An original method for the evaluation of in vivo controlled release of the ceramic materials.

In recent years, the use of ceramic materials in orthopaedics and dentistry is becoming increasingly popular. However, it is important to know their biological and mechanical properties to optimize their use. The aim of this study is to describe a specific method to assess in vivo the effects of chronic release of ceramic materials implanted, in relation also to the type of material, pellets or powders. This was achieved by implanting ceramic powders and pellets, formed by low cohesion grains, in the patellar tendon of 48 New Zealand adult rabbits (24 with powders and 24 with pellets). The motion of the joint allowed easily and progressively the release of grains, detached from surface of the pellets and released to the joint space. Animals were sacrificed at different intervals (1, 3, 6, 12 months). Retrieved knee joints underwent X-Ray, histological and ultrastructural analysis.

Zirconia toughened alumina (ZTA) powders: ultrastructural and histological analysis.

Ceramic materials, as Alumina and Zirconia, has made an improvement in the choice of new biomaterials for the load bearing application in dental and orthopaedic implants. These materials has shown mechanical resistance to high stress related to weight bearing and low debris in time. For this reason they are indicated on young patients implant, with high demanding activities and long life expectance. In literature however the risk of chronic inflammation due to chronic wear debris release and the possibility of carcinogenesis, is still to be definitively investigated. Another point to investigate is the acute reaction of the tissue in case of acute release of powders of these materials. The aim of this study was to investigate the possible local and systemic acute effects of ceramic precursors in form of powders of different size when released into articular joint. Powders of ZTA were implanted in the knee joint of twenty-four New Zealand white adult rabbits, that were sacrificed at 1,3,6, and 12 months. Radiographic, histological and immunoistochemestry analysis were conducted on periprosthetic tissue and peripheral organs, to verifying local host response and systemic toxic effects.

[Second-line therapy of idiopathic detrusor overactivity. Sacral neuromodulation and botulinum toxin A]. / Second-line-Therapie der idiopathisch überaktiven Blase. Sakrale Neuromodulation und Botulinumtoxin A.

The syndrome of idiopathic overactive bladder (I-OAB) impairs quality of life for the affected individuals. Conservative treatment options such as antimuscarinics are not always effective, and resulting side effects can lead the patient to stop treatment. In recently years, minimally invasive and reversible sacral neuromodulation and botulinum toxin A have become available. Currently, the approved treatment option for I-OAB that is recommended by the International Consultation on Incontinence is sacral neuromodulation by InterStim therapy. This article gives an overview of the present clinical evidence on the effectiveness and reliability of these two treatment modalities as well as the current significance of sacral neuromodulation and botulinum toxin A for the second-line treatment of adult I-OAB.

[Update on the second line management of idiopathic overactive bladder]. / Le point sur les traitements de seconde ligne de l'hyperactivité vésicale idiopathique.

The overactive bladder syndrome (OAB) negatively affects the daily life of many people worldwide and conservative treatments, such as antimuscarinics, not always bring relief and/or are associated with considerable side effects resulting in treatment failure. Second line treatment options used to be invasive surgical procedures. However, less radical, minimally invasive and reversible alternatives, such as sacral neuromodulation and botulinum toxin A have emerged. Of these, only sacral neuromodulation with InterStim Therapy has been approved for OAB and been recommended by the International Consultation on Incontinence (ICI) in 2004. Nevertheless, depending of country rules and habits, both seem to be used by urologists in clinical practice for treating idiopathic OAB (I OAB). Therefore, this review attempts to provide an update on the available clinical evidence concerning the efficacy and safety, and the current position of sacral neuromodulation and botulinum toxin A in the second line management of adults with I OAB.

Neurophysiological evidence may predict the outcome of sacral neuromodulation.

PURPOSE: Chronic stimulation of the sacral nerves has now become one of the most accepted stimulation therapies for functional lower urinary tract symptoms refractory to conservative treatment. Despite the existence of a large amount of literature on sacral neuromodulation (SNM) showing a fairly high percent of significant improvement in clinical outcome there are few experimental studies of SNM stimulus parameters and/or neurophysiological monitoring. We evaluated the specific action of SNM on the primary sensory cortical area. Somatosensory evoked potentials (SEPs) of the pudendal and posterior tibial nerves were evaluated in patients implanted with a monolateral permanent quadripolar electrode. MATERIALS AND METHODS: A total of 24 patients underwent stage 1 monolateral sacral nerve implantation. Three SEP patterns were evaluated; namely before implantation, 1 month after stage 1 with stimulation set at 21 Hz and again with a pulse rate of 40 Hz. RESULTS: In all patients SNM produced a significant decrease in pudendal SEP latency of the first positive deflection between baseline SNM stimulation at different pulse rates at the ipsilateral and contralateral implant sites. This finding was evidence of the effect of S3 SNM on the cortical sensory area and the specificity of pudendal SEPs in measuring how SNM modulates the afferent pathway from the spinal nerve to the cortical sensory area. CONCLUSIONS: Our study confirms previous observations that SNM acts by the afferent pathway at the cortical site level and it sheds light on so-called idiopathic lower urinary tract symptoms. A modification of SEPs induced by SNM seems to be a prognostic factor of clinical outcomes. The action of SNM on the afferent pathway from the sacral area to the somatosensory cortex is specific and neurophysiological evaluation via pudendal SEPs provides evidence to this effect.

Sacral neuromodulation and pregnancy.

PURPOSE: Sacral neuromodulation is effective for lower urinary tract dysfunction. However, despite its increasing use and a preponderance of female patients treated to our knowledge its effect in pregnant women and developing fetuses remains unknown. Therefore, we obtained information on patients on sacral neuromodulation who then achieved pregnancy. MATERIALS AND METHODS: Data were obtained using a standard questionnaire from 4 physicians with a total of 6 eligible patients. We recorded patient urological history, indication for neuromodulation, pregnancy course, the mode of delivery and neonatal health. We also noted the timing of implant deactivation and reactivation. RESULTS: In 5 patients the stimulator was deactivated between weeks 3 and 9 of gestation, after which 2 with a history of urinary retention had urinary tract infection. In another case, stimulation was discontinued 2 weeks before conception. The only noted complication developed in a pregnancy in which birth was premature at 34 weeks. Three patients underwent normal vaginal delivery, including 1 in whom subsequent implant reactivation did not resolve voiding dysfunction. In 3 cases elective cesarean section was performed. All neonates were healthy. CONCLUSIONS: When a patient on neuromodulation achieves pregnancy, the stimulation should be deactivated. If implant deactivation leads to urinary related complications that threaten the pregnancy, reactivation should be considered. Elective cesarean section should be discussed since it is possible for sacral lead damage or displacement to occur during vaginal delivery.

Quality of life assessment in patients who undergo sacral neuromodulation implantation for urge incontinence: an additional tool for evaluating outcome.

PURPOSE: We investigated the impact of sacral neuromodulation on quality of life and assessed the importance of quality of life for determining the success of sacral neuromodulation in patients with detrusor hyperactivity, including instability and hyperreflexia. We also compared it with parameters documented in a voiding diary. MATERIALS AND METHODS: From May 1998 to December 2000, 82 female and 31 male patients 17 to 79 years old (mean age 51.1) with urge incontinence (63), urgency/frequency (5), voiding disturbance (41) and pelvic pain (4) resistant to conservative treatment were enrolled in a national prospective registry after showing a positive response to percutaneous nerve evaluation testing. Of the patients 47 who were 32 to 79 years old (mean age 59.2) with urge incontinence due to detrusor instability and 16 who were 27 to 51 years old (mean age 51.5) with hyperreflexia were asked to complete a validated self-reporting incontinence domain specific quality of life questionnaire before, and 3, 6, 9, 12, 18, 24 and 36 months after implantation. RESULTS: Compared with baseline the quality of life index significantly improved at each followup, which strongly correlated with the decrease in the number of incontinence episodes. CONCLUSIONS: Evaluating quality of life may be an additional useful tool for assessing the results of sacral neuromodulation for urge incontinence. Our study confirms that sacral neuromodulation is effective therapy for urge incontinence that can have a positive effect on patient quality of life.

Chronic sacral neuromodulation in patients with lower urinary tract symptoms: results from a national register.

PURPOSE: The Italian Register was created in February 1997 to collect the national results of sacral neuromodulation. All Italian centers at which sacral neuromodulation is performed were invited to participate in our study. We present the results from retrospective and prospective registers. MATERIALS AND METHODS: A total of 196 patients underwent permanent implantation of sacral neuromodulation and were enrolled in the Italian register. There were 18 males and 75 females in the retrospective, and 28 males and 75 females in the prospective studies. Student's t test was used to compare paired values, and the Wilcoxon rank sum and nonparametric tests were used when necessary. RESULTS: Mean incontinent episodes daily plus or minus standard deviation for patients with detrusor instability went from 5.4 +/- 3.9 to 1.1 +/- 1.6 (median 5 and 0, respectively) at 12-month followup (p <0.001). For idiopathic retention average residual volume decreased from 277 to 108 cc (median 287 and 80, respectively), and 50% of patients stopped catheterization and another 13% catheterized once daily at 1-year after implantation. With neurogenic voiding disturbances, the results fluctuated with time from a minimum of 33% to a maximum 66% of patients who did not catheterize at 6-month followup and 12 months after implantation, respectively. At 12-month followup, 50% of patients with hyperreflexia had less than 1 incontinent episode daily. The problem was completely solved in 66% of patients in the retention group. Of patients in the urge incontinent population 39% were completely dry and 23% had less than 1 incontinent episode daily. CONCLUSIONS: Sacral neuromodulation is effective therapy for treating lower urinary tract symptoms resistant to less invasive therapy.

Urodynamic assessment during intravesical infusion of capsaicin for the treatment of refractory detrusor hyperreflexia.

PURPOSE: Parameters to predict outcome and the urodynamic effects during infusion of capsaicin, seem not to have been assessed in patients with chronic cord injury. We monitored bladder activity urodynamically during infusion of high dosage of capsaicin. MATERIAL AND METHODS: Thirty patients, 18 women and 12 men (average age 29 years, range 20-59 years), suffering from chronic spinal myelopathy, who presented a refractory detrusor hyperreflexia, were studied. They received saline solution containing 10(-3) M capsaicin at a flow rate of 2 ml min(-1) for 15 min (total volume 30 c.c.). The detrusor activity was monitored by a real-time cystometrogram during infusion and 15 min after the end of the infusion itself. New filling cystometrograms were recorded after 30 days and after 6 months. RESULTS: We obtained a clinical and significant urodynamic improvement in 15 of the 30 patients (50%), confirming that intravesical capsaicin may represent a therapeutic option for a selected group of patients suffering from refractory detrusor hyperreflexia due to chronic spinal upper motor neuron lesion. Best results were observed in patients who showed, during the infusion of capsaicin, early uninhibited bladder contractions which disappeared within 10-12 min from the beginning of the infusion (desensitisation). The patients of this group presented a significant increase of mean cystomanometric capacity after 6 months (from 190.7 to 396.7 ml). No significant clinical or urodynamic improvement was observed in the group of patients in whom uninhibited activity of detrusor was recorded for all the time of infusion. CONCLUSION: Our results support the idea of a major complexity of spinal reflex in paraplegic patients and may offer a clue to explain the failure of therapy with capsaicin. The present results support a new approach in the treatment of detrusor hyperreflexia. The ideal dosage and treatment interval are not at present established and further studies are needed to explain substantial differences in the outcome according to different urodynamic responses.

Intravesical resiniferatoxin for the treatment of detrusor hyperreflexia refractory to capsaicin in patients with chronic spinal cord diseases.

OBJECTIVE: Resiniferatoxin (RTX), a substance isolated from some species of Euphorbia, a cactus-like plant, shows pharmacological effects similar to those of capsaicin. We have studied the possibility of treating detrusor hyperreflexia refractory to intravesical capsaicin in patients with chronic spinal cord injuries, thereby providing insight into the mechanism of action of RTX on sensory neurons and its possible future pharmacological and clinical use. MATERIALS AND METHODS: RTX saline solution (30 ml at a concentration of 10(-5) M) was instilled into the bladder of 7 patients with detrusor hyperreflexia, refractory to intravesical capsaicin therapy, and left in place for 30 min. Effects on bladder function were monitored during the treatment and at follow-up (15 days and 4 weeks later). RESULTS: Fifteen days after RTX, the mean cystomanometric capacity increased significantly from 190 ml +/- 20 ml to 407.14 ml +/- 121.06 (p < 0.01), and it remained high four weeks later (421.66 +/- 74.40 p < 0.01). After 15 days, four patients had a pharmacologically induced detrusor areflexia. They emptied their bladders by clean intermittent catheterization. After four weeks, only two patients still had a pharmacologically induced detrusor areflexia. Clinically, three patients remained dry, and the other three reported a significant improvement in their incontinence and symptoms (frequency, urgency and nocturia). CONCLUSIONS: By interfering with sensory unmyelinated fibers, intravesical RTX seems to be a promising treatment option for selected cases of detrusor hyperreflexia. The ideal dosage and treatment interval have not yet been established, and further studies are necessary to confirm our preliminary results.