Assessment of lower urinary tract function in pediatrics using ultrasonography.

Ultrasound imaging is a less invasive imaging modality without radiation exposure and is available for repeated tests. It is the gold standard examination for diagnosing and managing disorders of the urinary tract, including lower urinary tract dysfunction (LUTD) in pediatric urology. Ultrasound imaging is effective for screening underlying diseases and determining treatment strategies. Ultrasound examination at the bedside should focus on post-voided residual urine (PVR), bladder wall thickening, renal morphology, and rectal diameter. Since PVR must be tested immediately after voiding, examining infants who cannot complain of the urge to void is difficult. PVR measurement combined with a 4-h voiding observation or alarm system activated by urine is recommended for these infants. Early diagnosis is important because LUTD is associated with the risk of morbid residual urine and high voiding pressure, which can result in renal deterioration, urinary leakage, and febrile urinary tract infection.

Factors affecting testicular volume after orchiopexy for undescended testes.

PURPOSE: Children with undescended testes (UDTs) undergoing orchiopexy at a later age reportedly experience more negative effects on post-orchiopexy testicular volume (TV). This study aimed to investigate the effect of orchiopexy according to the age at operation. METHODS: We included 93 patients (127 testes) who underwent orchiopexy between 2008 and 2020. According to their age at orchiopexy, they were divided into Group 1 (< 24 months; n = 36, median follow-up: 17 [14-39] months) and Group 2 (≥ 24 months; n = 57, median follow-up: 16 [13-34] months). TV was measured with ultrasonography preoperatively and postoperatively. In unilateral UDTs, the testicular volume rates (TVR) were calculated as diseased-side TV/intact-side TV × 100%. A TVR < 50% indicated preoperative testicular atrophy (pre-op TA), whereas volume loss ≥ 50% from baseline indicated postoperative testicular atrophy (post-op TA). RESULTS: Only seven patients experienced pre-op TA. The TV of these 14 atrophic testes improved after orchiopexy (TVR: 100% (7/7) in Group 1 and 85% (6/7) in Group 2). Furthermore, the median TVR significantly improved after orchiectomy, from 27 to 58% (p < 0.01) and from 32 to 61% in Groups 1 and 2 (p < 0.05), respectively. Post-op TA was found in four testes (8%) in Group 1 and three testes (4%) in Group 2. Multivariate analysis showed that only preoperative testicular location predicted post-op TA. CONCLUSION: Post-orchiopexy TA may occur regardless of the patient's age at orchiopexy, and orchiopexy is recommended irrespective of age at diagnosis.

Effectiveness of a voiding evaluation technique using a diaper equipped with a urination-activated alarm system to assess bladder function and voiding patterns in infants.

PURPOSE: Four-hour voiding observation is a conventional method for evaluating bladder function in infants. However, it requires a diaper check every 5 min during the observation period, which creates an unusual environment for the infant, making the evaluation of natural urination difficult. This study aimed to investigate the parameters of urination before mature bladder function using a diaper equipped with a urination-activated alarm system. METHODS: The study participants were 51 infants aged 0-4 years without bladder dysfunction. A urination-activated sensor was used to notify the inspector wirelessly when urination was detected, enabling the immediate assessment of ultrasonically measured residual urine. Bladder capacity was calculated as the sum of both residual urine volume and micturition volume, and the residual urine rate as the residual urine volume divided by bladder capacity. RESULTS: A total of 36 boys and 15 girls were enrolled. The median (interquartile range) residual urine volume, bladder capacity, and residual urine rate were 3.0 mL (1.1-6.6), 53.0 mL (33.9-75.3), and 7.0% (2.1-15.0), respectively. Infants aged 0-1 and 2-4 years were then classified into Group A (N = 27) and Group B (N = 24), respectively. The residual urine rate was significantly higher in Group A (11.0% [5.4-21.2]) than in Group B (4.8% [0.6-8.9]; p < 0.01). CONCLUSIONS: Voiding observation using a urination-activated alarm system allowed less invasive analysis in infants and revealed that the residual urine rate decreased with mature bladder function from about 2 years of age.

Robot-assisted laparoscopic pyeloplasty for ureteropelvic junction obstruction due to aberrant blood vessel with ipsilateral retrocaval ureter.

INTRODUCTION: Ureteropelvic junction obstruction is a common congenital anomaly that causes hydronephrosis but rarely accompanies ipsilateral retrocaval ureter. CASE PRESENTATION: A 39-year-old woman, who visited to our hospital complaining of worsened right low back pain and fever, was diagnosed with right hydronephrosis due to ureteropelvic junction obstruction by contrast-enhanced computed tomography. Intraoperatively before the planned robot-assisted laparoscopic pyeloplasty, retrograde pyelography was performed to reveal concomitant ipsilateral retrocaval ureter. Laparoscopically, ureteropelvic junction obstruction due to aberrant blood vessel and coexisting retrocaval ureter was confirmed. Transposition of the ureter from posterior to anterior of the inferior vena cava and following dismembered pyeloplasty was performed. Two years after surgery, her right hydronephrosis improved and she had no complain of any symptom. CONCLUSION: Retrocaval ureter is a rare abnormality; however, combination of preoperative retrograde pyelography and laparoscopic evaluation was important for management of this concomitant abnormality.