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Open Access Publications from the University of California

Scholarly Works (6 results)

  • Article
  • Peer Reviewed
UC San Diego Previously Published Works (2018)
Background Today, patients can access a myriad of information sources regarding plastic surgery procedures prior to meeting with a surgeon. Despite their widespread use, the role of these sources in a patient's decision-making remains undefined. We hypothesized that the physician remains the key information source for patients making surgical decisions in plastic surgery, but that other sources may deliver important insights and prove helpful to varying degrees. We also explored motivations for this outside information search and any differences in perceived value among patients. Methods We administered a survey regarding various information sources to our breast reconstruction, reduction, and abdominoplasty patients. Responses were compared between surgery groups and demographic groups. Ordinal logistic regression analysis was used to determine the impact of patient characteristics on helpfulness rank of different sources. Results Survey results were obtained from 58 patients, of whom 10 (17.2%) had abdominoplasty, 35 (60.3%) breast reconstruction, and 13 (22.4%) breast reduction. The most popular information sources prior to the first surgical appointment were Internet searches (56.9%) and family/friends/other patients (39.7%). After the initial appointment, the most useful sources were plastic surgeons (84.5%), and the Internet (36.2%). Most patients (73.5%) still sought outside information after their appointment. On a Likert-type scale of helpfulness, plastic surgeons ranked 4.28/5, followed by the web-based patient education platform, 3.73 and the Internet, 3.6. A total of 63% of participants listed plastic surgeons as their single most important source of information. In ordinal logistic regression analysis, non-white race was significantly associated with higher rank of surgeon helpfulness (p < 0.05). Relative to low-income patients, income $50-100k (p < 0.05) and $100k+ (p < 0.05) were associated with lower rank of surgeon helpfulness. Conclusions Most patients seek outside information prior to visiting with a surgeon from the Internet, social media, or family and friends. Patients consider plastic surgeons their most valuable information source overall, though still in need of supplementation for varying reasons. Additionally, certain demographic differences affect patient perception of information sources, and this is an important factor for surgeons to consider as they approach educating patients.
    Cover page: Evaluation of Information Sources in Plastic Surgery Decision-making
    • Article
    • Peer Reviewed
    UC San Diego Previously Published Works (2018)
    The physiologic processes underlying MRI contrast enhancement in glioblastoma patients remain poorly understood. MRIs of 148 glioblastoma subjects from The Cancer Imaging Archive were segmented using Iterative Probabilistic Voxel Labeling (IPVL). Three aspects of contrast enhancement (CE) were parametrized: the mean intensity of all CE voxels (CEi), the intensity heterogeneity in CE (CEh), and volumetric ratio of CE to necrosis (CEr). Associations between these parameters and patterns of gene expression were analyzed using DAVID functional enrichment analysis. Glioma CpG island methylator phenotype (G-CIMP) glioblastomas were poorly enhancing. Otherwise, no differences in CE parameters were found between proneural, neural, mesenchymal, and classical glioblastomas. High CEi was associated with expression of genes that mediate inflammatory responses. High CEh was associated with increased expression of genes that regulate remodeling of extracellular matrix (ECM) and endothelial permeability. High CEr was associated with increased expression of genes that mediate cellular response to stressful metabolic states, including hypoxia and starvation. Our results indicate that CE in glioblastoma is associated with distinct biological processes involved in inflammatory response and tissue hypoxia. Integrative analysis of these CE parameters may yield meaningful information pertaining to the biologic state of glioblastomas and guide future therapeutic paradigms.
      Cover page: Molecular physiology of contrast enhancement in glioblastomas: An analysis of The Cancer Imaging Archive (TCIA)
      • Multimedia
      • Peer Reviewed
      Symposium 2023 (2023)

      Efficacy of Radiation Reduction Protocols for Diagnostic Angiography and Basic Interventions in Endovascular Neurosurgery

       

      Arvin R. Wali MD, MAS, Michael G. Brandel MD, MAS, Sarath Pathuri BS, Brian R. Hirshman MD, PhD, Javier Bravo MD, Jeffrey Steinberg MD, Scott Olson MD, J. Scott Pannell MD, David R. Santiago-Dieppa MD, Alexander A. Khalessi MD, MBA

       

      Background

       

      Safe radiation practices and “As Low As Reasonably Achievable” (ALARA) principles are critical to mitigate unnecessary radiation to patients, providers, and staff. Radiation has stochastic and deterministic effects that have deleterious effects on health and lead to complications such as cancer, leukemia, and cataracts. As the indications for neuroendovascular procedures continue to grow, Neurointerventionalists must have a strong command over practices that reduce unnecessary radiation dose. We applied a quality improvement protocol to manipulate default pulse rate and frame rate settings on our Siemens Artis Q biplane to determine if radiation safety practices could allow for quality diagnostic angiograms and the performance of safe and effective interventions.

       

      Methods

      We implemented a radiation reduction protocol January 1st 2022 in which the default pulse rate and frame rate in our Siemens Artis Q biplane was reduced from 15 pulses per second (p/s) to 7.5 p/s and 7.5 frames per second (f/s) to 4.0 f/s. We performed a retrospective review of prospectively acquired data to calculate the impact of our radiation reduction protocol on total radiation dose, radiation per angiographic run, total radiation exposure, and exposure per run.  We examined 29 consecutive diagnostic angiograms (16 prior to intervention, and 13 post intervention) and 16 consecutive, unilateral middle meningeal artery embolizations (MMAEs) (8 prior to intervention, and 8 post intervention). A blinded neuroradiologist reviewed the angiograms to determine if there was sufficient diagnostic information in the angiograms before and after intervention. Univariable and multivariable log-linear regression were performed to account for patient body mass index (BMI), number of angiographic runs, and number of vessels catheterized. Statistical analysis was performed using STATA MP Version 17.0 (Stata Corp LP, College Station, Texas). Significance was defined as p < 0.05.

       

      Results

      For the diagnostic angiograms, univariable analysis revealed that radiation dose (550.5 vs. 353.3 mGy, p=0.005), radiation dose per angiographic run (34.6 vs. 21.9, p<0.001), total radiation exposure (7050.7 vs. 4490.7 mGym2, p=0.013), and exposure per run (429.8 vs. 281.9, p<0.001) were all significantly decreased after the protocol. On multivariable log-linear regression adjusting for BMI, number of runs, vessels catheterized, and fluoroscopy time, the protocol was associated with a 45.4% decrease in the total radiation dose (p<0.001) and a 53.3% decrease in radiation dose per run (p<0.001). For the MMAEs, univariable analysis revealed that radiation dose (660.9 vs. 407.5 mGy, p=0.002), radiation dose per angiographic run (40.3 vs. 25.7, p<0.001), total radiation exposure (8825.8 vs. 5510.4 mGym2, p=0.002), and exposure per run (537.9 vs. 353.5, p=0.002) were all significantly decreased after the protocol. Both groups were well balanced in terms of clinical characteristics (Table 1 and 2). No changes in image quality were identified by an expert interventional neuroradiologist. Fluoroscopy and procedural time did not differ between MMAE groups (20min vs 21min p=0.65).

       

      Conclusions

      Radiation reduction protocols are highly effective for neuroendovascular interventions. We strongly encourage all interventionalists to be cognizant of pulse rate and frame rate when performing routine interventions to avoid unnecessary radiation towards patients, providers, and health care staff.

       

      • 1 supplemental ZIP
      • Article
      • Peer Reviewed
      UC San Diego Previously Published Works (2023)
      Embolization of the middle meningeal artery (MMA) is a safe and effective adjunct in the treatment of chronic subdural hematoma. While prior authors describe the use of coils to assist embolization by preventing reflux through eloquent collaterals, we de- scribe the use of coils to further open the MMA, allowing the administration of greater amounts of embolisate for a more robust embolization. The objective of this study was to demonstrate that helical coils can safely open the MMA following the administration of polyvinyl alcohol (PVA) particles. This allows for more embolisate to be administered into the MMA for more effective treatment. A retrospective review was conducted at our institution including intraoperative images and postoperative clinical and radiographic follow up. Failure rates using MMA embolization with PVA and helical coil augmentation were compared to failure rates in the literature of MMA embolization with PVA or ethylene vinyl-alcohol copolymer alone. A total of 8 cases were reviewed in which this technique was implemented. There were no immediate complications after treatment. All patients that underwent helical coil embolization following the administration of PVA had increased amount of embolisate delivered into the MMA. All patients at follow up had resolution of the subdural hematoma on outpatient imaging. Helical coil embolization allows for more embolisate administration into the MMA and provides a technical advantage for patients that fail traditional techniques of embolization. Case series are taking place to further test this hypothesis and identify the ideal patient population that may gain maximal yield from this novel technique.
        Cover page: Helical coils augment embolization of the middle meningeal artery for treatment of chronic subdural hematoma: A technical note
        • Article
        • Peer Reviewed
        UC San Diego Previously Published Works (2022)
        Anatomic knowledge of the internal auditory canal (IAC) and surrounding structures is a prerequisite for performing skull base approaches to the IAC. We herein perform a morphometric analysis of the IAC and surgically relevant aspects of the posterior petrous bone during pediatric maturation, a region well-studied in adults but not children. Measurements of IAC length (IAC-L), porus (IAC-D) and midpoint (IAC-DM) diameter, and distance from the porus to the common crus (CC; P-CC) and posterior petrosal surface (PPS) to the posterior semicircular canal (PSC; PPS-PSC) were made on thin-cut axial CT scans from 60 patients (grouped by ages 0-3, 4-7, 8-11 12-15, 16-18, and > 18 years). IAC-L increased 27.5% from 8.7 ± 1.1 at age 0-3 to 11.1 ± 1.1 mm at adulthood (p = 0.001), with the majority of growth occurring by ages 8-11. IAC-D (p = 0.52) and IAC-DM (p = 0.167) did not significantly change from ages 0-3 to adult. P-CC increased 31.1% from 7.7 ± 1.5 at age 0-3 to 10.1 ± 1.5 mm at adulthood (p = 0.019). PPS-PSC increased 160% from 1.5 ± 0.7 at age 0-3 to 3.9 ± 1.2 mm at adulthood (p < 0.001). The majority of growth in P-CC and PPS-PSC occurred by ages 12-15. Knowledge of these patterns may facilitate safe exposure of the IAC in children.
          Cover page: Maturation of the internal auditory canal and posterior petrous bone with relevance to lateral and posterolateral skull base approaches.
          • Article
          • Peer Reviewed
          UC San Diego Previously Published Works (2018)
          Mass effect has demonstrated prognostic significance for glioblastoma, but is poorly quantified. Here we define and characterize a novel neuroimaging parameter, lateral ventricle displacement (LVd), which quantifies mass effect in glioblastoma patients. LVd is defined as the magnitude of displacement from the center of mass of the lateral ventricle volume in glioblastoma patients relative to that a normal reference brain. Pre-operative MR images from 214 glioblastoma patients from The Cancer Imaging Archive (TCIA) were segmented using iterative probabilistic voxel labeling (IPVL). LVd, contrast enhancing volumes (CEV) and FLAIR hyper-intensity volumes (FHV) were determined. Associations with patient survival and tumor genomics were investigated using data from The Cancer Genome Atlas (TCGA). Glioblastoma patients had significantly higher LVd relative to patients without brain tumors. The variance of LVd was not explained by tumor volume, as defined by CEV or FLAIR. LVd was robustly associated with glioblastoma survival in Cox models which accounted for both age and Karnofsky's Performance Scale (KPS) (p = 0.006). Glioblastomas with higher LVd demonstrated increased expression of genes associated with tumor proliferation and decreased expression of genes associated with tumor invasion. Our results suggest LVd is a quantitative measure of glioblastoma mass effect and a prognostic imaging biomarker.
            Cover page: Quantification of glioblastoma mass effect by lateral ventricle displacement.
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