Ying Meng and Nir Lipsman
Karim Mithani, Ying Meng, David Pinilla, Nova Thani, Kayee Tung, Richard Leung and Howard J. Ginsberg
A 52-year-old man with a 10-year history of treatment-resistant asthma presented with repeated exacerbations over the course of 10 months. His symptoms were not responsive to salbutamol or inhaled corticosteroid agents, and he developed avascular necrosis of his left hip as a result of prolonged steroid therapy. Physical examination and radiography revealed signs consistent with diffuse idiopathic skeletal hyperostosis (DISH), including a C7–T1 osteophyte causing severe tracheal compression. The patient underwent C6–T1 anterior discectomy and fusion, and the compressive osteophyte was removed, which completely resolved his “asthma.” Postoperative pulmonary function tests showed normalization of his FEV1/FVC ratio, and there was no airway reactivity on methacholine challenge. DISH is a systemic, noninflammatory condition characterized by ossification of spinal entheses, and it can present with respiratory disturbances due to airway compression by anterior cervical osteophytes. The authors present, to the best of their knowledge, the first documented case of asthma as a presentation of DISH.
Lauren Conova, Jennifer Vernengo, Ying Jin, B. Timothy Himes, Birgit Neuhuber, Itzhak Fischer, Anthony Lowman, Jennifer Vernengo, Ying Jin, B. Timothy Himes, Birgit Neuhuber, Itzhak Fischer and Anthony Lowman
The authors investigated the feasibility of using injectable hydrogels, based on poly(N-isopropylacrylamide) (PNIPAAm), lightly cross-linked with polyethylene glycol (PEG) or methylcellulose (MC), to serve as injectable scaffolds for local delivery of neurotrophins and cellular transplants into the injured spinal cord. The primary aims of this work were to assess the biocompatibility of the scaffolds by evaluating graft cell survival and the host tissue immune response. The scaffolds were also evaluated for their ability to promote axonal growth through the action of released brain-derived neurotrophic factor (BDNF).
The in vivo performance of PNIPAAm-g-PEG and PNIPAAm-g-MC was evaluated using a rodent model of spinal cord injury (SCI). The hydrogels were injected as viscous liquids into the injury site and formed space-filling hydrogels. The host immune response and biocompatibility of the scaffolds were evaluated at 2 weeks by histological and fluorescent immunohistochemical analysis. Commercially available matrices were used as a control and examined for comparison.
Experiments showed that the scaffolds did not contribute to an injury-related inflammatory response. PNIPAAm-g-PEG was also shown to be an effective vehicle for delivery of cellular transplants and supported graft survival. Additionally, PNIPAAm-g-PEG and PNIPAAm-g-MC are permissive to axonal growth and can serve as injectable scaffolds for local delivery of BDNF.
Based on the results, the authors suggest that these copolymers are feasible injectable scaffolds for cell grafting into the injured spinal cord and for delivery of therapeutic factors.
Ying Meng, Mathew R. Voisin, Suganth Suppiah, Zamir Merali, Ali Moghaddamjou, Naif M. Alotaibi, Arbelle Manicat-Emo, Shelly Weiss, Cristina Go, Blathnaid McCoy, Elizabeth J. Donner and James T. Rutka
Intracranial electroencephalography (iEEG) monitoring is an important method of identifying the seizure focus in patients with medically refractory epilepsy. While previous studies have demonstrated low rates of surgical complications, reported rates of surgical site infection (SSI) are highly variable. To date, no studies have specifically evaluated the patient or operative risk factors contributing to SSI. The goals of this study were to examine the rate of SSI after iEEG monitoring for epilepsy workup in pediatric patients and to determine the variables that might contribute to the development of SSI.
A retrospective analysis of hospital charts at the Hospital for Sick Children was performed for all patients who had undergone iEEG monitoring between 2000 and 2016. Univariate and multivariate analyses were performed to look for statistically significant variables in relation to SSI.
Among 199 patients eligible for analysis, 8 (4.0%) developed SSIs within a period ranging from 21 to 51 days postoperatively. Univariate analysis yielded 4 factors related to SSI: number of people present in the operating room on electrode insertion (p = 0.02), length of insertion surgery (p = 0.04), previous operation at the same surgical site (p = 0.04), and number of depth electrodes inserted (p = 0.01). Multivariate analysis revealed that both the number of people present during the implant operation (OR 0.08, 95% CI 0.01–0.70) and the number of depth electrodes inserted (OR 3.52, 95% CI 1.44–8.59) independently contributed to SSI.
This is the largest case series and the first comprehensive review of both patient and operative risk factors in the development of SSI from iEEG monitoring in a pediatric population. The authors’ institution had a lower rate of infection than those in most other studies, which could be explained by their protocol of administering intravenous antibiotics perioperatively and post–implant removal antibiotics for 14 days. The authors found a correlation between SSI and the number of people present during the implant operation, as well as the number of depth electrodes; both may contribute to breaks in sterility.