and central retinal venous pulsations are useful signs in cases where raised ICP is suspected. Both signs can be obtained rapidly by clinicians who know how to recognise them. Although optic disc swelling supports the diagnosis of raised ICP, the presence of central retinal venous pulsations may indicate the contrary.
In the standard technique for direct ophthalmoscopy, the patient is positioned in a seated posture and asked to fix their gaze on a stationary point directly ahead. Pupillary dilation, removal of the patient’s spectacles and dim room illumination usually aid the examination. To start examining the patient, set the ophthalmoscope…