RADIOLOGY CORNER

Military Medicine, Nov 2007 by Gage, Kelly, Sherman, Paul, James, Smirniotopoulos

Answer to last month's radiology case and image: Worst Headache of Life

Introduction: This un-enhanced brain CT scan of a 27 year old woman complaining of the worst headache of her life and nuchal rigidity was presented in last month's Radiology Corner.

Noncontrast CT scan of the head demonstrates dense subarachnoid hemorrhage in the suprasellar and basilar cisterns, as well as along the tentorium. Note the hydrocephalus demonstrated by the dilatation of the temporal horns and fourth ventricle.

Figure 1b: Noncontrast CT scan of the head at a slightly higher level shows that the hemorrhage also involves the interhemispheric fissure, sylvian fissures and insinuates within the gyri of the temporal and frontal lobes.

Patient discussion: The complaint of worst headache of life has a broad differential diagnosis, usually caused by migraines or other less serious processes. However, because 1%4% of these headaches are caused by subarachnoid hemorrhage (1), which is life threatening, patients with appropriate history and physical findings should undergo a CT scan, and if negative, a lumbar puncture.

Nontraumatic subarachnoid hemorrhage can be caused by many disease processes; however 75%-90% are caused by aneurysm rupture (2). When subarachnoid hemorrhage is found, an evaluation for the source of anurysm should follow, with either a CT angiogram (CTA), or a catheter angiogram. While catheter angiogram remains the gold standard, in some practices, CTA is gaining acceptance as the primary diagnostic modality in evaluation for aneurysm. CTA has been shown to have over 95% sensitivity for aneurysms larger than 3mm (3).

The mortality of acute subarachnoid hemorrhage is 25% in the first 24 hours, and 50% in the first 3 months. (4,5). Treatment is aimed at reducing the morbidity and mortality, primarily through preventing recurrent hemorrhage and vasospasm that often occurs after subarachnoid hemorrhage (typically within 5-10 days). Medical therapies primarily calcium channel blockers are used in an attempt to prevent vasospasm. Prevention of recurrent aneurysmal hemorrhage has traditionally required surgical clipping. More recently, endovascular treatments have become available. Although not all aneurysms are amenable to this newer treatment, for those that are amenable, endovascular treatments have been shown to be safer than open surgical treatment (6).

The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or reflecting the views of the Uniformed Services University of the Health Sciences or the Department of Defense. Reprint & Copyright

CASE # 18

The answer to this case will appear in the next issue of Military Medicine

History: A 17 year old female cheerleader reports experiencing acute left elbow pain while performing gymnastics maneuvers during recent practice sessions. The patient describes pain along the lateral aspect of the elbow and a sensation of "catching" during range of motion exercises. On physical examination, full extension of elbow was noted to cause worsening of pain and a very small joint effusion was suspected on palpation. Elbow radiography was initially obtained, followed subsequently by elbow MR imaging (Fig. 1 and 2). At the time of this case write-up, a conservative management approach had been introduced, to include rest and activity modification witii a plan for the patient to follow up for further evaluation to include consideration of arthroscopic surgery, if symptoms recur.

What is (are) the finding(s)? What is the differential diagnosis? Best diagnosis?

References:

1. Ramirez-Lassepas M, Espinosa CE, Cicer JJ, Johnston KL, Cipole RJ, Barber DL. Predictors of intracranial pathologic findings in patients who seek emergency care because of headache. Arch Neurol. 1997; 54(12): 506-9.

2. Bozzola FG, Gorelick PB, Jensen JM. Epidemiology of intracranial hemorrhage. Neuroimaging Clin N Amer. 1992; 2: 1-10.

3. White PM, Wardlaw JM, and Easton V. Can Noninvasive Imaging Accurately Depict Intracranial Aneurysms? A Systematic Review. Radiology. 2000; 217: 361-370.

4. Ingall TJ, Wiebers DO. Natural history of subarachnoid hemorrhage. In: Whisnant JP, ed. Stroke: Populations, Cohorts, and Clinical Trials. Boston, MA: Butterworth-Heinemann Ltd; 1993.

5. Adams HP, Love BB. Medical management of aneurysmal subarachnoid hemorrhage. In: Stroke: Pathophysiology, Diagnosis, and Management, 3rd ed. New York, NY: Churchill Livingstone; 1998.

6. Molyneux A, Kerr R, Stratton I, et al. International Subarachnoid Aneurysm Trial (ISAT) of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms: a randomized trial. Lancet. 2002; 360: 1267-1274.

Case provided by:

Gage, Kelly, Maj USAF , Sherman, Paul, LtCol USAF1,2, Smirniotopoulos James2 1 Wilford Hall Medical Center, 2 Uniformed Services University of the Health Sciences