The role of spinal cord tractography in detecting lesions following selective bladder afferent and efferent fibers injury: A novel method for induction of neurogenic lower urinary tract dysfunction in rabbit.

OBJECTIVE: Neurogenic lower urinary tract dysfunction (NLUTD), a challenging disorder, is defined by lack of bladder control due to the abnormalities in neural pathways and can be classified based on the location of lesions within the nervous system, thus investigating the neural pathways can help us to know the site of the lesion and specify the class of the NLUTD. Diffusion Tensor Imaging (DTI) tractography, a noninvasive advanced imaging method, is capable of detecting central nervous system pathologies, even if routine magnetic resonance imaging shows no abnormality. Accordingly, tractography is an ideal technique to evaluate patients with NLUTD and visualize the pathology site within the spine. This study aimed to introduce a novel method of spinal cord injury (SCI) to establish NLUTD in the rabbit and to investigate the potential of tractography in tracing neural tracts of the spinal cord in an induced NLUTD animal model. MATERIALS AND METHODS: An animal model of NLUTD was induced through cauterization of the spinal cord at the level T12-L1 in 12 rabbits. Then rabbits were assessed via DTI, urodynamic studies (UDS), voiding cystourethrogram (VCUG), and pathology assessments using antineurofilament 200 (NF200) antibody, anti-S100, anti-Smooth Muscle Actin, anti-Myogenin, and anti-MyoD1. RESULTS: The tractography visualized lesions within spinal cord fibers. DTI parameters including fractional anisotropy (FA) value and tract density were significantly decreased (FA: p-value = 0.01, Tract density: p-value = 0.05) after injury. The mean diffusivity (MD) was insignificantly increased compared to before the injury. Also, the results of UDS and pathology assessments corroborated that applying SCI and the establishment of the NLUTD model was completely successful. CONCLUSION: In the present study, we investigated the auxiliary role of tractography in detecting the spinal cord lesions in the novel established rabbit model of NLUTD. The introduced method of NLUTD induction was without the leg's neurological deficit, easily applicable, low-cost, and was accompanied by minimal surgical preparation and a satisfactory survival rate in comparison with other SCI animal models.

Management of urinary and bowel dysfunction in rabbit model of spinal cord injury using Schwann cells and muscle progenitors: functional study and evidence for novel mechanism of action.

PURPOSE: We tried to investigate the role of Schwann and satellite cells in the treatment of neurogenic bladder and bowel dysfunction; following spinal cord injury in the rabbit model. METHODS: Twelve male New Zealand rabbits underwent induction of neurogenic bladder by spinal cord injury. Rabbits underwent the fiber tractography analysis to confirm the induction of spinal cord injury. Then, animals were randomly divided into two groups. In group I (n = 4), Schwann cells were obtained from autologous peroneal nerve. In group II (n = 4), the co-culture of nerve-muscle cells was obtained from autologous peroneal nerve and quadriceps muscle. Animals in the control group (n = 4) did not undergo any rehabilitation therapy. One and 4 months after injection of cells into the external anal sphincter, electromyography, urethral pressure profiles, urodynamic studies, voiding cystourethrogram, and manometry was performed to confirm the efficacy of treatment in short- (1 month) and long-term (4 months) follow-ups. RESULTS: The investigations validated that no statistically significant difference was detected between the two experimental groups in a short-term follow-up (p-value > 0.05). However, the functional features were improved in group II in long-term follow-up. In both groups, the external anal sphincter contracted in response to electrical signals delivered to the muscle. However, more signals were detected in group II in electromyography evaluation. The immunohistochemical staining demonstrated that the histological features of the bladder and spinal cord were more satisfactory in group II in all follow-ups compared to group I, in terms of less edema, inflammation, presence of progenitor cells, and expression of muscle and nerve markes. CONCLUSION: Our results suggested that the injection of nerve-muscle co-culture cells into the external anal sphincter may be a helpful tactic for ameliorating the urological complications; following spinal cord injury induction in the rabbit model.

Intrarectal Electromotive Botulinum Toxin Type A Administration in Children With Intractable Constipation: A Randomized Clinical Trial.

INTRODUCTION: Children with refractory constipation might not respond to conventional medical treatments. In this study, we assessed the effectiveness of intrarectal botulinum toxin type A/electromotive drug administration (BoNTA/EMDA) on constipation in these children and compared its efficacy with routine intrasphincteric BoNTA injection. METHODS: From 2017 to 2019, 60 children aged 5-13 years who fulfilled Rome III criteria for intractable constipation were enrolled and randomly assigned into 2 treatment groups. EMDA group (n = 30) underwent BoNTA/EMDA, whereas the control group (n = 30) received injection of BoNTA into the internal anal sphincter. A complete bowel habit diary (with data on the frequency of defecation per week, stool form, and the number of fecal soiling episodes), a constipation score questionnaire, and a visual pain score were recorded before treatment and at 1 month and 6 months after treatment. In addition, children in both groups were assessed with a constipation-related quality of life questionnaire. RESULTS: After 1-month follow-up, treatment reduced the number of patients fulfilling the diagnostic criteria in both EMDA (24/30, 80%) and injection (25/30, 83.3%) groups (P < 0.001). The stool form was normalized in 73.3% (22/30) in EMDA group and 80% (24/30) in injection group after treatment. The median of constipation score and pain score decreased significantly in both groups after treatment (P < 0.001 and P < 0.001, respectively). DISCUSSION: BoNTA/EMDA seems to be as effective as intrasphincteric BoNTA injection for treatment of intractable constipation. In addition, this technique is associated with less comorbidity, is less costly, and can be performed in an office-based setting without general anesthesia.

Intravesical Electromotive Botulinum Toxin Type A (Dysport) Administration in Children With Myelomeningocele.

OBJECTIVE: Electromotive drug administration (EMDA) presents a minimally invasive method of intravesical instillation of therapeutic agents without the need for general anesthesia.1 It employs a combination of iontophoresis, electrophoresis, and electroporation to deliver drugs into deep tissue layers using an electrical current created between 2 electrodes.2 This video shows feasibility of botulinum toxin type A (BoNTA) EMDA in myelomeningocele children with urinary incontinence secondary to neuropathic detrusor overactivity. METHODS: In this technique (Video 1), catheterization was performed with a 10-Fr (CE-DAS, UROGENICS/Ag 9900 (pediatric), Mirandola, Italy) catheter electrode, after providing a local transurethral anesthesia with 2% lidocaine gel. The cuff of the catheter was filled by 2 cc saline solution. The bladder was then drained and irrigated with 0.9% saline solution until the catheter outflow became clear. The bladder was subsequently filled with sterile water to its maximal capacity. BoNTA (Dysport) at a dose of 10 IU/kg was added to the intravesical solution. Negative electrode as 2 dispersive electrodes was placed on the abdomen. Positive electrode was connected to the intravesical catheter. A pulsed current generator (Physionizer 30, Physion srl, Mirandola, Italy), delivered a current with frequency of 2,800 Hz, interval of 50 µs and amplitude of 10-20 mA for 20 minutes. At the end of the procedure, the bladder was emptied. RESULTS: For the first time, BoNTA/EMDA was performed on myelomeningocele patients with urinary incontinence in our center.3 According to our prior reports, urinary incontinence improved in 75% of the patients between 2 consecutive clean intermittent catheterizations at 1-year follow-up.4 Mean maximal cystometric capacity significantly increased from 148 ± 62 mL at baseline to 239 ± 73 mL 1 year after the treatment.4 CONCLUSION: This technique is a feasible, safe, reproducible, cost effective, long lasting, and pain free method, on an outpatient basis with long-term duration of effects and without anesthesia or cystoscopy procedure.

Alleviation of Cyclophosphamide-induced Hemorrhagic Cystitis by Dietary Pomegranate: A Comparative Experimental Study With Mesna.

In this study, we investigated the effects of pomegranate on alleviating cyclophosphamide-induced hemorrhagic cystitis (HC). Initially, 16 Sprague-Dawley rats were allocated into 4 groups: group 1 (control), group 2 (CP) in which HC was induced by cyclophosphamide; group 3 (CP+M), HC-induced rats that received Mesna regimen, and group 4 (CP+P), which compromised rats that had been on a 14-day diet of pomegranate juice before HC induction. Cystometry was performed a few hours before euthanasia; after euthanasia, aortic blood samples and bladder tissue samples were obtained to perform TUNEL assay, and histopathologic and biochemical assessments. Urodynamic findings revealed that mean detrusor pressure in CP+P was significantly lower compared with that in CP and CP+M (P<0.05). Histopathologically, urothelium destruction and inflammation were lower in CP+P and CP+M compared with that in CP. Collagen destruction was less prominent in CP+P compared with that in CP and CP+M. Tissue and plasma levels of malondialdehyde were significantly lower in CP+P versus CP (P<0.05). Catalase activity and total protein thiol group levels in plasma and bladder tissue were higher in CP+P versus CP (P<0.05). The TUNEL positivity in CP+P was significantly weaker than that in CP, indicating less DNA fragmentation and apoptosis. Pomegranate's characteristics could significantly affect the inflammatory and destructive process of hemorrhagic cystitis.

A Novel Method of Urinary Sphincter Deficiency: Serial Histopathology Evaluation in a Rat Model of Urinary Incontinence.

In this study, a novel technique of irreversible sphincter deficiency by pudendal nerve transection (PNT) using 40 female rats for studying the pathophysiology of stress urinary incontinence associated with childbirth was developed. Of the 40 rats, 10 served as controls and the remaining underwent bilateral PNT at the anastomotic lumbosacral trunk level. Urethral morphological changes following bilateral PNT were assessed with serial hematoxylin and eosin (H&E) and immunohistochemistry (IHC) staining methods at 50, 90, and 130 days post-intervention. Leak point pressure (LPP) measurement was used to determine the effect of pudendal injury on urethral outlet resistance after the transection. H&E and IHC staining showed irreversible loss of striated muscle mass of the sphincter region and increase in collagen deposition compatible with muscle atrophy. LPP measurements also significantly decreased following bilateral PNT. In conclusion, a novel method of irreversible sphincter insufficiency was developed. This model effectively decreased urethral outlet resistance and caused irreversible striated muscle atrophy. It was suggested that this technique can be used to develop a permanent sphincter deficiency model for the preclinical testing of treatment modalities exclusively triggering the pudendal nerve.