43 results on '"Paydarfar JA"'
Search Results
2. Submental Island Pedicled Flap vs Radial Forearm Free Flap for Oral Reconstruction: Comparison of Outcomes.
- Author
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Paydarfar JA and Patel UA
- Published
- 2011
- Full Text
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3. Complications in head and neck surgery: a meta-analysis of postlaryngectomy pharyngocutaneous fistula.
- Author
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Paydarfar JA and Birkmeyer NJ
- Published
- 2006
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4. An Imaging-Compatible Oral Retractor System for Transoral Robotic Surgery.
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Shi Y, Wu X, Paydarfar JA, and Halter RJ
- Subjects
- Humans, Mouth surgery, Mouth diagnostic imaging, Printing, Three-Dimensional, Robotic Surgical Procedures instrumentation, Robotic Surgical Procedures methods, Magnetic Resonance Imaging instrumentation, Tomography, X-Ray Computed
- Abstract
This study aimed to develop and validate a Computed Tomography (CT)/Magnetic Resonance Imaging (MRI)-compatible polymer oral retractor system to enable intraoperative image guidance for transoral robotic surgery (TORS). The retractor was designed based on standard-of-care metallic retractors and 3D (three-dimensional) printed with carbon fiber composite and nylon. The system was comprehensively evaluated in bench-top and cadaveric experiments in terms of its ability to enable intraoperative CT/MR images during TORS, functionality including surgical exposure and working volume, usability, compatibility with da Vinci surgical systems, feasibility for disinfection or sterilization, and robustness over an extended period of time. The polymer retractor system enabled the acquisition of high-resolution and artifact-free intraoperative CT/MR images during TORS. With an inter-incisive distance of 42.55 mm and a working volume of 200.09 cm
3 , it provided surgical exposure comparable to standard-of-care metallic retractors. The system proved intuitive and compatible with da Vinci S, Xi, and Single Port systems, enabling successful mock surgical tasks performed by surgeons and residents. The retractor components could be effectively disinfected or sterilized for clinical use without significant compromise in material strength, with STERRAD considered the optimal method. Throughout a 2 h mock procedure, the retractor system showed minimal displacements (<1.5 mm) due to surrounding tissue deformation, with insignificant device deformation. The 3D-printed polymer retractor system successfully enabled artifact-free intraoperative CT/MR imaging in TORS for the first time and demonstrated feasibility for clinical use. This breakthrough opens the door to surgical navigation with intraoperative image guidance in TORS, offering the potential to significantly improve surgical outcomes and patients' quality of life., (© 2024. The Author(s) under exclusive licence to Biomedical Engineering Society.)- Published
- 2024
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5. The art of specimen orientation: Two-dimensional maps for oropharynx squamous cell carcinoma.
- Author
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Divakar P, Kim SS, Kerr DA, Pettus JR, and Paydarfar JA
- Subjects
- Humans, Squamous Cell Carcinoma of Head and Neck, Oropharyngeal Neoplasms surgery, Oropharyngeal Neoplasms pathology, Carcinoma, Squamous Cell surgery, Carcinoma, Squamous Cell pathology, Head and Neck Neoplasms
- Abstract
The goal of surgical treatment for oropharynx squamous cell carcinoma (SCCa) is resection to negative margins. Current methods of orienting resection specimens often do not give a comprehensive view, especially in oropharynx SCCa where specimens can lack anatomic landmarks. We created standardized two-dimensional maps of oropharynx anatomy drawn to scale to improve communication between surgeons and pathologists. Notes regarding surgery including anatomic landmarks, areas of concern, additional margins, and relevant clinical information were added to the map. The maps guided pathology work-up, and the pathologist could communicate details back to the surgeon on how the specimen was sectioned or locations of microscopic foci to direct future treatment and clinical monitoring. The use of two-dimensional maps for oropharynx SCCa specimens offers a standardized solution to address the challenges of anatomic orientation. These maps summarized key pathological information, preserved clinical details from the specimens, and guided multidisciplinary conferences when planning adjuvant treatment., (© 2023 Wiley Periodicals LLC.)
- Published
- 2024
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6. Oncologic Safety of Close Margins in Patients With Low- to Intermediate-Grade Major Salivary Gland Carcinoma.
- Author
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Sajisevi M, Nguyen K, Callas P, Holcomb AJ, Vural E, Davis KP, Thomas CM, Plonowska-Hirschfeld KA, Stein JS, Eskander A, Kakarala K, Enepekides DJ, Hier MP, Ryan WR, Asarkar AA, Aulet R, Bell RK, Blasco MA, Bowmaster VB, Burruss CP, Chung J, Chan K, Chang BA, Coffey CS, Cognetti DM, Cooper DJ, Cordero J, Donovan J, Du YJ, Dundar Y, Dedivitis RA, Edwards HA, Erovic BM, Feinberg PA, Garvey EA, Goldstein DP, Goodman JF, Goulart RN, Goyal N, Grasl S, Giurintano JP, Gupta N, Habib AM, Hackman TG, Hara JH, Henson C, Hinni ML, Hua N, Johnson-Obaseki S, Juloori A, Kalman NS, Kejner AE, Khaja SF, Ku JA, Lambert A, Luu BK, Magliocca KR, Dos Santos LRM, Michael C, Miles BA, de Melo GM, Moore MG, Morand GB, Moura K, Mukdad L, Noroozi H, Patel R, Paydarfar JA, Sadeghi N, Savaria FN, Schmitt NC, Shapiro J, Shaver TB, Stoeckli SJ, St John M, Stokes WA, Sulibhavi A, Tasoulas J, Vendra V, Vinh DB, Virgen CG, Wooten C, Woody NM, and Young GD
- Subjects
- Humans, Male, Female, Infant, Adult, Middle Aged, Aged, Retrospective Studies, Cohort Studies, Margins of Excision, Carcinoma surgery, Salivary Gland Neoplasms radiotherapy, Salivary Gland Neoplasms surgery, Salivary Gland Neoplasms pathology
- Abstract
Importance: Postoperative radiation therapy for close surgical margins in low- to intermediate-grade salivary carcinomas lacks multi-institutional supportive evidence., Objective: To evaluate the oncologic outcomes for low- and intermediate-grade salivary carcinomas with close and positive margins., Design, Setting, and Participants: The American Head and Neck Society Salivary Gland Section conducted a retrospective cohort study from 2010 to 2019 at 41 centers. Margins were classified as R0 (negative), R1 (microscopically positive), or R2 (macroscopically positive). R0 margins were subclassified into clear (>1 mm) or close (≤1 mm). Data analysis was performed from June to October 2023., Main Outcomes and Measures: Main outcomes were risk factors for local recurrence., Results: A total of 865 patients (median [IQR] age at surgery, 56 [43-66] years; 553 female individuals [64%] and 312 male individuals [36%]) were included. Of these, 801 (93%) had parotid carcinoma and 64 (7%) had submandibular gland carcinoma, and 748 (86%) had low-grade tumors and 117 (14%) had intermediate-grade tumors, with the following surgical margins: R0 in 673 (78%), R1 in 168 (19%), and R2 in 24 (3%). Close margins were found in 395 of 499 patients with R0 margins (79%), for whom margin distances were measured. A total of 305 patients (35%) underwent postoperative radiation therapy. Of all 865 patients, 35 (4%) had local recurrence with a median (IQR) follow-up of 35.3 (13.9-59.1) months. In patients with close margins as the sole risk factor for recurrence, the local recurrence rates were similar between those who underwent postoperative radiation therapy (0 of 46) or observation (4 of 165 [2%]). Patients with clear margins (n = 104) had no recurrences. The local recurrence rate in patients with R1 or R2 margins was better in those irradiated (2 of 128 [2%]) compared to observed (13 of 64 [20%]) (hazard ratio [HR], 0.05; 95% CI, 0.01-0.24). Multivariable analysis for local recurrence found the following independent factors: age at diagnosis (HR for a 10-year increase in age, 1.33; 95% CI, 1.06-1.67), R1 vs R0 (HR, 5.21; 95% CI, 2.58-10.54), lymphovascular invasion (HR, 4.47; 95% CI, 1.43-13.99), and postoperative radiation therapy (HR, 0.10; 95% CI, 0.04-0.29). The 3-year local recurrence-free survivals for the study population were 96% vs 97% in the close margin group., Conclusions and Relevance: In this cohort study of patients with low- and intermediate-grade major salivary gland carcinoma, postoperative radiation therapy for positive margins was associated with decreased risk of local recurrence. In isolation from other risk factors for local recurrence, select patients with close surgical margins (≤1 mm) may safely be considered for observation.
- Published
- 2024
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7. Estimating tongue deformation during laryngoscopy using a hybrid FEM-multibody model and intraoperative tracking - a cadaver study.
- Author
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Wu X, Sánchez CA, Lloyd JE, Borgard H, Fels S, Paydarfar JA, and Halter RJ
- Abstract
Throat tumour margin control remains difficult due to the tight, enclosed space of the oral and throat regions and the tissue deformation resulting from placement of retractors and scopes during surgery. Intraoperative imaging can help with better localization but is hindered by non-image-compatible surgical instruments, cost, and unavailability. We propose a novel method of using instrument tracking and FEM-multibody modelling to simulate soft tissue deformation in the intraoperative setting, without requiring intraoperative imaging, to improve surgical guidance accuracy. We report our first empirical study, based on four trials of a cadaveric head specimen with full neck anatomy, yields a mean TLE of 10.8 ± 5.5 mm, demonstrating methodological feasibility.
- Published
- 2024
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8. Predictors of gastrostomy tube placement in patients with head and neck cancer undergoing resection and flap-based reconstruction: systematic review and meta-analysis.
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Stewart T, Copeland-Halperin LR, Demsas F, Divakar P, Shank N, Blunt H, J Levy J, Nigriny JF, and Paydarfar JA
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- Humans, Gastrostomy, Risk Factors, Retrospective Studies, Postoperative Complications, Plastic Surgery Procedures, Free Tissue Flaps, Head and Neck Neoplasms surgery
- Abstract
Background: Nutritional status may be impaired in patients with head and neck cancer undergoing surgical treatment, often necessitating gastrostomy tube (G-tube) placement. Identifying which patients will require a G-tube remains a challenge. This study identifies predictors of G-tube requirement in patients undergoing tumor resection and reconstruction with pedicled or free flaps., Methods: Systematic review of the PubMed, Cochrane, and Scopus databases was performed of English language articles, discussing risk factors of perioperative G-tube placement among patients >18 years. Data on patient, tumor, and treatment factors, as well as need for G-tube, were collected. Univariable meta-analysis was conducted to identify predictors for G-tube placement., Results: Eleven studies (1,112 patients) met inclusion criteria. Overall pooled prevalence of postoperative G-tube placement was 25%. Patients with advanced cancer stage IV/recurrence were more likely to require a G-tube (OR 2.81 [CI 1.03-7.69]; p<0.05), as were those who had undergone preoperative radiation (OR 3.55 [CI 2.03-6.20], p<0.05). Reconstruction with a radial forearm free flap was associated with a lower need for G-tube versus rectus abdominis (OR 0.25 [CI 0.08-0.83], p=0.02) and latissimus dorsi flap (OR 0.21 [CI 0.04-1.09], p=0.06). There was no difference in G-tube placement between those receiving pedicled flaps versus free flaps (OR 1.54 [CI 0.38-6.20], p=0.54)., Conclusions: Among patients with head and neck cancer undergoing resection with immediate pedicled or free flap reconstruction, advanced tumor stage and history of prior radiation therapy are associated with increased likelihood of G-tube placement. More randomized controlled trials are needed to develop a decision-making algorithm., Competing Interests: Declaration of Competing Interest None of the authors have any conflicts of interest and all authors contributed to the development of this research., (Copyright © 2022. Published by Elsevier Ltd.)
- Published
- 2023
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9. Fluorescence molecular optomic signatures improve identification of tumors in head and neck specimens.
- Author
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Chen Y, Streeter SS, Hunt B, Sardar HS, Gunn JR, Tafe LJ, Paydarfar JA, Pogue BW, Paulsen KD, and Samkoe KS
- Abstract
Background: Fluorescence molecular imaging using ABY-029, an epidermal growth factor receptor (EGFR)-targeted, synthetic Affibody peptide labeled with a near-infrared fluorophore, is under investigation for surgical guidance during head and neck squamous cell carcinoma (HNSCC) resection. However, tumor-to-normal tissue contrast is confounded by intrinsic physiological limitations of heterogeneous EGFR expression and non-specific agent uptake., Objective: In this preliminary study, radiomic analysis was applied to optical ABY-029 fluorescence image data for HNSCC tissue classification through an approach termed "optomics." Optomics was employed to improve tumor identification by leveraging textural pattern differences in EGFR expression conveyed by fluorescence. The study objective was to compare the performance of conventional fluorescence intensity thresholding and optomics for binary classification of malignant vs. non-malignant HNSCC tissues., Materials and Methods: Fluorescence image data collected through a Phase 0 clinical trial of ABY-029 involved a total of 20,073 sub-image patches (size of 1.8 × 1.8 mm
2 ) extracted from 24 bread-loafed slices of HNSCC surgical resections originating from 12 patients who were stratified into three dose groups (30, 90, and 171 nanomoles). Each dose group was randomly partitioned on the specimen-level 75%/25% into training/testing sets, then all training and testing sets were aggregated. A total of 1,472 standardized radiomic features were extracted from each patch and evaluated by minimum redundancy maximum relevance feature selection, and 25 top-ranked features were used to train a support vector machine (SVM) classifier. Predictive performance of the SVM classifier was compared to fluorescence intensity thresholding for classifying testing set image patches with histologically confirmed malignancy status., Results: Optomics provided consistent improvement in prediction accuracy and false positive rate (FPR) and similar false negative rate (FNR) on all testing set slices, irrespective of dose, compared to fluorescence intensity thresholding (mean accuracies of 89% vs. 81%, P = 0.0072; mean FPRs of 12% vs. 21%, P = 0.0035; and mean FNRs of 13% vs. 17%, P = 0.35)., Conclusions: Optomics outperformed conventional fluorescence intensity thresholding for tumor identification using sub-image patches as the unit of analysis. Optomics mitigate diagnostic uncertainties introduced through physiological variability, imaging agent dose, and inter-specimen biases of fluorescence molecular imaging by probing textural image information. This preliminary study provides a proof-of-concept that applying radiomics to fluorescence molecular imaging data offers a promising image analysis technique for cancer detection in fluorescence-guided surgery., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Chen, Streeter, Hunt, Sardar, Gunn, Tafe, Paydarfar, Pogue, Paulsen and Samkoe.)- Published
- 2023
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10. First demonstration of a novel nerve-targeting fluorophore in a cohort of ex vivo human tissues.
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Hebert KA, Bateman L, Parker D, Nunziata J, Paydarfar JA, Hong J, Kerr DA, Zanazzi GJ, Barth CW, Wang L, Gibbs SL, and Henderson ER
- Abstract
Iatrogenic nerve injury is a common complication across all surgical specialties. Better nerve visualization and identification during surgery will improve outcomes and reduce nerve injuries. The Gibbs Laboratory at Oregon Health and Science University has developed a library of near-infrared, nerve-specific fluorophores to highlight nerves intraoperatively and aid surgeons in nerve identification and visualization; the current lead agent is LGW16-03. Prior to this study, testing of LGW16-03 was restricted to animal models; therefore, it was unknown how LGW16-03 performs in human tissue. To advance LGW16-03 to clinic, we sought to test this current lead agent in ex vivo human tissues from a cohort of patients and determine if the route of administration affects LGW16-03 fluorescence contrast between nerves and adjacent background tissues (muscle and adipose). LGW16-03 was applied to ex vivo human tissue from lower limb amputations via two strategies: (1) systemic administration of the fluorophore using our first-in-kind model for fluorophore testing, and (2) topical application of the fluorophore. Results showed no statistical difference between topical and systemic administration. However, in vivo human validation of these findings is required.
- Published
- 2023
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11. Quantitative Evaluation of Aerosol Generation During In-Office Flexible Laryngoscopy.
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Bastien AJ, Wiredu K, Lee AY, Rees C, Hinchcliff MT, and Paydarfar JA
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- Humans, Bayes Theorem, Cohort Studies, Prospective Studies, SARS-CoV-2, COVID-19
- Abstract
Importance: Despite growing scientific knowledge and research, it is still unknown if office flexible laryngoscopy (FL) is aerosol generating and thereby potentially increases the risk of SARS-CoV-2 transmission. The limited literature that exists is conflicting, precluding formal conclusions., Objective: To determine whether FL is aerosol generating., Design, Setting, and Participants: This prospective cohort study included 134 patients seen in the otolaryngology clinic at a single tertiary care academic institution between February and May 2021. Two optical particle sizer instruments were used, quantifying particles ranging from 0.02 μm to 5 μm. Measurements were taken every 30 seconds, with sample periods of 15 seconds throughout the patient encounter. Instruments were located 12 inches from the patient's nares. Timing of events was recorded, including the start and end of physical examination, topical spray administration, start and end of laryngoscopy, and other potential aerosol-generating events (eg, coughing, sneezing). Data analysis was performed from February to May 2021., Exposures: Office examination and office FL., Main Outcomes and Measures: Bayesian online change point detection (OCPD) algorithm was used to detect significant change points (CPs) in this time-series data. The primary outcome was significant CP after FL compared with baseline physiologic variations, such as breathing and phonation., Results: Data were collected from 134 patients between February and May 2021. Ninety-one encounters involved FL. Of this group, 51 patients (56%) wore no mask over their mouth during FL. There was no statistically significant CP in either visits involving FL or visits where FL was not performed. Use of nasal spray did not result in CP in aerosol levels. Overall, neither the number of people present in the examination room, masks over patients' mouth, the duration of the visit, nor the duration of FL were associated with mean aerosol counts, regardless of the exposure. For larger aerosol sizes (≥1 μm), however, rooms with higher air exchange rates had significantly higher reductions in mean aerosol counts for visits involving FL., Conclusions and Relevance: The findings of this cohort study support that FL, including topical spray administration, is not a significant aerosol-generating procedure. The Bayesian OCPD model has a promising application for future aerosol studies in otolaryngology.
- Published
- 2022
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12. The submental island flap in head and neck reconstruction: A 10-year experience examining application, oncologic safety, and role of comorbidity.
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Paydarfar JA, Kahng PW, Polacco MA, and Zhao W
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Background: We present our experience on reconstructive versatility and risk of nodal transfer with the submental island flap (SIF). We also examine the role of comorbidity as a predictor of complications., Methods: Retrospective cohort study of patients undergoing SIF over 10-year period. Comorbidity determined using Adult Comorbidity Evaluation 27 index (ACE-27). Univariable/multivariable logistic regressions performed to determine association of these characteristics and rates of major complications., Results: Fifty-eight patients underwent SIF reconstruction, 27 (45%) patients had moderate/severe comorbidity, and 24 (41%) experienced major complication. Multivariable analysis identified ACE-27 scores >2 predictive of major flap complications (OR: 17.38, 95% CI: 1.96-153.74, p = .01) and medical complications (OR: 5.8, 95% CI: 1.11-30.23, p = .037). There were no cases of pathologic nodal transfer., Conclusion: The SIF is a versatile flap and oncologically safe in carefully selected patients. The ACE-27 index is strongly predictive of major postoperative complications., Level of Evidence: 4., Competing Interests: The authors report no conflicts of interest., (© 2022 The Authors. Laryngoscope Investigative Otolaryngology published by Wiley Periodicals LLC on behalf of The Triological Society.)
- Published
- 2022
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13. Quantifying Tumor and Vasculature Deformations during Laryngoscopy.
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Wu X, Pastel DA, Khan R, Eskey CJ, Shi Y, Sramek M, Paydarfar JA, and Halter RJ
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- Humans, Laryngoscopy methods, Microsurgery, Pharynx, Larynx diagnostic imaging, Neoplasms
- Abstract
Retractors and scopes used in head and neck surgery to provide adequate surgical exposure also deform critical structures in the region. Surgeons typically use preoperative imaging to plan and guide their tumor resections, however the large tissue deformation resulting from placement of retractors and scopes reduces the utility of preoperative imaging as a reliable roadmap. We quantify the extent of tumor and vasculature deformation in patients with tumors of the larynx and pharynx undergoing diagnostic laryngoscopy. A mean tumor displacement of 1.02 cm was observed between the patients' pre- and intra-operative states. Mean vasculature displacement at key bifurcation points was 0.99 cm. Registration to the hyoid bone can reduce tumor displacement to 0.67 cm and improve carotid stem angle deviations but increase overall vasculature displacement. The large deformation results suggest limitations in reliance on preoperative imaging and that using specific landmarks intraoperatively or having more intraoperative information could help to compensate for these deviations and ultimately improve surgical success., (© 2021. Biomedical Engineering Society.)
- Published
- 2022
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14. Clinicopathologic and Genomic Characterization of Inflammatory Myofibroblastic Tumors of the Head and Neck: Highlighting a Novel Fusion and Potential Diagnostic Pitfall.
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Kerr DA, Thompson LDR, Tafe LJ, Jo VY, Neyaz A, Divakar P, Paydarfar JA, Pastel DA, Shirai K, John I, Seethala RR, Salgado CM, Deshpande V, Bridge JA, Kashofer K, Brčić I, and Linos K
- Subjects
- Adolescent, Adult, Aged, Child, Diagnosis, Differential, Female, Gene Expression Profiling, Genetic Predisposition to Disease, Head and Neck Neoplasms pathology, Head and Neck Neoplasms therapy, Humans, Immunohistochemistry, In Situ Hybridization, Fluorescence, Male, Middle Aged, Neoplasm Recurrence, Local, Neoplasms, Muscle Tissue pathology, Neoplasms, Muscle Tissue therapy, Phenotype, Predictive Value of Tests, RNA-Seq, Treatment Outcome, United States, Biomarkers, Tumor genetics, Gene Fusion, Gene Rearrangement, Head and Neck Neoplasms genetics, Molecular Diagnostic Techniques, Neoplasms, Muscle Tissue genetics
- Abstract
Inflammatory myofibroblastic tumor (IMT) is a distinctive fibroblastic and myofibroblastic spindle cell neoplasm with an accompanying inflammatory cell infiltrate and frequent receptor tyrosine kinase activation at the molecular level. The tumor may recur and rarely metastasizes. IMT is rare in the head and neck region, and limited information is available about its clinicopathologic and molecular characteristics in these subsites. Therefore, we analyzed a cohort of head and neck IMTs through a multi-institutional approach. Fourteen cases were included in the provisional cohort, but 1 was excluded after molecular analysis prompted reclassification. Patients in the final cohort included 7 males and 6 females, with a mean age of 26.5 years. Tumors were located in the larynx (n=7), oral cavity (n=3), pharynx (n=2), and mastoid (n=1). Histologically, all tumors showed neoplastic spindle cells in storiform to fascicular patterns with associated chronic inflammation, but the morphologic spectrum was wide, as is characteristic of IMT in other sites. An underlying fusion gene event was identified in 92% (n=11/12) of cases and an additional case was ALK-positive by IHC but could not be evaluated molecularly. ALK represented the driver in all but 1 case. Rearrangement of ALK, fused with the TIMP3 gene (n=6) was most commonly detected, followed by 1 case each of the following fusion gene partnerships: TPM3-ALK, KIF5B-ALK, CARS-ALK, THBS1-ALK, and a novel alteration, SLC12A2-ROS1. The excluded case was reclassified as spindle cell rhabdomyosarcoma after detection of a FUS-TFCP2 rearrangement and retrospective immunohistochemical confirmation of rhabdomyoblastic differentiation, illustrating an important diagnostic pitfall. Two IMT patients received targeted therapy with crizotinib, with a demonstrated radiographic response. One tumor recurred but none metastasized. These results add to the growing body of evidence that kinase fusions can be identified in the majority of IMTs and that molecular analysis can lead to increased diagnostic accuracy and broadened therapeutic options for patients., Competing Interests: Conflicts of Interest and Source of Funding: NGS studies were supported by internal research funding from the D&R Institute of Pathology, Medical University of Graz, Austria. The authors have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)
- Published
- 2021
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15. CT for estimating adequacy of lymph node dissection in patients with squamous cell carcinoma of the head and neck.
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Rees CA, Litchman JH, Wu X, Servos MM, Kerr DA, Halter RJ, Pastel DA, and Paydarfar JA
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- Humans, Lymph Nodes diagnostic imaging, Lymph Nodes surgery, Lymphatic Metastasis, Squamous Cell Carcinoma of Head and Neck diagnostic imaging, Squamous Cell Carcinoma of Head and Neck surgery, Tomography, X-Ray Computed, Head and Neck Neoplasms diagnostic imaging, Head and Neck Neoplasms surgery, Lymph Node Excision
- Abstract
Background: Indices obtained from lymph node dissection specimens, specifically lymph node yield (LNY) and lymph node ratio (LNR), have prognostic significance in the setting of head and neck squamous cell carcinoma (HNSCCa). However, there are currently no validated tools to estimate adequacy of planned lymph node dissection using preoperative data. The present study sought to evaluate CT-derived estimates of lymphatic tissue volumes as a preoperative tool to guide cervical node dissection., Methods: Fifteen cervical lymph node dissections were performed in 14 subjects with HNSCCa. Preoperative CT-derived estimates of lymphatic tissue volumes were compared with gross pathology tissue volume estimates and pathologically-determined LNY., Results: Resected tissue volume (calculated using the triaxial ellipsoid method) correlates with CT-derived preoperative lymphatic volume estimates (r = 0.74, p = 0.003) while LNY does not(r = - 0.12, p = 0.67). When excluding pathologically enlarged lymph nodes ("refined" data), a negative correlation was observed between refined CT-derived volume estimates and refined LNY (r = - 0.65, p = 0.009)., Conclusion: In the setting of cervical lymph node dissection, CT-derived lymphatic volume estimates correlate with resected tissue volume, but refined CT-derived volume estimates correlate negatively with refined LNY., Trial Registration: Retrospectively registered., Level of Evidence: 4., (© 2021. The Author(s).)
- Published
- 2021
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16. First-In-Human Study in Cancer Patients Establishing the Feasibility of Oxygen Measurements in Tumors Using Electron Paramagnetic Resonance With the OxyChip.
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Schaner PE, Williams BB, Chen EY, Pettus JR, Schreiber WA, Kmiec MM, Jarvis LA, Pastel DA, Zuurbier RA, DiFlorio-Alexander RM, Paydarfar JA, Gosselin BJ, Barth RJ, Rosenkranz KM, Petryakov SV, Hou H, Tse D, Pletnev A, Flood AB, Wood VA, Hebert KA, Mosher RE, Demidenko E, Swartz HM, and Kuppusamy P
- Abstract
Objective: The overall objective of this clinical study was to validate an implantable oxygen sensor, called the 'OxyChip', as a clinically feasible technology that would allow individualized tumor-oxygen assessments in cancer patients prior to and during hypoxia-modification interventions such as hyperoxygen breathing., Methods: Patients with any solid tumor at ≤3-cm depth from the skin-surface scheduled to undergo surgical resection (with or without neoadjuvant therapy) were considered eligible for the study. The OxyChip was implanted in the tumor and subsequently removed during standard-of-care surgery. Partial pressure of oxygen (pO
2 ) at the implant location was assessed using electron paramagnetic resonance (EPR) oximetry., Results: Twenty-three cancer patients underwent OxyChip implantation in their tumors. Six patients received neoadjuvant therapy while the OxyChip was implanted. Median implant duration was 30 days (range 4-128 days). Forty-five successful oxygen measurements were made in 15 patients. Baseline pO2 values were variable with overall median 15.7 mmHg (range 0.6-73.1 mmHg); 33% of the values were below 10 mmHg. After hyperoxygenation, the overall median pO2 was 31.8 mmHg (range 1.5-144.6 mmHg). In 83% of the measurements, there was a statistically significant (p ≤ 0.05) response to hyperoxygenation., Conclusions: Measurement of baseline pO2 and response to hyperoxygenation using EPR oximetry with the OxyChip is clinically feasible in a variety of tumor types. Tumor oxygen at baseline differed significantly among patients. Although most tumors responded to a hyperoxygenation intervention, some were non-responders. These data demonstrated the need for individualized assessment of tumor oxygenation in the context of planned hyperoxygenation interventions to optimize clinical outcomes., Competing Interests: PK has multiple patents issued for OxyChip; but declares no competing interest. AF and HS are co-owners of Clin-EPR, a company that sells EPR spectrometers for research use in human subjects. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Schaner, Williams, Chen, Pettus, Schreiber, Kmiec, Jarvis, Pastel, Zuurbier, DiFlorio-Alexander, Paydarfar, Gosselin, Barth, Rosenkranz, Petryakov, Hou, Tse, Pletnev, Flood, Wood, Hebert, Mosher, Demidenko, Swartz and Kuppusamy.)- Published
- 2021
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17. Image-guided surgery in otolaryngology: A review of current applications and future directions in head and neck surgery.
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Bessen SY, Wu X, Sramek MT, Shi Y, Pastel D, Halter R, and Paydarfar JA
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- Humans, Otolaryngology, Surgery, Computer-Assisted
- Abstract
Image-guided surgery (IGS) has become a widely adopted technology in otolaryngology. Since its introduction nearly three decades ago, IGS technology has developed rapidly and improved real-time intraoperative visualization for a diverse array of clinical indications. As usability, accessibility, and clinical experiences with IGS increase, its potential applications as an adjunct in many surgical procedures continue to expand. Here, we describe the basic components of IGS and review both the current state and future directions of IGS in otolaryngology, with attention to current challenges to its application in surgery of the nonrigid upper aerodigestive tract., (© 2021 Wiley Periodicals LLC.)
- Published
- 2021
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18. Tensor Veli Palatinopexy as a Novel Treatment for Eustachian Tube Dysfunction: A Cadaveric Feasibility Study.
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Eisen EA, Wu X, Rees CA, Pastel DA, Paydarfar JA, and Saunders JE
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- Adult, Cadaver, Feasibility Studies, Humans, Ear Diseases surgery, Eustachian Tube, Palatal Muscles surgery, Suture Techniques
- Abstract
Objective: To demonstrate the feasibility of a novel procedure whereby a suture is placed transorally in the tensor veli palatini muscle to tighten it, thereby dilating the cartilaginous portion of the eustachian tube (ET)., Study Design: The study design was a prospective cadaveric experiment to examine the feasibility of a novel treatment for ET dysfunction., Setting: Academic medical center in a research-oriented operating room with intraoperative computed tomography (CT) capabilities., Methods: Seven fresh-frozen cadaver heads were obtained, each of which was thawed for 36 hours prior to use. The preprocedural volumes of the cartilaginous ET were measured by filling the ET with an iodine-containing radiocontrast agent via the nasopharynx and then obtaining CT images. Submucosal flaps in the soft palate were raised, and sutures were placed in the tensor veli palatini bilaterally to increase tension. After completion of the procedure, contrast placement and CT imaging were repeated. Three-dimensional models of the ETs were created, and the volumes were measured and compared., Results: Of the 14 ETs evaluated, 13 showed an increase in postprocedure volume. On average, postprocedure volumes showed a 57% increase from preprocedure volumes (mean relative change, 57.1%; P = .013)., Conclusion: Placement of a tension-holding suture in the tensor veli palatini muscle can reliably dilate the cartilaginous portion of the ET. Such a procedure may be useful in the treatment of ET dysfunction.
- Published
- 2021
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19. A System for Characterizing Intraoperative Force Distribution During Operative Laryngoscopy.
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Ponukumati AS, Wu X, Kahng PW, Skinner J, Paydarfar JA, and Halter RJ
- Subjects
- Humans, Laryngoscopy, Microsurgery, Laryngoscopes, Larynx, Oral Surgical Procedures
- Abstract
Objective: This study aimed to create and validate an integrated data acquisition system for gauging the force distribution between a laryngoscope and soft-tissue during trans-oral surgery., Methods: Sixteen piezoresistive force sensors were interfaced to a laryngoscope and custom maxillary tooth guard. A protocol for calibrating the laryngoscope and maxilla sensors was developed using a motor-controlled linear stage and force measurements were validated against a digital scale. The system was initially tested during suspension laryngoscopy on three cadaver heads mounted on a cadaver head-holder. Intraoperative data was also collected from three patients undergoing head and neck tumor resection., Results: Mean calibration error of the scope sensors was less than 150 g (n = 3) and mean maxilla sensor error was less than 200 g (n = 3). Peak scope mag-forces of 8.09 ± 6.61 kg and peak maxilla forces of 7.62 ± 4.57 kg were experienced during the cadaver trials. The peak scope sensor mag-force recorded during the intraoperative cases was 24.7 ± 4.53 kg, and the peak maxilla force was 22.0 ± 4.60 kg., Conclusion: The data acquisition system was successfully able to record intraoperative force distribution data. The usefulness of this technology in informing surgeons during trans-oral surgery should be further evaluated in patients with varying anatomic and procedural characteristics., Significance: Creation of a low-cost, integrated force-sensing system allows for the characterization of retraction forces at anatomic sites including the pharynx and larynx, brain, and abdomen. Real-time force detection provides surgeons with valuable intraoperative feedback and can be used to improve deformation models at various anatomic sites.
- Published
- 2020
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20. Spontaneous regression of squamous cell carcinoma in the setting of dental infection and needle biopsy.
- Author
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Divakar P, Khan MJ, Polacco M, Kerr DA, and Paydarfar JA
- Abstract
To our knowledge, this is the first reported case of spontaneous regression of squamous cell carcinoma within a lymph node. We speculate that prior dental infection, fever, and biopsy incited an antitumor immune reaction., Competing Interests: None of the authors have any financial or personal conflicts of interest., (© 2020 The Authors. Clinical Case Reports published by John Wiley & Sons Ltd.)
- Published
- 2020
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21. Considerations for NIR-I and short-wave infrared (SWIR) fluorescence imaging within a clinical operating room.
- Author
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Byrd BK, Wirth DJ, Paydarfar JA, Tafe LJ, Samkoe KS, Paulsen KD, and Davis SC
- Abstract
Short-wave infrared (SWIR/NIR-II) fluorescence imaging has received increased attention for use in fluorescence-guided surgery (FGS) due to the potential for higher resolution imaging of subsurface structures and reduced autofluorescence compared to conventional NIR-I imaging. As with any fluorescence imaging modality introduced in the operating room, an appropriate accounting of contaminating background signal from other light sources in the operating room is an important step. Herein, we report the background signals in the SWIR and NIR-I emitted from commonly-used equipment in the OR, such as ambient and operating lights, LCD screens and surgical guidance systems. These results can guide implementation of protocols to reduce background signal.
- Published
- 2020
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22. Radiation exposure alters airway deformability and bony structure displacement during laryngoscopy.
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Rees CA, Wu X, Eisen EA, Pastel DA, Halter RJ, and Paydarfar JA
- Abstract
Background: Prior therapeutic radiation exposure in the setting of head and neck malignancies is associated with difficult airway instrumentation. We sought to characterize the anatomic changes that produce this phenotype., Study Design: Retrospective review., Methods: Five individuals with prior radiation therapy to the upper aerodigestive tract (previously irradiated) and 10 with no prior history of therapeutic radiation exposure (nonirradiated) were enrolled. Computed tomography images obtained before and during laryngoscope insertion ("uninstrumented" and "instrumented", respectively) were used to reconstruct three-dimensional representations of the pharyngeal airway, hyoid, and mandible., Results: In the instrumented state, pharyngeal airway volumes were significantly greater in nonirradiated subjects relative to previously irradiated subjects ( P = .01), and overall translation of both the hyoid and mandible was also greater in nonirradiated subjects ( P = .01 and .04, respectively)., Conclusion: Individuals with prior therapeutic radiation exposure to the upper aerodigestive tract differ from nonirradiated subjects with respect to airway deformation and bony structure translation during laryngoscopy., Level of Evidence: 4., (© 2019 The Authors. Laryngoscope Investigative Otolaryngology published by Wiley Periodicals, Inc. on behalf of The Triological Society.)
- Published
- 2019
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23. Multi-modal Framework for Image-guided Trans-oral Surgery with Intraoperative Imaging and Deformation Modeling.
- Author
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Wu X, Fels S, Paydarfar JA, Halter RJ, Sanchez CA, Kahng PW, Rees CA, Ponukumati AS, Eisen EA, Pastel DA, Borgard H, and Lloyd JE
- Subjects
- Imaging, Three-Dimensional, Laryngoscopes, Laryngoscopy, Oral Surgical Procedures, Surgery, Computer-Assisted
- Abstract
Treatment of throat cancers have improved due to minimally-invasive trans-oral approaches. Surgeons rely on preoperative imaging to guide their resection; however, large tissue deformations occur during trans-oral procedures due to placement of necessary retractors and laryngoscopes which hinders the surgeon's ability to accurately assess tumor extent and location of critical structures. We propose an image-guided framework utilizing intraoperative imaging and deformation modeling to improve surgeon accuracy and confidence. A CT-compatible laryngoscopy system previously developed was evaluated in this framework. Intraoperative images were acquired during laryngoscopy; force-sensing capabilities were enabled in the laryngoscope; and tracking of the scope and anatomic features was trialed. Tissue deformation and displacement were quantified and determined to be extensive, with values <; 4.6 cm in the tongue, <; 1.8 cm in bony structures, and <; 108.9 cm
3 in airway volume change. Surgical navigation using intraoperative imaging and tracking was evaluated. Preliminary assessment of deformation modeling showed potential to supplement intraoperative imaging. Future work will involve streamlined integration of the components of this framework.- Published
- 2019
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24. Improving target localization during trans-oral surgery with use of intraoperative imaging.
- Author
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Kahng PW, Wu X, Ramesh NP, Pastel DA, Halter RJ, and Paydarfar JA
- Subjects
- Cadaver, Humans, Intraoperative Period, Oral Surgical Procedures education, Oropharyngeal Neoplasms diagnosis, Oropharyngeal Neoplasms surgery, Surgery, Computer-Assisted education, Education, Medical, Graduate methods, Imaging, Three-Dimensional, Laryngoscopy methods, Oral Surgical Procedures methods, Otolaryngology education, Surgery, Computer-Assisted methods
- Abstract
Purpose: Trans-oral surgery provides a less invasive means for the surgical management of upper aerodigestive tract malignancies but is limited in its ability to readily assess submucosal tumor extent and location of critical structures intraoperatively. We sought to determine surgeons' baseline target localization accuracy during operative laryngoscopy with preoperative imaging alone and then assess for improvement in localization accuracy when presented with intraoperative CT imaging capturing soft tissue deformation., Methods: Fiducial beads were placed submucosally in four cadaver heads. "Preoperative" (PO) and "intraoperative" (IO) neck CTs were acquired before and during suspension laryngoscopy using a CT-compatible laryngoscopy system. Surgeons attempted to localize submucosal fiducials beads using pins based on sequential review of PO and IO images., Results: Mean total error (TE) decreased from 12.8 ± 9.9 to 10 ± 7.5 mm from PO to IO (P < 0.001), respectively. TE for base of tongue and vallecula decreased by 1.7 ± 6.7 mm (P = 0.015). Right-sided structures were most exposed by scope positioning and experienced a TE reduction of 4.8 ± 9.3 mm (P < 0.001). Task completion time decreased from PO to IO by 26% (P < 0.001)., Conclusions: Intraoperative imaging significantly improves localization accuracy and task efficiency when targeting submucosal beads in cadaver heads during operative laryngoscopy.
- Published
- 2019
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25. Initial experience with image-guided surgical navigation in transoral surgery.
- Author
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Paydarfar JA, Wu X, and Halter RJ
- Subjects
- Aged, Carcinoma, Squamous Cell diagnostic imaging, Carcinoma, Squamous Cell surgery, Contrast Media, Fiducial Markers, Humans, Laryngeal Neoplasms diagnostic imaging, Laryngeal Neoplasms surgery, Laryngocele diagnostic imaging, Laryngocele surgery, Laryngoscopy, Laser Therapy, Male, Microscopy, Confocal, Middle Aged, Natural Orifice Endoscopic Surgery instrumentation, Tongue Neoplasms diagnostic imaging, Tongue Neoplasms surgery, Laryngoscopes, Multidetector Computed Tomography, Natural Orifice Endoscopic Surgery methods, Surgery, Computer-Assisted
- Abstract
Background: Surgical navigation using image guidance may improve the safety and efficacy of transoral surgery (TOS); however, preoperative imaging cannot be accurately registered to the intraoperative state due to deformations resulting from placement of the laryngoscope or retractor. This proof of concept study explores feasibility and registration accuracy of surgical navigation for TOS by utilizing intraoperative imaging., Methods: Four patients undergoing TOS were recruited. Suspension laryngoscopy was performed with a CT-compatible laryngoscope. An intraoperative contrast enhanced CT scan was obtained and registered to fiducials placed on the neck, face, and laryngoscope., Results: All patients were successfully scanned and registered. Registration accuracy within the pharynx and larynx was 1 mm or less. Target registration was confirmed by localizing endoscopic and surface structures to the CT images. Successful tracking was performed in all 4 patients., Conclusion: For surgical navigation during TOS, although a high level of registration accuracy can be achieved by utilizing intraoperative imaging, significant limitations of the existing technology have been identified. These limitations, as well as areas for future investigation, are discussed., (© 2018 Wiley Periodicals, Inc.)
- Published
- 2019
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26. Cadaver head holder for transoral surgical simulation.
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Chang J, Wu X, Kahng PW, Halter RJ, and Paydarfar JA
- Subjects
- Cadaver, Equipment Design, Humans, Laser Therapy instrumentation, Microsurgery instrumentation, Oral Surgical Procedures instrumentation, Robotic Surgical Procedures instrumentation, Simulation Training methods
- Published
- 2018
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27. Quantifying Anatomic Deformations During Laryngoscopy.
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Wu X, Paydarfar JA, and Halter RJ
- Subjects
- Adult, Aged, Female, Humans, Male, Middle Aged, Intraoperative Care methods, Laryngoscopy methods, Models, Biological, Tomography, X-Ray Computed
- Abstract
For a variety of head and neck cancers, specifically those of the oropharynx, larynx, and hypopharynx, minimally invasive trans-oral approaches have been developed to reduce perioperative and long-term morbidity. However, in trans-oral surgical approaches anatomical deformation due to instrumentation, specifically placement of laryngoscopes and retractors, present a significant challenge for surgeons relying on preoperative imaging to resect tumors to negative margins. Quantifying the deformation due to instrumentation is needed in order to develop predictive models of operative deformation. In order to study this deformation, we used a CT/MR-compatible laryngoscopy system in concert with intraoperative CT imaging. 3D models of preoperative and intraoperative anatomy were generated. Mandible and hyoid displacements as well as tongue deformations were quantified for eight patients undergoing diagnostic laryngoscopy. Across patients, we found on average 1.3 cm of displacement for these anatomic structures due to laryngoscope insertion. On average, the maximum displacement for certain tongue regions exceeded 4 cm. The anatomical deformations quantified here can serve as a reference for describing how the upper aerodigestive tract anatomy changes during instrumentation and may be helpful in developing predictive models of intraoperative upper aerodigestive tract deformation.
- Published
- 2018
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28. Diagnostic Value of Lingual Tonsillectomy in Unknown Primary Head and Neck Carcinoma Identification After a Negative Clinical Workup and Positron Emission Tomography-Computed Tomography.
- Author
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Sudoko CK, Polacco MA, Gosselin BJ, and Paydarfar JA
- Abstract
Objective: Diagnostic rates of unknown primary head and neck carcinoma (UPHNC) using lingual tonsillectomy (LT) are highly variable. This study sought to determine the diagnostic value of LT in UPHNC identification using strict inclusion criteria and definitions to produce a more accurate estimate of diagnosis rate., Methods: In this retrospective chart review, records of patients who underwent LT for UPHNC were reviewed. Inclusion criteria included absence of suspicious findings on physical exam and positron emission tomography-computed tomography as well as negative biopsies after panendoscopy and palatine tonsillectomy. Following inclusion criteria, 16 patients were reviewed. A systematic literature review on LT for the workup of CUP was also performed., Results: LT was performed using transoral robotic surgery (TORS), transoral laser microsurgery (TLM), or transoral microsurgery with cautery (TMC). Following LT, primary tumor was identified in 4 patients out of 16. Detection rate by technique was 1/6, 2/7, and 1/3 for TORS, TLM, and TMC respectively. Postoperative bleeding occurred in three patients (19%); however, this was not related to the LT. Following literature review, 12 studies were identified; however, only 3 had enough data to compare against. All three studies had a cohort with suspicious findings on clinical exam. A total of 34 patients had a negative workup, with no suspicious findings on clinical exam and subsequently received an LT., Conclusion: This study suggests that LT should be considered initially in the diagnostic algorithm for UPHNC. This study can increase the patient size in this cohort by approximately 47%.
- Published
- 2018
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29. Management of the thyroid gland during laryngectomy.
- Author
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Li SX, Polacco MA, Gosselin BJ, Harrington LX, Titus AJ, and Paydarfar JA
- Subjects
- Adult, Aged, Aged, 80 and over, Carcinoma, Squamous Cell pathology, Carcinoma, Squamous Cell surgery, Cartilage pathology, Cartilage surgery, Female, Head and Neck Neoplasms pathology, Head and Neck Neoplasms surgery, Humans, Hypopharyngeal Neoplasms pathology, Hypopharyngeal Neoplasms surgery, Incidence, Laryngeal Neoplasms pathology, Male, Middle Aged, Neoplasm Invasiveness, Predictive Value of Tests, Retrospective Studies, Squamous Cell Carcinoma of Head and Neck, Thyroid Gland pathology, Thyroid Neoplasms epidemiology, Thyroid Neoplasms secondary, Thyroidectomy methods, Treatment Outcome, Laryngeal Neoplasms surgery, Laryngectomy methods, Thyroid Gland surgery, Thyroid Neoplasms surgery, Thyroidectomy statistics & numerical data
- Abstract
Objectives: This study aimed to: describe the incidence of thyroid gland involvement in advanced laryngeal cancer, analyse patterns of spread to the thyroid and elucidate predictors of thyroid involvement., Methods: A retrospective review was performed on patients who underwent laryngectomy from 1991 to 2015 as a primary or salvage treatment for squamous cell carcinoma of the larynx, hypopharynx or base of tongue. The incidence of thyroidectomy during total laryngectomy, type of thyroidectomy, incidence of gland involvement, route of spread, and positive predictors of spread were analysed and reported., Results: A total of 188 patients fit the inclusion criteria. Of these, 125 (66 per cent) underwent thyroidectomy. The thyroid was involved in 10 of the 125 patients (8 per cent), 9 by direct extension and 1 by metastasis. Cartilage invasion was a predictor of thyroid gland involvement, with a positive predictive value of 26 per cent., Conclusion: There is a low incidence of thyroid gland involvement in laryngeal carcinoma. Most cases of gland involvement occurred by direct extension. Thyroidectomy during laryngectomy should be considered for advanced stage tumours with cartilage invasion.
- Published
- 2017
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30. Parotidectomy using the Harmonic scalpel: ten years of experience at a rural academic health center.
- Author
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Polacco MA, Pintea AM, Gosselin BJ, and Paydarfar JA
- Subjects
- Academic Medical Centers, Adult, Aged, Blood Loss, Surgical prevention & control, Cohort Studies, Female, Follow-Up Studies, Humans, Male, Middle Aged, Operative Time, Otorhinolaryngologic Surgical Procedures methods, Parotid Neoplasms pathology, Retrospective Studies, Rural Health Services, Surgical Instruments, Treatment Outcome, Laser Coagulation methods, Otorhinolaryngologic Surgical Procedures instrumentation, Parotid Gland surgery, Parotid Neoplasms surgery
- Abstract
Background: Parotidectomy is one of the most commonly performed procedures by otorhinolaryngologists. Traditionally dissection is performed with a combination of a steel scalpel and bipolar cautery; however, starting in the early 2000s, the Harmonic scalpel has provided an alternative method for dissection and hemostasis. The purpose of this study is to compare operative time, blood loss, complications, and cost between the Harmonic scalpel and steel scalpel plus bipolar cautery for superficial and total parotidectomy., Methods: Retrospective cohort of patients who underwent superficial or total parotidectomy with the Harmonic or cold steel between 2000 and 2015. Across 255 patients, comparison between operative time, blood loss, complications, and cost was performed., Results: Superficial parotidectomy was performed on 120 patients with the Harmonic and 54 with steel scalpel. Total parotidectomy was performed on 59 patients using the Harmonic and 22 patients with cold steel. For superficial parotidectomy, the Harmonic reduced operative time (216 ± 42 vs. 234 ± 54 min, p = 0.03) and decreased blood loss (28 ± 19 vs. 76 ± 52 mls, p < 0.05). With total parotidectomy the Harmonic decreased operative time (240 ± 42 vs. 288 ± 78 min, p = 0.01) and reduced blood loss (38 ± 21 mls vs. 85 ± 55 mls, p < 0.05). There were no differences in complication rates between groups. Harmonic use was associated with surgical cost reduction secondary to reduced operative times., Conclusions: The Harmonic scalpel decreases blood loss and operating time for superficial and total parotidectomy. Shorter operative times may decrease the overall cost of parotidectomy.
- Published
- 2017
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31. Improving Access to Head and Neck Cancer Surgical Services through the Incorporation of Associate Providers.
- Author
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Paydarfar JA, Gosselin BJ, and Tietz AM
- Subjects
- Efficiency, Female, Humans, Male, Patient Satisfaction, Pilot Projects, Waiting Lists, Workforce, Appointments and Schedules, Head and Neck Neoplasms surgery, Health Services Accessibility, Medical Oncology, Physician Assistants, Quality Improvement, Referral and Consultation statistics & numerical data
- Abstract
Objective: The urgent nature of head and neck cancer referrals often results in overbooked schedules, access delays, and patient, physician, and staff dissatisfaction. The goal of this study is to examine how incorporation of associate providers (APs) into a head and neck tumor clinic (HNTC) can improve access., Methods: Scheduling data for the Dartmouth-Hitchcock HNTC 2 years prior (January 2011 to December 2012) and 2 years subsequent (January 2013 to December 2014) to program initiation were abstracted, including number of new patients seen per month, third available for new and established patients, overbooked hours, surgeon productivity, and patient satisfaction scores., Results: New patients seen per month increased from 44 ± 4 to 60 ± 5 (P < .001). Third available for new patients decreased from 56 ± 4 to 27 ± 2 days and from 43 ± 3 to 35 ± 2 days for follow-ups (P < .001). Overbooked hours decreased from 14.7 ± 3.1 to 8.6 ± 1.7 hours (P < .001). Surgeon productivity remained stable (109% ± 11% vs 113% ± 6%, P = .56). Patient satisfaction in seeing APs versus surgeons was comparable (94 ± 2 vs 94 ± 3, P = .79)., Discussion: Incorporation of APs into the HNTC increases the number of new patients seen by the surgeon, decreases wait times for all appointments, and decreases overbooking while maintaining patient satisfaction and surgeon productivity., Implications for Practice: AP incorporation significantly improves access to head and neck surgical services. With improved access, new cancer patients could start treatment sooner, potentially affecting outcome., (© American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.)
- Published
- 2016
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32. MRI- and CT-Compatible Polymer Laryngoscope: A Step toward Image-Guided Transoral Surgery.
- Author
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Paydarfar JA, Wu X, and Halter RJ
- Subjects
- Humans, Magnetic Resonance Imaging, Polymers, Tomography, X-Ray Computed, Laryngoscopes, Surgery, Computer-Assisted instrumentation
- Published
- 2016
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33. The anterolateral thigh fold-over flap for total and subtotal glossectomy reconstruction.
- Author
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Paydarfar JA, Freed GL, and Gosselin BJ
- Subjects
- Adult, Female, Follow-Up Studies, Humans, Male, Middle Aged, Outcome Assessment, Health Care, Retrospective Studies, Thigh, Free Tissue Flaps transplantation, Glossectomy methods, Plastic Surgery Procedures methods
- Abstract
Background: We present a fold-over technique for total and subtotal glossectomy reconstruction utilizing the ALT flap with the goal of increasing soft tissue bulk., Methods: Retrospective review of total and subtotal glossectomy patients undergoing ALT fold-over flap reconstruction from January 2007 to December 2012., Results: Eight patients fit inclusion criteria. Average length of follow-up was 35 months. There were no flap failures. At last follow-up, no patients were tracheostomy dependent. Six out of 8 patients (75%) did not require a g-tube and were able to maintain their weight. Speech intelligibility was good in 6/8 patients (75%)., Conclusions: The ALT fold-over flap technique provides sufficient bulk to allow decannulation and airway protection as well as PO intake in most patients. Given the minimal donor site morbidity, it is our technique of choice for total and subtotal glossectomy defects. © 2016 Wiley Periodicals, Inc. Microsurgery 36:297-302, 2016., (© 2016 Wiley Periodicals, Inc.)
- Published
- 2016
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34. Nontender Parotid Mass in a Young Asian Man.
- Author
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Ran C, Tafe LJ, and Paydarfar JA
- Subjects
- Carcinoma surgery, Humans, Male, Parotid Neoplasms surgery, Radiography, Young Adult, Asian People, Carcinoma diagnostic imaging, Carcinoma pathology, Parotid Neoplasms diagnostic imaging, Parotid Neoplasms pathology
- Published
- 2015
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35. MCM2/TOP2A (ProExC) immunohistochemistry as a predictive marker in head and neck mucosal biopsies.
- Author
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Jenson EG, Baker M, Paydarfar JA, Gosselin BJ, Li Z, and Black CC
- Subjects
- Biopsy, Carcinoma, Squamous Cell pathology, Case-Control Studies, Diagnosis, Differential, Disease Progression, Head and Neck Neoplasms pathology, Humans, Mucous Membrane pathology, Poly-ADP-Ribose Binding Proteins, Precancerous Conditions pathology, Predictive Value of Tests, Squamous Cell Carcinoma of Head and Neck, Time Factors, Antigens, Neoplasm analysis, Biomarkers, Tumor analysis, Carcinoma, Squamous Cell chemistry, DNA Topoisomerases, Type II analysis, DNA-Binding Proteins analysis, Head and Neck Neoplasms chemistry, Immunohistochemistry, Minichromosome Maintenance Complex Component 2 analysis, Mucous Membrane chemistry, Precancerous Conditions chemistry
- Abstract
Mucosal biopsies from the head and neck are often small and poorly oriented, which impedes diagnostic interpretation, especially in patients with a history of cancer, being monitored for recurrence. A cocktail of antibodies targeted against DNA topoisomerase IIA and mini-chromosome maintenance protein 2 (MCM2/TOP2A, ProExC), markers of aberrant S-phase induction, have been used with success as a diagnostic adjunct in the evaluation of squamous dysplasia of the uterine cervix. We tested the utility in head and neck biopsies to see if ProExC could be used to discriminate reactive/inflammatory from true pre-neoplasia. Sixty-four archival biopsies were selected from patients who presented to the surgeon with an indication for biopsy to "rule out" dysplasia. Histologically, all biopsies showed nonspecific atypia that was difficult to discriminate from dysplasia. Twenty-three of the patients progressed to squamous carcinoma and the rest remained benign over five years follow-up. Cases stained with ProExC by IHC methods showed a significant pattern of expression (p=0.026). The staining was greatest in patients without a history of prior head and neck cancer but was not significant. Our results show that ProExC, used in conjunction with the H&E slide, can enhance the predictive power of a mucosal biopsy in a cohort of patients., (Copyright © 2014 Elsevier GmbH. All rights reserved.)
- Published
- 2014
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36. Use of cervicothoracic anatomy as a guide for directed drainage of descending necrotizing mediastinitis.
- Author
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Erkmen CP, Wang H, Czum J, and Paydarfar JA
- Subjects
- Abscess surgery, Adult, Humans, Male, Mediastinitis etiology, Neck diagnostic imaging, Neck surgery, Necrosis, Tomography, X-Ray Computed, Tooth Diseases surgery, Treatment Outcome, Abscess complications, Drainage, Mediastinitis surgery, Mediastinum diagnostic imaging, Mediastinum surgery, Tooth Diseases complications
- Abstract
Descending necrotizing mediastinitis is a potentially lethal infection originating from the oropharynx. Adequate abscess drainage is crucial to successful treatment. We present novel management of descending necrotizing mediastinitis using a series of anterior mediastinal incisions adjoined by Penrose drains. The success of this treatment was dependent on radiographic documentation of infection confined to the anterior cervicothoracic plane., (Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)
- Published
- 2012
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37. Parotidectomy: a 17-year institutional experience at a rural academic medical center.
- Author
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Maddox PT, Paydarfar JA, and Davies L
- Subjects
- Abscess etiology, Academic Medical Centers, Adenoma, Pleomorphic surgery, Adolescent, Adult, Aged, Aged, 80 and over, Carcinoma secondary, Carcinoma surgery, Child, Child, Preschool, Cysts surgery, Facial Muscles, Female, Hematoma etiology, Humans, Male, Middle Aged, Muscle Weakness etiology, Parotid Neoplasms secondary, Parotid Neoplasms surgery, Postoperative Complications, Registries, Rural Population, Seroma etiology, Sialadenitis surgery, Sweating, Gustatory etiology, Young Adult, Parotid Gland surgery
- Abstract
Objectives: We describe the parotidectomy experience at a single rural institution over 17 years., Methods: We retrieved the records of all patients who underwent parotidectomy for any nontrauma indication (current procedural terminology codes 42410, 42415, 42420, 42425, and 42426) from January 1990 to June 2007 at Dartmouth-Hitchcock Medical Center, a rural medical center that provides both primary and tertiary care to a local population of 14,000, with a catchment area of 600,000 people. Information was collected on initial patient presentation, use of fine-needle aspiration, extent of surgery, final pathologic diagnosis, and complications., Results: We performed 341 parotidectomy procedures in 334 patients. The largest number of malignancies came from metastatic tumors; squamous cell carcinoma was the most common (37% of malignancies). The most common presenting complaint overall was a painless mass. The most common complication was facial weakness in 17% (57 of 341); 36 of the 57 cases of facial weakness (63%) were associated with surgery for malignancy. The most common benign tumor was pleomorphic adenoma (114 of 186; 61%). Mucoepidermoid carcinoma was the most common primary parotid malignancy (12%)., Conclusions: In this 17-year rural case series of all parotidectomy procedures done for nontrauma indications, the largest number of malignancies came from metastatic tumors. Although facial nerve paralysis is not a common complication, it occurs most often when surgery is performed for either primary or metastatic malignancy. Surgeons will benefit from this information as they counsel patients who are considering parotidectomy.
- Published
- 2012
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38. Pathology quiz case 1. Basal cell adenocarcinoma (BCAC) of a minor salivary gland.
- Author
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Maddox PT, Paydarfar JA, Black CC, and Eskey CJ
- Subjects
- Adenocarcinoma surgery, Adult, Deglutition Disorders etiology, Humans, Male, Salivary Gland Neoplasms surgery, Salivary Glands, Minor surgery, Adenocarcinoma pathology, Salivary Gland Neoplasms pathology, Salivary Glands, Minor pathology
- Published
- 2010
- Full Text
- View/download PDF
39. Auricular leishmaniasis mimicking squamous cell carcinoma.
- Author
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Khorsandi-Ashtiani MT, Hasibi M, Yazdani N, Paydarfar JA, Sadri F, Mirashrafi F, and Kouhi A
- Subjects
- Adult, Diagnosis, Differential, Humans, Male, Carcinoma, Squamous Cell pathology, Ear Neoplasms pathology, Leishmaniasis, Cutaneous pathology, Skin Neoplasms pathology
- Abstract
Objectives: We report a rare case of auricular involvement by leishmaniasis, in order to demonstrate the importance of thorough investigation of cutaneous head and neck lesions, and also the importance of inclusion of infections such as leishmaniasis in the differential diagnosis of auricular lesions, especially in endemic areas., Case History: A 42-year-old man with multiple lesions on his head, neck and hands was referred to our centre. He had the following lesions: a painful, crusted, 8 x 8 cm plaque with indurated margins on the left parotid region and auricle; a red papule on the right temporal region; an ulcerative lesion on the skin overlying the proximal interphalangeal joint of the fifth finger of the right hand; and a bluish papule on the neck. Although histopathological examination of the Geimsa-stained specimen was misleading, a direct smear prepared from biopsies showed amastigotes, and therapy resulted in complete recovery., Conclusion: Leishmaniasis can be both under- or over-diagnosed. Especially in endemic areas, parasitic causes of chronic infections should always be kept in mind.
- Published
- 2009
- Full Text
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40. Functional study of four neurotoxins as inhibitors of post-traumatic nerve regeneration.
- Author
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Paydarfar JA and Paniello RC
- Subjects
- Animals, Facial Nerve Injuries therapy, Female, Nerve Crush, Rats, Rats, Inbred Lew, Recurrent Laryngeal Nerve Injuries, Tibial Nerve drug effects, Botulinum Toxins pharmacology, Doxorubicin pharmacology, Nerve Regeneration drug effects, Neurotoxins pharmacology, Phenol pharmacology, Vincristine pharmacology
- Abstract
Objectives/hypothesis: Chemical inhibition of nerve regeneration was studied as a potential adjunct in the treatment of injuries to the facial or recurrent laryngeal nerve. We propose that by treating selected muscles with an inhibitor of nerve regeneration shortly after injury, synkinesis may be controlled., Study Design: Nerve regeneration after crush injury was studied in the rat posterior tibial and sciatic nerves, well-established models for the study of peripheral nerve injuries., Methods: Four days after controlled crush injury to the posterior tibial nerve, the gastrocnemius muscle was injected with saline (control, n = 8), phenol (n = 6), doxorubicin (n = 6), or vincristine (n = 11). Injection without crush injury was performed using vincristine (n = 4) or botulinum toxin (n = 4). Four rats underwent crush injury to the sciatic nerve followed 4 days later by botulinum toxin injection to the gastrocnemius muscle. The percent of functional recovery (%FR) of the nerve was assessed using walking track analysis., Results: Vincristine significantly retarded nerve regeneration. Five weeks after injury, %FR returned to normal in controls, as well as in the phenol, doxorubicin, and botulinum toxin groups, while in the vincristine group %FR was less than 60% of baseline (P <.0001). Vincristine injections without crush injury showed no significant reduction in print length factor. Functional recovery in the botulinum/crush group was more rapid than the botulinum without crush group., Conclusions: Application of vincristine to the gastrocnemius muscle significantly inhibits regeneration of the posterior tibial nerve after crush injury. Botulinum toxin does not prolong functional recovery after nerve injury; rather, crush injury protects against the prolonged chemodenervation seen with botulinum toxin. Doxorubicin and phenol injection did not prolong functional recovery at the doses tested.
- Published
- 2001
- Full Text
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41. Factors related to outcome of salvage therapy for isolated cervical recurrence of squamous cell carcinoma in the previously treated neck: a multi-institutional study.
- Author
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Krol BJ, Righi PD, Paydarfar JA, Cheng ET, Smith RM, Lai DC, Bhargava V, Piccirillo JF, Hayes JT, Lue AJ, Scher RL, Weisberger EC, Wilson KM, Tran LE, Rizk N, Pellitteri PK, and Terris DJ
- Subjects
- Adult, Aged, Analysis of Variance, Carcinoma, Squamous Cell pathology, Combined Modality Therapy, Disease-Free Survival, Female, Head and Neck Neoplasms pathology, Head and Neck Neoplasms therapy, Humans, Logistic Models, Male, Middle Aged, Neoplasm Recurrence, Local pathology, Probability, Proportional Hazards Models, Registries, Retrospective Studies, Risk Factors, Survival Rate, Carcinoma, Squamous Cell mortality, Carcinoma, Squamous Cell therapy, Cause of Death, Head and Neck Neoplasms mortality, Neoplasm Recurrence, Local mortality, Neoplasm Recurrence, Local therapy, Salvage Therapy
- Abstract
Objective: The goal was to identify factors associated with the outcome of salvage therapy for patients with isolated cervical recurrences of squamous cell carcinoma in the previously treated neck (ICR-PTN)., Study Design and Settings: A tumor registry search for ICR-PTN patients was performed at 7 participating institutions, and the charts were reviewed. Kaplan-Meier plots for survival and time until re-recurrence were used to evaluate the significance of associated variables., Results: Median survival and time until re-recurrence were both 11 months. Survival was better in patients with the following characteristics: nonsurgical initial neck treatment, negative initial disease resection margins, no history of prior recurrence, ipsilateral location of the ICR-PTN relative to the primary, and use of surgical salvage., Conclusions: By pooling the experience of 7 US tertiary care medical centers, we have identified 5 factors that are associated with outcome of salvage therapy for ICR-PTN., Significance: Consideration of these factors, as well as the reviewed literature, should facilitate patient selection for salvage protocols.
- Published
- 2000
- Full Text
- View/download PDF
42. Phase resetting of the respiratory oscillator by carotid sinus nerve stimulation in cats.
- Author
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Paydarfar D, Eldridge FL, and Paydarfar JA
- Subjects
- Animals, Carotid Sinus cytology, Cats, Computer Simulation, Electric Stimulation, Evoked Potentials physiology, Models, Neurological, Oscillometry, Respiratory Mechanics physiology, Carotid Sinus innervation, Carotid Sinus physiology, Respiration physiology
- Abstract
1. Stimulation of the carotid sinus nerve causes an increase in inspiratory (I) and expiratory (E) neural activities. If central respiratory oscillation is generated by an attractor-cycle process, an increase in its activity can be caused by a centrifugal perturbation of state. We evaluated this hypothesis by comparing the respiratory oscillator's phase responses to carotid sinus nerve stimulations in cats to the phase responses of an attractor-cycle oscillator, the Bonhoeffer-van der Pol (BvP) equations, subjected to centrifugal perturbations. 2. We recorded phrenic activity in seven anaesthetized, vagotomized, glomectomized, paralysed and servo-ventilated cats. Carotid sinus nerve (CSN) stimulation with 0.5-0.8 s electrical pulse trains increased the immediate cycle period and delayed the onset of breaths after stimulation in a highly predictable manner, with the exception that strong stimuli (25 Hz, 0.25-0.90 V) caused unpredictable responses when given at the I-E or the E-I transitions. The resetting plots exhibited focal gaps corresponding to these unpredictable responses, and the size of the gaps increased with increases in the strength of CSN stimulation. Type 0 resetting was not achieved despite the large perturbations in rhythm induced by CSN stimulation. 3. Centrifugal perturbations of the BvP oscillator resulted in phase responses which were similar to those found in the animal experiments. The BvP cycle had two critical phases at which phase resetting was highly irregular and neighbouring state trajectories were highly divergent. The resetting plots had focal gaps that increased in size with increases in the strength of perturbation. The gaps did not represent true discontinuity because at higher computational resolution the resetting plots appeared to be steep but smooth portions of topological Type 1 resetting curves. 4. These studies support the concept that brief carotid sinus nerve stimulations cause a transient outward displacement of the central respiratory state away from its attractor cycle, in contrast to the unidirectional displacements that accompany midbrain reticular or superior laryngeal nerve stimulations. The findings define particular geometrical relationships between oscillatory state trajectories of the rhythm generator and perturbed state trajectories induced by inputs to the oscillator. These relationships provide a framework for developing and testing the validity of neural models of the respiratory oscillator.
- Published
- 1998
- Full Text
- View/download PDF
43. The wagon wheel illusion in movies and reality.
- Author
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Purves D, Paydarfar JA, and Andrews TJ
- Subjects
- Eye Movements physiology, Humans, Models, Neurological, Motion Pictures, Photic Stimulation, Motion Perception physiology, Optical Illusions physiology
- Abstract
Wheels turning in the movies or in other forms of stroboscopic presentation often appear to be rotating backward. Remarkably, a similar illusion is also seen in continuous light. The occurrence of this perception in the absence of intermittent illumination suggests that we normally see motion, as in movies, by processing a series of visual episodes.
- Published
- 1996
- Full Text
- View/download PDF
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