15.2 Bladder & Prostate

ARRT Sonography Primary

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1 Introduction & Exam Overview

1.1 Current Exam Facts & Logistics 1.2 Scoring, Section Minimums & the August 2026 Cut-Score Change 1.3 Official Blueprint & Study Strategy

2 Patient Care: Ethics, Legal Practice & Communication

2.1 Ethical & Legal Aspects of Patient Care 2.2 Interpersonal Communication & Patient Education 2.3 Physical Assistance, Monitoring & Sonographer Ergonomics

3 Patient Care: Safety, Emergencies & Infection Control

3.1 Medical Emergencies & Critical Findings 3.2 Infection Control & Hazardous Materials 3.3 Ultrasound Safety & Interventional Procedure Care

4 Image Production: Transducers & the Ultrasound Beam

4.1 Piezoelectric Effect & Transducer Construction 4.2 Beam Configuration: Near Field, Far Field & Focus 4.3 Transducer Types, Selection, Care & Malfunctions

5 Image Production: Pulse Characteristics & Resolution

5.1 Pulse Characteristics: PRF, PRP, SPL & Duty Factor 5.2 Resolution: Axial, Lateral, Temporal, Elevational & Contrast 5.3 Frequency, Bandwidth, Q Factor, Power, Pressure, Intensity & Amplitude

6 Image Production: Imaging Modes & Doppler Principles

6.1 B-Mode & M-Mode Imaging 6.2 Spectral Doppler: Pulsed Wave vs Continuous Wave 6.3 Color Doppler & Power Doppler

7 Image Production: Optimization Controls

7.1 Power, Gain, TGC, Depth & Focal Zone 7.2 Frame Rate, Line Density, Dynamic Range, Harmonics & Compounding 7.3 Doppler Optimization Controls

8 Image Production: Sound–Tissue Interactions

8.1 Speed of Sound & the Range Equation 8.2 Acoustic Impedance, Reflection, Refraction & Scattering 8.3 Attenuation, Absorption & Intensity

9 Image Production: Signal Processing, Display & Bioeffects

9.1 Receiver, Signal Processing & Analog-Digital Conversion 9.2 Postprocessing, Magnification, Panoramic & 3D/4D Imaging 9.3 Bioeffects & Output Display Measures

10 Image Production: Image Evaluation & Artifacts

10.1 Criteria for Diagnostic Quality & Annotation 10.2 Grayscale Artifacts 10.3 Doppler Artifacts

11 Image Production: Real-Time Interpretation & Informatics

11.1 Real-Time Imaging, Echogenicity & Echotexture 11.2 Color & Spectral Analysis: Measurements and Waveforms 11.3 Imaging Informatics: HIS, RIS, EMR, PACS & DICOM

12 Procedures: Abdominal & Transplant Vasculature

12.1 Aorta, Its Branches & the IVC 12.2 Portal Venous System & Hepatic Vasculature 12.3 Liver & Renal Transplant Sonography

13 Procedures: Liver

13.1 Liver Anatomy, Variants & Examination Technique 13.2 Diffuse Liver Disease 13.3 Focal Liver Lesions

14 Procedures: Biliary System, Pancreas & Spleen

14.1 Gallbladder & Bile Ducts 14.2 Pancreas 14.3 Spleen

15 Procedures: Urinary Tract, GI Tract & Other Abdominal Structures

15.1 Kidneys & Ureters 15.2 Bladder & Prostate 15.3 GI Tract, Adrenals, Lymph Nodes, Hernias & Peritoneal Cavity

16 Procedures: First-Trimester Obstetrics

16.1 Early Gestation: Normal Development & Structures 16.2 First-Trimester Measurements, Dating & Maternal Anatomy 16.3 First-Trimester Abnormalities

17 Procedures: Second/Third-Trimester Biometry & Fetal Survey

17.1 Standard Biometry: BPD, HC, AC, FL & Growth Assessment 17.2 Fetal Anatomic Survey: Head, CNS, Face & Spine 17.3 Fetal Anatomic Survey: Heart, Chest, GI, GU, Skeleton & Fetal Position

18 Procedures: Chromosomal, Genetic & Structural Abnormalities

18.1 Chromosomal & Genetic Abnormalities 18.2 Major Structural Anomalies by System 18.3 Fetal Infection, Neoplasms & Hydrops

19 Procedures: Placenta, Amniotic Fluid, Cord & Cervix

19.1 Placenta: Normal, Previa, Abruption & Accreta 19.2 Amniotic Fluid Assessment & Growth Disorders 19.3 Umbilical Cord & Cervical Assessment

20 Procedures: Fetal Assessment, Doppler & Multiple Gestation

20.1 Biophysical Profile & Fetal Surveillance 20.2 Fetal & Uteroplacental Doppler 20.3 Multiple Gestations, Assisted Reproduction & Maternal Disease

21 Procedures: Gynecology — Uterus

21.1 Uterine Anatomy, Myometrium & Fibroids 21.2 Endometrium: Cyclic Changes, Hyperplasia & Cancer 21.3 Cervix & Congenital Uterine Anomalies

22 Procedures: Gynecology — Adnexa & Pelvis

22.1 Ovaries: Normal, Functional Cysts & Benign Masses 22.2 Ovarian Malignancy, Torsion & Fallopian Tubes 22.3 Cul-de-Sac, Vagina & Pelvic Floor

23 Procedures: Neck & Scrotum

23.1 Thyroid & Parathyroid 23.2 Salivary Glands & Neck Lymph Nodes 23.3 Scrotum & Testes

24 Procedures: Breast & Peripheral Vascular

24.1 Breast & Axilla 24.2 Venous Extremity Doppler 24.3 Carotid Doppler & Post-Catheterization Complications

25 Procedures: Pediatric, Interventional & Miscellaneous

25.1 Neonatal Head, Spine & Hip Sonography 25.2 Pediatric GI & Noncardiac Chest 25.3 Ultrasound-Guided Interventions, MSK & Superficial Masses

15.2 Bladder & Prostate

Key Takeaways Explain This Topic AI

A distended bladder displaces bowel and provides the acoustic window for the bladder wall, distal ureters, prostate, and pelvic organs

Bladder wall thickness should measure less than about 3 mm when fully distended; trabeculation reflects detrusor hypertrophy from chronic outlet obstruction

Transitional cell carcinoma appears as a fixed, nonmobile, vascular soft-tissue mass projecting into the lumen, unlike mobile stones or clot

Bladder or prostate volume is estimated with the prolate ellipse formula: length x width x height x 0.523

Benign prostatic hyperplasia enlarges the transition zone, and an enlarged median lobe protruding into the bladder base can mimic a bladder mass

Last updated: July 2026

Bladder Technique and Normal Appearance

Transabdominal bladder sonography depends on a distended bladder as an acoustic window. Have the patient drink roughly 1 liter (about 32 ounces) of water 30-60 minutes before the examination and refrain from voiding. The full bladder displaces gas-filled bowel out of the pelvis and allows evaluation of the bladder wall, the distal ureters and ureterovesical junctions, the prostate, and the uterus and adnexa. Scan suprapubically in transverse and sagittal planes with a 2-5 MHz curvilinear transducer; reduce overall gain so the urine stays anechoic and subtle wall lesions are not washed out.

Normal urine is echo-free and the wall is thin and smooth. Bladder wall thickness should measure less than about 3 mm when the bladder is well distended and under roughly 5 mm when empty. This distention caveat matters: an underfilled bladder makes the wall appear spuriously thickened and can hide small lesions, while overdistention is uncomfortable and can trigger vasovagal symptoms. Before declaring wall thickening pathologic, confirm the bladder was adequately full. Document three orthogonal dimensions, wall character, any focal lesion with size and vascularity, and - when obstruction is suspected - the presence and symmetry of ureteral jets at the trigone with color Doppler. Trabeculation is a thickened, irregular, undulating wall produced by detrusor muscle hypertrophy from chronic bladder outlet obstruction - most often benign prostatic hyperplasia in men or a neurogenic bladder. With long-standing obstruction, small outpouchings called cellules develop between trabeculae and may progress to true diverticula.

Bladder Pathology

Stones - echogenic, mobile foci that layer in the dependent portion of the bladder and usually cast an acoustic shadow; they may form around foreign bodies or suture material

Diverticula - sac-like outpouchings through the detrusor; demonstrate the neck connecting the diverticulum to the lumen, watch it empty after voiding, and search inside for stones or tumor, since stagnant urine raises the risk of both. A Hutch diverticulum is a congenital type occurring adjacent to the ureterovesical junction, while most acquired diverticula arise from chronic outlet obstruction

Cystitis - diffuse or focal wall thickening; emphysematous cystitis in diabetic patients shows echogenic gas foci with dirty shadowing or reverberation in the wall, while hemorrhagic cystitis fills the lumen with echogenic clot and debris. An indwelling catheter balloon appears as a round fluid-filled structure and should not be misread as a cystic mass

Transitional cell carcinoma (TCC) - the most common bladder malignancy; appears as a fixed, polypoid or frond-like soft-tissue mass projecting into the lumen or as focal asymmetric wall thickening. TCC does not move with repositioning and often shows internal vascularity on color Doppler, features that separate it from mobile stones and avascular clot. Risk factors include smoking and industrial chemical exposure, and painless hematuria is the classic presentation

Post-Void Residual and Bladder Volume

Bladder volume is estimated with the prolate ellipse formula: length x width x height x 0.523 , using the three maximal orthogonal dimensions. The post-void residual (PVR) is the volume remaining immediately after voiding. A PVR above roughly 100 mL is abnormal and suggests urinary retention from outlet obstruction, detrusor underactivity, or neurogenic bladder; serial PVR measurements are used to follow treatment. Measure quickly after voiding, because urine refills the bladder at 1-2 mL per minute. The same formula also estimates pre-void bladder volume when a protocol calls for documenting how full the bladder was during the pelvic survey.

Prostate

The prostate is assessed transabdominally through the distended bladder as a chestnut-shaped gland at the bladder base , inferior to the trigone and surrounding the proximal urethra. In benign prostatic hyperplasia (BPH) , the transition (central) zone enlarges, producing a bulky, often heterogeneous gland. An enlarged median lobe protruding into the bladder base elevates the bladder floor and can mimic an intrinsic bladder mass - recognize its continuity with the prostate below. Prostate volume uses the same 0.523 formula; the normal gland is about 20-25 mL , and volumes above 30-40 mL indicate enlargement. The gland is divided into the central transition zone , the outer peripheral zone where most cancers arise, and a small central zone around the ejaculatory ducts. Transabdominal imaging estimates size and detects median-lobe protrusion and residual urine, but it cannot reliably exclude carcinoma ; transrectal ultrasound (TRUS) provides the zonal detail needed to find the typically hypoechoic peripheral-zone tumors and to guide biopsy.

Ureteroceles

A ureterocele is a congenital cystic dilation of the distal submucosal ureter that balloons into the bladder at the ureterovesical junction. Sonographically it is a thin-walled, round cystic structure within the posterolateral bladder that may be seen to fill and empty as the ureter peristalses, producing the classic cobra-head appearance on contrast studies. In children, an ectopic ureterocele is strongly associated with a duplicated collecting system , where it drains the obstructed upper-pole moiety; the simple (orthotopic) type occurs in adults with a single system. Stones may form inside a ureterocele, and large ones can obstruct the bladder outlet or prolapse into the urethra. When a cystic structure is found at the trigone, always scan the ipsilateral kidney for duplication and hydronephrosis.