Transvaginal color Doppler sonography of the ureteral jets: a method to detect ureteral patency

"From the tip to the deep of the iceberg": Parametrial involvement in endometriosis

Deep endometriosis (DE) can be localized in the parametrium, a complex bilateral anatomical structure, sometimes necessitating intricate surgical intervention due to the potential involvement of autonomic nerves, uterine artery, and ureter. If endometriotic ovarian cysts have been considered metaphorically representative of "the tip of the iceberg" concerning concealed DE lesions, it is reasonable to assert that parametrial lesions should be construed as the most profound region of this iceberg. Also, based on a subdual clinical presentation, a comprehensive diagnostic parametrial evaluation becomes imperative to strategize optimal management for patients with suspected DE. Recently, the ULTRAPARAMETRENDO studies aimed to evaluate the role of transvaginal ultrasound for parametrial endometriosis, showing distinctive features, such as a mild hypoechoic appearance, starry morphology, irregular margins, and limited vascularization. The impact of medical therapy on parametrial lesions has not been described in the current literature, primarily due to the lack of adequate detection at imaging. The extension of DE into the parametrium poses significant challenges during the surgical approach, thereby increasing the risk of intra- and postoperative complications, mainly if performed by centers with low expertise and following multiple surgical procedures where parametrial involvement has gone unrecognized. Over time, the principles of nerve-sparing surgery have been incorporated into the surgical DE treatment to minimize iatrogenic damage and potentially reduce the risk of functional complications.

Detection of distal ureteral stones in pregnancy using transvaginal ultrasound

AIMS

To determine the performance of transvaginal ultrasound for the visualization of distal ureteral stones in pregnant patients with renal colic and to evaluate the diagnostic value of secondary findings suggestive of obstructing ureteral stone disease.

METHODS

We retrospectively identified 129 pregnant patients with a total of 142 encounters with both abdominal and transvaginal ultrasound. Ultrasound images for each patient were reviewed recording the presence of stone with location, hydronephrosis, resistive indices (RI), and status of the ureteral jets. Patients were subcategorized into two groups based on the visualization of distal ureteral stone.

RESULTS

The transvaginal technique identified 94% (N = 16/17) of sonographically detected stones in the distal ureter/urethra, while the transabdominal technique identified 29% (N = 5/17). The combined imaging for initial assessment of renal colic in pregnancy demonstrated a sensitivity of 89%, specificity 100%, and negative predictive value (NPV) of 98%. The frequency of hydronephrosis was statistically greater in the visualized stone group (94% vs 51%). Mean RI was identical in both groups however the delta RI was significantly elevated in those patients with distal ureteral stones with a mean delta RI value of 0.05. The rate of absence of ureteral jets was not statistically significant.

CONCLUSION

The present data would suggest a utility of transvaginal ultrasound for the evaluation of the pregnant patient with 94% of distal stones being detected transvaginal versus 29% transabdominally. Additionally, there was significantly increased hydronephrosis and elevated RIs in patients with distal ureteral stones.

Evaluation of the ureteral jet in dogs by using color Doppler ultrasonography

Ureteral jets are the result of a forceful ejection of urine from the vesicoureteral junction into the urinary bladder. By using color Doppler ultrasonography (US), we aimed to identify distinct ureteral jets in dogs, provide insight into ureteral obstruction, and facilitate study of urodynamics and vesicoureteric sphincter function via pulsed Doppler US. Color Doppler US was applied to detect urinary flow from the right ureteral orifices in eight healthy beagles. Under anesthesia, 0.9% saline (2.5 mL/kg/h) and furosemide (0.5 mg/kg) were administered intravenously to assist in detection of distinct ureteral jets and examine their frequency, velocity, duration, and waveform. In all dogs, ureteral jets were visualized under diuresis and anesthesia within 2 to 5 min (mean 3.57 ± 0.90 min) of the furosemide injection. Mean frequency, peak velocity, and duration of right ureteral jets in seven dogs in whom six ureteral jet waveform patterns were identified were 9.86 ± 3.09 jets/min, 34.07 ± 10.02 cm/sec, and 2.82 ± 1.08 sec, respectively. During the 10 min period starting 10 min after the initial jet appeared, only three waveforms were identified. Color Doppler US of ureteral jets may aid in assessing vesicoureteric sphincter function and ureteral abnormalities, such as ureteral obstruction, in dogs.

Visualization of ureters on standard gynecological transvaginal scan: a feasibility study

OBJECTIVE

To investigate the feasibility of identifying pelvic segments of normal ureters and measuring their size on standard transvaginal ultrasound examination.

METHODS

This was a prospective observational study from June to July 2012. All women in the study underwent a transvaginal ultrasound examination performed for various indications either by an expert or by an intermediate-level operator. A standardized assessment of the pelvic organs was performed, recording any congenital or acquired uterine pathology and ovarian abnormalities. Visualization of pelvic segments of both ureters was attempted in all cases. The success in finding the ureters, the time required to identify them and their dimensions at rest and while exhibiting peristalsis were all recorded.

RESULTS

A total of 245 consecutive women were included in the study. In all women at least one ureter was successfully identified. Both ureters were seen in 227 women (92.7% (95% CI, 89.4-96.0%)). In 17 (6.9% (95% CI, 3.7-10.1%)) the left ureter was not seen and in one woman (0.4% (95% CI, 0.0-1.2%)) the right ureter could not be visualized (P < 0.001). There were no significant differences in the median time required to visualize the right and left ureters (9.0 (interquartile range (IQR), 6.0-14.0) s vs 8.0 (IQR, 6.0 -14.0) s, respectively; P = 0.9). The median diameter of the right ureter was 1.7 (IQR, 1.4-2.2) mm at rest and 2.9 (IQR, 2.4-3.6) mm during peristalsis. The median diameter of the left ureter was 1.9 (IQR, 1.6-2.3) mm at rest and 2.9 (IQR, 2.4-3.6) mm during peristalsis.

CONCLUSION

Pelvic segments of normal ureters can be identified in most women on transvaginal ultrasound examination. Visualization of the ureters could be integrated into the routine pelvic ultrasound examination, particularly in women presenting with pelvic pain or in those with suspected pelvic endometriosis.

An evaluation of ureteral flow after doppler-guided uterine artery occlusion device placement during organ-preserving gynecologic procedures

We studied the use of color Doppler ultrasonography for ureteral patency after placement of a transvaginal Doppler-guided uterine artery occlusion device before organ-preserving surgery for leiomyomata uteri. Our case series involved 7 patients in whom ureteral flow was assessed using color Doppler sonography before and after placement of a Doppler-guided uterine artery occlusion device. Bilateral ureteral flow was assessed at the trigone using a grading system. Furosemide and additional intravenous hydration were administered if no flow was observed. Color Doppler ultrasonography can quantify ureteral flow before and after Doppler-guided uterine artery occlusion device placement during organ-preserving gynecologic procedures, facilitating safe placement and repositioning of the transvaginal device when necessary.

Diagnostic accuracy of color Doppler sonographic study of the ureteric jets in evaluation of hydronephrosis

OBJECTIVE

Hydronephrosis (HN) and obstruction are closely associated, but upper urinary tract dilatation can occur without significant obstruction. Despite some pitfalls, conventional ultrasonography and diuretic renography (DR) are the main means of evaluation of HN in children. Recent reports have demonstrated color Doppler ultrasonography (CDUS) to reliably identify ureteric jets in the bladder. The aim of this study was to evaluate this method as a diagnostic tool to distinguish obstructive from non-obstructive dilatations of the upper tract.

METHODS

We evaluated 51 patients (37 boys and 14 girls), aged 3 months to 14 years (median 4 years), who presented with unilateral grade III and IV hydronephrosis with suspicion of pyeloureteral junction obstruction. All patients underwent DR and evaluation of ureteric jets by transverse CDSG of the bladder within a maximum of 2 weeks. Obstruction was considered in the DR when the hydronephrotic unit showed a differential renal function of less than 40%, or when symptomatic intermittent renal colic was present in older children. The number of ureteric jets was counted over a 5-min period and the frequency calculated for each ureteral orifice. Relative jet frequency (RJF) was defined as frequency of the hydronephrotic side divided by total ureteric jet frequency. Receiver-operating characteristic (ROC) plots were constructed to determine the best cut-off for RJF, in order to identify renal units with obstructive hydronephrosis.

RESULTS

Twenty-three (45.1%) hydronephrotic units were considered obstructed. The mean RJF differed between obstructive (0.09+/-0.15) and non-obstructive hydronephrosis (0.42+/-0.11) (p<0.001). ROC analysis revealed that RJF <0.25 was the best threshold, and correctly discriminated obstruction in 91.2% of the children with a sensitivity of 87% (95% CI 78.6-98.2%) and specificity of 96.4% (95% CI 87.8-99%). The positive likelihood ratio was 24.3 and the area under the ROC curve was 0.92 (95% CI 0.86-0.98).

CONCLUSIONS

RJF <25% was found to be a good indicator of obstruction in children with unilateral hydronephrosis. CDUS evaluation of ureteric jets is an easy and non-invasive method that can be used as an initial diagnostic tool, and in follow-up cases, to differentiate obstructed from non-obstructed hydronephrosis in the pediatric population.

Evaluation of ureterocele with Doppler sonography

Ureterocele is a common disorder characterized by cystic dilatation of the terminal submucosal portion of 1 or both ureters. Conventional imaging modalities for the diagnosis of ureterocele include intravenous urography and voiding cystourethrography; gray-scale sonography, augmented by color Doppler and spectral analysis studies, can be useful in diagnosing and managing this condition as well. We describe the diagnosis of ureterocele using transvaginal gray-scale and color Doppler sonography with spectral analysis in 2 women. Color Doppler sonography demonstrated urine flow into the bladder, and spectral analysis was used to measure the flow velocity. Together, these modalities can provide additional information about urinary flow dynamics, aid in implementing treatment for patients with ureterocele, and eliminate the need for invasive diagnostic procedures.

Ultrasonic diagnosis of ureteral injury after laparoscopically-assisted vaginal hysterectomy

Ureteral injuries are uncommon but serious complications of laparoscopically-assisted vaginal hysterectomy. The ureter is particularly at risk for inadvertent injury when the cardinal-uterosacral ligament complex is coagulated and divided below the uterine vessels. We present two recent cases which describe the application of transabdominal ultrasound including color Doppler mapping in the diagnosis of ureteral injury after laparoscopically-assisted vaginal hysterectomy. Transabdominal ultrasound including color Doppler mapping has great diagnostic potential as a method for non-invasive evaluation of post-operative ureteral conditions. Ultrasonic triads (absence of a ureteric jet, ascites, and the presence or absence of hydronephrosis) are capable of differentiating diagnosis of complete, partial, or nonobstructive surgical ureteral injuries.

Ultrasonographic detection of ureteral jets in normal pregnancy

OBJECTIVE

Our purpose was to determine the impact of normal physiologic urodynamic alterations of pregnancy on the detection of ureteral jets into the bladder with use of transabdominal color Doppler ultrasonography.

STUDY DESIGN

We conducted a prospective cohort study of 125 healthy asymptomatic gravid women without any history of past or current renal disease, all with singleton pregnancies between 13.4 and 37.7 weeks' gestation. Right and left ureteral jets were recorded over a 5-minute period with use of color Doppler transabdominal ultrasonography and a full bladder. Each kidney was graded by the severity of the hydronephrosis. No hydronephrosis was grade 0, mild hydronephrosis was grade 1, and moderate hydronephrosis was grade 2. There were no cases of severe hydronephrosis.

RESULTS

There were 56 grade 0 cases on the right versus 93 grade 0 cases on the left (p < 0.0001), 53 versus 30 grade 1 cases (right vs left, p < 0.003) and 16 versus 2 grade 2 cases (right vs left, p < 0.0009). In the subgroup where both kidneys were grade 0 the mean number of right ureteral jets 5 mm was 14.7 versus 15.1 for the left ureteral jets (p = 0.73). In the grade 1 subgroup mean right versus left ureteral jets was 15.4 versus 16.6 (p = 0.65). For the grade 2 subgroup mean right versus left ureteral jets was 15.5 versus 21.0 (p = 0.32). There were 4 of 125 unilateral absent ureteral jets on the right versus 0 of 125 on the left (p = 0.122).

CONCLUSION

Our data demonstrate that ureteral jets can be readily detected during pregnancy independent of the gestational age. In addition, it does not appear that the physiologic urodynamic alterations of pregnancy affect the frequency or symmetry of ureteral jets. Thus identification of ureteral jets can be used in the workup of suspected urolithiasis in pregnant patients.