An Outcomes Comparison Between Autologous and Alloplastic Cranioplasty in the Pediatric Population.

BACKGROUND: The use of alloplastic material in cranial reconstruction has been well described in the adult population, especially when a paucity of autologous tissue exists. In children it is unknown how long-term growth, however, may be affected by the implantation of nonexpansible alloplastic material. Therefore, the authors sought to compare the outcomes of pediatric patients undergoing alloplastic versus autologous cranial reconstruction. METHODS: To assess the safety and long-term outcomes of alloplastic cranioplasty in children, an institutional review board-approved, retrospective, single institution review of pediatric patients undergoing cranioplasty was performed from 2000 to 2014. The age at surgery, cause of the cranial defect, defect size, time since initial surgery to reconstruction, implant type, and complications were assessed. Postreconstruction imaging was reviewed if available. RESULTS: A reconstructive cranioplasty was performed in 41 pediatric patients (ages 1-19 years, average 7.35 years). Thirty patients underwent alloplastic reconstruction (age 4.37 ±â€Š5.57 years), and 11 underwent autologous reconstruction (age 2.00 ±â€Š3.74 years). The size of the cranial defects was 144.01 ±â€Š393.04 cm for autologous and 405.31 ±â€Š572.96 cm for alloplastic reconstructions. Follow-up for all patients was an average of 2.33 ±â€Š2.76 years (0.1-9 years). No patients in either group showed evidence of elevated intracranial pressure after cranioplasty. In long-term follow-up, none of the implants were exposed or lost because of infection. Computed tomography and physical examination demonstrated that there was no skull growth restriction in either group. CONCLUSIONS: Our data show that alloplastic cranioplasty in the pediatric population is a safe alternative, when autologous cranial bone is not available.

Botulinum Toxin Use in Pediatric Plastic Surgery.

Botulinum toxin has increasingly become a prevalent treatment option for a wide range of conditions, many of which have their roots in plastic surgery and have been well studied. In adults, chronic headache, hyperhidrosis, and facial muscular hypertrophy have been effectively treated with botulinum toxin, and emerging studies have begun looking at its efficacy in children, as well. Successful treatment of spasticity and muscular contraction has allowed for the creation of safety profiles and dosage guidelines for botulinum toxin usage in children. The expanded indications for its use have since flourished in all arenas of pediatric care, including plastic surgery. Recent studies have described the use of botulinum toxin as an adjunct to the treatment of congenital torticollis and cleft lip. This review discusses the various applications of botulinum toxin for pediatric patients in the field of plastic surgery.

Low-affinity nerve growth factor receptor p75NTR immunoreactivity in the myocardium with sympathetic hyperinnervation.

INTRODUCTION: We previously demonstrated the relationship between sympathetic nerve density in myocardium and the occurrences of ventricular arrhythmia. Nerve growth factor (NGF) regulates myocardial sympathetic innervation. However, it is unclear whether the NGF high-affinity receptor tyrosine kinase A (TrkA) and the NGF low-affinity receptor p75NTR are altered in the state of sympathetic hyperinnervation in the heart. The aim of this study was to determine the density and location of TrkA and p75NTR in canine ventricles with sympathetic hyperinnervation. METHODS AND RESULTS: Myocardial sympathetic hyperinnervation was induced by local infusion of NGF into myocardium or left stellate ganglia, or chronic subthreshold electric stimulation to the left stellate ganglia. The results showed that TrkA immunoreactivity was absent in the myocardium. Low-affinity receptor p75NTR immunoreactivity was present in axons, Schwann cells, and interstitial cells of sympathetic nerves, as well as in interstitial cells of the myocardium. The density of p75NTR immunolabeled myocardial interstitial cells at the NGF infusion site was lower than that at the site remote from NGF infusion, yet the sympathetic nerve density was higher at the infusion site than the remote area. The density of p75NTR also was lower in the myocardium with high sympathetic nerve density, induced by NGF infusion or chronic electric stimulation of the left stellate ganglia, compared to control groups. CONCLUSION: The data indicate that p75NTR may be the main NGF receptor in the myocardium, and p75NTR immunopositive interstitial cells may have a role in regulating sympathetic nerve growth in canine heart.

Nerve sprouting induced by radiofrequency catheter ablation in dogs.

OBJECTIVES: The purpose of this study was to test the hypothesis that radiofrequency (RF) catheter ablation results in cardiac nerve sprouting. BACKGROUND: Nerve sprouting plays a role in cardiac arrhythmogenesis. Whether or not nerve sprouting occurs after RF catheter ablation is unclear. METHODS: We performed RF catheter ablation in the right atrium (RA) and right ventricle (RV) in 10 dogs, which then were sacrificed in 2 hours (acute group, n = 5) or 1 month (chronic group, n = 5). Seven normal dogs were used as control. Immunohistochemical staining for growth-associated protein 43 (GAP-43) was performed to measure growing (sprouting) nerves. RESULTS: A significant increase of GAP-43 immunoreactive nerve fiber density was observed at the RA ablation sites in 2 hours (4,410 +/- 1,379 microm(2)/mm(2)) and in 1 month (2,948 +/- 666 microm(2)/mm(2)) after ablation compared to controls (1,377 +/- 471 microm(2)/mm(2), P = .0001). At remote sites (>2 cm away from ablation sites) of RA, RF ablation also resulted in robust nerve sprouting in both the acute group (5,846 +/- 3241 microm(2)/mm(2)) and the chronic group (6,030 +/- 2226 microm(2)/mm(2)). RF ablation in the RV did not increase nerve density at the ablation sites, but nerve density was increased at remote sites in 2 hours (1,345 +/- 451 microm(2)/mm(2), P = .0136) that was reduced down to the normal control level (722 +/- 337 microm(2)/mm(2)) in 1 month. CONCLUSIONS: Nerve sprouting occurred within 2 hours after RF ablation in both the RA and RV and persisted for at least 1 month in the RA but not the RV. The increased GAP-43(+) nerve densities developed at both the ablation and the remote sites.