Transrectal ultrasound vector projectile imaging for time-resolved visualization of flow dynamics in the male urethra: A clinical pilot study.

BACKGROUND: Quantitative and comprehensive visualization of urinary flow dynamics in the urethra is crucial for investigating patient-specific mechanisms of lower urinary tract symptoms (LUTS). Although some methods can evaluate the global properties of the urethra, it is critical to assess the local information, such as the location of the responsible lesion and its interactions with urinary flow in relation to LUTS. This approach is vital for enhancing personalized and focal treatments. However, there is a lack of such diagnostic tools that can directly observe how the urethral shape and motion impact urinary flow in the urethra. PURPOSE: This study aimed to develop a novel transrectal ultrasound imaging modality based on the contrast-enhanced urodynamic vector projectile imaging (CE-UroVPI) framework and validate its clinical applicability for visualizing time-resolved flow dynamics in the urethra. METHODS: A new CE-UroVPI system was developed using a research-purpose ultrasound platform and a custom transrectal linear probe, and an imaging protocol for acquiring urodynamic echo data in male patients was designed. Thirty-four male patients with LUTS participated in this study. CE-UroVPI was performed to acquire ultrasound echo signals from the participant's urethra and urinary flow at various voiding phases (initiation, maintenance, and terminal). The ultrasound datasets were processed with custom software to visualize urinary flow dynamics and urethra tissue deformation. RESULTS: The transrectal CE-UroVPI system successfully visualized the time-resolved multidirectional urinary flow dynamics in the prostatic urethra during the initiation, maintenance, and terminal phases of voiding in 17 patients at a frame rate of 1250 fps. The maximum flow speed measured in this study was 2.5 m/s. In addition, when the urethra had an obstruction or an irregular partial deformation, the devised imaging modality visualized complex flow patterns, such as vortices and flow jets around the lesion. CONCLUSIONS: Our study findings demonstrate that the transrectal CE-UroVPI system developed in this study can effectively image fluid-structural interactions in the urethra. This new diagnostic technology has the potential to facilitate quantitative and precise assessments of urethral voiding functions and aid in the improvement of focal and effective treatments for patients with LUTS.

The Efficacy of Compression Stockings on Patients With Nocturia: A Single-Arm Pilot Study.

OBJECTIVES:  Behavioral treatment for nocturia includes wearing compression stockings. However, a reading of the cited literature for evidence shows that there is not enough research data to support this recommendation, and it is controversial. The present study aimed to investigate and supplement evidence on the effects of wearing compression stockings during the daytime in patients with nocturia. METHODS: This was a single-arm prospective study to investigate the effects of compression stockings on nocturia for four weeks. Patients were asked to record a frequency-volume chart and complete various questionnaires at baseline and after four weeks, and also provide feedback on treatment satisfaction. The primary endpoint was a change in night-time frequency in the frequency-volume chart from the baseline to the end of treatment. RESULTS: Thirty-four patients (19 men and 15 women; age: 72.3 ± 12.6 years) were included. Two patients dropped out because of pain associated with wearing compression stockings and one due to a refusal to wear compression stockings every day. Therefore 31 patients were analyzed. In the frequency-volume chart, night-time and 24-hour frequencies significantly decreased by 0.5 and 1.1 episodes, respectively (P = 0.004 and P = 0.035, respectively). The hours of undisturbed sleep significantly increased by 0.8 h (P = 0.013). No significant differences were observed in nocturnal or 24-h urine volumes, the number of urgency or urinary incontinence episodes, the mean or maximum voided volume, the nocturnal polyuria index, or the first night-time voided volume. The total overactive bladder symptom score significantly decreased (P = 0.006). Significant reductions were also observed in all overactive bladder symptom score subscores, except for the daytime frequency score. CONCLUSION: The present results suggest the effectiveness of wearing compression stockings during the day was satisfactory in most patients with nocturia, and the treatment was safely continued in patients who experienced no pain when wearing the stockings. Based on the results of this study, we believe that it is worth considering as a treatment for nocturia.

Possible bidirectional human-swine and subsequent human-human transmission of influenza virus A(H1N1)/2009 in Japan.

In 2019, sows at a swine farm in Japan showed influenza-like illness (ILI) shortly after contact with an employee that exhibited ILI. Subsequently, a veterinarian became sick shortly after examining the sows and was diagnosed with influenza A virus (IAV) infection. Then, her family also contracted the infection. Subsequently, Pandemic A(H1N1)2009 viruses were isolated from all samples obtained from the sows, veterinarian and her family. Whole-genome analysis of the isolates confirmed that the viruses belonged to the same lineage (6B.1A) and the genome sequences obtained from all of the isolates were almost identical to each other. Furthermore, an epidemiological survey revealed no contact between veterinarians or their families and influenza patients prior to the onset of illness. These results strongly indicated a case of bidirectional infection between humans and sows. At the same time, we found a few unique mutations in the IAV genomes corresponding to the host species. The mutations that occurred in the virus after it was transferred from the farm worker to the sows were not observed in the humans infected from the sows, probably as a result of the mutations reverting to the original nucleotides. These results demonstrate that the bidirectional transmission of IAV is a potential risk for the next pandemic outbreak due to the emergence of new mutant strains.

Lower Urinary Tract Function in Familial Spastic Paraplegia.

In order to investigate lower urinary tract function in hereditary spastic paraplegia (HSP), we recruited 12 HSP patients: 8 men, 4 women; mean age, 64.6 years; mean disease duration, 18.9 years; walk without cane, 2, walk with cane, 6, wheelchair bound, 3. We performed urinary symptom questionnaires and a urodynamic testing in all patients. As a result, urinary symptoms were observed in all but 3, including urinary urgency/frequency (also called overactive bladder) in 9 and hesitancy/poor stream in 6. Urodynamic abnormalities included detrusor overactivity during bladder filling in 10, underactive detrusor on voiding in 8 (detrusor hyperactivity with impaired contraction [DHIC] in 5), detrusor-sphincter dyssynergia (DSD) on voiding in 3, and post-void residual in 5. Sphincter electromyography showed neurogenic motor unit potential in 4. In conclusion, we observed high frequency of urinary symptoms in HSP. Urodynamics indicated that the main mechanism is DHIC with/without DSD for their urinary symptom, and sacral cord involvement in some cases. These findings facilitate patients' care including clean, intermittent catheterization.

Neuromodulation for the Treatment of Lower Urinary Tract Symptoms.

Neuromodulation therapy incorporates electrical stimulation to target specific nerves that control lower urinary tract symptoms (LUTS). The objectives of this article are to review the mechanism of action, the type of neuromodulation, and the efficacy of neuromodulation mainly according to the results of randomized controlled trials. Neuromodulation includes pelvic floor electrical stimulation (ES) using vaginal, anal and surface electrodes, interferential therapy (IF), magnetic stimulation (MS), percutaneous tibial nerve stimulation, and sacral nerve stimulation (SNS). The former four stimulations are used for external periodic (short-term) stimulation, and SNS are used for internal, chronic (long-term) stimulation. All of these therapies have been reported to be effective for overactive bladder or urgency urinary incontinence. Pelvic floor ES, IF, and MS have also been reported to be effective for stress urinary incontinence. The mechanism of neuromodulation for overactive bladder has been reported to be the reflex inhibition of detrusor contraction by the activation of afferent fibers by three actions, i.e., the activation of hypogastric nerve, the direct inhibition of the pelvic nerve within the sacral cord and the supraspinal inhibition of the detrusor reflex. The mechanism of neuromodulation for stress incontinence is contraction of the pelvic floor muscles through an effect on the muscle fibers as well as through the stimulation of pudendal nerves. Overall, cure and improvement rates of these therapies for urinary incontinence are 30-50, and 60-90% respectively. MS has been considered to be a technique for stimulating nervous system noninvasively. SNS is indicated for patients with refractory overactive bladder and urinary retention.

Six-year follow up of silodosin monotherapy for the treatment of lower urinary tract symptoms suggestive of benign prostatic hyperplasia: What are the factors for continuation or withdrawal?

OBJECTIVES: To investigate the factors for continuation or withdrawal as an extension of a prospective study of silodosin monotherapy for the treatment of lower urinary tract symptoms suggestive of benign prostatic hyperplasia for more than 6 years. METHODS: A total of 104 patients (age 71.5 ± 8.2 years) were enrolled in the present study. The mean prostate volume was 44.1 ± 23.9 mL. International Prostate Symptom Score, quality of life index, maximum flow rate, and postvoid residual urine volume were determined at baseline, and at 1, 3, 6 and 12-72 months after treatment. RESULTS: Adverse events were noted in 14 patients (13.5%), and the most frequent adverse event was ejaculatory dysfunction (5.8%). Withdrawal was noted in 78 patients, and 26 patients (25.0%) were still taking silodosin at 72 months (continuing group). The reasons for withdrawals were: unknown in 27 patients (26.0%), adverse events in nine patients (8.7%), unsatisfactory effects in 30 patients (28.8%) and satisfied with the current condition for six patients (5.8%). In 30 patients who withdrew because of unsatisfactory effects, surgery was carried out in 21 patients (surgery group). The baseline total International Prostate Symptom Score did not differ between the continuing group and the surgery group. However, patients with the continuing group had significantly smaller baseline prostate volume, and lower baseline quality of life index and prostate-specific antigen, than in the surgery group. The mean total International Prostate Symptom Score, quality of life index and maximum flow rate improved significantly at 1 month, and remained stable up to 72 months. CONCLUSIONS: The withdrawal rate was higher in patients with a larger prostate. The effects of silodosin for lower urinary tract symptoms was immediate and stable up to 72 months.

The role of muscarinic receptor subtypes on carbachol-induced contraction of normal human detrusor and overactive detrusor associated with benign prostatic hyperplasia.

The aim of this study was to compare the effect of antimuscarinic antagonists on carbachol-induced contraction of normal human bladder and detrusor overactivity associated with benign prostatic hyperplasia (DO/BPH). Samples of human bladder muscle were obtained from patients undergoing total cystectomy for bladder cancer (normal bladder), and those undergoing retropubic prostatectomy for BPH. All of the patients with DO/BPH had detrusor overactivity according to urodynamic studies. Detrusor muscle strips were mounted in 10-ml organ baths containing Krebs solution, and concentration-response curves for carbachol were obtained in the presence of antimuscarinic antagonists (4-DAMP, methoctramine, pirenzepine, tolterodine, solifenacin, trospium, propiverine, oxybutynin, and imidafenacin) or vehicle. All antagonists competitively antagonized concentration-response curves to carbachol with high affinities in normal bladder. The rank order of mean pA2 values was as follows: trospium (10.1) > 4-DAMP (9.87), imidafenacin (9.3) > solifenacin (8.8) > tolterodine (8.6) > oxybutynin (8.3) > propiverine (7.7) > pirenzepine (7.4) > methoctramine (6.6). The effects of these antimuscarinic antagonists did not change when tested with DO/BPH bladder, suggesting that each antimuscarinic antagonist has a similar effect in this condition. Schild plots showed a slope corresponding to unity, except for propiverine with DO/BPH detrusor. In conclusion, M3-receptors mainly mediate contractions in human bladder strips with normal state and DO/BPH.

Tolterodine activates the prefrontal cortex during bladder filling in OAB patients: a real-time NIRS-urodynamics study.

AIMS: Studies of overactive bladder (OAB) have shown urothelial/suburothelial changes and increased bladder afferents, while in the brain the frontal micturition area that normally suppresses the bladder is deactivated. It has been unclear whether anticholinergic medication could reverse this suppression. To address this question, we performed a real-time NIRS (near-infrared spectroscopy)-urodynamic study in OAB patients before and after the administration of an anticholinergic agent, tolterodine. METHODS: We recruited 13 OAB patients in our outpatient clinic (9 males, 4 female; mean age 73 years). Before and after the administration of 4 mg/day tolterodine for 3 months, all patients completed the OAB-symptom scale and a NIRS-urodynamics examination. Cerebral changes in the oxy-hemoglobin concentration (oxy-Hb) were sampled. Concentration changes in oxy-Hb were calculated based on a modified Beer-Lambert approach. RESULTS: Tolterodine significantly reduced the OAB patients' nighttime frequency (P < 0.05) and increased their first-sensation volume (290-359 ml, P < 0.01). The number of patients with detrusor overactivity did not lessen significantly (11-9). The real-time NIRS-urodynamic study showed that, during slow bladder filling between start and bladder capacity, tolterodine significantly activated the right frontal micturition area of the OAB patients (P < 0.05). The activation was prominent in Brodmann's area 8, 9, 10 of the prefrontal cortex. CONCLUSIONS: Tolterodine reduced bladder sensation together with a significant activation of the frontal micturition area of OAB patients, particularly Brodmann's area 8, 9, 10 of the right prefrontal cortex. This activation seems to be a secondary phenomenon, since tolterodine does not easily penetrate the blood-brain barrier.