MRI suggests increased tonicity of the levator ani in women with interstitial cystitis/bladder pain syndrome

Reducing pain by improving brain and muscle activity with motor cortical neuromodulation in women with interstitial cystitis/bladder pain syndrome: a study protocol for a randomized controlled trial

INTRODUCTION

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic pain condition creating a wide range of urologic and pain symptoms. There is currently limited evidence to understand the mechanisms of IC/BPS. There have been recent studies suggesting that altered function in brain motor areas, particularly the supplementary motor cortex (SMA), relates to altered bladder sensorimotor control and may play an important role in IC/BPS. This study aims to provide evidence that non-invasive stimulation targeting the motor cortex may help reduce IC/BPS pain, as well as better understand the neural mechanism by which this stimulation targets neuromuscular dysfunction. This study is a two-group quadruple-blinded randomized controlled trial (RCT) of active vs. sham repetitive transmagnetic stimulation (rTMS). In addition, our study will also include functional magnetic resonance imaging (fMRI), pelvic floor electromyography (EMG), pelvic exam, and outcome measures and questionnaires to further study outcomes.

ETHICS AND DISSEMINATION

All aspects of the study were approved by the Institutional Review Board of the University of Southern California (protocol HS-20-01021). All participants provided informed consent by the research coordinator/assistants. The results will be submitted for publication in peer-reviewed journals and disseminated at scientific conferences.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04734847. Registered on February 1, 2021.

Cytokines in Bladder Pain Syndrome: A Review of the Literature

INTRODUCTION AND HYPOTHESIS

Bladder pain syndrome (BPS) is poorly understood with both the aetiology and pathophysiology being unknown. Symptoms overlap with other disorders, such as overactive bladder (OAB) and chronic pelvic pain disorders such as endometriosis, making a consensus on how to diagnosis and manage patients challenging. The development of biomarkers for BPS may be the key to understanding more about its pathophysiology, as well as aiding diagnosis, subclassification, and discovering new drug targets for its management. As inflammation is widely understood to hold a central role in BPS, the evaluation of cytokines has gained interest. This article summarises the current literature and understanding of urinary, serum, and bladder tissue cytokines found elevated in patients with bladder pain syndrome.

METHODS

literature search using Pub Med with the keywords "bladder pain syndrome", "painful bladder syndrome", "bladder pain", "Interstitial cystitis" AND "cytokines" or "inflammation". This study was except from institutional approval.

RESULTS

Thirty-six cytokines have been identified as being statistically significantly elevated in either the serum, urine, or bladder tissue of patients with bladder pain syndrome in the 22 studies identified in this review of the literature. These cytokines include those from the interleukin group (n = 14), the CXC chemokine group (n = 5), and the C-C chemokine group (n = 7).

CONCLUSIONS

CXCL-1, CXCL-8, CXCL-9, CXCL-10, CXCL-11 from the CXC chemokine group, and CCL2, CCL4, CCL5, CCL7, and CCL11 from the C-C chemokine group have been found to be significantly elevated in patients with bladder pain in the literature. Many of these analytes also have supporting evidence for their roles in bladder pain from animal models and studies in other chronic inflammatory conditions. It is likely that a single cytokine will not serve as an adequate biomarker of disease in bladder pain syndrome for either diagnosis or disease severity. Instead, panels of inflammatory mediators may reveal more about the different pathways of inflammation leading to similar presentations of bladder pain in patients.

Chronic Pelvic Pain, Vulvar Pain Disorders, and Proteomics Profiles: New Discoveries, New Hopes

Chronic pelvic pain (CPP) is generally defined as non-cyclic pain perceived in the pelvic area that has persisted from three to six months or longer and is unrelated to pregnancy. The etiology of CPP is complex, multifactorial, with heterogeneous presentation, and includes several diseases such as endometriosis, adenomyosis, and interstitial cystitis/bladder pain syndrome. It may also be associated with sexual dysfunction, musculoskeletal disorders, and comorbid psychiatric symptoms. Vulvar pain disorders (VPDs) are typically categorized separately from chronic pelvic pain; among all VPDs, vulvodynia is a chronic vulvar pain of unknown etiology, lasting at least 3 months and that might be associated with other potentially linked factors. Proteomics represents a useful approach to study the proteome profiles of clinical samples. In this review, we have considered a selection of articles that have analyzed the protein abundance and novel protein species from various biological samples, including eutopic/ectopic endometrium, urine, serum, follicular, peritoneal fluid, and cervical mucus, potentially involved in the pathogenesis and progression of CPP and VPDs. These findings could represent valuable targets for paving the way for the differential diagnosis and therapeutic management of CPP and VDPs, thereby optimizing both the prevention and treatment of these conditions.

Objective Changes in Pelvic Floor Muscle Strength and Length in Women With High-Tone Pelvic Floor Dysfunction After Pelvic Floor Physical Therapy (RELAX Trial)

IMPORTANCE

Although pelvic floor physical therapy (PFPT) is effective in treating high-tone pelvic floor dysfunction (HTPFD), data on the mechanism of improvement are limited.

OBJECTIVES

This study aimed to compare squeeze intravaginal closure force after 6 weeks of PFPT in women affected by HTPFD and, secondarily, to describe changes in levator dimensions and short-term effects of PFPT on bladder, bowel, and pain symptoms.

METHODS

We conducted a prospective cohort study of patients undergoing 6 sessions of PFPT for the diagnosis of HTPFD. At baseline, we measured intravaginal closure force using an instrumented speculum, levator hiatal dimension using a 3-dimensional endovaginal ultrasonography, and symptom severity using 3 validated questionnaires. Intravaginal closure force and symptoms were reevaluated after the second, fourth, and sixth PFPT sessions, and levator hiatus was reevaluated at the sixth session.

RESULTS

Twenty-six women were enrolled and 22 completed 6 sessions and are included in the analysis. Contrary to our hypothesis, mean ± SD vaginal closure force (N) did not demonstrate a significant change (3.27 ± 2.34 vs 3.67 ± 2.02 N, P = 0.18). However, mean levator hiatal area (cm2) increased between visit 1 (13.71 ± 1.77 cm2) and visit 6 (14.43 ± 2.17 cm2, P = 0.05), as did the transverse diameter (3.83 ± 0.03 vs 3.95 ± 0.03 cm, P = 0.04). Survey responses demonstrated significant improvements across all measures of genitourinary symptoms, pain, lower gastrointestinal symptoms and quality-of-life measures after 6 sessions of PFPT.

CONCLUSION

Although the levator hiatal area increased after 6 sessions of PFPT (suggesting muscle lengthening), we were unable to demonstrate that this changed the force generated by pelvic floor muscles as measured by a speculum.

Is there a difference in pelvic floor muscle tone between women with and without pelvic pain? A systematic review and meta-analysis

BACKGROUND

Alterations in pelvic floor muscle (PFM) function have been observed in women with persistent noncancer pelvic pain (PNCPP) as compared with women without PNCPP; however, the literature presents conflicting findings regarding differences in PFM tone between women with and without PNCPP.

AIM

To systematically review the literature comparing PFM tone in women with and without PNCPP.

METHODS

MEDLINE, Embase, Emcare, CINAHL, PsycINFO, and Scopus were searched from inception to June 2021 for relevant studies. Studies were included that reported PFM tone data in women aged ≥18 years with and without PNCPP. The risk of bias was assessed with the National Heart, Lung, and Blood Institute Quality Assessment Tool. Standardized mean differences (SMDs) for PFM tone measures were calculated via random effects models.

OUTCOMES

Resting PFM tone parameters, including myoelectrical activity, resistance, morphometry, stiffness, flexibility, relaxation, and intravaginal pressure, measured by any clinical examination method or tool.

RESULTS

Twenty-one studies met the inclusion criteria. Seven PFM tone parameters were measured. Meta-analyses were conducted for myoelectrical activity, resistance, and anterior-posterior diameter of the levator hiatus. Myoelectrical activity and resistance were higher in women with PNCPP than in women without (SMD = 1.32 [95% CI, 0.36-2.29] and SMD = 2.05 [95% CI, 1.03-3.06], respectively). Women with PNCPP also had a smaller anterior-posterior diameter of the levator hiatus as compared with women without (SMD = -0.34 [95% CI, -0.51 to -0.16]). Meta-analyses were not performed for the remaining PFM tone parameters due to an insufficient number of studies; however, results of these studies suggested greater PFM stiffness and reduced PFM flexibility in women with PNCPP than in women without.

CLINICAL IMPLICATIONS

Available evidence suggests that women with PNCPP have increased PFM tone, which could be targeted by treatments.

STRENGTHS AND LIMITATIONS

A comprehensive search strategy was used with no restriction on language or date to review studies evaluating PFM tone parameters between women with and without PNCPP. However, meta-analyses were not undertaken for all parameters because few included studies measured the same PFM tone properties. There was variability in the methods used to assess PFM tone, all of which have some limitations.

CONCLUSION

Women with PNCPP have higher PFM tone than women without PNCPP; therefore, future research is required to understand the strength of the relationship between pelvic pain and PFM tone and to investigate the effect of treatment modalities to reduce PFM tone on pelvic pain in this population.

Broaden Horizons: The Advancement of Interstitial Cystitis/Bladder Pain Syndrome

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a debilitating disease that induces mental stress, lower urinary symptoms, and pelvic pain, therefore resulting in a decline in quality of life. The present diagnoses and treatments still lead to unsatisfactory outcomes, and novel diagnostic and therapeutic modalities are needed. Although our understanding of the etiology and pathophysiology of IC/BPS is growing, the altered permeability of the impaired urothelium, the sensitized nerves on the bladder wall, and the chronic or intermittent sensory pain with inaccurate location, as well as pathologic angiogenesis, fibrosis, and Hunner lesions, all act as barriers to better diagnoses and treatments. This study aimed to summarize the comprehensive information on IC/BPS research, thereby promoting the progress of IC/BPS in the aspects of diagnosis, treatment, and prognosis. According to diverse international guidelines, the etiology of IC/BPS is associated with multiple factors, while the presence of Hunner lesions could largely distinguish the pathology, diagnosis, and treatment of non-Hunner lesions in IC/BPS patients. On the basis of the diagnosis of exclusion, the diverse present diagnostic and therapeutic procedures are undergoing a transition from a single approach to multimodal strategies targeting different potential phenotypes recommended by different guidelines. Investigations into the mechanisms involved in urinary symptoms, pain sensation, and bladder fibrosis indicate the pathophysiology of IC/BPS for further potential strategies, both in diagnosis and treatment. An overview of IC/BPS in terms of epidemiology, etiology, pathology, diagnosis, treatment, and fundamental research is provided with the latest evidence. On the basis of shared decision-making, a multimodal strategy of diagnosis and treatment targeting potential phenotypes for individual patients with IC/BPS would be of great benefit for the entire process of management. The complexity and emerging evidence on IC/BPS elicit more relevant studies and research and could optimize the management of IC/BPS patients.

Pelvic floor dysfunctions in women with systemic lupus erythematosus: A cross-sectional study

INTRODUCTION AND HYPOTHESIS

As a result of the impairment of the musculoskeletal system, the pelvic floor muscles are likely compromised in women with systemic lupus erythematosus (SLE). We hypothesized that women with SLE would report more symptoms of pelvic floor dysfunction (PFD) and there will be an association between SLE and PFD.

METHODS

An online cross-sectional survey was conducted. Data were collected on demographic and anthropometric characteristics, PFD (urinary incontinence, nocturia, anal incontinence, genital-pelvic pain/penetration disorder and pelvic organ prolapse) and obstetric history using a web-based questionnaire. The groups were compared using the Mann-Whitney test for quantitative variables and the chi-squared test for categorical variables. The association between SLE and PFD was tested using logistic regression analysis.

RESULTS

A total of 196 women answered the questionnaire (102 with SLE and 94 healthy controls). Women with SLE reported significantly more urinary incontinence, nocturia, anal incontinence, pelvic organ prolapse and genital-pelvic pain/penetration disorder than the healthy controls (p ≤ 0.05). Women with SLE were 2.8- to 3.0-fold more likely to report genital-pelvic pain/penetration disorder than healthy women.

CONCLUSIONS

The prevalence of PFD was significantly higher in women with SLE compared to healthy women. Thus, PFD seems to be an important problem in women with this disease. An in-depth investigation of these disorders could contribute to the understanding of how SLE impacts pelvic floor function.

MRI as a Tool to Assess Interstitial Cystitis Associated Bladder and Brain Pathologies

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic, often incapacitating condition characterized by pain seeming to originate in the bladder in conjunction with lower urinary tract symptoms of frequency and urgency, and consists of a wide range of clinical phenotypes with diverse etiologies. There are currently no diagnostic tests for IC/BPS. Magnetic resonance imaging (MRI) is a relatively new tool to assess IC/BPS. There are several methodologies that can be applied to assess either bladder wall or brain-associated alterations in tissue morphology and/or pain. IC/BPS is commonly associated with bladder wall hyperpermeability (BWH), particularly in severe cases. Our group developed a contrast-enhanced magnetic resonance imaging (CE-MRI) approach to assess BWH in preclinical models for IC/BPS, as well as for a pilot study for IC/BPS patients. We have also used the CE-MRI approach to assess possible therapies to alleviate the BWH in preclinical models for IC/BPS, which will hopefully pave the way for future clinical trials. In addition, we have used molecular-targeted MRI (mt-MRI) to quantitatively assess BWH biomarkers. Biomarkers, such as claudin-2, may be important to assess and determine the severity of BWH, as well as to assess therapeutic efficacy. Others have also used other MRI approaches to assess the bladder wall structural alterations with diffusion-weighted imaging (DWI), by measuring changes in the apparent diffusion coefficient (ADC), diffusion tensor imaging (DTI), as well as using functional MRI (fMRI) to assess pain and morphological MRI or DWI to assess anatomical or structural changes in the brains of patients with IC/BPS. It would be beneficial if MRI-based diagnostic tests could be routinely used for these patients and possibly used to assess potential therapeutics.

Examination of pelvic floor muscle elasticity in patients with interstitial cystitis/bladder pain syndrome using real-time tissue elastography

INTRODUCTION AND HYPOTHESIS

The aim was to compare pelvic floor muscle (PFM) elasticity between interstitial cystitis/bladder pain syndrome (IC/BPS) patients and healthy women using real-time tissue elastography.

METHODS

The subjects were 17 IC/BPS female patients (IC/BPS group; age 34-84 years), 10 healthy middle-aged women (middle-aged group; 50-80 years), and 17 healthy young adult women (young group; 23-37 years). The target sites of elastography were the striated urethral sphincter (SUS) and adipose tissue as the reference site; muscle elasticity was calculated as the strain ratio (SR) of the SUS to the reference site. Evaluations were performed at rest and during PFM contraction. The IC/BPS group completed lower urinary tract symptom and pain questionnaires. SUS SR was compared among the three groups. SUS SR at rest and during PFM contraction was compared among the three groups with the t-test and the Wilcoxon test. Associations between questionnaire results and SUS SR were evaluated by correlation analysis.

RESULTS

There was no significant difference in age between the IC/BPS and middle-aged groups, but the young group was significantly younger than the other groups (p < 0.001). SUS SR at rest was significantly higher in the IC/BPS group than in the middle-aged (p = 0.014) and young groups (p = 0.002). Furthermore, in the IC/BPS group, there was no significant difference in SUS SR between at rest and during PFM contraction. SUS SR was not significantly correlated with questionnaire results for lower urinary tract symptoms.

CONCLUSIONS

SUS SR at rest was significantly higher in the IC/BPS group than in the young and middle-aged groups.

Phenotypes of BPS/IC

Purpose of Review

The aim of this review is to summarise the latest research related to different phenotypes of BPS/IC, addressing the evidence for current well-defined phenotypes as well as identifying novel potential phenotypes and highlighting areas for future study.

Recent Findings

Two distinct phenotypes of BPS/IC are well-recognised: Hunner’s lesion disease and non-Hunner’s lesion BPS/IC. Recent studies have shown these phenotypes exhibit distinct clinical, pathological and cystoscopic features, and targeted treatment to Hunner’s lesions can prove effective. Recent studies have also identified new potential phenotypes based on biochemical, molecular and histological markers, pathophysiological mechanisms of disease, clinical features, cystoscopic findings, radiological features and urodynamic factors. This evidence has improved our understanding of the underlying mechanism of disease and may enable more personalised and targeted therapy in the future.

Summary

Novel phenotypes of BPS/IC relate to the presence of certain biomarkers, alterations in the urinary microbiome, the characteristics of pain and presence of co-existing somatic and psychosocial conditions, altered patterns of brain white matter changes and urodynamic features. Further study is required to evaluate whether these potential phenotypes are clinically useful based on their ability to guide treatment selection and predict outcome from therapy, and therefore optimise therapeutic outcomes.

"The Overactive Pelvic Floor (OPF) and Sexual Dysfunction" Part 1: Pathophysiology of OPF and Its Impact on the Sexual Response

INTRODUCTION

Overactive pelvic floor (OPF) muscles are defined as muscles that do not relax, or may even contract, when relaxation is needed, for example, during micturition or defecation. Conditions associated with OPF are multifactorial and include multiple possible etiologies and symptom complexes. The complex interplay between biological and psychosocial elements can lead to the persistence of OPF symptoms along with psychological and emotional distress.

OBJECTIVES

(1) To review and contextualize, from a pathophysiologic perspective, the evidence for OPF, (2) to provide an overview of common clinical presentations and comorbidities of OPF, and (3) to discuss the effect of OPF on sexual function in men and women.

METHODS

Review of the updated literature on the pathophysiology of OPF was carried out. OPF-associated conditions were overviewed, with special emphasis on the impact on sexual function in men and women.

RESULTS

Individuals with suspected OPF often present with a combination of gastrointestinal, gynecological, musculoskeletal, sexual, and urological comorbidities, mostly accompanied by psychoemotional distress. In both women and men, sexual function is significantly impaired by OPF and genitopelvic pain penetration disorders are often the primary manifestation of this condition. Women with OPF report less sexual desire, arousal, and satisfaction; more difficulty reaching orgasm; lower frequencies of intercourse; more negative attitudes toward sexuality; and more sexual distress than women without sexual pain. The most frequently reported sexual dysfunctions in men with OPF include erectile dysfunction, premature ejaculation, and ejaculatory pain.

CONCLUSION

The complex pathophysiology of OPF involving multisystemic comorbidities and psychosocial factors emphasize the importance of a biopsychosocial assessment for guiding effective and personalized management. Padoa A, McLean L, Morin M, et al. "The Overactive Pelvic Floor (OPF) and Sexual Dysfunction" Part 1: Pathophysiology of OPF and Its Impact on the Sexual Response. Sex Med 2021;9:64-75.

How can we improve the diagnosis and management of bladder pain syndrome? Part 1: ICI-RS 2018

BACKGROUND

This paper summarizes the discussion in a think tank at the ICI-RS 2018 about the diagnosis of bladder pain syndrome (BPS).

AIMS

To review the guidelines, investigations and subtypes of BPS.

MATERIALS AND METHODS

Review of literature in the light of the think tank discussion.

RESULTS

All guidelines recommend completing history, physical examination, urine analysis, urine culture, and urine cytology to define the BPS phenotype but there are differences on further investigations. In those guidelines which recommend cystoscopy, the identification of Hunner's lesions (HLs) is recommended as this changes the treatment plan and outcome.

CONCLUSION

We propose that the differentiation of Hunner's ulcers is an important step in the assessment of these patients. Further suggestions for research are suggested.

Recent advances in imaging and understanding interstitial cystitis

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a debilitating condition associated with intense pelvic pain and bladder storage symptoms. Since diagnosis is difficult, prevalence estimates vary with the methodology used. There is also a lack of proven imaging tools and biomarkers to assist in differentiation of IC/BPS from other urinary disorders (overactive bladder, vulvodynia, endometriosis, and prostatitis). Current uncertainty regarding the etiology and pathology of IC/BPS ultimately impacts its timely and successful treatment, as well as hampers future drug development. This review will cover recent developments in imaging methods, such as magnetic resonance imaging, that advance the understanding of IC/BPS and guide drug development.

ACR Appropriateness Criteria® Postmenopausal Subacute or Chronic Pelvic Pain

Pelvic pain is common in both reproductive age and postmenopausal women, and the major etiologies change throughout the life cycle. Chronic pain is defined as lasting for at least 6 months. There are many gastrointestinal and urinary disorders associated with chronic pain in this age group, which are not discussed in this guideline. Pain may be localized to the deep pelvis, with potential causes including pelvic congestion syndrome, intraperitoneal adhesions, hydrosalpinx, chronic inflammatory disease, or cervical stenosis. Ultrasound is the initial imaging modality of choice, while CT and MRI may be appropriate for further characterization of sonographic findings. Alternatively, pain may be localized to the vagina, vulva, or perineum, with potential causes including vaginal atrophy, vaginismus, vaginal or vulvar cysts, vulvodynia, or pelvic myofascial pain. Imaging is primarily indicated in context of an abnormal physical exam and ultrasound is the initial modality of choice, while MRI may be appropriate for further characterization in select cases. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Technique development and measurement of cross-sectional area of the pubovisceral muscle on MRI scans of living women

INTRODUCTION AND HYPOTHESIS

Measurements of the anatomic cross-sectional area (CSA) of the pubovisceral muscle (PVM) in women are confounded by the difficulty of separating the muscle from the adjacent puborectal (PRM) and iliococcygeal (ICM) muscles when visualized in a plane orthogonal to the fiber direction. We tested the hypothesis that it might be possible to measure the PVM CSA within a defined region of interest based on magnetic resonance images (MRI).

METHODS

MRI scans of 11 women with unilateral PVM tears and seven primiparous women with intact muscles following elective C-section were used to identify the PVM injury zone defined by the mean location of its boundaries with the adjacent intact PRM and ICM from existing anatomic reference points using 3D Slicer and ImageJ software. Then, from the 15 or more 2-mm transverse slices available, the slice with the maximum anatomic CSA of the left and right PVM was found in 24 primiparous women with bilaterally intact muscles who had delivered via C-section.

RESULTS

Mean [± standard deviation (SD)] of the maximum left or right PVM cross-section areas for the 24 women, measured by two different raters, was 1.25 ± 0.29 cm² (range 0.75-1.86). The 5th, 50th, and 95th percentile values were 0.77, 1.23, and 1.80 cm², respectively. Inter- and intrarater measurement repeatability intraclass correlation coefficients exceeded 0.89 and 0.90, respectively.

CONCLUSIONS

It is possible to use MRI to identify the volume of interest with the maximum anatomic cross section of the PVM belly while minimizing the inadvertent inclusion of adjacent PRM or ICM in that measurement.

Novel contrast mixture achieves contrast resolution of human bladder wall suitable for T1 mapping: applications in interstitial cystitis and beyond

PURPOSE

Instillation of novel contrast mixture (NCM) was recently shown to improve the contrast resolution of rat bladder wall with high contrast-to-noise ratio (CNR). Here, the clinical safety and the feasibility of NCM-enhanced MRI to achieve artifact-free visualization of human bladder wall suitable for quantitative measurement of the magnetic resonance (MR) longitudinal relaxation time (T1) was assessed.

METHODS

Six female subjects [two controls and two with Hunner-type interstitial cystitis IC and two with non-Hunner-type IC] consented for MRI at 3 T before and after instillation of NCM [4 mM gadobutrol and 5 mM ferumoxytol in 50 mL of sterile water for injection]. Single breath-hold fast MR acquisition in large readout bandwidth for 5-mm-thick single slice with variable flip angle was applied to minimize the motion and chemical shift artifacts in measurements of bladder wall thickness (BWT), CNR and T1 from 20 pixels.

RESULTS

NCM instillation in subjects did not evoke pain or discomfort. Fourfold increase in bladder wall CNR (*p < 0.02) and pixel size of 0.35 mm with minimal influence of artifacts allowed accurate determination of bladder wall thinning ~ 0.46 mm from 50 mL NCM (*p < 0.05). Pre-contrast bladder wall T1 of 1544 ± 34.2 ms was shortened to 860.09 ± 13.95 ms in Hunner-type IC (*p < 0.0001) relative to only 1257.42 ± 20.59 and 1258.16 ± 6.16 ms in non-Hunner-type IC and controls, respectively.

CONCLUSION

Findings demonstrate the safety and feasibility of NCM-enhanced MRI to achieve artifact-free differential contrast and spatial resolution of human bladder wall, which is suitable for measuring BWT and pixel-wise measurement of T1 in post-contrast setting.

The efficacy of botulinum toxin A and sacral neuromodulation in the management of interstitial cystitis (IC)/bladder pain syndrome (BPS), what do we know? ICI-RS 2017 think thank, Bristol

AIMS

This manuscript aims to address the evidence availale in the literature on the efficacy of Botulinum Toxin A (BoNT-A) and sacral neuromodulation (SNM) in patients suffering from Interstitial Cystitis (IC)/BPS and propose further research to identify mechanisms of action and establish the clinical efficacy of either therapy.

METHODS

At the International Consultation on Incontinence-Research Society (ICI-RS) in 2017, a panel of Functional Urologists and Urogynaecologists participated in a Think Tank (TT) discussing the management of IC/BPS by BoNT-A and SNM, using available data from both PubMed and Medicine literature searches.

RESULTS

The role of BoNT-A and SNM in the treatment of IC/BPS are discussed and mechanisms of actions are proposed. Despite the available randomized trial data on the effect of intravesical BoNT-A treatment on symptoms of IC/BPS, a consistent conclusion of a positive effect cannot be drawn at the moment, as the published studies are small and heterogeneous in design. There is substantive evidence for the positive effects of SNM on symptoms of IC/BPS patients however, during patient selection, it is important to distinguish the degree and the location of pain in order to tailor the best therapy to the right patients.

CONCLUSIONS

Both intravesical BoNT-A treatment and SNM have been shown to have positive effects in patients with IC/BPS. However, firm conclusions cannot yet be drawn. Patient-reported outcomes and quality of life should be assessed in addition to urinary and pain symptoms. Since current treatments mainly focus on symptomatic relief, future research should also focus on clarifying the pathogenic mechanisms involved in IC/BPS.

Novel contrast mixture improves bladder wall contrast for visualizing bladder injury

Here, we tested whether combined contrast-enhanced magnetic resonance imaging (CCE-MRI), using a mixture of gadolinium- and iron oxide-based contrast agents, can segment the bladder wall from the bladder lumen. CCE-MRI relies on the differences in particle size and contrast mechanisms of two agents for improved image contrast. Under isoflurane anesthesia, T1-weighted imaging of adult female Sprague-Dawley rat bladder was performed using standard turbospin echo sequences at 7 Tesla, before and after transurethral instillation of 0.3 ml of single-contrast MRI or CCE-MRI composed of 0.4-64 mM of gadolinium chelate (Gd-DTPA/Gadavist) and 5 mM ferumoxytol. Bladder wall contrast was assessed in the control group exposed to saline and in the bladder injury group exposed to 0.5 ml of protamine sulfate (10 mg/ml) for 30 min. CCE-MRI following instillation of 0.4-4 mM Gd-DTPA and 5 mM ferumoxytol mixture achieved segmentation between the bladder lumen and bladder wall. Hyperintensity in the bladder wall combined with hypointensity in the lumen is consistent with the increased diffusion of the dissolved Gd-DTPA and simultaneous localization of the larger nanoparticles of ferumoxytol in the lumen. The normalized hyperintense signal in the bladder wall increased from 0.46 ± 0.07 in control group to 0.73 ± 0.14 in the protamine sulfate-exposed group (P < 0.0001). CCE-MRI following instillation of contrast mixture identifies bladder wall changes likely associated with bladder injury with improved image contrast.