Urinary system Ultrasound (Renal & Urinary bladder)

Transcription

1 Urinary system Ultrasound (Renal & Urinary bladder) Edited & Presented by ; Hussien A.B ALI DINAR. Msc.Phd ISRRT Associate Member Lecturer (National university) Reporting Sonographer (PHC)

2 Objective By the end of this lecture you should : Review Anatomy,physiology and pathology of Renal system Evaluate normal and abnormal finding in urinary system sonography Describe sonographic appearance of pathological finding

3 Anatomy The kidneys are two bean-shaped organs situated in the retroperitoneum on each side of the vertebral column. Their posterior surfaces are separated from the psoas major and the quadratus lumborum muscles by the posterior pararenal space. Each kidney consists of an upper and lower pole, anterior and posterior surfaces, a convex lateral margin and a concave medial margin. The long axis of the kidney runs obliquely and parallels the lateral border of the psoas major muscle. This means the upper poles are closer to midline than the lower poles.

4 Anatomy

5 Anatomy

6 The kidneys regulate the composition and the volume of the blood and remove wastes from the blood in the form of urine. Formation of active vitamin D. Production and secretion of erythropoietin, the hormone responsible for controlling the rate of formation of red blood cells. Production and secretion of rennin, an important enzyme in the control of blood pressure. The regulation of blood acid-base balance. (Blood PH). Functions

7 Urinalysis/Blood test and associations

8 Indications Indications for an ultrasound examination of the kidney and/or bladder include but are not limited to: Flank and/or back pain; Signs or symptoms that may be referred from the kidney and/or bladder regions such as hematuria; Abnormal laboratory values or abnormal findings on other imaging examinations suggestive of kidney and/or bladder pathology; Follow-up of known or suspected abnormalities in the kidney and/or bladder; Evaluation of suspected congenital abnormalities; Abdominal trauma; Pretransplantation and posttransplantation evaluation; and Planning and guidance for an invasive procedure

9 Scanning Protocol Transducer: MHz Patient generally supine. Right kidney: The right liver provides a good acoustic window for scanning the right kidney. The lower pole is occasionally obscured by the right colic flexure but is accessible to scanning from the posterior side. Left kidney: An acoustic window is not available for the left kidney. Scanning from the posterolateral side is advantageous as it avoids overlying gas in the colon and gastric fornix.

10 Renal sonographic Anatomy They typically measure approximately 8 13 cm in length, 2 3 cm in the anteroposterior dimension, and 4 5 cm in width. The renal sinus is central in the kidney and has an echogenic appearance. The renal cortex appears as medium-to-low level echoes surrounding the central sinus. The normal cortex should be more hypoechoic than, or isoechoic to, the liver or spleen.

11 Renal sonographic Anatomy Adult kidney Neonatal kidney

12 Renal Variants in Appearance and Location Congenital variations pelvic kidney - fails to migrate from pelvic area during embryology Dromedary hump agenesis Ectopic kidney horseshoe - isthmus of tissue that connects both kidneys Duplex kidney Hypoplastic kidney Pelvic kidney

13 Renal Variants in Appearance and Location Dromedary hump(upper) and agenesis kidneys(lower) Empty right renal fossa, caused by a partial horseshoe kidney on the left side (K). AO = aorta, V = compressed vena cava, M = lumbar muscle, L = liver

14 Renal Variants in Appearance and Location Renal hypoplasia. The absent left kidney is probably a tiny hypoplastic kidney (cursors). b Malrotated kidney at a slightly ectopic location (cursors). The renal hilum is directed anteriorly Large kidneys. a Duplex kidney (K, cursors 132.5mm) with parenchymal band, b Acromegaly (cursors 138.1mm)

15

16 SONOGRAPHY FINDING Overview and Classification of Findings : size changes: Acute diffuse diseases are generally associated with renal enlargement due to inflammatory edematous swelling, whereas chronic diseases are marked by a decrease in renal size caused by loss of parenchyma. In chronic glomerulonephritis and diabetic nephropathy, the kidneys do not shrink in size until the disease has progressed to the dialysis stage. Echogenicity changes: Increased or decreased echogenicity reflects tissue changes at the histologic level.

17 Kidney pathology finding RENAL CYSTIC DISEASE Simple Renal Cysts Sonographic criteria: Anechoic Strong back walldistal acoustic enhancement No measurable wall thickness

18 Kidney pathology finding RENAL CYSTIC DISEASE Atypical Renal Cysts Sonographic criteria: cysts may have thick walls. May contain septations. generate low levels of echogenicity from particulate matter associated with hemorrhage or infection The echogenic cyst contents may be diffuse or show dependent layering. The cyst wall may be calcified and is considered a benign finding if all other US criteria for simple cyst are met Complicated cyst with internal hemorrhage

19 Kidney pathology finding RENAL CYSTIC DISEASE Multicystic Dysplastic Kidney MCDK Sonographic criteria: kidney is large and filled with cysts of various sizes The cysts do not communicate and appear benign There is no evidence of renal parenchyma, pelvis or ureter Polycystic kidney: The kidney is enlarged and poorly defined with little evidence of residual parenchyma. A central echo complex is not visualized

20 Kidney pathology finding Hydronephrosis Hydronephrosis refers to dilatation of the renal collecting system most frequently caused by incomplete or complete obstruction. Hydroureter is dilatation of the ureter also caused by complete or incomplete obstruction Causes - In infants and children ureteropelvic junction obstruction, posterior urethralvalves in males and Prune Belly Syndrome are the most common causes of obstruction. Calculi is the most common cause in adults followed by tumors of the kidney, ureter and bladder. Less common causes are inflammatory ureteral strictures, neurogenic bladder and bladder outlet obstruction. There are three grade of hydronephrosis Grade I - renal pelvis dilated Grade II - renal pelvis & major calyces dilated Grade III - renal pelvis, major & minor calyces dilated

21 Grade 2 hydronephrosis Grade 1 hydronephrosis Grade 3 hydronephrosis

22 Kidney pathology finding Renal Calculus Disease Urolithiasis is most prevalent in males aged years.1 Calculi can form in any part of the urinary tract but most form in the kidneys. They may be clinically silent or associated with flank pain. Hematuria (gross or microscopic) and renal colic are most often associated with ureteric calculi. Stones can occur within any part of the kidneys - the renal cortex, medulla, vessels, calyces or renal pelvis.

23 Stone overview Stones in renal sinus may not be visualized due to echogenicity Stones in ureter may not be visualized due to overlying bowel gas Acoustic shadow may not be present if stone is small Stones may be visualized at the UVJ with a full bladder Renal stone Acoustic Shadow

24

25 Kidney pathology finding Cortical Nephrocalcinosis Sonographic criteria: increased corticalechogenicity which may be associated with acoustic shadowing Cortical nephrocalcinosis.

26 Medullary Nephrocalcinosis Sonographic criteria: The renal pyramids appear more echogenic than the adjacent renal cortex Pronounced medullary nephrocalcinosis: small atrophic kidney with a band of residual parenchyma and hyperechoic areas, some with acoustic shadows (S) projected over the medullary pyramids (arrows)

27 Kidney pathology finding NEOPLASMS BENIGN LESIONS Angiomyolipoma (AML) AML is a benign solid tumor containing variable amounts of blood vessels (angio), smooth muscle (myo) and fat (lipoma). Sonographic criteria: AMLs are extremely hyperechoic indicating the predominance of fat however, if muscle or vascular components predominate the lesion may be hypoechoic. Angiomyolipoma: echogenic tumor with smooth margins (arrow) causing an almost imperceptible bulge in the renal contour

28 BENIGN LESIONS Renal adenoma Sonographic criteria: Round, hypoechoic mass with smooth margins Complex internal echo pattern due to regressive changes Occasionally hyperechoic Renal adenoma

29 MALIGNANT LESIONS MALIGNANT LESIONS Renal Cell Carcinoma (RCC) is a primary tumor of the renal parenchyma thought to originate from the renal tubular epithelium. It is also called a hypernephroma or a renal adenocarcinoma Sonographic criteria: a spherical, solitary, unilateral tumor of variable size and Echogenicity renal cell carcinoma (T)

30 MALIGNANT LESIONS Nephroblastoma nephroblastoma is a rapidly growing malignant tumor of the kidneys, consisting of embryonal elements. It is also known as Wilm's tumors, Wilm's embryoma or embryonal Carcinoma Sonographic criteria: large, intrarenal, solid mass with a well-defined margin or pseudocapsule of fibrous tissue and compressed renal parenchyma. The tumor may be homogeneous or heterogeneous, if necrosis or hemorrhage has occurred. Nephroblastoma with cystic mass

31 Kidney pathology finding Renal Infections Most renal infections occur via the ascending route. They are usually caused by contaminants from the intestinal tract. Instrumentation, stasis, calculi, and vesicoureteral reflux are predisposing factors

32 Renal Infections Acute Pyelonephritis (Acute Bacterial Nephritis) Sonographic criteria: diffuse renal enlargement. decreased parenchymal echogenicity and loss of corticomedullary differentiation. The walls of the renal pelvis or major calyces may bethickened Acute pyelonephritis: Large, hypoechoic kidney with an obliterated sinus echo and a rim of fluid in the renal pelvis

33 Renal Infections Renal Abscess Sonographic criteria: renal abscess is typically a round thick walled hypoechoic complex mass with internal debris and acoustic enhancement Abscesses: anechoic cystic masses in the central echocomplex

34 Renal Infections Chronic Pyelonephritis Sonographic criteria: The affected kidney is small lobulated due to parenchymal thinning decreased renal size in pyelonephritis (83.9mm, cursors): Foci of parenchymal thinning due to scarring, producing a wavy surface contour. C = flat cyst.

35 Urinary Bladder Ultrasound The urinary bladder is a retroperitoneal organ that functions as a reservoir for urine. It is located in the pelvis, posterior to the symphysis pubis.

36 Sonographic anatomy of U.B Sonographically, the normal distended bladder appears as a smoothwalled, anechoic structure within the pelvis. In the transverse plane, it appears as a squareshaped organ; whereas in sagittal, the urinary bladder appears more elliptical.

37 Urinary Bladder pathology finding inflammation of the urinary bladder is referred to as cystitis. Inflammation of the urinary bladder will present itself sonographically as bladder wall thickening. When the bladder wall is thickened, its diameter will exceed 4 mm in a distended state

38 Urinary Bladder pathology finding A bladder diverticulum is an outpouching in the bladder wall. A diverticulum of the bladder may be associated with a urethral obstruction or it may be congenital

39 Urinary Bladder pathology finding Bladder Stones and Other Intraluminal Objects Urolithiasis may be created or become trapped within the urinary bladder. They appear as echogenic, mobile structures that produce posterior acoustic shadowing. Blood clots may also be noted within the urinary bladder. A blood clot within the bladder will appear as an echogenic, nonshadowing mass that may be mobile or adhered to the bladder wal

40 The most common malignant tumor of the bladder is TCC.Patients typically present with gross hematuria and may pass some blood clots.the sonographic appearance of TCC within the urinary bladder is a smooth or papillary hypoechoic mass that projects into the lumen of the bladder

41 Any Quiz Reference ; Thieme Clinical Companions Ultrasound EXAMINATION REVIEW FOR ULTRASOUND ABDOMEN & OBSTETRICS AND GYNECOLOGY Manual Ultrasound

42