The hepatorenal recess (“Morison’s pouch”) is a potential space between the liver and right kidney. With small volumes of intraabdominal blood (hemoperitoneum), ascites, or even peritoneal dialysis, fluid accumulates in this recess which shows up as a near-black stripe on ultrasound. This video shows Morison’s pouch containing no discernible fluid collection.
In the video above, the patient’s head is on the left and feet are on the right. The liver is the large structure occupying most of the left ultrasound field. You can make out the elliptical right kidney tissue and note the echogenic renal pelvis. Note how there’s a smooth, seamless transition between the liver and kidney tissue. This is where I often see fluid (usually black-gray depending on its composition) in the aforementioned conditions.
Drop me a comment below with questions! 🙂
can you please indicate the exact site of the hepatorenal recess filled with fluid. Is it grey or black. what is its thickness in the sonography here?
Hey Efama, I’ve added labels to clarify the anatomy in the ultrasound clip. In this example, there is NOT any obvious fluid collection in the hepatorenal recess.