Final answer:
The term 'extirpation' is the correct ICD-10-PCS root operation term for the removal of a deep left vein thrombosis, referring to the eradication of matter from a body part, such as a thrombus.
Step-by-step explanation:
In ICD-10-PCS, the term 'extirpation' refers to the removal or eradication of matter from a body part. This is the term used when a procedure is aimed at removing a space-occupying lesion such as a thrombus, abscess, or other undesirable tissue. 'Extirpation' specifically involves taking out or off a device from a body part or taking out solid matter, fluids, and/or gases from a body part. For cases related to thrombosis, like the one described, extirpation is the precise term because it involves the clearance of a thrombus from a blood vessel.
Other root operation terms like 'resection', 'removal', and 'excision' have distinct meanings. 'Resection' is typically used when an entire body part is cut out or off, 'removal' refers to taking out or off a device from a body part, and 'excision' indicates cutting out or off, without replacement, a portion of a body part.