The posterior intercostal approach for percutaneous renal procedures: risk of puncturing the lung, spleen, and liver as determined by CT.

A posterior intercostal approach is commonly used for percutaneous access to the upper poles of the kidney. However, the safety of this approach with respect to puncturing the intervening lung, pleura, liver, and spleen with the needle has been inferred only from a small series of patients without regard to the degree of respiration. To determine the possibility of puncturing these structures, we performed CT at both maximal inspiration and expiration and with sagittal reconstructions in 43 (27 supine and 16 prone) randomly selected patients. With expiration, the needle path was such that there was little risk to the spleen and liver from an 11th-12th posterior intercostal approach. However, the chance of transgressing the lung with this approach to the kidney was 29% on the right and 14% on the left. If done during maximal inspiration, the lung would be in the path of the needle in most patients. With a 10th-11th rib posterior intercostal approach, the chance of puncturing the lung was excessive regardless of the degree of respiration used. Our results show that the primary risk from a posterior 11th-12th rib intercostal approach to the upper renal collecting system is puncture of intervening lung, a complication that can be expected to occur in from 14% to 29% of patients. The risks from a posterior 10th-11th rib intercostal approach appear prohibitive.