MIA 2012: Backes D, et al. Time-dependent test characteristics of head computed tomography in patients suspected of nontraumatic subarachnoid hemorrhage. Stroke. 2012 Aug;43(8):2115-9

Bottom Line ¹

100% sensitive and specific if < 6 hours from headache onset
90% sensitive if after 6 hours

A noncontrast head CT can effectively rule out atraumatic subarachnoid hemorrhage (aSAH) in patients who present with acute headache within six hours after ictus. Those who present outside this time window or present atypically for SAH (ie neck pain) require further workup, including a lumbar puncture.

(more…)

By Michelle Lin, MD|2016-11-11T18:42:23-08:00Jan 1, 2013|Neurology, Radiology|

Bottom Line ¹

Interpret this data how you will: Exposure to 2-3 CT scans of the head will triple the risk of brain tumors; 5-10 head CT scans will triple the risk of leukemia. In absolute terms, this translates into approximately 1 excess case of leukemia and 1 excess brain tumor per 10,000 patients.

(more…)

By Michelle Lin, MD|2016-11-11T18:42:23-08:00Jan 1, 2013|Pediatrics, Radiology|

Trick of the Trade: Ossification centers of the elbow

Fracture or a normal ossification center?

This is a common question heard when viewing an xray of a pediatric elbow. How do you remember the timing of normal ossification centers? FYI, the xray images above are normal and have no fractures.

(more…)

By Michelle Lin, MD|2019-01-28T22:09:10-08:00Jan 1, 2013|Pediatrics, Radiology, Tricks of the Trade|

Teaching internationally: More than just a language barrier

I recently traveled to San Salvador to help teach a pediatric and adult ultrasound course. The course was well received and it was wonderful traveling around San Salvador.

I wanted to share some of our experiences, and discuss some challenges to educating internationally. More importantly, I want to engage you, the readers to share some of your experiences when educating internationally as well.

(more…)

By Nikita Joshi, MD|2016-11-11T18:43:05-08:00Dec 7, 2012|Medical Education, Ultrasound|

Trick of the Trade: Ultrasound-guided supraclavicular central line

Subclavian central lines are commonly touted as the central line site least prone to infection and thrombosis. The problem is that they are traditionally performed without ultrasound guidance. They are done blindly because of the transducer’s difficulty in getting a good view with the clavicle in the way.

(more…)

By Michelle Lin, MD|2019-01-28T22:10:16-08:00Dec 4, 2012|Tricks of the Trade, Ultrasound|

Trick of the Trade: Sterile cover for linear ultrasound probe

You decide to use ultrasonography to help you establish peripheral IV access for and obtain blood cultures from your patient. How can you ensure that you get a sterile sampling to avoid blood culture contamination? Do you need to open a full central-line ultrasound probe cover?