Weight Loss Surgery Increases Kidney Transplant Rates in Patients With Renal Failure and Obesity.

OBJECTIVE: To describe the outcomes of kidney transplant (KT) candidates with obesity undergoing sleeve gastrectomy (SG) to meet the criteria for KT. METHODS: Retrospective analysis was conducted of electronic medical records of KT candidates with obesity (body mass index >35 kg/m2) who underwent SG in our institution. Weight loss, adverse health events, and the listing and transplant rates were abstracted and compared with the nonsurgical cohort. RESULTS: The SG was performed in 54 patients; 50 patients did not have surgery. Baseline demographic characteristics were comparable at the time of evaluation. Mean body mass index ± SD of the SG group was 41.7±3.6 kg/m2 at baseline (vs 41.5±4.3 kg/m2 for nonsurgical controls); at 2 and 12 months after SG, it was 36.4±4.1 kg/m2 and 32.6±4.0 kg/m2 (P<.01 for both). In the median follow-up time of 15.5 months (interquartile range, 6.4 to 23.9 months), SG was followed by active listing (37/54 people), and 20 of 54 received KT during a median follow-up time of 20.9 months (interquartile range, 14.7 to 28.3 months) after SG. In contrast, 14 of 50 patients in the nonsurgical cohort were listed, and 5 received a KT (P<.01). Three patients (5.6%) experienced surgical complications. There was no difference in overall hospitalization rates and adverse health outcomes, but the SG cohort experienced a higher risk of clinically significant functional decline. CONCLUSION: In KT candidates with obesity, SG appears to be effective, with 37% of patients undergoing KT during the next 18 months (P<.01). Further research is needed to confirm and to improve the safety and efficacy of SG for patients with obesity seeking a KT.

Management of Patients With Kidney Disease Undergoing Bariatric Surgery: A Multidisciplinary Approach.

Bariatric surgery is increasingly recognized as a safe and effective treatment for obesity in patients with chronic kidney disease (CKD), including stages 4, 5, and 5D (on dialysis). Among the available surgical methods, sleeve gastrectomy (SG) is the most commonly performed weight loss procedure and is mainly done to facilitate kidney transplantation (KT). However, many KT candidates treated with SG remain on the transplant waiting list for months to years, with some never receiving a transplant. Therefore, appropriate candidates for SG must be selected, and post-SG management should address the unique needs of this population, with a focus on sustaining the metabolic benefits of surgery while minimizing potential side effects related to rapid weight loss which may inadvertently lead to muscle and bone catabolism. Multidisciplinary post-SG care in this population may lead to overall better health on the transplant waiting list, resulting in a higher percentage of post-SG patients ultimately receiving KT. To tailor the effective treatment for these patients, clinicians should acknowledge that patients with CKD stage 4-5D have different nutritional needs and are metabolically and psychosocially distinct from the general bariatric surgery population. Sarcopenia is highly prevalent and may be exacerbated by muscle catabolism following SG if not adequately addressed. Blood pressure, glucose, and bone metabolism are all affected by the CKD stage 4-5D, and therefore require distinct diagnostic and management approaches. Long-standing chronic disease, associated comorbidities, and low adherence to medical therapies require ongoing comprehensive psychosocial assessment and support. This paper aims to review and consolidate the existing literature concerning the intersection of CKD stage 4-5D and the consequences of SG. We also suggest future clinical outcome studies examining novel treatment approaches for this medically complex population.

Mapping dysfunctional circuits in the frontal cortex using deep brain stimulation.

Frontal circuits play a critical role in motor, cognitive and affective processing, and their dysfunction may result in a variety of brain disorders. However, exactly which frontal domains mediate which (dys)functions remains largely elusive. We studied 534 deep brain stimulation electrodes implanted to treat four different brain disorders. By analyzing which connections were modulated for optimal therapeutic response across these disorders, we segregated the frontal cortex into circuits that had become dysfunctional in each of them. Dysfunctional circuits were topographically arranged from occipital to frontal, ranging from interconnections with sensorimotor cortices in dystonia, the primary motor cortex in Tourette's syndrome, the supplementary motor area in Parkinson's disease, to ventromedial prefrontal and anterior cingulate cortices in obsessive-compulsive disorder. Our findings highlight the integration of deep brain stimulation with brain connectomics as a powerful tool to explore couplings between brain structure and functional impairments in the human brain.

Pyelovesicostomy as an Alternative Surgical Treatment for Complex Ureteral Lesions After Kidney Transplant.

OBJECTIVES: We evaluated the feasibility, safety, and long-term outcomes of pyelovesicostomy as an alternative surgical treatment for complex ureteral lesions after kidney transplant. MATERIALS AND METHODS: A single-center, retrospective, observational cohort study was conducted on 5 adult kidney transplant recipients who underwent pyelovesicostomy between January 2000 and June 2023. The collected data included patient demographics, surgery indication, time from transplant to pyelovesicostomy, procedure details, and kidney function at various time points after surgery. Primary outcomes were allograft function and complications. RESULTS: The 5 patients (4 female, 1 male) had a mean age of 65.8 years and mean body mass index of 26.8. Indications were complex ureteral lesions. The time between transplant and reoperation ranged from 4 days to 12 years. Renal function improved for all patients, with a progressive decrease in mean serum creatinine concentration. The mean follow-up period extended to 7 years. One patient died with the graft still functional at 20 years after the operation, whereas the remaining 4 patients continue to live with functional grafts. CONCLUSIONS: Our study suggests that pyelovesicostomy may provide a potent alternative for the management of complex ureteral lesions after kidney transplant. We have observed good short-term and long-term outcomes in specific patients, pointing toward a promising avenue oftreatment worth further exploration. This reaffirms the importance of a personalized approach in medicine, to consider each patient's unique conditions and characteristics during therapeutic decisions.

Protection of the endothelium and endothelial glycocalyx by hydrogen against ischaemia-reperfusion injury in a porcine model of cardiac arrest.

BACKGROUND: Hydrogen is a potent antioxidant agent that can easily be administered by inhalation. The aim of the study was to evaluate whether hydrogen protects the endothelial glycocalyx layer after successful cardiopulmonary resuscitation (CPR). METHODS: Fourteen anesthetized pigs underwent CPR after induced ventricular fibrillation. During CPR and return of spontaneous circulation, 2% hydrogen gas was administered to seven pigs (hydrogen group) and seven constituted a control group. Biochemistry and sublingual microcirculation were assessed at baseline, during CPR, at the 15th, 30th, 60th, 120th minute. RESULTS: All seven subjects from the hydrogen group and six subjects in the control group were successfully resuscitated after 6-10 minutes. At baseline, there were no statistically significant differences in examined variables. After the CPR, blood pH, base excess, and lactate showed significantly smaller deterioration in the hydrogen group than in the control group. By contrast, plasma syndecan-1 and the measured variables obtained via sublingual microcirculation did not change after the CPR; and were virtually identical between the two groups. CONCLUSION: In pigs, hydrogen gas inhalation during CPR and post-resuscitation care was associated with less pronounced metabolic acidosis compared to controls. However, we could not find evidence of injury to the endothelium or glycocalyx in any studied groups.

Mapping Dysfunctional Circuits in the Frontal Cortex Using Deep Brain Stimulation.

Frontal circuits play a critical role in motor, cognitive, and affective processing - and their dysfunction may result in a variety of brain disorders. However, exactly which frontal domains mediate which (dys)function remains largely elusive. Here, we study 534 deep brain stimulation electrodes implanted to treat four different brain disorders. By analyzing which connections were modulated for optimal therapeutic response across these disorders, we segregate the frontal cortex into circuits that became dysfunctional in each of them. Dysfunctional circuits were topographically arranged from occipital to rostral, ranging from interconnections with sensorimotor cortices in dystonia, with the primary motor cortex in Tourette's syndrome, the supplementary motor area in Parkinson's disease, to ventromedial prefrontal and anterior cingulate cortices in obsessive-compulsive disorder. Our findings highlight the integration of deep brain stimulation with brain connectomics as a powerful tool to explore couplings between brain structure and functional impairment in the human brain.

Experimental Investigation and Control of a Hot-Air Tunnel with Improved Performance and Energy Saving.

The paper is focused on the identification, control design, and experimental verification of a two-input two-output hot-air laboratory apparatus representing a small-scale version of appliances widely used in the industry. A decentralized multivariable controller design is proposed, satisfying control-loop decoupling and measurable disturbance rejection. The proposed inverted or equivalent noninverted decoupling controllers serve for the rejection of cross-interactions in controlled loops, whereas open-loop antidisturbance members satisfy the absolute invariance to the disturbances. Explicit controller-structure design formulae are derived, and their equivalence to other decoupling schemes is proven. Three tuning rules are used to set primary controller parameters, which are further discretized. All the control responses are simulated in the Matlab/Simulink environment. In the experimental part, two data-acquisition, communication, and control interfaces are set up. Namely, a programmable logic controller and a computer equipped with the peripheral component interconnect card commonly used in industrial practice are implemented. A simple supervisory control and data acquisition human-machine interface via the Control Web environment is developed. The laboratory experiments prove better temperature control performance measured by integral criteria by 35.3%, less energy consumption by up to 6%, and control effort of mechanical actuator parts by up to 17.1% for our method compared to the coupled or disturbance-ignoring design in practice. It was also observed that the use of a programmable logic controller gives better performance measures for both temperature and air-flow control.

A porcine model of endothelial glycocalyx damage by enzymatic digestion: A pilot study.

BACKGROUND: The endothelial glycocalyx (EG) plays a vital role in the physiology and pathophysiology of human microcirculation. Having relevant EG damage model would be important tool for testing new interventions aiming at EG protection and recovery. We describe the first in vivo EG damage model in pig. OBJECTIVE: To investigate the course of animal EG damage induced by specific enzymes. MATERIAL AND METHODS: Four anesthetized piglets received enzymes: 1g hyaluronidase and 25 IU heparanase I intravenously. Blood and urine samples were collected at baseline and 20/40/60/80/100/120 min for detecting markers of endothelial and EG function. Sublingual microcirculation and EG thickness were assessed by Side-stream Dark Field (SDF) imaging and Perfused Boundary Region (PBR) respectively. EG of the mesentery artery was visualized in fluorescent microscopy. RESULTS: Biochemical marker of EG damage syndecan-1 showed temporary increase with return to baseline and was reflected by PBR values. Albumin levels suggested brief period of capillary leakage (decrease in the serum, increase in the urine) with a trend to normalization. Urine glycosaminoglycans peaked at 120 minutes. Microcirculatory perfusion parameter showed significant alteration. Diffusion parameters were altered with no statistical significance. CONCLUSION: EG damage induced by specific enzymes was reflected by temporary changes of biochemical makers together with alteration of microcirculation and changes in fluorescent microscopy of EG layer. Our results support to further validate presented model of EG damage on a larger number of animals.

Clinical physiology aspects of chloremia in fluid therapy: a systematic review.

BACKGROUND: This systematic review discusses a clinical physiology aspect of chloride in fluid therapy. Crystalloid solutions are one of the most widely used remedies. While generally used in medicine for almost 190 years, studies focused largely on their safety have only been published since the new millennium. The most widely used solution, normal saline, is most often referred to in this context. Its excessive administration results in hyperchloremic metabolic acidosis with other consequences, including higher mortality rates. METHODS: Original papers and review articles eligible for developing the present paper were identified by searching online in the electronic MEDLINE database. The keywords searched for included hyperchloremia, hypochloremia, and compound words containing the word "chloride," infusion therapy, metabolic acidosis, renal failure, and review. RESULTS: A total of 21,758 papers published before 31 May 2020 were identified; of this number, 630 duplicates were removed from the list. Upon excluding articles based on their title or abstract, 1850 papers were screened, of which 63 full-text articles were assessed. CONCLUSIONS: According to the latest medical concepts, dyschloremia (both hyperchloremia and hypochloremia) represents a factor indisputably having a negative effect on selected variables of clinical outcome. As infusion therapy can significantly impact chloride homeostasis of the body, the choice of infusion solutions should always take into account the potentially adverse impact of chloride content on chloremia and organ function.

Efficacy and Safety of AM-111 in the Treatment of Acute Unilateral Sudden Deafness-A Double-blind, Randomized, Placebo-controlled Phase 3 Study.

OBJECTIVE: To confirm the efficacy and safety of AM-111 (brimapitide), a cell-penetrating c-Jun N-terminal Kinase (JNK) inhibitor, in patients suffering from severe to profound acute unilateral idiopathic sudden sensorineural hearing loss (ISSNHL). STUDY DESIGN: Prospective, double-blind, randomized, placebo-controlled phase 3 study with follow-up visits on Days 3, 7, 28, and 91. SETTING: Fifty-one European and Asian sites (tertiary referral centers, private ENT practices). PATIENTS: Two hundred fifty-six patients aged 18 to 65 years presenting within 72 hours following ISSNHL onset with mean hearing loss ≥ 40 dB and mean threshold ≥ 60 dB at the 3 worst affected contiguous test frequencies. INTERVENTIONS: Single-dose intratympanic injection of AM-111 (0.4 or 0.8 mg/ml) or placebo; oral prednisolone as reserve therapy if hearing improvement < 10 dB at Day 7. MAIN OUTCOME MEASURES: Hearing improvement to Day 28 was the primary efficacy endpoint; complete hearing recovery, frequency of reserve therapy used, complete tinnitus remission, improvement in word recognition were secondary endpoints. Safety was evaluated by the frequency of clinically relevant hearing deterioration and adverse events. RESULTS: While the primary efficacy endpoint was not met in the overall study population, post-hoc analysis showed a clinically relevant and nominally significant treatment effect for AM-111 0.4 mg/ml in patients with profound ISSNHL. The study drug and the administration procedure were well tolerated. CONCLUSIONS: AM-111 provides effective otoprotection in case of profound ISSNHL. Activation of the JNK stress kinase, AM-111's pharmacologic target, seems to set in only following pronounced acute cochlear injury associated with large hearing threshold shifts.

Current vascular allograft procurement, cryopreservation and transplantation techniques in the Czech Republic.

BACKGROUND: Vascular allotransplantations are performed worldwide in selected patients suffering from vascular prosthesis infection or critical limb ischemia. Either fresh or cryopreserved vascular allograft may be used. OBJECTIVES: In various points, we address several aspects (allograft procurement, cryopreservation and transplantation technique) of the program of vascular allotransplantations in the Czech Republic. MATERIAL AND METHODS: Vascular grafts retrieval has been done within multiorgan harvests using no-touch technique. Very short time of cold ischemia is achieved due to close cooperation with Tissue Establishment where the following processing of cryopreservation is performed. Meeting all necessary quality criteria is a prerequisity for releasing grafts for clinical application. Standardized thawing protocol and surgical handling aims to minimize microfractures before implantation. RESULTS: Based on experimental and clinical work, the first validation of cryopreserved arterial and venous grafts for clinical use was performed between 2011 and 2013 in the Czech Republic. The developement of storage of vascular tissue in banks was stimulated in 2000-2010 by the issue of EU directives and national harmonized norms, aimed at assurance of high quality and safety of cells and tissues used for transplantations in humans. CONCLUSIONS: There are several crucial moments affecting final quality, including graft retrieval within a multiorgan harvest, short ischemic time, cryopreservation and thawing technique used. The recommended surgical handling during implantation may also affect results and graft-related complications.

Organization model for allotransplantations of cryopreserved vascular grafts in Czech Republic.

The transplantation of fresh or cryopreserved vascular allografts in patients with a prosthetic graft infection or critical limb ischemia is necessary for their limb salvage and, in many cases, represents a lifesaving procedure. While transplantation of fresh allografts has a long history in the Czech Republic, the standard use of cryopreserved vascular allografts was introduced into the clinical practice in 2011 as a result of the implementation of EU Directive 2004/23/EC into national legislation (Human Cell and Tissue Act No. 296/2008 Coll.). The authors present an organizational model based on cooperation between the majority of Czech Transplant Centers with a tissue establishment licensed by the national competent authority. In various points, we are addressing individual aspects of experimental and clinical studies which affect clinical practice. Based on experimental and clinical work, the first validation of cryopreserved arterial and venous grafts for clinical use was performed between 2011 and 2013. The growing number of centers participating in this programme led to a growing number of patients who underwent transplantation of vascular allografts. In 2015 the numbers of transplanted fresh versus cryopreserved allografts in the Czech Republic were almost equal. Cooperation of the participating centers in the Czech Republic with the licensed Tissue Establishment made it possible to achieve a full compliance with the European Union Directives, and harmonized national legal norms and assured a high quality of cryopreserved vascular allografts.

Human polyomavirus 9 in immunocompromised patients in the University Hospital in Hradec Kralove, Czech Republic.

Human polyomaviruses such as JC polyomavirus and BK polyomavirus have long been well known pathogens of immunocompromised patients. Several new members of this viral family have been described during the last decade. Human polyomavirus 9 seems to be a novel pathogen of transplanted patients according to some studies. The aim of our study was to determine the presence of human polyomavirus 9 in patients after kidney or stem cell transplantation (SCT) at the University Hospital in Hradec Kralove, Czech Republic. Overall 100 patients, 65 after kidney transplantation and 35 after SCT, were included into the study. At least three follow-up samples from each patient were examined for human polyomavirus 9 DNA presentation with the two previously described in-house PCR protocols. Despite the frequent reactivation of human CMV (14.3% in kidney transplantation and 63.3% after SCT) or BK polyomavirus in our patient group, there was no positivity for human polyomavirus 9 either in blood samples or urine samples. One of the possible reasons for this discrepancy versus previous published studies could be a relatively low proportion of patients treated by induction therapy before kidney transplantation in our study cohort.

Laparoscopic Left Renal Vein Transposition for Nutcracker Syndrome.

The left renal vein (LRV) reimplantation into the distal inferior vena cava is considered to be the gold standard of care for symptomatic nutcracker syndrome (NCS). The vast majority of these surgical procedures are performed by open surgery. Experiences with minimally invasive laparoscopic surgery in this field are very limited. We present a case of a 17-year-old boy with NCS in whom the transposition of the LRV was done laparoscopically. The patient suffered from left flank pain, painful left-sided varicocele, microscopic hematuria, proteinuria, and oligoasthenospermia. There were no intraoperative complications, and the postoperative course was uneventful. At 12-month follow-up, hematuria, left flank pain, and left testicular pain resolved. Duplex ultrasonography revealed patent LRV. Laparoscopic LRV transposition appears to be safe, feasible, and has favorable postoperative course.

The estimation of post-transplant lymphocele origin using creatine kinase activity.

INTRODUCTION: The aim of this research was to create a laboratory instrument for the estimation of post-transplant lymphocele origin. It is based on the enzymatic activity of creatine kinase (CK) in the lymphocele content. MATERIAL AND METHODS: A total of 120 lymph samples from different retroperitoneal regions were obtained from non-transplanted patients; equal numbers from the iliac region, renal cysts, and the subdiaphragmatic retroperitoneum. Activities of creatine kinase (CK) and gamma-glutamyl transpeptidase (GGT) were determined in all samples and statistically analyzed against their activity in serum from patients without surgery. RESULTS: Activities of CK in the pelvis, retroperitoneum, renal cysts, and serum were 5.06, 0.83, 6.48 (P<0.001), 2.50, 0.73, 3.60 (P<0.001), 0.02, 0.01, 0.05 (P<0.001), and 0.66, 0.41, 0.79 microkat/l, respectively. Activities of GGT in the same lymph samples were 0.26, 0.16, 0.36 (P=0.048), 0.41, 0.25, 0.48 (non-significant), 0.11, 0.07, 1.17 (P=0.003) and 0.34, 0.24, 0.55 microkat/l, respectively. A graph was constructed relating CK activity to lymph origin. CONCLUSION: Significantly different CK enzyme activity was observed in different regions of the retroperitoneum. The presented graph is a simple instrument for the estimation of the lymphocele content origin. The method requires percutaneous aspiration of the lymphocele and evaluation of the CK and GGT activity in the sample. From the graph the estimated proportion of renal lymph in the lymphocele can be read directly. This instrument can provide better understanding of post-transplant lymphocele fluid source.

Late toxicity after conformal and intensity-modulated radiation therapy for prostate cancer: impact of previous surgery for benign prostatic hyperplasia.

OBJECTIVES: To retrospectively compare late toxicity of conventional-dose three-dimensional conformal radiation therapy (3D-CRT) and high-dose intensity-modulated radiation therapy (IMRT) for prostate cancer. METHODS: A total of 340 patients with T1-3 prostate cancer were treated with 3D-CRT (n = 228) and IMRT (n = 112). The median follow-up time was 5.9 years and 3.0 years, respectively. The prescription dose was 70 Gy for 3D-CRT and 78 Gy for IMRT. Late gastrointestinal (GI) and genitourinary (GU) toxicities were graded according to the Fox Chase modification of the Radiation Therapy Oncology Group and Late Effects Normal Tissue Task Force criteria. RESULTS: There was no difference between 3D-CRT and IMRT in the incidence of GI and GU toxicity at 3 years. On multivariate analysis, transurethral resection of prostate/open transvesical prostatectomy (TURP/TVPE) for benign prostatic hyperplasia, carried out before radiotherapy, significantly increased the risk of Grade >or=2 GU toxicity (risk ratio 1.88). Among patients who experienced TURP/TVPE, the 5-year actuarial likelihood of Grade 2-3 urinary incontinence was 23%, compared with 9% for those without prostate surgery (P = 0.01). CONCLUSIONS: Tolerance of 3D-CRT and IMRT was similar, despite the use of high radiation dose with IMRT. Previous TURP/TVPE increased the risk of GU toxicity.

Bipolar transurethral resection of anastomotic strictures after radical prostatectomy.

PURPOSE: The efficacy of the bipolar endoscopic resection for anastomotic stricture was assessed and compared with holmium laser treatment. PATIENTS AND METHODS: We studied a cohort of 39 patients with anastomotic strictures in years 1999 to 2007. Twenty-two patients had undergone bipolar resection, and 17 patients had undergone holmium laser treatment. The mean age of the bipolar cohort was 63.8 years; initial prostate-specific antigen (PSA) level was 10.7 ng/mL. The mean age of the laser cohort was 64 years; initial PSA level was 7.8 ng/mL. The results were evaluated by measurement of the maximum urinary flow (Qmax) and the postvoid residual volume of urine (PVR) before surgery, and at 6 weeks and 6 months after surgery. The Wilcoxon rank-sum test was used for statistical analysis, and a P value <0.05 was considered significant. RESULTS: The mean follow-up period was 42 (14-74) months. Improvements in Qmax and PVR were recorded in the two cohorts. In the bipolar cohort, the mean values of Qmax were 3.9 mL/s, 14 mL/s, and 13 ml/s, while PVR values were 46 mL, 10 mL, and 11 mL. The mean values of Qmax in the laser cohort were 3.7 mL/s, 11 mL/s and 6.1 mL/s; PVR were 25 mL, 16 mL, and 19 mL. Statistically significantly better results of Qmax over 6 months were in the bipolar cohort (P < 0.001). No perioperative complications and no deterioration of urinary continence were recorded. CONCLUSION: The bipolar resection of an anastomotic stricture is a highly effective method that produces better long-term results than the holmium laser treatment.

Cyclosporine, tacrolimus and sirolimus retain their distinct toxicity profiles despite low doses in the Symphony study.

BACKGROUND: Reducing side effects of immunosuppressive regimens has become a priority in transplantation medicine because of the large number of patients and grafts that succumb to infection in the short term and cardiovascular disease in the long term. The Symphony study was a 12-month prospective, randomized, open-label, multi-centre, four parallel arm study that aimed to evaluate the safety and efficacy of low-dose immunosuppressive regimens compared with a standard-dose regimen in renal transplant recipients. This sub-analysis focuses on specific toxicities observed with the low-dose regimens. METHODS: Adult patients (n = 1645) scheduled to undergo renal transplantation received low-dose cyclosporine (CsA), tacrolimus (Tac) or sirolimus (SRL) in addition to daclizumab induction or standard-dose cyclosporine without induction. All patients received mycophenolate mofetil and corticosteroids. We evaluated the incidence of adverse events (AEs), tested specific group differences and assessed the relationship of selected AEs with drug levels. RESULTS: The four arms had similar incidences of AEs, but serious AEs were more common with low-dose SRL and led to more discontinuations. Infections were the most common AEs, with the highest incidence in the standard-dose CsA group, in particular, cytomegalovirus (CMV) infections. Low-dose Tac had the most reports of new-onset diabetes, leucopenia and diarrhoea. Low-dose SRL negatively influenced triglycerides, wound healing, lymphocele and anaemia. We found only weak relationships between specific AEs and drug levels. CONCLUSIONS: Despite the low doses, CsA, Tac and SRL retained distinct and different toxicity profiles. These findings may be of relevance for tailoring specific immunosuppressive regimens to patients with particular needs.

Effective treatment of mild-to-moderate nasal polyposis with fluticasone delivered by a novel device.

OBJECTIVE: To assess the efficacy and safety of fluticasone propionate administered using OptiNose's novel delivery device (Opt-FP) in subjects with bilateral mild-to-moderate nasal polyposis. METHODS: A prospective, multicentre, randomized, double-blind, placebo-controlled, parallel group study was conducted in adult subjects (n = 109) with mild-to-moderate bilateral nasal polyposis. Subjects received Opt-FP 400 microg or placebo twice daily for 12 weeks. Endpoints included endoscopic assessment of polyp size using Lildholdt's Scale, peak nasal inspiratory flow (PNIF), symptom scores and use of rescue medication. RESULTS: The proportion of subjects with improvement in summed polyp score >or= 1 (Lildholdt\'s Scale) was significantly higher with Opt-FP compared with placebo at 4, 8 and 12 weeks (22% vs 7%, p = 0.011, 43% vs 7%, p < 0.001, 57% vs 9%, p < 0.001). After 12 weeks the summed polyp score was reduced by 35% (-0.98 vs +0.23, p < 0.001). PNIF increased progressively during Opt-FP treatment (p < 0.05). Combined symptom score, nasal blockage, discomfort, rhinitis symptoms and sense of smell were all significantly improved. Rescue medication use was lower (3.1% vs 22.4%, p < 0.001). Opt-FP was well tolerated. CONCLUSIONS: Fluticasone propionate (400 microg b.i.d.) administered using OptiNose's breath actuated bi-directional delivery device was an effective and well tolerated treatment for mild-to- moderate bilateral nasal polyposis.