After an elderly person suffers a head injury, they may develop unsteady gait, sluggishness, excessive sleepiness, or weakness on one side of the body two to three weeks later — a CT scan is recommended

Cost: A single cranial CT scan costs roughly 200–300 RMB.

In plain terms: After a head injury, blood usually starts accumulating only around the third week. At the time of impact, there may be absolutely no symptoms at all, and the person might not even recall the injury. The recurrence rate after surgery for this condition can reach 33%, while the mortality rate may be as high as 32%. If an elderly individual suddenly appears confused, walks unsteadily, feels unusually sleepy, or shows weakness on one side, it’s important to first ask whether they fell or hit their head in the past two to three months, then proceed with a CT scan.

Benefit: The Neurosurgical Society of the Chinese Medical Association has published a Chinese expert consensus on medical treatment for chronic subdural hematoma. This condition involves slow accumulation of blood between the meninges; technically, it refers to chronic mass formation caused by blood buildup between the arachnoid membrane and dura mater. It “typically develops three weeks after head trauma” and is most common among older adults. Post-surgery recurrence and mortality rates can reach 33% and 32% respectively. Among patients aged 90 or older, only 24% achieve a satisfactory recovery overall. Global data shows that incidence rates range from 3.39 to 39.1 new cases per 100,000 people annually, rising sharply after age 80. The most common causes are trauma and falls, followed by chronic alcohol consumption, use of anticoagulant medications, and violent injury. Geriatric literature notes that typical symptoms include confusion, cognitive decline, gait disturbances, and excessive sleepiness — features that may overlap with other geriatric syndromes.

Evidence grade: B

Sources:Zhang J 等 (2021). Expert consensus on drug treatment of chronic subdural hematoma. Chinese Neurosurgical Journal, 7(1), 47. https://doi.org/10.1186/s41016-021-00263-z ; Dziho A 等 (2025). Global prevalence and incidence of chronic subdural hematoma: A systematic review. Brain and Spine, 5, 105893. https://doi.org/10.1016/j.bas.2025.105893 ; Mathon B, Shotar E (2026). Diagnostic and therapeutic management of chronic subdural hematoma in elderly patients. Gériatrie et Psychologie Neuropsychiatrie du Vieillissement, 24(1), 30-41. https://doi.org/10.1684/pnv.2026.1274

Notes: At the time of injury, there may be absolutely no symptoms, and the elderly person might not even recall the incident. Therefore, when families notice sudden confusion, unsteady walking, excessive sleepiness, or unilateral weakness, they should first check whether a head injury occurred in the past two to three months before ordering a CT scan. It’s crucial not to automatically attribute these symptoms to “senile dementia” or “post-stroke sequelae,” as doing so could lead to delayed diagnosis. Elderly individuals taking aspirin, clopidogrel, warfarin, or newer oral anticoagulants face higher risks, as does long-term heavy alcohol consumption. For fall prevention, refer to Section 1, Item 13 — focusing on balance training and leg strength exercises.