Browsing by Subject "Prosthesis Implantation"

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    An Analysis of Public Interest in Elective Neurosurgical Procedures During the COVID-19 Pandemic Through Online Search Engine Trends.
    (World neurosurgery, 2021-04) Feng, Austin Y; Garcia, Cesar A; Jin, Michael C; Ho, Allen L; Li, Gordon; Grant, Gerald; Ratliff, John; Skirboll, Stephen L

    Objective

    In the wake of the COVID-19 pandemic, the Centers for Medicare & Medicaid Services (CMS) has recommended the temporary cessation of all elective surgeries. The effects on patients' interest of elective neurosurgical procedures are currently unexplored.

    Methods

    Using Google Trends, search terms of 7 different neurosurgical procedure categories (trauma, spine, tumor, movement disorder, epilepsy, endovascular, and miscellaneous) were assessed in terms of relative search volume (RSV) between January 2015 and September 2020. Analyses of search terms were performed for over the short term (February 18, 2020, to April 18, 2020), intermediate term (January 1, 2020, to May 31, 2020), and long term (January 2015 to September 2020). State-level interest during phase I reopening (April 28, 2020, to May 31, 2020) was also evaluated.

    Results

    In the short term, RSVs of 4 categories (epilepsy, movement disorder, spine, and tumor) were significantly lower in the post-CMS announcement period. In the intermediate term, RSVs of 5 categories (miscellaneous, epilepsy, movement disorder, spine, and tumor) were significantly lower in the post-CMS announcement period. In the long term, RSVs of nearly all categories (endovascular, epilepsy, miscellaneous, movement disorder, spine, and tumor) were significantly lower in the post-CMS announcement period. Only the movement disorder procedure category had significantly higher RSV in states that reopened early.

    Conclusions

    With the recommendation for cessation of elective surgeries, patient interests in overall elective neurosurgical procedures have dropped significantly. With gradual reopening, there has been a resurgence in some procedure types. Google Trends has proven to be a useful tracker of patient interest and may be used by neurosurgical departments to facilitate outreach strategies.
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    Characterization of porous, dexamethasone-releasing polyurethane coatings for glucose sensors.
    (Acta Biomaterialia, 2014-11) Vallejo-Heligon, Suzana G; Klitzman, Bruce; Reichert, William M
    Commercially available implantable needle-type glucose sensors for diabetes management are robust analytically but can be unreliable clinically primarily due to tissue-sensor interactions. Here, we present the physical, drug release and bioactivity characterization of tubular, porous dexamethasone (Dex)-releasing polyurethane coatings designed to attenuate local inflammation at the tissue-sensor interface. Porous polyurethane coatings were produced by the salt-leaching/gas-foaming method. Scanning electron microscopy and micro-computed tomography (micro-CT) showed controlled porosity and coating thickness. In vitro drug release from coatings monitored over 2 weeks presented an initial fast release followed by a slower release. Total release from coatings was highly dependent on initial drug loading amount. Functional in vitro testing of glucose sensors deployed with porous coatings against glucose standards demonstrated that highly porous coatings minimally affected signal strength and response rate. Bioactivity of the released drug was determined by monitoring Dex-mediated, dose-dependent apoptosis of human peripheral blood derived monocytes in culture. Acute animal studies were used to determine the appropriate Dex payload for the implanted porous coatings. Pilot short-term animal studies showed that Dex released from porous coatings implanted in rat subcutis attenuated the initial inflammatory response to sensor implantation. These results suggest that deploying sensors with the porous, Dex-releasing coatings is a promising strategy to improve glucose sensor performance.
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    Interstitial engraftment of adipose-derived stem cells into an acellular dermal matrix results in improved inward angiogenesis and tissue incorporation.
    (J Biomed Mater Res A, 2013-10) Komatsu, Issei; Yang, Jun; Zhang, Ying; Levin, L Scott; Erdmann, D; Klitzman, Bruce; Hollenbeck, Scott T
    Acellular dermal matrices (ADM) are commonly used in reconstructive procedures and rely on host cell invasion to become incorporated into host tissues. We investigated different approaches to adipose-derived stem cells (ASCs) engraftment into ADM to enhance this process. Lewis rat adipose-derived stem cells were isolated and grafted (3.0 × 10(5) cells) to porcine ADM disks (1.5 mm thick × 6 mm diameter) using either passive onlay or interstitial injection seeding techniques. Following incubation, seeding efficiency and seeded cell viability were measured in vitro. In addition, Eighteen Lewis rats underwent subcutaneous placement of ADM disk either as control or seeded with PKH67 labeled ASCs. ADM disks were seeded with ASCs using either onlay or injection techniques. On day 7 and or 14, ADM disks were harvested and analyzed for host cell infiltration. Onlay and injection techniques resulted in unique seeding patterns; however cell seeding efficiency and cell viability were similar. In-vivo studies showed significantly increased host cell infiltration towards the ASCs foci following injection seeding in comparison to control group (p < 0.05). Moreover, regional endothelial cell invasion was significantly greater in ASCs injected grafts in comparison to onlay seeding (p < 0.05). ADM can successfully be engrafted with ASCs. Interstitial engraftment of ASCs into ADM via injection enhances regional infiltration of host cells and angiogenesis, whereas onlay seeding showed relatively broad and superficial cell infiltration. These findings may be applied to improve the incorporation of avascular engineered constructs.
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    Off-label closure during CLOSURE study.
    (J Invasive Cardiol, 2012-11) Stackhouse, Kathryn A; Goel, Sachin S; Qureshi, Athar M; Prieto, Lourdes; Kapadia, Samir; Tuzcu, E Murat; Krasuski, Richard A
    BACKGROUND: The role of percutaneous closure of patent foramen ovale (PFO) in patients with cryptogenic stroke or transient ischemic attack remains controversial. Registry data have suggested considerable benefit of closure over medical therapy, but the prospective, randomized CLOSURE I trial found no benefit for device closure. METHODS: We compared patients enrolled into CLOSURE I to off-label closures performed during the study recruitment period at a single large institution and prospectively enrolled into an institutional registry of PFO closure. We also compared CLOSURE I patients at our institution to the reported characteristics of the entire study to ensure generalizability. RESULTS: Between 11/3/2003 and 4/16/2007, there were 100 off-label closures and 33 patients randomized into CLOSURE I. Compared with off-label closure, patients in CLOSURE I were younger (41.6 ± 10.1 years vs 50.0 ± 14.0 years; P<.001) and had fewer cardiovascular risks including hypertension (12% vs 36%; P=.009), hyperlipidemia (24% vs 53%; P=.008), and coronary disease (3% vs 44%; P<.001). Degree of right-to-left shunting was considerably higher in off-label closures (28%, 14%, and 58% vs 45%, 30%, and 25% for mild, moderate, and severe, respectively; P=.026). CONCLUSION: Off-label closures outnumbered patient recruitment into CLOSURE 3:1 at our institution during study recruitment. Certain demographic differences were expected (age over 60 was an exclusion for CLOSURE I), but vascular risks were considerably greater in the off-label group and may be important mechanistically. Large shunts were considerably more common in off-label patients, suggesting that higher-risk patients may have been preferentially closed off-label. These results suggest that the results of CLOSURE I may not apply to all patients with initial cryptogenic stroke.