head_computed_tomography

Head computed tomography

Indications

Noncontrast CT scans are often employed in emergency situations (to quickly rule out most acute abnormalities), to evaluate bone in great detail, or as a screening test. It excels in demonstrating acute blood (EDH, SDH, IPH, SAH), fractures, foreign bodies, pneumocephalus, and hydrocephalus. It is weak in demonstrating acute stroke (DWI MRI is preferred), and often has poor signal quality in the posterior fossa (due to bone artifact).

IV enhanced CT scans are used primarily for imaging neoplasms or vascular malformations, especially in patients with contraindications to MRI. All CT contrast agents contain iodine. A typical IV dose of contrast: 60–65 ml o fe.g.Isovue3 00® which delivers 18–19.5 grams of iodine.

Cranial CT (CCT) scans and hospital admission are increasingly performed to rule out intracranial hemorrhage in patients after minor head injury (MHI), particularly in older patients and in those receiving antiplatelet therapy. This leads to high radiation exposure and a growing financial burden

see Canadian CT Head Rule.

see Postoperative computerized tomography.

see Computed Tomography for chronic subdural hematoma.

Repeat head computed tomography

A definitive consensus on the standardization of practice of a routine repeat head CT (RHCT) scan in patients with traumatic intracranial hemorrhage is lacking.

After mTBI, worsening of repeat head CT finding is seen in a third of patients and is associated with worse outcomes. A substantial fraction of patients who require operative intervention will have no clinical changes in the first 8 hours, supporting the value of repeat head CT within this time frame 1).

Neurologic examination can be trusted and is reliable in pediatric blunt TBI patients in determining when an RHCT scan is necessary. Aziz et al. recommend that RHCT is required routinely in patients with intracranial hemorrhage with GCS score of 8 or less and in patients with GCS greater than 8 and that RHCT be performed only when there are clinical indications 2).

Routine repeat head CT scan is not warranted in patients with normal neurologic examination. Routine repeat head CT scan does not supplement the need for neurologic examination for determining management in patients with traumatic brain injury 3).

Emergency department (ED) management of mild traumatic brain injury (TBI) with any form of traumatic intracranial hemorrhage (ICH) is variable.

Since 2000, The Department of Emergency Medicine, University of Cincinnati, Cincinnati, OH, standard practice has been to obtain a repeat head computed tomography (CT) at least 6 hours after initial imaging. Patients are eligible for discharge if clinical and CT findings are stable. Whether this practice is safe is unknown.

Discharge after a repeat head CT and brief period of observation in the ED allowed early discharge of a cohort of mild TBI patients with traumatic ICH without delayed adverse outcomes. Whether this justifies the cost and radiation exposure involved with this pattern of practice requires further study 4).

Hemorrhagic stroke

High rates of head CT use for patients with hemorrhagic stroke are frequently observed, without an association with decreased mortality. A higher number of physicians consulted was associated with high-intensity use of head CT 5).

1)
Thorson CM, Van Haren RM, Otero CA, Guarch GA, Curia E, Barrera JM, Busko AM, Namias N, Bullock MR, Livingstone AS, Proctor KG. Repeat head computed tomography after minimal brain injury identifies the need for craniotomy in the absence of neurologic change. J Trauma Acute Care Surg. 2013 Apr;74(4):967-73 ; discussion 973-5. doi: 10.1097/TA.0b013e3182877fed. PubMed PMID: 23511133.
2)
Aziz H, Rhee P, Pandit V, Ibrahim-Zada I, Kulvatunyou N, Wynne J, Zangbar B, O'Keeffe T, Tang A, Friese RS, Joseph B. Mild and moderate pediatric traumatic brain injury: replace routine repeat head computed tomography with neurologic examination. J Trauma Acute Care Surg. 2013 Oct;75(4):550-4. doi: 10.1097/TA.0b013e3182a53a77. PubMed PMID: 24064865.
3)
Joseph B, Aziz H, Pandit V, Kulvatunyou N, Hashmi A, Tang A, Sadoun M, O'Keeffe T, Vercruysse G, Green DJ, Friese RS, Rhee P. A three-year prospective study of repeat head computed tomography in patients with traumatic brain injury. J Am Coll Surg. 2014 Jul;219(1):45-51. doi: 10.1016/j.jamcollsurg.2013.12.062. Epub 2014 Mar 1. PubMed PMID: 24745622.
4)
Kreitzer N, Lyons MS, Hart K, Lindsell CJ, Chung S, Yick A, Bonomo J. Repeat neuroimaging of mild traumatic brain-injured patients with acute traumatic intracranial hemorrhage: clinical outcomes and radiographic features. Acad Emerg Med. 2014 Oct;21(10):1083-91. doi: 10.1111/acem.12479. PubMed PMID: 25308130.
5)
Bekelis K, Fisher ES, Labropoulos N, Zhou W, Skinner J. Variations in the intensive use of head CT for elderly patients with hemorrhagic stroke. Radiology. 2015 Apr;275(1):188-95. doi: 10.1148/radiol.14141362. Epub 2014 Oct 29. PubMed PMID: 25353250.
  • head_computed_tomography.txt
  • Last modified: 2020/02/06 08:27
  • by administrador