Faculty Bibliography

BACKGROUND: Deep brain stimulation of the subthalamic nucleus (STN) has demonstrated efficacy in improving motor disability in Parkinson's disease. The recently developed quantitative susceptibility mapping (QSM) technique, which can accurately map iron deposits in deep brain nuclei, promises precise targeting of the STN. OBJECTIVE: To demonstrate the use of QSM to target STN effectively by correlating with classical physiological-based targeting measures in a prospective study. METHODS: The precision and accuracy of direct targeting with QSM was examined in a total of 25 Parkinson's disease patients between 2013 and 2015 at our institution. QSM was utilized as the primary magnetic resonance imaging (MRI) method to perform direct STN targeting on a stereotactic planning station utilizing computed tomography/MR fusion. Intraoperative microelectrode recordings (MER) were obtained to confirm appropriate trajectory through the sensorimotor STN. RESULTS: Estimations of STN thickness between the MER and QSM methods appeared to be correlated. Mean STN thickness was 5.3 mm. Kinesthetic responsive cells were found in > 90% of electrode runs. The mean radial error (+/-SEM) was 0.54 +/- 0.1 mm. Satisfactory clinical response as determined by Unified Parkinson's Disease Rating Scale (UPDRS III) was seen at 12 mo after surgery. CONCLUSION: Direct targeting of the sensorimotor STN using QSM demonstrates MER correlation and can be safely used for deep brain stimulation lead placement with satisfactory clinical response. These results imply that targeting based on QSM signaling alone is sufficient to obtain reliable and reproducible outcomes in the absence of physiological recordings.

Biospecimen quality can vary depending on many pre- and post-collection variables. In this study, we consider a natural disaster as a post-collection variable that may have compromised the quality of frozen tissue specimens. To investigate this possible link, we compared the quality of nucleic acids, the level of antigenicity, and the preservation of histology from frozen specimens collected before and after the power outage caused by Hurricane Sandy. To analyze nucleic acid quality, we extracted both DNA and RNA and performed capillary electrophoresis to compare the quality and concentrations of the nucleic acids. To compare antigenicity, frozen sections were cut and immunostained for thyroid transcription factor 1 (TTF-1), a nuclear transcription protein commonly used as a diagnostic biomarker for multiple cancer types, including thyroid and lung cancers. Positive expression of TTF-1, as noted by homogenous nuclear staining, would demonstrate that the TTF-1 proteins could still bind antibodies and, therefore, that these proteins were not significantly degraded. Furthermore, representative frozen sections stained with hematoxylin and eosin were also assessed qualitatively by a trained pathologist to examine any possible histologic aberrations. Due to the similar quality of the tissue samples collected before and after the storm, Hurricane Sandy had no discernable effect on the quality of frozen specimens, and these specimens exposed to the natural disaster are still valuable research tools.

Objectives To assess the potential of infrared fiber-optic spectroscopy to evaluate the compositional properties of human tracheal cartilage. Study Design Laboratory-based study. Methods Twenty human cadaveric distal tracheas were harvested (age range 20-78 years; 6 females, 14 males) for compositional analysis. Histologic staining, Fourier transform infrared imaging spectroscopy data on collagen and proteoglycan (PG) content, and near-infrared (NIR) fiber-optic probe spectroscopic data that reflect protein and water content were evaluated. NIR fiber-optic probe data were also obtained from the proximal trachea in 4 human cadavers (age range 51-65 years; 2 females, 2 males) in situ for comparison to distal trachea spectral data. Results In the distal trachea cohort, the spectroscopic-determined ratio of PG/amide I, indicative of the relative amount of PG, was significantly higher in the tissues from the younger group compared to the older group (0.37 ± 0.08 vs 0.32 ± 0.05, P = .05). A principal component analysis of the NIR spectral data enabled separation of spectra based on tracheal location, likely due to differences in both protein and water content. The NIR-determined water content based on the 5200-cm^-1 peak was significantly higher in the distal trachea compared to the proximal trachea ( P < .001). Conclusions Establishment of normative compositional values and further elucidating differences between the segments of trachea will enable more directed research toward appropriate compositional end points in regenerative medicine for tracheal repair.

GOALS:To compare the adenoma detection rate (ADR) during colonoscopy in patients with melanosis coli against matched controls without melanosis. BACKGROUND:Melanosis coli is a colonoscopic finding in which the colon wall appears darkly pigmented, most often due to extended laxative use, and is considered benign. The pigmentation spares adenomas, which should therefore be more readily detectable in melanosis coli. STUDY:We identified all patients with melanosis on colonoscopy at our institution over a 5-year period. We matched each patient with 2 controls by age, gender, and endoscopist. We compared the prevalence of adenomas between groups, and used multivariable analysis, adjusting for procedure indication and bowel preparation quality, to determine the independent association of melanosis with adenoma detection. RESULTS:At least 1 adenoma was detected in 34.7% of melanosis patients and 26.5% of controls [odds ratio (OR)=1.52; 95% confidence interval (CI), 1.04-2.24; P=0.03]. On multivariable analysis, the presence of melanosis remained associated with increased adenoma detection (OR=1.56; 95% CI, 1.05-2.33; P=0.03). Melanosis patients were more likely to have an adenoma ≤5 mm (OR=1.62; 95% CI, 1.04-2.51; P=0.03), but not adenomas 6 to 9 mm or ≥10 mm. CONCLUSIONS:Melanosis coli is associated with a significant increase in ADR during colonoscopy compared with controls. The increased visibility of adenomas given their contrast with the pigmented background is a likely explanation. Future efforts to identify bowel preparation agents that can induce a similar effect could improve ADRs during colonoscopy.

OBJECTIVES/OBJECTIVE:The objectives of this study are to utilize the MAUDE data base to enhance our understanding of the complication profile for Occipital Nerve Stimulation, a therapy for which the current level of evidence is limited. Additionally, it is our objective to describe a systematic approach to processing the MAUDE data, which addresses its flaws and enhances its utility. METHODS:From the FDA website, we accessed adverse events reports from the MAUDE data base for devices used in Occipital Nerve Stimulation between June 30, 2007 and June 30, 2017. All reports were sorted into an overall classification for types of adverse events, types of patient complaints, and types of specific device-related complications. We then evaluated for the total number of adverse event reports that contained each of the patient complains and device-related complications. RESULTS:A total of 1233 adverse event records were obtained. Eight hundred twenty-two records were classified as surgically manageable post-operative complications, 121 as device malfunction, 29 as patient compliance issues, and 27 as intra-operative complications. Two hundred thirty-seven records were not classified. A total of 683 records contained patient complaints including 467 complaints of ineffective stimulation, 122 complaints of inappropriate or over-stimulation, 50 complaints of device-shock, and 44 complaints of IPG site pain. We found 581 post-operative device-related complications, which included 206 instances of lead migration, 157 reports of lead erosion, 155 infections, 46 lead-fractures, and 17 lead disconnections. CONCLUSION/CONCLUSIONS:The MAUDE data base is a useful tool to investigate device related complications and helps fill the current gap in ONS data. Reviewing the types and frequencies of complications reported over the years allows clinicians with less personal experience to have a more realistic expectation of complications and make informed decisions based on the patient's unique needs. Additionally, patient complaint data are useful in establishing more realistic expectations for patient outcomes.

Objective To analyze the patterns of care and survival for pT1-2N1M0 head and neck cancer based on receipt of surgery alone, surgery + postoperative radiotherapy (S + RT), or surgery + postoperative chemoradiotherapy (S + CRT). Study Design Retrospective analysis. Setting National Cancer Database. Subjects and Methods We queried the database for patients with stage pT1-2N1M0 squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx, or larynx between 2004 and 2012 who were treated with surgery with negative margins and no extracapsular extension. Logistic regression was used to assess predictors of receipt of postoperative treatment. Overall survival was assessed by the Kaplan-Meier method, and Cox regression analysis identified covariates that affected it. Results There were 1598 patients included in this study: 566 (35.4%) received surgery alone; 726 (45.4%), S + RT; and 306 (19.1%), S + CRT. The 5-year overall survival was 68.8%, 74.0%, and 87.8%, respectively ( P = .009 comparing S + RT and surgery alone, P < .001 for all other comparisons). On multivariable logistic regression, academic centers were associated with a decreased likelihood of S + RT (odds ratio = 0.71) and S + CRT (odds ratio = 0.66). Multivariable Cox regression demonstrated no difference in survival for S + RT over surgery alone (hazard ratio = 0.88, 95% CI = 0.70-1.09, P = .24); however, there was a survival benefit associated with S + CRT (hazard ratio = 0.57, 95% CI = 0.39-0.81, P = .002). Conclusion Nearly 65% of patients with pT1-2N1 head and neck cancer with negative margins and no extracapsular extension received S + RT or S + CRT. Improvement in survival was noted only for patients who received S + CRT.