From the Guidelines
Yes, a CT head scan typically captures the face and orbits, but may only partially image fractures of the midface. A standard CT head examination includes imaging of the brain, skull, facial bones, and eye orbits, as noted in a study published in the Journal of the American College of Radiology in 2022 1. The orbits are routinely included because they contain important structures like the eyes, optic nerves, and extraocular muscles that may be involved in various pathologies. The facial structures are also captured, though the extent of facial coverage may vary depending on the specific protocol being used. According to the study, a head CT alone detects 95% of facial fractures, but the authors recommended a dedicated maxillofacial CT, because a head CT often only partially images fractures of the midface 1. Some institutions may perform dedicated facial or orbital CT scans when more detailed evaluation of these areas is needed. The inclusion of these structures allows radiologists to evaluate for conditions such as orbital fractures, foreign bodies, tumors, inflammatory conditions, and vascular abnormalities that may affect the eyes and surrounding structures.
- Key points to consider:
- CT head scans are useful for evaluating acute head trauma and detecting facial fractures, but may not provide detailed imaging of the midface.
- Dedicated maxillofacial CT scans may be necessary for more detailed evaluation of facial fractures.
- The incidence of concomitant intracranial injury in patients with suspected orbital wall fractures is 9%, making a contemporaneous head CT a useful diagnostic tool 1.
- In clinical practice, it is essential to consider the specific needs of each patient and to use the most appropriate imaging modality to ensure accurate diagnosis and effective treatment.
From the Research
CT Head Scan Coverage
- A CT head scan is commonly used to evaluate the brain and its surrounding structures, including the face and orbits 2.
- However, the scan's ability to capture facial fractures, particularly those in the lower third of the face and orbit, may be limited 3, 4.
Facial Fracture Detection
- Studies have shown that dedicated facial CT scans can identify additional operative fractures not detected by standard head CT scans alone 4.
- The sensitivity and specificity of brain CT for detecting facial fractures vary, with one study reporting a sensitivity of 83.72% and specificity of 98.87% 5.
- Certain types of fractures, such as nasal, midface, zygoma, and orbital fractures, may be more likely to be missed by head CT scans alone 4.
Orbit and Face Inclusion
- The orbit and face are included in the field of view of a CT head scan, but the scan's primary focus is on the brain and intracranial structures 2.
- Simultaneous head and facial CT scans may be suggested in selected patients with traumatic brain injury to assess facial fractures, including those in the orbit 3.
- A black eye can be a useful sign of facial fractures, and patients presenting with a black eye may benefit from a CT scan to rule out underlying fractures 6.