Week 4

Being sick in New York was an unpleasant experience – but an unfortunate part of my week. Between that, and the 4^th of July, there wasn’t as much available to me this week clinically (I had originally planned to attend rounds and an M&M meeting in the earlier part of the week but was unable to due to illness). When I managed to make it back into the hospital for Thursday, all I had planned for that day was data collection from image analysis, which, while a necessary component of my research project, is not necessarily a blog worthy addition

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In light of a traditional blog post, I figured a good exercise for myself would be to summarize some of the findings on CT-guided lung biopsies and how they are performed.

Like any biopsy, the percutaneous lung biopsies will only be ordered after an initial image/consultation. As a relevant example, I’ve been able to see the Lung Cancer Screening program here at the hospital, where patients within a certain at risk demographic (high pack-year smokers/former smokers) can come in for screenings and initial consultations (I’ve been fortunate enough to sit in on one of these in previous weeks).

In the interventional radiology department, procedures are generally performed under CT fluoroscopy with what is referred to as “quick check” methodology, ie, periodic imaging/movement of the biopsy needle in response to the image, so as to not overexpose either the patient or the clinician to unneeded x-rays¹. To guide the needle accurately, a grid is placed atop the patient (who, in most cases, will be sitting in a prone position to reduce anxiety).

These procedures are all generally performed using a coaxial needle at New York Presbyterian, which reduces the number of punctures. This coaxial needle is a larger needle used to guide the biopsy probe. Two types of biopsies can be performed, depending on the intention of the operator: a fine needle aspiration, and a core biopsy. These procedures have various benefits (risk of pneumothorax, hemorrhaging, false positive/negative rates)² and, in the scope of the literature, appear to be an operator dependent decision.

Pneumothorax, as previously mentioned throughout my blog posts, is the most common complication of these surgeries. The factors that are known to affect it are frequently disputed, with reports of lesion depth, lesion size, etc, showing either no correlation or a correlation depending on the institution of origin².

The second most common complication is hemorrhaging. Of particular interest to me is that it can actually lower the risk of pneumothorax! As the blood surrounds the biopsy needle, it seals the tract, and prevents the outside pressure from acting against the lung.

With all that listed down, I’m optimistic that next week’s post will have more clinical details – it seems unlikely that I’ll be sick two weeks in a row!

1 - Paulson E K, Sheafor D H, Enterline D S, McAdams H P, Yoshizumi T T. CT fluoroscopy—guided interventional procedures: techniques and radiation dose to radiologists. Radiology. 2001;220(1):161–167.

2 - Winokur RS, Pua BB, Sullivan BW, Madoff DC. Percutaneous lung biopsy: technique, efficacy, and complications. Semin Intervent Radiol. 2013;30(2):121–127.