Oxytocin-Augmented and Non-Sedating High-Intensity-Focused Ultrasound (HIFU) for Uterine Fibroids Showed Promising Outcome As Compared To HIFU Alone or Uterine Artery Embolization.

The use of a modified energy transmission protocol and oxytocin augmentation is being proposed as a high-intensity-focused ultrasound (HIFU) treatment for uterine fibroids, to aim for an effective and well-tolerable treatment to be given as an out-patient procedure without anesthesia or sedation. The objective of this study was to evaluate the safety and treatment effectiveness of this new protocol. The treatment outcomes of 9 consecutive patients (study group) were compared with those of 51 patients (control group) who had been randomized (1:1) to receive HIFU (n = 24) or uterine artery embolization ([UAE] n = 27). There was no major adverse event. At 3 mo, the median proportion of fibroid volume compared with the baseline was 51.1% in the study group, significantly smaller than that in the control groups (HIFU 76.6%, UAE 66.2%). At 6 mo, all patients in the study group became symptom free (9/9, 100%), a result significantly better than that of both control groups. The proportion of patients with good quality of life was significantly higher in the study group (5/7, 71.4%) compared with the control groups (HIFU 3/24, 12.5%; UAE 7/27, 25.9%). Within 24 mo, none of the patients in the study HIFU group required re-intervention, a result significantly better than that in the control HIFU group (15/24, 62.5%). The treatment could result in a very promising long-term imaging and clinical outcome that may be better than those of UAE; however, a randomized control trial of larger scale is required for further evaluation of this treatment.

The Risk of Upper Urinary Tract Involvement in Patients With Ketamine-Associated Uropathy.

PURPOSE: The aims of this study were to investigate the prevalence of upper tract involvement in ketamine-associated uropathy, and to determine the predictors of hydronephrosis in patients with a history of ketamine abuse. METHODS: This was a cross-sectional study of a prospective cohort of patients with ketamine-associated uropathy. Data including demographics, pattern of ketamine abuse, pelvic pain and urgency or frequency (PUF) symptom score, uroflowmetry (UFM) parameters, serum renal function, and liver function tests were collected. Upon consultation, ultrasonography was performed to assess the function of the urinary system. RESULTS: From December 2011 to October 2015, we treated 572 patients with ketamine-associated uropathy. Of these patients, 207 (36.2%) had managed to achieve abstinence at the time of their first consultation. Ninety-six patients (16.8%) in the cohort were found to have hydronephrosis on ultrasonography. Univariate analysis identified age, duration of ketamine abuse, PUF symptom score, voided volume on UFM, serum creatinine levels >100 µmol/L, and an abnormal serum liver enzyme profile as factors associated with hydronephrosis. Logistic regression revealed the following parameters to be statistically related to hydronephrosis: age (adjusted odds ratio [OR], 1.090; 95% confidence interval [CI], 1.020-1.166; P=0.012), functional bladder capacity (adjusted OR, 0.997; 95% CI, 0.995-0.999; P=0.029), serum creatinine >100 µmol/L (adjusted OR, 3.107; 95% CI, 1.238-7.794; P=0.016, and an abnormal serum liver enzyme profile (adjusted OR, 1.967; 95% CI, 1.213-3.187; P=0.006). CONCLUSIONS: Ketamine-associated uropathy can involve the upper urinary tract. Patient demographics as well as investigations of UFM, renal function tests, and liver function tests may allow us to identify at-risk patients.

Tendon vascularity in overhead athletes with subacromial pain syndrome and its correlation with the resting subacromial space.

BACKGROUND: Supraspinatus tendinopathy is one of the common causes of subacromial pain syndrome (SAPS) in overhead athletes. Changes in tendon vascularity have been reported in painful tendons; however, the prevalence and distribution have not been investigated in young overhead athletes. METHODS: We conducted a cross-sectional study of 47 overhead athletes (male, 31; female, 16) aged 18 to 36 years with SAPS for >3 months. A sonographer graded the severity of the tendinopathy and area of vascularization. Ultrasound imaging was used to measure supraspinatus tendon thickness, vascularity, and resting subacromial space. A self-written program was used to semiquantify the intensity of vascularity, expressed as the vascular index. RESULTS: The majority (87.2%) of the participants had signs of tendinopathy in the supraspinatus tendon, and 40 (85.1%) of the tendinopathic tendons had vascularity. The majority (66.0%) of the vascularized subjects presented with minimal increase in vascularity, and 19.1% had moderate to severe vascularization. Most (79.2%) of the vascularization was observed in the pericortical region. The vascular index was negatively correlated with the resting subacromial space in male athletes with a reduced subacromial space (ρ = -0.63; P = .038). CONCLUSION: Of overhead athletes with SAPS, 87.2% had supraspinatus tendinopathy with minimal to moderate vascularization, with the majority of vascularization occurring in the pericortical region. In male athletes with a reduced subacromial space, greater vascularity in the supraspinatus tendon was associated with a smaller resting subacromial space.

Is decreased diameter of renal pelvis in prone position an indicator of successful pyeloplasty?

OBJECTIVE: To evaluate patients who had undergone pyeloplasty for pelviureteric junction obstruction, by measuring the anteroposterior diameter (APD) of the renal pelvis in supine and prone positions, and determine whether a decrease in APD in prone position can exclude obstruction in dilated renal system. MATERIALS AND METHODS: From January 2012 to December 2013, patients who had undergone pyeloplasty were evaluated by ultrasound in two centers. The difference of APD of the renal pelvis in supine and prone positions was obtained. Correlation was made with the pre- and post-pyeloplasty renal function by radionuclide renogram. RESULTS: There were 42 patients (31 males, 11 females; age range 5 months to 18 years). Residual hydronephrosis was detected in 41 patients of whom 35 patients (85%) showed decrease in APD by >10% in prone position. These patients and the one without hydronephrosis showed either no deterioration or improvement in renal function. Six patients (15%) showed either no change or increase in APD in prone position. Three patients (7.5%) were confirmed to have decrease in renal function indicating obstruction. Three patients (7.5%) showed no deterioration of renal function, but sluggish drainage on radionuclide renogram. CONCLUSION: Demonstration of decreased APD of renal pelvis in prone position by ultrasound is useful to differentiate obstructed from non-obstructed dilated renal system, and it correctly identified 85% candidates with successful pyeloplasty. In patients with no decrease or increase in APD at prone position, further follow-up is recommended to rule out obstruction.

One-stop clinic for ketamine-associated uropathy: report on service delivery model, patients' characteristics and non-invasive investigations at baseline by a cross-sectional study in a prospective cohort of 318 teenagers and young adults.

OBJECTIVE: To describe a service delivery model and report the baseline characteristics of patients investigated by a non-invasive approach for ketamine-associated uropathy. PATIENTS AND METHODS: This was a cross-sectional study in a prospective cohort of patients who attended their first visit and underwent non-invasive investigations at a dedicated centre to treat ketamine-associated uropathy in Hong Kong from December 2011 to July 2013. Data on demographics, illicit ketamine use, symptoms scores and voiding function parameters at baseline were prospectively collected. Differences between active abusers and ex-abusers, and risk factors for the most symptomatic group were investigated by univariate and multivariate analysis. RESULTS: In all, 318 patients completed the non-invasive assessment at their first visit and were eligible for inclusion. In all, 174 were female and the mean (sd) age of the entire cohort was 24.4 (3.1) years. Patients had used ketamine for a mean (sd) period of 81 (36) months. The mean (sd) ketamine use per week was 18.5 (15.8) g. In all, 214 patients were active abusers while 104 were ex-abusers but had persistent lower urinary tract symptoms. The mean (sd) voided volume, bladder capacity, and bladder emptying efficiency were 111.5 (110) mL, 152.5 (126) mL and 73.3 (26.9)%, respectively. The ex-abusers had a lower symptom score (19.3 vs 24.1; P < 0.001), a larger voided volume (126 vs 85 mL; P < 0.001), and a larger bladder capacity (204.8 vs 126.7 mL; P < 0.001) compared with active abusers. Multivariate analysis found female gender was associated with a higher symptom score (odds ratio [OR] 2.39; 95% confidence interval [CI] 1.35-4.23; P = 0.003) and a smaller voided volume (OR 1.9; 95% CI 1.1-3.3; P = 0.02). Ketamine taken (g/week) was another risk factor for a higher symptom score (OR 1.03; 95% CI 1.01-1.05; P = 0.002). Status of ex-abuser was the only protective factor associated with fewer symptoms, larger voided volume and bladder capacity. CONCLUSIONS: An effective service model for recruiting patients with ketamine-associated uropathy is possible. With such a service model as a platform, further prospective studies are warranted to investigate the appropriate choice of treatment for this new clinical entity.

Quantitative elastography of liver fibrosis and spleen stiffness in chronic hepatitis B carriers: comparison of shear-wave elastography and transient elastography with liver biopsy correlation.

PURPOSE: To document utility of shear-wave (SW) elastography for assessing liver fibrosis in chronic hepatitis B and to compare its performance with that of transient elastography. MATERIALS AND METHODS: Ethics committee approved the study, and informed consent was obtained. Patients with liver biopsy correlation (n = 226) and healthy patients (n = 171) were analyzed. Results of SW elastography of liver, SW elastography of spleen, and transient elastography of liver were compared and correlated according to METAVIR scores. Areas under the receiver operating characteristic curve (AUCs), binary logistic regression, and Delong test were used. RESULTS: AUC for SW elastography of liver, transient elastography of liver, and SW elastography of spleen was, respectively, 0.86, 0.80, and 0.81 for fibrosis (≥ F1 stage); 0.88, 0.78, and 0.82 for moderate fibrosis (≥ F2 stage); 0.93, 0.83, and 0.83 for severe fibrosis (≥ F3 stage); and 0.98, 0.92, and 0.84 for cirrhosis (F4 stage). SW elastography of liver showed significantly higher accuracy than transient elastography of liver and SW elastography of spleen in all fibrosis stages (P = .01-.04). SW elastography of spleen showed similar accuracy with transient elastography of liver (P = .21-.99). Combination SW elastography of liver and SW elastography of spleen to predict fibrosis staging showed diagnostic accuracy not further improved compared with SW elastography of liver alone (similar AUC; ≥ F1, P = .87; ≥ F2, P = .81; ≥ F3, P = .84; ≥ F4, P = .88). SW elastography of liver had higher successful rate than transient elastography of liver (98.9% vs 89.6%). Prevalence of discordance in at least two stages with liver histologic staging was 10.2% (23 of 226) for SW elastography of liver and 28.2% (58 of 206) for SW elastography of spleen. CONCLUSION: SW elastography provides more accurate correlation of liver elasticity with liver fibrosis stage compared with transient elastography, especially in identification of stage F2 or greater.

Quantitative estimation of muscle shear elastic modulus of the upper trapezius with supersonic shear imaging during arm positioning.

Pain and tenderness of the upper trapezius are the major complaints among people with chronic neck and shoulder disorders. Hyper-activation and increased muscle tension of the upper trapezius during arm elevation will cause imbalance of the scapular muscle force and contribute to neck and shoulder disorders. Assessing the elasticity of the upper trapezius in different arm positions is therefore important for identifying people at risk so as to give preventive programmes or for monitoring the effectiveness of the intervention programmes for these disorders. This study aimed to establish the reliability of supersonic shear imaging (SSI) in quantifying upper trapezius elasticity/shear elastic modulus and its ability to measure the modulation of muscle elasticity during arm elevation. Twenty-eight healthy adults (15 males, 13 females; mean age = 29.6 years) were recruited to participate in the study. In each participant, the shear elastic modulus of the upper trapezius while the arm was at rest and at 30° abduction was measured by two operators and twice by operator 1 with a time interval between the measurements. The results showed excellent within- and between-session intra-operator (ICC = 0.87-0.97) and inter-observer (ICC = 0.78-0.83) reliability for the upper trapezius elasticity with the arm at rest and at 30° abduction. An increase of 55.23% of shear elastic modulus from resting to 30° abduction was observed. Our findings demonstrate the possibilities for using SSI to quantify muscle elasticity and its potential role in delineating the modulation of upper trapezius elasticity, which is essential for future studies to compare the differences in shear elastic modulus between normal elasticity and that of individuals with neck and shoulder disorders.

Elastic modulus of muscle and tendon with shear wave ultrasound elastography: variations with different technical settings.

Standardization on Shear wave ultrasound elastography (SWUE) technical settings will not only ensure that the results are accurate, but also detect any differences over time that may be attributed to true physiological changes. The present study evaluated the variations of elastic modulus of muscle and tendon using SWUE when different technical aspects were altered. The results of this study indicated that variations of elastic modulus of muscle and tendon were found when different transducer's pressure and region of interest (ROI)'s size were applied. No significant differences in elastic modulus of the rectus femoris muscle and patellar tendon were found with different acquisition times of the SWUE sonogram. The SWUE on the muscle and tendon should be performed with the lightest transducer's pressure, a shorter acquisition time for the SWUE sonogram, while measuring the mean elastic modulus regardless the ROI's size.

Improvement in T-staging of rectal carcinoma: using a novel endorectal ultrasonography technique with sterile coupling gel filling the rectum.

Our purpose was to study the accuracy of using endorectal ultrasonography (ERUS) with sterile coupling gels filling the rectum in the preoperative T-staging of rectal carcinoma. A total of 189 patients with confirmed rectal carcinoma were recruited. All underwent ERUS and surgery within the week following sonography. EURS was performed by introducing sterile coupling gel into the rectum. Two radiologists looked at the images at the same time and agreed upon staging. Rectal carcinoma was staged from Tis to T4. The accuracy of T-staging by ERUS was 89.95%. The sensitivity, specificity, PPV and NPV for ERUS at different stages were calculated. For early stage (Tis and T1), these values were 93.62%, 97.89%, 93.62% and 97.89%, respectively. ERUS filling with sterile coupling gel in the rectum overcomes the pressure effect from a water bath and the restriction caused by tumor stenosis, thus, greatly improving the accuracy of T-staging. The examination is real-time, safe and inexpensive.

Ultrasound measurements on acromio-humeral distance and supraspinatus tendon thickness: test-retest reliability and correlations with shoulder rotational strengths.

OBJECTIVES: To establish the test-retest reliability of ultrasound measurements on acromio-humeral distance (AHD) and supraspinatus tendon thickness; and to explore their relationships with shoulder rotational strengths. DESIGN: Test-retest observational study. METHODS: Thirty-seven individuals (age: 21.5±1.4 years) participated in this study. Twenty-four were University volleyball players with 15 healthy and 9 players with shoulder impingement syndrome (SIS). Thirteen participants were healthy untrained individuals. Ultrasound measurements of AHD and supraspinatus tendon thickness were taken, and isokinetic testing of concentric shoulder internal rotation (IR) and external rotation (ER) at a speed of 90°/s was performed. RESULTS: The measurement of the AHD and the supraspinatus tendon thickness indicated excellent reliability (ICC=0.922, and ICC=0.933 respectively), and the minimum detectable difference (MDD) were 2.10mm and 0.64 mm respectively. A cut-off AHD distance of 23.9 mm had a sensitivity of 0.67 and specificity of 0.71 (area under curve (AUC): 0.70; p=0.05) in identifying individuals with and without SIS. Hence, individuals with AHD larger than 23.9 mm had greater possibility of having SIS. Positive correlations were found in AHD with supraspinatus tendon thickness (r=0.36, p<0.05) and shoulder external rotational strengths (r=0.47-0.62, all p<0.05) and ER/IR ratios (r=0.56-0.58, all p<0.05). CONCLUSIONS: Ultrasound measurements of AHD and tendon thickness have excellent reliability. The reported cut-off AHD highlighted the potential role of ultrasound measurements in volleyball players for early identification of SIS. The AHD was related to the supraspinatus tendon thickness and shoulder external rotation strengths. Our findings provide a scientific basis for muscle training in overhead athletes such as volleyball players.

Dynamic ultrasound study on urinary bladder in infants with antenatally detected fetal hydronephrosis.

UNLABELLED: To evaluate bladder function in infants with antenatally diagnosed hydronephrosis (ANH) using dynamic ultrasound protocol. Forty consecutive male infants (mean, 0.25 y) with ANH and 33 age-matched normal controls (mean, 0.49 y) were recruited. Anteroposterior (AP) diameter of renal pelvis (RP) and hydronephrosis index [HI = anteroposterior diameter of RP of kidney divided by urinary bladder volume (BV)] were calculated. Maximum BV (MaxBV) was determined just before voiding. Residual volume (RV) and bladder wall thickness (BWT) were measured after spontaneous voiding. Thirty-one infants (77.5%) showed persistently dilated RP postnatally in which 12 (39%) showed significantly high HI. In general, ANH infants had smaller MaxBV (30.71 versus 52.45 mL), larger residual volume (2.47 versus 1.93 mL), and larger BWT (4.4 versus 3.7 mm) than normal (p < 0.05, Mann-Whitney test). Infants with abnormally high HI had significantly more disturbed bladder parameters [smaller MaxBV (23.33 versus 33.49 mL) and larger BWT (4.67 versus 3.79 mm)] than the normal HI group (p < 0.05, Mann-Whitney test). Abnormal functional bladder parameters were evident in ANH infants. We postulated that immature function in the pelviureteric junction was associated with bladder dysfunction in these infants. Dynamic ultrasound protocol might help to understand the underlying pathophysiology of urinary system in ANH infants. ABBREVIATIONS: :

Hydronephrosis index: a better physiological reference in antenatal ultrasound for assessment of fetal hydronephrosis.

OBJECTIVE: To establish a nomogram of fetal hydronephrosis index (HI) (anteroposterior diameter of renal pelvis divided by urinary bladder volume) at different gestational ages, to serve as a new reference for antenatal ultrasound examination, and to avoid overestimation of fetal hydronephrosis due to transient effect of a distended fetal bladder. STUDY DESIGN: 504 uncomplicated singleton pregnancies from 20 to 38 weeks' gestation were included. In each fetus, the maximum anteroposterior diameters of both renal pelves were measured on transverse view of fetal kidneys. Urinary bladder volume was calculated using the ovoid volume formula. HI was derived accordingly. RESULTS: Values of HI vary significantly at different trimesters of pregnancy. HI was much higher (mean = 0.1543) from 20 to 27 weeks' gestation, and its value decreased significantly (mean = 0.0253) from 28 to 38 weeks' gestation (P < .05, independent-sample t test). As gestational age increased, HI decreased (R(2) = 0.5921). CONCLUSIONS: HI is easy to be measured and can be used as a new physiological reference for assessment of fetal hydronephrosis by eliminating the confounding effect of a full fetal bladder. The change in values of HI throughout gestation supports the clinical importance of a nomogram for this new index.

Characteristics of the bladder in infants with urinary tract infections: an ultrasound study.

BACKGROUND: Patients with urinary tract infection (UTI) are known to have impaired bladder function as demonstrated by urodynamic (UD) studies. UD is rarely performed in infants. OBJECTIVE: To evaluate bladder function in infants with UTI using a dynamic US protocol. Maximal bladder volume (MaxBV), residual volume (RV) and bladder wall thickness (BWT) were measured and compared with values from normal controls. MATERIALS AND METHODS: A total of 57 consecutive infants (47 males, 10 females; mean age 0.48+/-0.30 years) with proven UTI, and 63 age-matched normal controls (37 males, 26 females; mean age 0.47+/-0.37 years) were recruited. MaxBV was determined just before voiding, and RV and BWT were measured after spontaneous voiding. RESULTS: Infants with UTI had smaller MaxBV (34.89 vs. 42.91 ml), larger RV (3.46 vs. 1.51 ml) and greater BWT (4.21 vs. 3.68 mm) than normal infants (P<0.05, Mann-Whitney test). CONCLUSION: Smaller bladder volume, larger residual volume and thicker bladder wall in infants with UTI can be explained by bladder instability, hypercontractility and infection-induced oedema of the bladder wall during UTI. The US measurement of bladder parameters might serve as an objective guide for clinical diagnosis and allow objective evaluation of bladder function during posttreatment follow-up.

Doppler waveforms of the ureteric jet: an overview and implications for the presence of a functional sphincter at the vesicoureteric junction.

This paper is a comprehensive review of the Doppler waveform appearance of ureteric jets. Six jet waveform patterns have been identified: monophasic, biphasic, triphasic, polyphasic, square and continuous. Details of the physical properties of jet patterns and their changes under various physiological conditions are illustrated. The immature monophasic ureteric jet pattern is common in infancy and early childhood up to around 4 years of age. This pattern is also noted to have a high incidence in older children with urinary tract infection/vesicoureteric reflux, nocturnal enuresis and in other special physiological conditions such as in children undergoing general anaesthesia, in women during pregnancy, and in patients who have had ureteric transplantation. A hypothesis of dual myogenic and neurogenic components is proposed to explain the mode of action of the vesicoureteric junction (VUJ). The implication of this hypothesis is that it alters the scientific basis of the understanding of the VUJ. Furthermore, the application of colour Doppler US to ureteric jets may provide a non-invasive technique to study the physiology or pathophysiology of the VUJ in humans. This might shed light on new novel approaches to the monitoring and treatment of diseases related to VUJ function.

Nomograms of total renal volume, urinary bladder volume and bladder wall thickness index in 3,376 children with a normal urinary tract.

BACKGROUND: We have previously shown that urinary bladder volume index (BVI = length x width x depth of bladder) and bladder volume wall thickness index (BVWI = BVI at full bladder/average bladder wall thickness) are useful indicators of bladder dysfunction in children with enuresis and urinary tract infection. These indices show a good correlation with urodynamic studies. We have expanded the study to include normal paediatric subjects with a wide age range. We illustrate a simple sonography protocol with nomograms of different parameters, which provide useful references for functional assessment in children with urological abnormalities. OBJECTIVE: To construct nomograms of total renal volume, maximum BVI and BVWI based on a Chinese paediatric population with age range from newborn to adolescence. MATERIALS AND METHODS: Sonography was performed in consecutive children with normal urinary tracts on imaging, using a standardized protocol. Data were collected for construction of nomograms for different parameters. RESULTS: Nomograms of total renal volume, BVI and BVWI were constructed based on 3,376 consecutive paediatric subjects. All parameters consistently increased with age. CONCLUSION: Nomograms of total renal volume, BVI and BVWI could provide useful references for studying bladder dysfunction in children using noninvasive dynamic sonography.

Gender difference in achieving rate of maturity of the vesicoureteric junction.

BACKGROUND: Our previous study on the Doppler waveform of the urinary jet at the vesicoureteric junction (VUJ) indicates that there is an active sphincteric mechanism in humans. We have also shown that there are immature and mature patterns of the jet, and the VUJ matures around the age of 4 years. OBJECTIVE: To determine if there is any gender difference in the time of achieving maturity of the VUJ. MATERIALS AND METHODS: The Doppler pattern of the jets from both ureters was recorded in 273 normal boys and 248 normal girls. The subjects were considered to have immaturity of the VUJ if an immature jet waveform was detected in either ureter. RESULTS: The mean age of VUJ maturity was 4.54 years for the whole population, 4.88 years for boys and 4.34 years for girls. The difference between ROC curves for boys and girls was not significant (P > 0.05, simple Z test). CONCLUSION: There is no significant gender difference in the maturation of the VUJ. Detection of a persistent immature jet pattern beyond the age of maturity might have prognostic implications if there is a concurrent pathological condition related to the urinary tract in children.

Ureteric jet Doppler waveform and bladder wall thickness in children with nocturnal enuresis.

To test the hypothesis that the presence of nocturnal enuresis is related to increased frequency of immature vesicoureteric function, which is further associated with detrusor overactivity, we compared the incidence of immature monophasic ureteric jet in children with and without nocturnal enuresis. The relationship between monophasic ureteric jet Doppler wave form and bladder wall thickness was further explored in the enuresis group. Ultrasound examinations were performed in 511 children suffering from nocturnal enuresis and 266 normal controls. Doppler wave forms of the ureteric jet on each side and the bladder wall thickness after voiding were recorded. Standard urodynamic studies were obtained in 203 enuretic children for correlations with ultrasound findings. There was a significant increase in the incidence of monophasic ureteric jet waveforms in enuretic children when compared with the controls (19.2% versus 6.4% on the right side, 19.2% versus 8.3% on the left side, all p < 0.01). Furthermore, immature monophasic waveforms were more commonly seen in the enuretic group with markedly thickened bladder wall. Enuretic children with bilateral immature ureteric jet waveforms and markedly thickened bladder wall showed multiple significant urodynamic abnormalities (p < 0.05). The above observations could be accounted for by immaturity of both vesicoureteric junction and detrusor muscle.

Ureteric jet in the anaesthetised child.

We have already suggested that there is an active bimodal sphincteric mechanism in the human vesicoureteral junction (VUJ). This mechanism is affected by immaturity, hormonal effects and surgical ablation. This study set out to investigate the effects of anaesthesia on this mechanism. A total of 16 children undergoing surgery were recruited. They were well hydrated. The ureteric jets before and after anaesthesia were recorded using the colour and pulse wave Doppler. Of the total, 14 children showed mature (complex pattern) and two showed immature (monophasic pattern) waveforms before surgery. After anaesthesia, all showed the monophasic waveform (p=0.01). Thus, the sphincteric action of VUJ as manifest by the complexity of the ureteric jet was modified by anaesthesia by loss of the complex pattern. This supports the hypothesis that the complex pattern is a neural modulation of the simpler myogenic mechanism that produces the monophasic jet.

The ureteric jet doppler waveform as an indicator of vesicoureteric sphincter function in adults and children. An observational study.

The nature of the action of the vesicoureteric junction (VUJ) in humans is still controversial. We were interested in the reasons why the jet consists of several peaks. We hypothesised that the modification of the jet into a variable number of peaks is the result of an active sphincter mechanism at the VUJ. A total of 1,010 subjects of all ages and both genders were recruited into this study. The Doppler waveform of the jet was recorded bilaterally. We could identify six basic patterns of ureteric jet according to the number of peaks: monophasic, biphasic, triphasic, polyphasic (four or more peaks), square and continuous. By analysing the duration, maximum peak velocity and initial slope of the first four patterns, a mechanism of action of an active VUJ sphincter could be postulated. Furthermore, the basic patterns could be assigned to three modes of ureteric actions: the square and continuous are only seen during diuretic stress; the biphasic, triphasic and polyphasic patterns are variations of the adult physiological steady-state mode, and the monophasic is distinctly different and represents the immature mode.

Immature ureteric jet doppler patterns and urinary tract infection and vesicoureteric reflux in children.

The Doppler waveform of the ureteric jet is the result of modification of ureteric peristalsis by an active sphincteric mechanism of the vesicoureteric junction (VUJ). The monophasic pattern is associated with immaturity. This study set out to see the correlation between this immature pattern with urinary tract infection (UTI) and vesicoureteric reflux (VUR) in children. Ureteric jets of 241 healthy children and 98 children with UTI were studied. The monophasic pattern was found in 29% of healthy children overall, but varied greatly according to age. The monophasic pattern was virtually universal in the first 6 months of life, dropping to below 15% in late childhood. This immature pattern was more commonly seen in the UTI (73.5%) and VUR (90.5%) groups than in the healthy controls. The difference was statistically significant (p = 0.0005 for both). The persistence of this immature pattern was highly associated with UTI and VUR.