What is Perinephric fluid?

Imaging, School of Medicine, Chung Shan Medical University. Objectives: Perinephric fluid is a critical finding of ultrasonography in daily clinical practice. The condition includes a broad spectrum of dis- eases and the fluid may arise from the kidney or adjacent retroperitoneal structures.

What is the function of perirenal fat?

Perirenal fat is mainly composed of white adipose tissue that exerts several important physiologic functions including lipid storage and the synthesis of pro-inflammatory adipokines [8].

What is Perirenal edema?

By chance, perirenal edema were discovered, and defined as high signal fluid spatters and rims surrounding the renal capsule in the perirenal fatty tissue around both kidneys (Fig. 2) in a thickness of 0.3–3.0 cm.

Is Perinephric fat stranding serious?

While a degree of symmetric bilateral perinephric stranding is common, particularly in the elderly, asymmetric or unilateral perinephric stranding is an important sign of renal inflammation or of acute obstruction. As such, it is seen in conditions such as acute pyelonephritis and with ureteric calculi.

What does stranding mean in medical terms?

This is a basic article for medical students and other non-radiologists. Fat stranding is a sign that is seen on CT. It describes the change in attenuation of fat around an inflamed structure and is a very helpful signpost for intra-abdominal pathology.

What causes Perinephric fluid?

Ultrasonography (US), computed tomography (CT), and magnetic resonance imaging (MRI) can not only show and characterize the fluid, but also may help determine the underlying cause of the perinephric fluid collection, such as ureteric obstruction, kidney injury, infection, or renal lymphangiectasia.

Why do kidneys have fat around them?

Each kidney is held in place by connective tissue, called renal fascia, and is surrounded by a thick layer of adipose tissue, called perirenal fat, which helps to protect it. A tough, fibrous, connective tissue renal capsule closely envelopes each kidney and provides support for the soft tissue that is inside.

What is bilateral pyelonephritis?

Acute pyelonephritis is a bacterial infection causing inflammation of the kidneys and is one of the most common diseases of the kidney. Pyelonephritis occurs as a complication of an ascending urinary tract infection (UTI) which spreads from the bladder to the kidneys and their collecting systems.

What do you need to know about perinephric stranding?

Perinephric stranding. Perinephric stranding refers to the appearance of edema within the fat of the perirenal space on CT or MRI. While a degree of symmetric bilateral perinephric stranding is common, particularly in the elderly, asymmetric or unilateral perinephric stranding is an important sign of renal inflammation or of acute obstruction.

When does bilateral perinephric fat stranding occur?

The bilateral perinephric stranding is a common condition that particularly occurs in the elderly, asymmetric or unilateral perinephric stranding is an important sign of renal inflammation or of acute obstruction. As such, it is seen in conditions such as acute pyelonephritis and with ureteric calculi.

Which is more common symmetric or asymmetric perinephric stranding?

While a degree of symmetric bilateral perinephric stranding is common, particularly in the elderly, asymmetric or unilateral perinephric stranding is an important sign of renal inflammation or of acute obstruction.

What causes perinephric stranding on one side of CT?

Another common cause of perinephric stranding on one side is an infection of the kidney called pyelonephritis. In these cases, a CT done with contrast will commonly show patchy areas of decreased enhancement or infection in the kidney. There may also be stranding which is an associated and sometimes not the primary finding.