About

Molly L. Alexander, MD, MSc, is an Assistant Professor (Clinical) in the Department of Pediatrics at the University of Utah. She specializes in Pediatric Emergency Medicine and is actively involved in clinical practice at Primary Children’s Hospital and other affiliated locations. Her educational background includes a B.S. in Biochemistry and Molecular Biology from Harding University, an M.D. from the University of Arkansas for Medical Sciences College of Medicine, and a residency in Pediatrics at Cincinnati Children’s Hospital Medical Center, University of Cincinnati College of Medicine. She also completed a fellowship in Global, Rural, and Underserved Child Health at the University of Utah Spencer Fox Eccles School of Medicine and Primary Children’s Hospital, along with graduate training in Public Health through the London School of Hygiene & Tropical Medicine. Her research includes contributions to pediatric transplantation, as evidenced by her publication on NTproBNP as a marker of rejection in pediatric heart transplant recipients.

Research topics

• Cardiology
• Internal medicine
• Medicine
• Surgery
• Radiology

Selected publications

• Temporal relationship between hematoma resolution and functional recovery after middle meningeal artery embolization for chronic subdural hematoma

  Journal of neurosurgery · 2026-05-01

  article

  OBJECTIVE: The objective was to evaluate the trajectories of hematoma resolution and functional improvement after middle meningeal artery embolization (MMAE) for chronic subdural hematoma (cSDH), model the temporal pattern of cSDH resolution, and identify factors associated with favorable outcomes. METHODS: This real-world multicenter retrospective study included cSDH patients treated with MMAE at 24 centers between 2019 and 2024. Hematoma thickness was measured at baseline and at follow-up intervals (1-4 weeks, 1-3 months, 3-6 months, 6-12 months, and > 12 months after embolization). Resolution patterns were modeled using exponential decay functions. Modified Rankin Scale (mRS) scores assessed functional outcomes. Good functional outcome was defined as mRS score ≤ 2. Resolution patterns were modeled using exponential decay functions to estimate time to 50% and 80% reduction. Patients were categorized as complete resolution (≥ 99%) or by quartile of the remaining distribution (substantial [73%-98%], moderate [53%-73%], partial [27%-53%], minimal [< 27%]). The primary outcome was good functional status (mRS score ≤ 2). RESULTS: The authors analyzed a total of 1781 patients with 2295 cSDHs who underwent MMAE. The mean ± SD age was 72.8 ± 12.4 years and 68.1% of patients were male. The initial mean hematoma thickness was 15.31 ± 6.53 mm, decreasing to 5.24 ± 5.91 mm at final follow-up (mean reduction 64.3% ± 42.1%). Resolution followed an exponential decay pattern, with an estimated time to 50% reduction of 1.8 months and to 80% reduction of 8.9 months. Complete resolution occurred in 1031 of 2224 patients (46.4%) with complete follow-up. The median (IQR) mRS score improved from 1 (0-3) at baseline to 0 (0-2) at > 12 months. Good functional outcomes were more common in patients with complete versus minimal resolution (68.9% vs 35.0%, p < 0.001). Achieving ≥ 73% resolution within 90 days was associated with better outcomes (good outcome in 76.9% of those with ≥ 73% resolution vs 67.3% in those without, p < 0.001). Neurological deterioration was the strongest predictor of lack of good outcome (23.7% in patients with neurological deterioration vs 82.4% without, p < 0.001). CONCLUSIONS: After MMAE for cSDH, reduction in hematoma thickness follows a predictable exponential decay pattern. Greater extent (≥ 80%) and faster timing (within 90 days) of resolution are valuable prognostic indicators. Functional outcomes improve progressively through 6-12 months after the procedure. The relationship between resolution extent and functional outcomes provides quantitative benchmarks for evaluating treatment response.

  PublisherDOI

• Cost-effectiveness of mechanical thrombectomy performed with the Monopoint reperfusion system compared to conventional contact aspiration and combined stentriever and aspiration

  Interventional Neuroradiology · 2025-11-17 · 1 citations

  articleOpen accessSenior authorCorresponding

  IntroductionUnderstanding of costs associated with different mechanical thrombectomy (MT) approaches lags behind procedural efficacy and safety considerations. This study evaluates cost-effectiveness of MT using Monopoint (Route 92 Medical, San Mateo, CA) as first-line approach compared to traditional contact aspiration (CA) and stentriever/aspiration (SA).MethodsRetrospective analysis of consecutively treated ICA terminus or M1 occlusion patients across four high-volume stroke centers was conducted, categorized into Monopoint, CA, or SA groups. Direct device costs and total costs were obtained from institutional databases. Statistical analyses included mixed-effects linear regression and multivariable analysis.ResultsAmong 148 patients undergoing MT (Monopoint: 74, CA: 32, SA: 42), device costs were lowest for the Monopoint group ($7836 ± 4570) vs. CA ($10,089 ± 6078, p < 0.001) and SA ($19,069 ± 4730, p < 0.001). Total costs followed a similar pattern (Monopoint: $27,089 ± 19,899, CA: $28,883 ± 14,161, p < 0.001, SA: $63,327 ± 72,440, p < 0.001). Monopoint demonstrated a higher final expanded Thrombolysis In Cerebral Infarction (eTICI) 2C/3 reperfusion rate (85.1% vs. 62.5% for CA, 71.4% for SA, p < 0.001) and fewer passes (1.8 vs. 2.0, p = 0.001). Technique crossover occurred less often with Monopoint compared to CA (6.8% vs. 34.4%, p < 0.001), and similar to SA (7.1%, p = 0.937). Post-procedural subarachnoid hemorrhage was more common with CA (16.7%) or SA (6.3%) compared to Monopoint (1.3%, p = 0.003).ConclusionFirst-line MT with Monopoint showed lower direct and total costs compared to CA and SA. Monopoint cost-effectiveness may be driven by fewer passes, decreased adjunctive device use, higher recanalization rates, fewer complications, and less post-MT hemorrhage, highlighting potential economic benefits of an optimized MT strategy.

  PublisherOA PDFDOI

• P-005 Cost effectiveness of mechanical thrombectomy performed with the monopoint reperfusion system compared to conventional contact aspiration and combined stentriever and aspiration

  2025-07-01

  articleSenior author
  PublisherDOI

• Shorter procedures and less radiation with monopoint aspiration compared to conventional aspiration or stentriever-assisted aspiration for mechanical thrombectomy

  Interventional Neuroradiology · 2025-10-17

  articleOpen accessSenior authorCorresponding

  Introduction Mechanical thrombectomy (MT) techniques affect procedure lengths and radiation exposure, with both reduced with contact aspiration (CA) compared to combination stentriever-assisted aspiration (SA). Monopoint MT has higher first pass effect (FPE) rates, less technical crossover, and recanalization with fewer passes. Monopoint MT may thus be associated with shorter procedural times and less radiation. Materials/Methods Anterior circulation large vessel MT cases across four centers were identified, assigning cases to Monopoint, CA, or SA groups based on the first-line technique employed, excluding cases that could not be assigned to one of these three groups. Clinical variables, technical details, times to first and final pass, fluoroscopy time, dose-area product (DAP), and radiation dose were recorded. Univariable and multivariable analyses were performed to compare procedural times and radiation data among treatment groups. Results Seventy-seven Monopoint, 32 CA, 42 SA cases were analyzed. Time to first pass was shortest with Monopoint ( p &lt; 0.001), as was time to final pass ( p &lt; 0.001). There was no significant difference in fluoroscopy time between Monopoint (17.7 min) and CA (17.6, p = 0.835); both were lower than SA (26.4, p &lt; 0.001). DAP was lowest for Monopoint (18,854 µGy*m 2 ) compared to CA (31,325) and SA (29,483, p &lt; 0.001). Radiation dose was lowest with Monopoint (884 mGy) compared to CA (1095) and SA (1994, p &lt; 0.001). Conclusion MT for anterior circulation large vessel occlusions had shorter procedural times and involved less radiation with Monopoint compared to CA and SA. Further investigation is warranted to assess other clinical and technical factors that affect procedure duration, DAP, and radiation dose.

  PublisherOA PDFDOI

• ECMO-facilitated rapid and deep hypothermia reduces brain injury on MRI following prolonged cardiac arrest in a translational swine model

  Resuscitation Plus · 2025-08-21

  articleOpen access

  Introduction: Neuroprotective interventions after cardiac arrest are essential but largely lack evidence of efficacy. Early therapeutic hypothermia (TH) is the only intervention that has shown promise in humans. However, despite a consistent signal for efficacy in animal models, conflicting clinical data hamper clinical acceptance. Two potential causes for the lack of translation from animal studies to humans are the time to achieve target temperature in humans and the inability to cool to deep hypothermic states due to the inherent detrimental cardiac effects accompanying deep hypothermia. Given the observed inconsistent impact of TH on human patients with cardiac arrest despite animal data, we developed a perfusion-controlled, translational swine model to quantify the effects of rapid deep TH on HIBI, quantifying severity using magnetic resonance imaging (MRI) with diffusion-weighted imaging (DWI) at a controlled time threshold. Methods: Ten swine underwent cardiac arrest with 20 min of "no-flow" state, followed by resuscitation and controlled reperfusion using extracorporeal membrane oxygenation (ECMO). Animals were randomized to either control (normal temperature reperfusion) or rapid hypothermic reperfusion (RHR) (29 °C through ECMO-facilitated cooling). All swine underwent brain MRI with Diffusion Weighted Imaging (DWI) before cardiac arrest and then 2 h after ECMO reperfusion. Whole-brain gray and white matter apparent diffusion coefficient (ADC) values were compared pre- and post-ECMO cannulation and arrest in all animals. Results: At 45 min post-reperfusion, the mean temperature for RHR animals was 30.4 °C (95 % CI 29.6-31.1 °C), while for control animals it was 35.7 °C (95 % CI 34.9-36.5 °C, p < 0.0001). Whole brain ADC in RHR swine increased by a mean of 1.36 ± 4.09 %, while in control swine it decreased by a mean of 4.36 ± 4.50 % (Median difference of -5.91, 95 %CI -12.13 to -0.15; P value = 0.047). Discussion: Swine with induced cardiac arrest who underwent rapid ECMO-mediated cooling post-arrest had less cerebral hypoxic cellular injury, as quantified by changes on MRI DWI, than controls. These findings support the protective effect on neurologic injury of a rapid and brief period of induced deep hypothermia after cardiac arrest. Compared to prior translational models, our use of ECMO has the advantage of an ability to control important factors such as no-flow ischemic time and variability in post-arrest cardiac output as well as to mitigate complications of cardiac dysrhythmias that tend to arise from deep hypothermia. This portends a greater promise for translational success of ECMO-facilitated rapid cooling and potentially other ECMO-mediated models of cardiac arrest than experienced by previous attempts.

  PublisherDOI

• Tenzingplasty for Cerebral Vasospasm Following Subarachnoid Hemorrhage and Meningitis: Multicenter Initial Experience

  medRxiv · 2025-05-14

  preprintOpen access1st authorCorresponding

  Introduction Cerebral vasospasm is a morbid complication of intracranial pathologies. Heterogeneity exists in treatment regimens, but management usually involves intensive medical therapy that may require augmentation with endovascular therapy, most commonly intra-arterial CCB infusion; angioplasty is historically reserved for refractory cases with a high risk for permanent neurological deficits. Given the high risk of iatrogenic complications with balloon angioplasty, alternative mechanical therapies have been explored. This series examines Dotter technique mechanical dilatation performed with Tenzing devices (Tenzingplasty). Methods IRB-approved retrospective analysis of prospectively maintained procedural databases and medical records was performed for patients undergoing Tenzingplasty at five high-volume cerebrovascular centers. Demographics, clinical features, and treatment details were recorded. Per-segment analysis was performed, including any treated arterial segment with narrowing ≥50%. The primary outcomes were improvement of treated vessel narrowing and improvement to less than 50% of baseline diameter. The primary safety outcome was any procedural complication. Secondary outcomes included absolute improvement in narrowing and need for repeat mechanical endovascular therapy to be performed on a previously targeted segment. Statistical analysis was performed with the Exact test for non-continuous variables and T-tests for continuous variables. Mixed effects linear and logistic regression analysis was then performed as appropriate for multivariable analysis. Results Fourteen patients were treated with Tenzingplasty for vasospasm; 12 (85.7%) had aSAH, and 2 (14.3%) had meningitis. Tenzing devices were passed through 82 arterial segments with narrowing ≥50%. All treated segments had improved narrowing, with 78 (95.1%) having residual narrowing &lt;50%. No procedural complications occurred. Mean (±SD) vessel narrowing improved from 80±13% to 34±14%, with absolute improvement of narrowing 46±17%. Three (3.7%) segments required repeat mechanical endovascular therapy. In univariable and multivariable analysis, no demographic, clinical, or treatment variables were associated with any Conclusion Tenzingplasty performed for cerebral vasospasm was safe and effective, with vessel narrowing improving in all treated segments. No procedural complications occurred in any treated segment. Low need for repeat mechanical endovascular therapy suggests a durable effect. Further investigation is warranted.

  PublisherOA PDFDOI

• Intracranial Dotter angioplasty using Tenzing (Tenzingplasty) for acute ischemic stroke with underlying intracranial atherosclerotic disease

  Journal of NeuroInterventional Surgery · 2025-06-27 · 2 citations

  article

  INTRODUCTION: Catheter-mediated (Dotter) angioplasty has been previously described for extracranial/peripheral arteries. Tenzing (Route 92 Medical, San Mateo, California, USA), a shelf-reducing delivery catheter, has an atraumatic tapered distal tip that progressively enlarges to maximal outer diameter of 1.2 mm (Tenzing 5), 1.6 mm (Tenzing 7), and 2.1 mm (Tenzing 8). OBJECTIVE: To report our initial experience treating acutely symptomatic intracranial atherosclerotic disease (ICAD) using Dotter angioplasty with Tenzing (Tenzingplasty). METHODS: After institutional review board approvals, we retrospectively reviewed clinical and procedural data of patients with underlying ICAD treated with off-label Tenzingplasty between 2022 and 2025, either as part of endovascular treatment for large vessel occlusion, or after medical therapy failure <96 hours from presentation. RESULTS: We identified 53 consecutive patients with symptomatic ICAD who underwent Tenzingplasty, median (IQR) age 63 (57-70) years, 29 (55%) male. ICAD locations were: M1 (24), M2 (9), internal carotid artery (3), vertebral V4 segment (7), basilar (8), vertebrobasilar junction (1), and A2 anterior cerebral artery (1). First pass aspiration thrombectomy for patients with an initial modified Thrombolysis in Cerebral Infarction score 0 (without crossing the ICAD lesion) was performed in 34/53 (64%). After median 1 (IQR 1-2) Tenzingplasty pass, median (IQR) stenosis improved from 100% (95-100) to 60% (42-76) post-Tenzingplasty (P<0.0001). Subsequent balloon angioplasty or stenting was performed in 4% and 21%, respectively. Successful final reperfusion (expanded Thrombolysis in Cerebral Infarction 2b-3) was achieved in 81%, with one Tenzingplasty-related complication (a non-flow limiting dissection), and no perforations. In follow up, 25/44 (57%) had a 90-day modified Rankin Scale score of 0-2. CONCLUSION: Tenzingplasty may be a feasible and safe rescue therapy for improving luminal caliber, flow restoration, and/or lesion preparation for stenting in acutely symptomatic ICAD.

  PublisherDOI

• O-010 Multicenter experience of monopoint reperfusion system in acute anterior circulation large vessel occlusion thrombectomy

  2025-07-01

  article
  PublisherDOI

• Tenzing Assisted Delivery of Aspiration (TADA) technique for thrombectomy of medium vessel occlusions using the Freeclimb 54 catheter: multicenter experience

  Journal of NeuroInterventional Surgery · 2025-01-23 · 11 citations

  articleOpen access

  BACKGROUND: Medium vessel occlusions (MeVOs) account for 25-40% of acute ischemic stroke. The Tenzing 5 (Route 92 Medical, San Mateo, California, USA) and FreeClimb 54 (Route 92 Medical, San Mateo, California, USA) catheter is a novel delivery-aspiration catheter combination designed to facilitate aspiration thrombectomy (AT) of MeVOs. We report our clinical experience using the Tenzing assisted delivery of aspiration (TADA) technique with FreeClimb 54 for first-line AT of MeVO. METHODS: We retrospectively reviewed consecutive patients who underwent MeVO first-line AT using TADA with FreeClimb 54 at nine institutions in the USA and one in New Zealand. RESULTS: 94 MeVOs (65 primary, 29 secondary) were treated in 92 patients: median age 71 (IQR 58-81) years; 49/92 (53%) women. FreeClimb 54 was successfully delivered by Tenzing 5 to all 94/94 MeVOs: 26 proximal M2; 44 distal M2; 5 M3; 6 A2; 4 A3; and 8 P2. Median target vessel diameter on DSA was 1.7 (IQR 1.4-1.8) mm. A leading microwire was used to advance Tenzing in 84% of cases. A stent retriever was used for additional thrombectomy passes in 6/94 (6%) patients. For a primary MeVO, final modified expanded Thrombolysis in Cerebral Infarction (meTICI) 2B-3 reperfusion was achieved in 63/65 (97%) patients, after a median of 1 (IQR 1-2) pass, with a first pass effect (FPE, meTICI 2C-3) in 43/65 (66%). Secondary MeVO FPE (eTICI 2C-3) was achieved in 20/29 (69%) patients. Tenzing 5-FreeClimb 54 related complications occurred in 2/94 (2%) patients: one perforation with asymptomatic subarachnoid hemorrhage and one embolus to new territory. CONCLUSIONS: MeVO first-line AT using the TADA technique with Tenzing 5 and FreeClimb 54 had a high FPE with a low complication rate.

  PublisherOA PDFDOI

• Multicenter experience of the Monopoint reperfusion system in acute large vessel occlusion stroke thrombectomy

  Journal of NeuroInterventional Surgery · 2025-07-08 · 4 citations

  article

  BACKGROUND: The Monopoint reperfusion system (Monopoint; Route 92 Medical, San Mateo, California, USA) is a large bore (0.088 or 0.070 inch inner diameter) aspiration thrombectomy platform designed to minimize ledge effect and improve neurovascular navigation and embolectomy. We aimed to describe a multicenter, real world experience of the safety and performance of the Monopoint system in first line aspiration thrombectomy for large vessel occlusions (LVOs), outside of the recently completed SUMMIT MAX (A Randomized, Controlled Trial to Evaluate the Safety and Effectiveness of the Route 92 Medical Reperfusion System) clinical trial. METHODS: Adults with acute anterior circulation LVO stroke between January 2019 and December 2024 consecutively treated with first line aspiration thrombectomy using the Monopoint at 10 centers were retrospectively reviewed. The primary outcome was first pass effect (FPE, modified Thrombolysis in Cerebral Infarction (mTICI) 2C/3 on first pass) and modified FPE (mFPE, mTICI 2B/2C/3 on first pass). The primary safety outcome was the rate of intraprocedural complications attributed to the Monopoint system. RESULTS: In 193 included patients, median age was 67 years (IQR 67-78), and 46.6% (90/193) were women. Successful delivery of the aspiration catheter to the clot site occurred in 96.2% (185/193) of patients. FPE was achieved in 57.5% (111/193) and mFPE was achieved in 68.4% (132/193) of patients. Of 10 (5.2%) total complications, most were vasospasm treated with intra-arterial verapamil (8/193, 4.1%); major complications included one dissection (1/193, 0.5%) and one perforation (1/193, 0.5%). CONCLUSION: This multicenter study of the Monopoint reperfusion system for LVO thrombectomy outside of the SUMMIT MAX trial demonstrated a high FPE rate and a low rate of major complications.

  PublisherDOI

Frequent coauthors

• Daniel L. Cooke

  University of California, San Francisco

  75 shared

• Steven W. Hetts

  University of California, San Francisco

  71 shared

• Van V. Halbach

  University of California, San Francisco

  62 shared

• Christopher F. Dowd

  Cystic Fibrosis Foundation

  61 shared

• Matthew R. Amans

  University of California System

  52 shared

• Randall T. Higashida

  47 shared

• Vijay M. Ravindra

  Rady Children's Hospital-San Diego

  46 shared

• Adam de Havenon

  Yale New Haven Hospital

  46 shared