Standards of the Polish Ultrasound Society - update. Ultrasound examination of the kidneys, ureters and urinary bladder

Intra- and inter-rater reliability of post-void residual bladder volume with ultrasound

INTRODUCTION AND HYPOTHESIS

The purpose of the present study was to test the intra- and inter-rater reliability of the measurement of post-void residual bladder volume using ultrasound.

METHODS

Two evaluators performed three measurements of the height, width, and length of the empty bladder using ultrasound. The voiding residual volume was calculated using the equation: volume = length × width × height × 0.52. Intraclass correlations (ICC) were calculated considering: ICC ≥ 0.75 excellent, 0.40 ≤ ICC < 0.75 satisfactory, and ICC <0.40 poor, with a significance level of 5% and analysis of confidence intervals (95% CI).

RESULTS

Twenty women participated, with an average age of 27.95 ± 3.15 years. The inter-rater ICCs for height, width, and length were 0.96 (CI 0.89-0.98), 0.88 (CI 0.71-0.95), and 0.84 (CI0.60-0.94) respectively. For the intra-rater ICCs, the values were 0.97 (CI 0.95-0.99), 0.98 (CI 0.96-0.99), and 0.97 (CI 0.94-0.99) for evaluator 1 and 0.99 (CI 0.97-0.99), 0.97 (CI 0.94-0.99), and 0.95 (CI 0.90-0.98) for evaluator 2, for height, width, and length, respectively. The residual inter-test volume was 0.96 (CI 0.90-0.99) and the intra-test volume was 0.99 (CI 0.97-0.99). All analyses presented p < 0.0001.

CONCLUSIONS

The intra- and inter-rater reliability for both the post-void residual volume and measurement of the bladder dimensions showed excellent agreement.

Ultrasound screening for pyelectasis in pregnant women. Clinical necessity or "art for art's sake"?

Renal pelvicalyceal dilatation is caused by urine retention in the upper urinary tract. It is referred to as pyelectasis in medical literature. This term does not indicate the cause that leads to the dilatation of and urine retention in the renal pelvicalyceal system. Mild pelvicalyceal dilatation during pregnancy is usually considered to be physiological in nature – it can occur in up to 90% of pregnant women. Retention is more common in the right kidney, in primigravidae, in the second half of pregnancy and in multiple pregnancies. Pyelectasis during pregnancy rarely causes clinical symptoms and often does not require treatment. Nevertheless, urine retention in the renal pelvicalyceal system is conducive to the development of asymptomatic bacteriuria and may be a risk factor for recurrent urinary tract infections, pyelonephritis and acute kidney failure; it may also cause renal colic. In consequence, this condition can lead to intrauterine infection and premature labor in the pregnant woman and to prematurity, anemia, congenital pneumonia or sepsis in the child. In a study conducted at the 3^rd Department of Gynecology of the Medical University of Lublin it was concluded that unilateral pyelectasis of more than 20 cm³ is associated with a significant increase in the risk of asymptomatic bacteriuria. This volume corresponds to grade 3 and/or 4 pelvicalyceal dilatation according to the Society for Fetal Urology/European Federation of Societies for Ultrasound in Medicine and Biology classification. The pyelectasis volume measuring method using three-dimensional ultrasound scanning included in the criteria for the assessment of asymptomatic bacteriuria was assessed as sensitive and specific. The ultrasound-based evaluation of the kidneys for the presence of pyelectasis and its grade in pregnant women has some clinical implications. It allows for identifying cases with an increased risk of asymptomatic bacteriuria, which requires treatment in pregnant women. Screening during pregnancy for pyelectasis seems to be important in preventing asymptomatic bacteriuria from progressing to symptomatic urinary tract infection.

Kidney ultrasound - what is important for a urologist?

Kidney ultrasound is one of the basic procedures in the practice of a urologist. Apart from the location and the size, description of renal morphology should contain the thickness of the anterior lip parenchyma in a transverse section and the location of possible narrowings. Uneven outline of the kidney is a sign of past inflammatory conditions. In the case of the pelvicalyceal system dilation, it is advised to specify the dimensions of the pelvis and calyces. Convex shape of the calyces proves elevated pressure within the pelvicalyceal system. Hydronephrosis is present when urinary retention has led to thinning the renal parenchyma. In each case, one should identify the reason for urinary retention in the upper urinary tract. Urinary retention on both sides requires one to exclude urinary bladder tumor, it may also be caused by a benign prostatic hyperplasia. Ultrasound examination is a sensitive method of renal stones detection, regardless of their chemical composition. Cyst description in an ultrasound image should cover its morphological features, differentiating between the so-called simple or complex cysts. In the case of a solid lesion, ultrasound makes it possible to detect parenchymal lesions usually starting with the size of 2–2.5 cm. It enables one to particularly diagnose angiomyolipomas. As regards the remaining parenchymal lesions, differentiation of the lesion nature is impossible. In some cases of angiomyolipoma, when it contains bleeding areas present and when it is deficient in adipose tissue, it resembles adenocarcinoma. It is necessary that the description includes the exact location, especially the dimensions and relation of the tumor to the renal sinus. In the case of larger lesions, respiratory motion of the kidney, the condition of the adrenal gland and the presence of enlarged lymph nodes should be controlled. Additionally, one should evaluate the renal vein and inferior vena cava in terms of a neoplastic plug presence.

Sonography of tumors and tumor-like lesions that mimic carcinoma of the urinary bladder

One of the basic abdominal organs that is assessed during transabdominal ultrasound examination for urological reasons is the urinary bladder. The bladder must be filled with urine. This is a prerequisite for a reliable assessment and, at the same time, an acoustic window in examining adjacent structures and organs, for instance the prostate gland. In some cases, doubts occur with respect to the nature of lesions detected. The paper presents anatomic lesions, defects and pathologies which might be erroneously interpreted as tumors of the urinary bladder, i.e. transitional cell carcinoma of the urinary bladder. The following lesions are discussed: 1) anatomic defects (including urachus remnants, ligaments that stabilize the bladder or cyst in the opening of the ureter into the bladder – ureterocele); 2) tumor- like lesions in the lumen of the urinary bladder (such as blood clots, fungus balls, stones or foreign bodies); 3) bladder wall pathologies (i.e. cystitis or endometriosis), focal decidual transformation of stromal cells or inflammatory pseudotumor; 4) lesions impressing on the bladder from the outside (the mesentery of the sigmoid colon, the bowel, pathological lesions in organs adjacent to the urinary bladder, inflammatory infiltration, vasogenic compression of the bladder, pelvic lipomatosis, pathological lesions of the pubic symphysis); 5) postoperative lesions. All these lesions may mimic carcinoma of the urinary bladder in sonography. Bearing this fact in mind is significant in establishing a diagnosis. Due to the malignant character of carcinoma of the urinary bladder and the need for aggressive surgical treatment, a correct diagnosis of this disease is essential for patients, particularly because the lack of adequate treatment and delayed treatment considerably affect prognosis.

Standards of the Polish Ultrasound Society - update. Ultrasound examination of thyroid gland and ultrasound-guided thyroid biopsy

Ultrasonography is a primary imaging technique in patients with suspected thyroid disease. It allows to assess the location, size and echostructures of the thyroid gland as well as detect focal lesions, along with indication of their size, echogenicity, echostructure and vascularity. Based on these features, ultrasound examination allows to predict abnormal focal lesions for biopsy and monitor the biopsy needle track. This paper presents the standards of thyroid ultrasound examination regarding ultrasound apparatus technical requirements, scanning techniques, readings, measurements, and the description of the examination. It discusses the ultrasound features of increased malignancy risk in focal lesions (nodules) found in the thyroid gland. It presents indications for fine needle aspiration biopsy of the thyroid gland for the visibility of single nodules (focal lesions) and numerous lesions as well as discusses contraindications for thyroid biopsy. It describes the biopsy technique, possible complications and rules for post-biopsy monitoring of benign lesions. The paper is an update of the Standards of the Polish Ultrasound Society issued in 2011. It has been prepared on the basis of current literature, taking into account the information contained in the following publications: Thyroid ultrasound examination and Recommendations of the Polish Ultrasound Society for the performance of the FNAB of the thyroid.