End-to-side neurorrhaphy: an experimental study in rabbits

The concept of end-to-side nerve repair was recently introduced; however, most authors have reported conflicting results with this technique. This study was conducted to assess the effectiveness of end-to-side nerve repair in both fresh and predegenerated specimens by histological evaluation in an animal study in rabbits. Thirty male rabbits were divided into three groups. In group 1 (n = 14), the peroneal nerve was divided and sutured end-to-side to the tibial nerve via an epineurial window. In group 2 (n = 13), the peroneal nerve was divided and sutured end-to-side to the tibial nerve after a 1-week "predegeneration period." In group 3 (n = 3), which was considered the control group, the peroneal nerve was divided and sutured to the adjacent soft tissues. After 3 months, specimens were harvested for histological evaluation. Nerve fiber count, in normal peroneal nerves, averaged 532/cross section. In groups 1 and 2, average nerve fiber count in implanted peroneal nerves was 6.24 and 7.00/cross section, respectively. No significant statistical difference was observed between fresh and "predegenerated" groups (P = 0.90). These data suggest that collateral sprouting of donor nerves is possible after end-to-side neurorrhaphy through an epineurial window, but the number of nerve fibers in recipient nerves is too low to result in any functional recovery in the target organ.     

Symphysiotomy: a viable approach for delayed management of posterior urethral injuries in children

PURPOSE: The outcome of symphysiotomy for accessing pelvic fracture related, obliterative urethral strictures is described. MATERIALS AND METHOD: In 7 boys and 3 girls 4 to 13 years old (mean age 6) surgical correction of a pelvic fracture related, obliterative urethral stricture was achieved through symphysiotomy. The stricture involved a prostatomembranous location in boys and complete vesicourethral distraction in girls. Patients were followed an average of 2.5 years (range 6 months to 4 years) by physical examination, urethrography and endoscopy. RESULTS: The stricture was successfully corrected in all patients and all void with a normal flow. All boys are continent but 2 of the 3 girls had early incontinence, which resolved with time in 1. In 2 of the 10 cases a previous attempt at perineal repair had already failed. No patient required urethrotomy or dilation and none had significant hemorrhage, fistulization, bladder hernia, chronic pain or secondary gait disturbance. CONCLUSIONS: Symphysiotomy is hereby revisited as a simple and effective approach for repairing traumatic posterior urethral injuries in the pediatric population. It can be performed instead of transpubic urethroplasty to manage long or otherwise complicated strictures.     

Serum zinc and copper levels in children with chronic renal failure

We evaluated changes in serum zinc (Zn) and copper (Cu) levels in two groups of children with chronic renal failure (CRF) – children with CRF who were on regular hemodialysis (Group 1, n=40) and children with CRF who were on conservative management (Group 2, n=31) – and in one group of healthy children (Group 3, n=30). All of the participants in the study were between 5–18 years old, and the composition of the three groups was almost identical with respect to age and sex. The length of time the children in Group 1 had been on hemodialysis varied between 3 and 52 months (mean: 20.97±14.8 months). To evaluate the impact of the duration of dialysis on serum levels of Zn, we further sub-divided Group 1 patients into two subgroups: Subgroup A patients (n=20) had been on hemodialysis therapy for less than 18 months (mean: 8.85±4.83 months); Subgroup B patients (n=20) had been on hemodialysis therapy for longer than 18 months (mean: 33.1±10.86 months). The PIXE (proton-induced X-ray emission) was used for measuring the trace elements. Results: The mean serum level of Zn was lower in the Group 1 (hemodialysis group) children than in the children of Group 2 (on conservative management) and group 3 (healthy children) (p<0.001), but the difference was not significant between Groups 2 and 3. No significant differences in serum levels of Cu were found among the three groups. The serum level of Zn was lower in Subgroup B than in Subgroup A (p<0.001). The correlation test showed that there was an inverse linear relation between the length of time the child was on the hemodialysis regimen and serum Zn levels. Conclusion: Chronic hemodialysis may lead to abnormalities in the serum levels of some trace elements in children with CRF that increase in severity with increasing duration of hemodialysis. Deficiencies of these trace elements – zinc in particular – may contribute to various conditions and symptoms in children undergoing chronic hemodialysis.     

Ultrasound examination and localization of the sciatic nerve: a volunteer study

BACKGROUND: Few studies have examined the use of ultrasound for sciatic nerve localization. The authors evaluated the usefulness of low-frequency ultrasound in identifying the sciatic nerve at three locations in the lower extremity and in guiding needle advancement to target before nerve stimulation. METHODS: In this prospective observational study, 15 volunteers underwent sciatic nerve examination using a curved ultrasound probe in the range of 2-5 MHz and a Philips-ATL 5000 unit (ATL Ultrasound, Bothell, WA) in the gluteal, infragluteal, and proximal thigh regions. Thereafter, an insulated block needle was advanced inline with the ultrasound beam to reach the nerve target, which was further confirmed by electrical stimulation. The quality of sciatic nerve images, ease of needle to nerve contact, threshold stimulating current, and resultant motor response were recorded. RESULTS: The sciatic nerve was successfully identified in the transverse view as a solitary predominantly hyperechoic structure on ultrasound in all of the three regions examined. The target nerve was visualized easily in 87% and localized within two needle attempts in all patients. Nerve stimulation was successful in 100% after two attempts with a threshold current of 0.42 +/- 0.12 (mean +/- SD) eliciting foot plantarflexion or dorsiflexion. CONCLUSIONS: These preliminary data show that a curved 2- to 5-MHz ultrasound probe provides good quality sciatic nerve imaging in the gluteal, infragluteal, and proximal thigh locations. Ultrasound-assisted sciatic nerve localization is potentially valuable for clinical sciatic nerve blocks.     

Cardiac MR assessment of cardiac myxomas

Cardiac myxomas are the most common benign primary cardiac tumour to present in adulthood. While most patients present with symptoms of cardiac obstruction, embolic phenomena or constitutional impairment, up to a fifth of patients remain asymptomatic and are incidentally diagnosed on imaging. Although echocardiography is usually the initial imaging modality used to evaluate these patients, cardiac MRI (CMR) has emerged over the past decade as the primary imaging modality in the assessment of patients with cardiac tumours. The superior tissue characterization capability of CMR means that it is able to determine the nature of some tumours pre-operatively and performs well in differentiating myxomas from thrombus. We present a pictorial review highlighting the key CMR features of myxomas and show how these lesions can be differentiated from thrombus and other cardiac masses.Primary cardiac tumours are uncommon with a reported prevalence at autopsy of 0.002%.¹ The majority are benign, with myxomas accounting for almost 50% of all primary cardiac tumours.² Myxomas are more common in female patients, and while they can occur at any age, they usually present in adults between the fourth and seventh decades of life.^3,4 Most patients typically present with at least one manifestation of the classic triad of cardiac obstructive symptoms, embolic phenomena and constitutional symptoms, but 20% are identified in asymptomatic patients as an incidental imaging finding.³Echocardiography is usually the initial imaging modality used in the assessment of a suspected cardiac mass but remains rather operator dependent with a restricted field of view and can be particularly challenging in patients with large body habitus.^2,4,5 Cardiac MRI (CMR) enables accurate assessment of the location and functional impact of cardiac masses in any imaging plane without exposing patients to ionizing radiation.^2,5 In particular, CMR performs better than echocardiography at determining the nature of cardiac lesions and can differentiate myxomas from thrombus.^2,5 Given that most cardiac lesions are not easily amenable to catheter-directed biopsy, accurate imaging differentiation of cardiac myxomas from other types of cardiac masses is of vital importance in guiding further management.     

The natural history of renal function following orthotopic heart transplant

BACKGROUND: The outcome of solid organ transplantation has dramatically improved after the introduction of the calcineurin inhibitor cyclosporine. With the increasing longevity of heart transplant recipients, the long-term effects of cyclosporine on renal function have become more evident. The natural history of kidney function following orthotopic heart transplant is not well defined and long-term follow up studies are scant. METHODS: We conducted an observational study on patients who received a heart transplant at Saint Louis University Hospital between January 1, 1983 and December 31, 1988. Patients were followed up for 15 yr or until death whichever occurred first. In order to assess the effect of heart transplantation and cyclosporine exposure on long-term renal function we restricted the statistical analysis to patients who survived the first year post-transplantation. RESULTS: A total of 68 patients received orthotopic heart transplants at Saint Louis University Hospital between 1983 and 1988. Forty-eight (71%) patients survived for more than 1 yr. All patients were treated with cyclosporine based triple immunosuppressive regimen, with gradual cyclosporine dose reduction over time. The mean duration of follow-up was 8 yr. The estimated GFR at 5 and 10 yr post-transplant were significantly lower than estimated GFR at baseline and 1 yr post-transplant. There was no significant difference between estimated GFR at 15 yr and estimated GFR at baseline or 1 yr post-transplant. The cumulative incidence of chronic renal failure (GFR < or = 29 mL/min/1.73 m2) at 5, 10 and 15 yr was 4.2, 10.4 and 12.5%, respectively (p < 0.05). The cumulative incidence of severe chronic renal failure (GFR < or = 15 mL/min/1.73 m2) at 5, 10 and 15 yr was 2.1, 8.3 and 8.3%, respectively. The mortality rate was 8, 37, and 52% at 5, 10, and 15 yr, respectively. The 10 and 15 yr survivors had an estimated GFR at 1 yr post-transplant that was significantly higher than the non-survivors. Age, pre-transplantation estimated GFR, pre-transplantation diabetes and pre-transplantation hypertension are risk factors associated with > or = 10 mL/min/1.73 m2 decrement in estimated GFR. CONCLUSION: Heart transplant survivors beyond the first year post-transplant have a significant decrease in renal function and significant mortality observed over time. Age, pre-transplant GFR, pre-transplant diabetes and pre-transplant hypertension are important risk factors for decrement in renal function.     

Kaposi’s sarcoma following living donor kidney transplantation: review of 7,939 recipients

Introduction  Kaposi’s sarcoma (KS) is one of the most common tumors to occur in kidney recipients, especially in the Middle East countries. Limited data with adequate sample size exist about the development of KS in living kidney recipients. Methods  Therefore, we made a plan for a multicenter study, accounting for up to 36% (n = 7,939) of all kidney transplantation in Iran, to determine the incidence of KS after kidney transplantation between 1984 and 2007. Results  Fifty-five (0.69%) recipients who developed KS after kidney transplantation were retrospectively evaluated with a median follow-up of 24 (1–180) months. KS occurred more often in older age when compared to patients without KS (49 ± 12 vs. 38 ± 15 years, P = 0.000). KS was frequently found during the first 2 years after transplantation (72.7%). Skin involvement was universal. Furthermore, overall mortality rate was 18%, and it was higher in patients with visceral involvement compared to those with mucocutaneous lesions (P = 0.01). However, KS had no adverse affect on patient and graft survival rates compared to those without KS. Forty-four patients with limited mucocutaneous disease and four with visceral disease responded to withdrawal or reduction of immunosuppression with or without other treatment modalities. Renal function was preserved when immunosuppression was reduced instead of withdrawn in patients with and without visceral involvement (P = 0.001 and 0.008, respectively). Conclusion  The high incidence of KS in this large population studied, as compared to that reported in other transplant patient groups, suggests that genetic predisposition may play a pathogenetic role.     

Percutaneous Endoscopic Holmium Laser Lithotripsy for Management of Complicated Biliary Calculi

Background and Objectives:

Advances in endoscopic techniques have transformed the management of urolithiasis. We sought to evaluate the role of such urological interventions for the treatment of complex biliary calculi.

Methods:

We conducted a retrospective review of all patients (n=9) undergoing percutaneous holmium laser lithotripsy for complicated biliary calculi over a 4-year period (12/2003 to 12/2007). All previously failed standard techniques include ERCP with sphincterotomy (n=6), PTHC (n=7), or both of these. Access to the biliary system was obtained via an existing percutaneous transhepatic catheter or T-tube tracts. Endoscopic holmium laser lithotripsy was performed via a flexible cystoscope or ureteroscope. Stone clearance was confirmed intra- and postoperatively. A percutaneous transhepatic drain was left indwelling for follow-up imaging.

Results:

Mean patient age was 65.6 years (range, 38 to 92). Total stone burden ranged from 1.7 cm to 5 cm. All 9 patients had stones located in the CBD, with 2 patients also having additional stones within the hepatic ducts. All 9 patients (100%) were visually stone-free after one endoscopic procedure. No major perioperative complications occurred. Mean length of stay was 2.4 days. At a mean radiological follow-up of 5.4 months (range, 0.5 to 21), no stone recurrence was noted.

Conclusions:

Percutaneous endoscopic holmium laser lithotripsy is a minimally invasive alternative to open salvage surgery for complex biliary calculi refractory to standard approaches. This treatment is both safe and efficacious. Success depends on a multidisciplinary approach.