Post-traumatic hydrocephalus, unspecified

This diagnosis describes an abnormal accumulation of cerebrospinal fluid (CSF) within the brain's ventricles that develops as a direct consequence of a traumatic brain injury (TBI). The increased CSF pressure can lead to ventricular enlargement and various neurological symptoms. It specifically refers to cases where the type of hydrocephalus (e.g., communicating, non-communicating) is not specified in the medical record.

Assign this code when documentation clearly links hydrocephalus to a preceding head trauma, and the specific type of hydrocephalus is not further detailed. This is appropriate for patients presenting with symptoms like headache, cognitive decline, gait disturbance, or incontinence following a TBI, where imaging confirms ventricular dilation. Supporting documentation includes physician notes explicitly stating "post-traumatic hydrocephalus" without further specification, along with imaging reports (CT/MRI) showing hydrocephalus.

• Ensure the documentation explicitly states a causal link between trauma and hydrocephalus; otherwise, a non-traumatic hydrocephalus code may be more appropriate.
• If the type of hydrocephalus (e.g., communicating, obstructive) is specified, use a more precise code from the G91 category.
• Always sequence this code after the acute traumatic brain injury code if the patient is still being treated for the sequelae of the initial trauma.