Medical student interested in spine surgery and big data analytics.
Education & Certifications
Bachelor of Science, University of Southern California, Neuroscience (2016)
Medical student interested in spine surgery and big data analytics.
Skull fractures are common after blunt pediatric head trauma. CSF leaks are a rare but serious complication of skull fractures; however, little evidence exists on the risk of developing a CSF leak following skull fracture in the pediatric population. In this epidemiological study, the authors investigated the risk factors of CSF leaks and their impact on pediatric skull fracture outcomes.The authors queried the MarketScan database (2007-2015), identifying pediatric patients (age < 18 years) with a diagnosis of skull fracture and CSF leak. Skull fractures were disaggregated by location (base, vault, facial) and severity (open, closed, multiple, concomitant cerebral or vascular injury). Descriptive statistics and hypothesis testing were used to compare baseline characteristics, complications, quality metrics, and costs.The authors identified 13,861 pediatric patients admitted with a skull fracture, of whom 1.46% (n = 202) developed a CSF leak. Among patients with a skull fracture and a CSF leak, 118 (58.4%) presented with otorrhea and 84 (41.6%) presented with rhinorrhea. Patients who developed CSF leaks were older (10.4 years vs 8.7 years, p < 0.0001) and more commonly had skull base (n = 183) and multiple (n = 22) skull fractures (p < 0.05). These patients also more frequently underwent a neurosurgical intervention (24.8% vs 9.6%, p < 0.0001). Compared with the non-CSF leak population, patients with a CSF leak had longer average hospitalizations (9.6 days vs 3.7 days, p < 0.0001) and higher rates of neurological deficits (5.0% vs 0.7%, p < 0.0001; OR 7.0; 95% CI 3.6-13.6), meningitis (5.5% vs 0.3%, p < 0.0001; OR 22.4; 95% CI 11.2-44.9), nonroutine discharge (6.9% vs 2.5%, p < 0.0001; OR 2.9; 95% CI 1.7-5.0), and readmission (24.7% vs 8.5%, p < 0.0001; OR 3.4; 95% CI 2.5-4.7). Total costs at 90 days for patients with a CSF leak averaged $81,206, compared with $32,831 for patients without a CSF leak (p < 0.0001).The authors found that CSF leaks occurred in 1.46% of pediatric patients with skull fractures and that skull fractures were associated with significantly increased rates of neurosurgical intervention and risks of meningitis, hospital readmission, and neurological deficits at 90 days. Pediatric patients with skull fractures also experienced longer average hospitalizations and greater healthcare costs at presentation and at 90 days.
View details for DOI 10.3171/2019.8.FOCUS19543
View details for Web of Science ID 000493985900010
View details for PubMedID 31675705
BACKGROUND: Although the incidence of spinal fusions has increased significantly in the United States over the last quarter century, national trends of anterior lumbar interbody fusion (ALIF) utilization are not known.PURPOSE: The objective of this study was to characterize trends, clinical characteristics, risk factors associated with, and outcomes of ALIF in the United States.STUDY DESIGN: This was an epidemiological study using national administrative data from the MarketScan database.METHODS: Using a large administrative database, we identified adults who underwent ALIF in the United States from 2007 to 2014. The incidence of ALIF was studied longitudinally over time and across geographic regions in the United States. Data related to postoperative complications, length of stay, readmission, and cost were collected.RESULTS: We identified 49,945 patients that underwent ALIF in the United States between 2007 and 2014. The total number of ALIF procedures increased from 3650 in 2007 to 6151 in 2014, accounting for an average increase of 24.07% annually. The Southern United States performed the highest number of ALIFs. The most common conditions treated were degenerative disc disease and spondylolisthesis. Over one third of patients (34.6%) underwent multilevel fusion. The most common complications were iron deficiency anemia, urinary tract infections, and pulmonary complications. Hospital and physician pay increased significantly during the study period.CONCLUSIONS: For the first time in our knowledge, we identified national trends in ALIF utilization, outcomes, and cost using a large administrative database. Our study reaffirms prior work that has demonstrated low rates of complications, mortality, and readmission following ALIF.LEVEL OF EVIDENCE: Level III.
View details for DOI 10.1097/BSD.0000000000000904
View details for PubMedID 31609798
BACKGROUND: Spinal arteriovenous malformations (AVM) are an abnormal interconnection of vasculature in the spine than can lead to significant neurological deficit if left untreated.OBJECTIVE: The objective of this study was to characterize how spinal AVM patients initially presented, what treatment options were utilized, and their overall outcomes on a national scale.METHODS: The MarketScan database was queried to identify adult patients diagnosed with a spinal AVM from 2007 - 2015. Trends in management, postoperative complication rates, and costs were determined.RESULTS: 976 patients were identified with having a diagnosis of a spinal AVM. Patients were more commonly treated with an open incision than an embolization (40.1% vs 15.4%). The overall complication rate was 33.61%. Spinal AVM admissions have been stable over the past decade and mean cost of hospitalization has risen from of $48,700 in 2007 to $71,292 in 2015. Patients who underwent open surgery had a higher complication rate than those treated with embolization (31.15% vs 18.25%, p < 0.005); however, this may be strongly influenced by complexity of spinal AVM pathology and not treatment modality.CONCLUSIONS: Costs of spinal AVM management continue to rise, even when treatment modalities have reduced length of stay significantly. Open surgery may lead to more postoperative complications and a higher length of stay than endovascular approaches. Further studies should look to identify the efficacy of endovascular approaches for spinal cord AVMs, particularly in complex spinal AVM traditionally treated with open surgery and to isolate factors leading to the elevated hospitalization costs.LEVEL OF EVIDENCE: III.
View details for DOI 10.1016/j.wneu.2019.08.010
View details for PubMedID 31404690
STUDY DESIGN: Technical Report with two illustrative cases.OBJECTIVE: Grade II spondylolisthesis remains a complex surgical pathology for which there is no consensus regarding optimal surgical strategies. Surgical strategies vary regarding extent of reduction, utilization of instrumentation/interbody support, and anterior versus posterior approaches with or without decompression. The objective of this study is to provide the first report on the efficacy of robotic spinal surgery systems in supporting the treatment of grade II spondylolisthesis.METHODS: Utilizing two illustrative cases, we provide a technical report of how a robotic spinal surgery platform can be utilized to treatment grade II spondylolisthesis with a novel instrumentation strategy.RESULTS: We describe how utilization of the "Reverse Bohlman" technique to achieve a large anterior fusion construct spanning the pathologic level and buttressed by the adjacent level above, coupled with a novel, high fidelity posterior fixation scheme with transdiscal S1-L5 and S2Ai screws placed in a minimally invasive fashion with robot guidance allows for the best chance of fusion in situ.CONCLUSIONS: The "Reverse Bohlman" technique coupled with transdiscal S1-L5 and S2Ai screw fixation accomplishes the surgical goals of creating a solid fusion construct, avoiding neurologic injury with aggressive reduction, and halting the progression of anterolisthesis. Utilization of robot guidance allows for efficient placement of these difficult screw trajectories in a minimally invasive fashion.
View details for DOI 10.1016/j.wneu.2019.07.229
View details for PubMedID 31398524
A cell culture platform that enables ex vivo tissue growth from patients or patient-derived xenograft (PDX) models and assesses sensitivity to approved therapies (e.g. Temozolomide, TMZ) in a clinically relevant timeframe would be very useful in translational research and personalized medicine. Here, we present a novel three-dimensional (3D) ECM hydrogel system, VersaGel, for assaying ex vivo growth and therapeutic response with standard image microscopy. Specifically, multicellular spheroids deriving from either five glioblastoma (GBM) patients or a renal cell carcinoma (RCC) PDX model were incorporated into VersaGel and treated with TMZ and several other therapies, guided by the most recent advances in GBM treatment. RCC ex vivo tissue displayed invasive phenotypes in conditioned media. For the GBM patient tumor testing, all 5 clinical responses were predicted by the results of our 3D-TMZ assay. In contrast, the MTT assay found no response to TMZ regardless of the clinical outcome. Finally, one patient was tested with repurposed drugs currently being administered in GBM clinical trials. Interestingly, IC50's were lower than cmax for crizotinib and chloroquine, but higher for sorafenib. In conclusion, a novel hydrogel platform, VersaGel, enables ex vivo tumor growth of patient and PDX tissue and offers insight into patient response to clinically relevant therapies.
View details for PubMedID 30755456
BACKGROUND: The morbidity and mortality associated with opioid and benzodiazepine co-prescription is a pressing national concern. Little is known about patterns of opioid and benzodiazepine use in patients with acute low back pain or lower extremity pain.OBJECTIVE: To characterize patterns of opioid and benzodiazepine prescribing among opioid-naive, newly diagnosed low back pain (LBP) or lower extremity pain (LEP) patients and to investigate the relationship between benzodiazepine prescribing and long-term opioid use.DESIGN/SETTING: We performed a retrospective analysis of a commercial database containing claims for more than 75 million enrollees in the USA.PARTICIPANTS: Participants were adult patients newly diagnosed with LBP or LEP between 2008 and 2015 who did not have a red flag diagnosis, had not received an opioid prescription in the 6months prior to diagnosis, and had 12months of continuous enrollment after diagnosis.MAIN OUTCOMES AND MEASURES: Among patients receiving at least one opioid prescription within 12months of diagnosis, we defined discrete patterns of benzodiazepine prescribing-continued use, new use, stopped use, and never use. We tested the association of these prescription patterns with long-term opioid use, defined as six or more fills within 12months.RESULTS: We identified 2,497,653 opioid-naive patients with newly diagnosed LBP or LEP. Between 2008 and 2015, 31.9% and 11.5% of these patients received opioid and benzodiazepine prescriptions, respectively, within 12months of diagnosis. Rates of opioid prescription decreased from 34.8% in 2008 to 27.0% in 2015 (P<0.001); however, prescribing of benzodiazepines only decreased from 11.6% in 2008 to 10.8% in 2015. Patients with continued or new benzodiazepine use consistently used more opioids than patients who never used or stopped using benzodiazepines during the study period (one-way ANOVA, P<0.001). For patients with continued and new benzodiazepine use, the odds ratio of long-term opioid use compared with those never prescribed a benzodiazepine was 2.99 (95% CI, 2.89-3.08) and 2.68 (95% CI, 2.62-2.75), respectively.LIMITATIONS: This study used administrative claims analyses, which rely on accuracy and completeness of diagnostic, procedural, and prescription codes.CONCLUSION: Overall opioid prescribing for low back pain or lower extremity pain decreased substantially during the study period, indicating a shift in management within the medical community. Rates of benzodiazepine prescribing, however, remained at approximately 11%. Concurrent prescriptions of benzodiazepines and opioids after LBP or LEP diagnosis were associated with increased risk of long-term opioid use.
View details for DOI 10.1007/s11606-019-05549-8
View details for PubMedID 31720966
Low back pain (LBP) with or without lower extremity pain (LEP) is one of the most common reasons for seeking medical care. Previous studies investigating costs in this population targeted patients receiving surgery. Little is known about health care utilization among patients who do not undergo surgery.To assess use of health care resources for LBP and LEP management and analyze associated costs.This cohort study used a retrospective analysis of a commercial database containing inpatient and outpatient data for more than 75 million individuals. Participants were US adults who were newly diagnosed with LBP or LEP between 2008 and 2015, did not have a red-flag diagnosis, and were opiate naive prior to diagnosis. Dates of analysis were October 6, 2018, to March 7, 2019.Newly diagnosed LBP or LEP.The primary outcome was total cost of care within the first 6 and 12 months following diagnosis, stratified by whether patients received spinal surgery. An assessment was performed to determine whether patients who did not undergo surgery received care in accordance with proposed guidelines for conservative LBP and LEP management. Costs resulting from use of different health care services were estimated.A total of 2?498?013 adult patients with a new LBP or LEP diagnosis (median [interquartile range] age, 47 [36-58] years; 1?373?076 [55.0%] female) were identified. More than half (55.7%) received no intervention. Only 1.2% of patients received surgery, but they accounted for 29.3% of total 12-month costs ($784 million). Total costs of care among the 98.8% of patients who did not receive surgery were $1.8 billion. Patients who did not undergo surgery frequently received care that was inconsistent with clinical guidelines for LBP and LEP: 32.3% of these patients received imaging within 30 days of diagnosis and 35.3% received imaging without a trial of physical therapy.The findings suggest that surgery is rare among patients with newly diagnosed LBP and LEP but remains a significant driver of spending. Early imaging in patients who do not undergo surgery was also a major driver of increased health care expenditures. Avoidable costs among patients with typically self-limited conditions result in considerable economic burden to the US health care system.
View details for PubMedID 31074820
Idiopathic intracranial hypertension results in increased intracranial pressure leading to headache and visual loss. This disease frequently requires surgical intervention through lumboperitoneal (LP) or ventriculoperitoneal (VP) shunting.To compare postoperative outcomes between LP and VP shunts, including failure and complication rates.A retrospective analysis was conducted using a national administrative database (MarketScan) to identify idiopathic intracranial hypertension (IIH) patients who underwent LP or VP shunting from 2007 to 2014. Multivariate logistic and Cox regressions were performed to compare rates of shunt failure and time to shunt failure between LP and VP shunts while controlling for demographics and comorbidities.The analytic cohort included 1082 IIH patients, 347 of whom underwent LP shunt placement at index hospitalization and 735 of whom underwent VP shunt placement. Rates of shunt failure were similar among patients with LP and VP shunt (34.6% vs 31.7%; P = .382). Among patients who experienced shunt failure, the mean number of shunt failures was 2.1 ± 1.6 and was similar between LP and VP cohorts. Ninety-day readmission rates, complication rates, and costs did not differ significantly between LP and VP shunts. Patients who experienced more than two shunt failures tended to have an earlier time to first shunt failure (hazard ratio 1.41; 95% confidence interval 1.08-1.85; P = .013).These findings suggest that LP and VP shunts may have comparable rates of shunt failure and complication. Regardless of shunt type, earlier time to first shunt failure may be associated with multiple shunt failures.
View details for PubMedID 30937428
Gangliogliomas (GG) are rare tumors of the nervous system. Patient characteristics and clinical outcomes of low and high-grade GG have been difficult to elucidate in the adult population. This study aims to further elaborate on GG treatment and overall survival utilizing a larger cohort than previously published. The USA National Cancer Database was utilized to evaluate adult (age 18years and older) patients diagnosed with GG between 2004 and 2006. Descriptive statistics and Kaplan-Meier overall survival estimates were provided. A total of 198 adult GG patients were diagnosed between 2004 and 2006. Of these, 181 (91.4%) were low-grade and 17 (8.6%) high-grade GG. Overall, the median age was 36years; approximately 50% of patients were female, and 86.5% Caucasian. Most patients (59%) had near/gross total resection. Radiation and chemotherapy were prescribed in 18 (9.1%) and 11 (5.7%) patients, respectively. Radiation (64.7% versus 3.9%, p<.0001) and chemotherapy (47.1% versus 1.7%, p<.0001) were more frequently given to patients with high-grade tumors than low-grade. The median overall survival of high-grade GG was 44.4months (95% confidence interval [CI]: 10.5-92.5) while the corresponding estimate for low-grade tumors was not reached. Older age (hazard ratio [HR] 1.72, 95% CI: 1.26-2.34) and high tumor grade (HR 3.91, 95% CI: 1.43-10.8) were found to be associated with poor survival. Adult GG have a temporal lobe predilection and overall gross total resection rate of 59%. Older patients with high-grade tumors had an increased hazard of mortality. High-grade GG were significantly more likely to be treated with radiation therapy and chemotherapy.
View details for DOI 10.1016/j.jocn.2015.12.028
View details for Web of Science ID 000379888500011
View details for PubMedID 27083133
Ependymoma is a rare primary brain or spinal cord tumor that arises from the ependyma, a tissue of the central nervous system. This study analyzed a large cohort of adult supratentorial and posterior fossa ependymoma tumors in order to elucidate factors associated with overall survival. We utilized the USA National Cancer Database to study adult World Health Organization grade II/III supratentorial and posterior fossa ependymoma patients treated between 1998 and 2011. Overall survival was estimated by the Kaplan-Meier method and factors associated with survival were determined using a multivariate Cox proportional hazards model. Among 1318 patients, 1055 (80.0%) had grade II and 263 (20.0%) anaplastic tumors located in the posterior fossa (64.3%) and supratentorial region (35.7%). Overall average age was 44.3years, 48.0% of patients were female, 86.5% were Caucasian, and 36.8% underwent near/gross total surgical resection. Radiotherapy was given to 662 patients (50.8%) and 75 (5.9%) received chemotherapy. Older age at diagnosis (hazard ratio [HR] 1.51, p<0.0001), high tumor grade (HR 1.82, p=0.005), and large tumor size (HR 1.66, p=0.008) were associated with poor survival. Females compared to males (HR 0.67, p=0.03) and patients with posterior fossa tumors versus supratentorial (HR 0.64, p=0.04) had a survival advantage. Our study showed that older patients, with supratentorial tumors, and high histological grade had an increased risk of mortality. A survival benefit was captured in females and patients with posterior fossa tumors. Adjuvant radiotherapy and chemotherapy did not confer a survival benefit among all patients, even after stratification by tumor grade or anatomical location.
View details for DOI 10.1016/j.jocn.2015.11.014
View details for Web of Science ID 000376714500006
View details for PubMedID 26810473
OBJECT Head trauma is the leading cause of death in abused children, particularly prior to the age of 2 years. An awareness of factors associated with this condition as well as with a higher risk of mortality is important to improve outcomes and prevent the occurrence of these events. The objective of this study was to evaluate outcomes and factors associated with poor outcomes in infants with diagnosed abusive head trauma (AHT). Patient characteristics, socioeconomic factors, and secondary conditions such as retinal bleeding, contusion, and fractures were considered. METHODS Data were obtained from the Healthcare Cost and Utilization Project of the Agency for Healthcare Research and Quality. From the Kids' Inpatient Database (KID) sample, the authors identified infants no older than 23 months who had been diagnosed with AHT in 2000, 2003, 2006, and 2009. All statistical analyses were conducted in SAS 9.2. Descriptive statistics were provided, and multivariate logistic regression models were applied to evaluate factors associated with mortality and nonroutine discharge. RESULTS A total of 5195 infants were analyzed in this study. Most infants (85.5%) had ages ranging between 0 and 11 months and were male (61.6%). Overall mortality was 10.8%, with a rate of 9.8% in the 0- to 11-month-old cohort and 16.5% in the 12- to 23-month-olds (p = 0.0003). The overall nonroutine discharge rate of 25.6% increased significantly from 23.3% to 39.0% with increasing age (0-11 vs 12-23 months of age, p < 0.0001). Assuming a multivariate model that adjusted for multiple confounders, the authors found that older infants (12-23 vs 0-11 months, OR 1.81, 95% CI 1.18-2.77) with a secondary diagnosis of retinal bleeding (OR 2.85, 95% CI 2.02-4.00) or shaken baby syndrome (OR 2.09, 95% CI 1.48-2.94) had an increased risk of mortality; these factors were similarly associated with an increased odds of a nonroutine discharge. A higher income ($30,001-$35,000 vs $1-$24,999) was associated with a reduction in the odds of mortality (OR 0.46, 95% CI 0.29-0.72). In the subset of cases (1695 [32.6%]) that specified the perpetrator involved in infant injury, the authors found that the father, stepfather, or boyfriend was most frequently reported (67.4%). A trend for a higher AHT incidence was documented in the early ages (peak at 2 months) compared with older ages. CONCLUSIONS Despite the higher incidence of AHT among infants during the earlier months of life, higher mortality was documented in the 12- to 23-month-olds. Retinal bleeding and shaken baby syndrome were secondary diagnoses associated with higher mortality and nonroutine discharge. Males (67.4%) were overwhelmingly documented as the perpetrators involved in the injury of these infants.
View details for DOI 10.3171/2015.3.PEDS14544
View details for Web of Science ID 000363439700009
View details for PubMedID 26230462