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Featured researches published by John F. Pallanch.


Laryngoscope | 1982

Adenocarcinoma and adenoma of the middle ear

John F. Pallanch; Louis H. Weiland; Thomas J. McDonald; George W. Facer; Stephen G. Harner

Primary middle ear glandular tumors of the adenocarcinoma and adenoma types are rare. The terminology used in describing them is quite varied. Some investigators presume that a distinct recognizable group of these tumors are benign, but because of the rarity of the lesions, such conclusions have been difficult to verify. We review the literature of these lesions and report 11 additional cases. The course was documented in 25 cases in the literature; 20 of these were reported to be benign over periods of follow‐up from 1 month to 10 years, and 5 were fatal. Among our patients, 5 had a benign course, 3 died of causes related to the tumor, and 3 had persistence of their lesion and substantial consequent morbidity. We emphasize the slow growth and elusive nature of these lesions. Histologic evidence of mitoses, roentgenologic evidence of bony destruction, and cranial nerve involvement were factors consistent with a poor prognosis. The origin of these tumors may vary. A similarity to paragangliomas is noted. The ultimate course of these tumors cannot always be predicted from the histologic appearance. Early surgical removal appears to be the most successful therapy.


PLOS ONE | 2010

Gene Transcription Changes in Asthmatic Chronic Rhinosinusitis with Nasal Polyps and Comparison to Those in Atopic Dermatitis

Douglas A. Plager; Jane Kahl; Yan W. Asmann; Allan E. Nilson; John F. Pallanch; Oren Friedman; Hirohito Kita

Background Asthmatic chronic rhinosinusitis with nasal polyps (aCRSwNP) is a common disruptive eosinophilic disease without effective medical treatment. Therefore, we sought to identify gene expression changes, particularly those occurring early, in aCRSwNP. To highlight expression changes associated with eosinophilic epithelial inflammation, we further compared the changes in aCRSwNP with those in a second eosinophilic epithelial disease, atopic dermatitis (AD), which is also closely related to asthma. Methods/Principal Findings Genome-wide mRNA levels measured by exon array in both nasosinus inflamed mucosa and adjacent polyp from 11 aCRSwNP patients were compared to those in nasosinus tissue from 17 normal or rhinitis subjects without polyps. Differential expression of selected genes was confirmed by qRT-PCR or immunoassay, and transcription changes common to AD were identified. Comparison of aCRSwNP inflamed mucosa and polyp to normal/rhinitis tissue identified 447 differentially transcribed genes at ≥2 fold-change and adjusted p-value<0.05. These included increased transcription of chemokines localized to chromosome 17q11.2 (CCL13, CCL2, CCL8, and CCL11) that favor eosinophil and monocyte chemotaxis and chemokines (CCL18, CCL22, and CXCL13) that alternatively-activated monocyte-derived cells have been shown to produce. Additional transcription changes likely associated with Th2-like eosinophilic inflammation were prominent and included increased IL1RL1 (IL33 receptor) and EMR1&3 and decreased CRISP2&3. A down-regulated PDGFB-centric network involving several smooth muscle-associated genes was also implicated. Genes at 17q11.2, genes associated with alternative activation or smooth muscle, and the IL1RL1 gene were also differentially transcribed in AD. Conclusions/Significance Our data implicate several genes or gene sets in aCRSwNP and eosinophilic epithelial inflammation, some that likely act in the earlier stages of inflammation. The identified gene expression changes provide additional diagnostic and therapeutic targets for aCRSwNP and other eosinophilic epithelial diseases.


American Journal of Roentgenology | 2010

Dose and Image Quality Evaluation of a Dedicated Cone-Beam CT System for High-Contrast Neurologic Applications

Lifeng Yu; Thomas J. Vrieze; Michael R. Bruesewitz; James M. Kofler; David R. DeLone; John F. Pallanch; E. Paul Lindell; Cynthia H. McCollough

OBJECTIVE The purpose of our study was to evaluate the dose and image quality performance of a dedicated cone-beam CT (CBCT) scanner in comparison with an MDCT scanner. MATERIALS AND METHODS The conventional dose metric, CT dose index (CTDI), is no longer applicable to CBCT scanners. We propose to use two dose metrics, the volume average dose and the mid plane average dose, to quantify the dose performance in a circular cone-beam scan. Under the condition of equal mid plane average dose, we evaluated the image quality of a CBCT scanner and an MDCT scanner, including high-contrast spatial resolution, low-contrast spatial resolution, noise level, CT number uniformity, and CT number accuracy. RESULTS For the sinus scanning protocol, the CBCT system had comparable high-contrast resolution and inferior low-contrast resolution to those obtained with the MDCT scanner when the doses were matched (mid plane average dose 9.2 mGy). The CT number uniformity and accuracy were worse on the CBCT scanner. The image artifacts caused by beam hardening and scattering were also much more severe on the CBCT system. CONCLUSION With a matched radiation dose, the CBCT system for sinus study has comparable high-contrast resolution and inferior low-contrast resolution relative to the MDCT scanner. Because of the more severe image artifacts on the CBCT system due to the small field of view and the lack of accurate scatter and beam-hardening correction, the utility of the CBCT system for diagnostic tasks related to soft tissue should be carefully assessed.


Mayo Clinic Proceedings | 2009

Uvulopalatopharyngoplasty in the Management of Obstructive Sleep Apnea: The Mayo Clinic Experience

Akram Khan; Kannan Ramar; Supriya Maddirala; Oren Friedman; John F. Pallanch; Eric J. Olson

OBJECTIVE To assess the role of uvulopalatopharyngoplasty (UPPP) in the treatment of obstructive sleep apnea (OSA) using polysomnography (PSG) data within 6 months before and after surgery. PATIENTS AND METHODS We analyzed PSG and body mass index (BMI) data from patients with OSA who were 18 years or older and who underwent UPPP between January 1, 1988, and August 31, 2006. RESULTS Sixty-three patients (51 men [81.0%]; mean ± SD age, 42.1±13.9 years; mean ± SD BMI, 34.9±7.2) underwent PSG a mean ± SD of 50±47 days before and 88.5±34.0 days after UPPP. Surgical cure was defined as a postoperative apnea-hypopnea index (AHI) of 5 or less. Fifteen patients (24%) achieved a surgical cure. Twenty-one patients (33%) had a postoperative AHI of 10 or less, whereas 32 (51%) achieved a 50% or greater reduction in AHI and/or an AHI of 20 or less. No significant changes were noted in BMI before and 6 months after UPPP. Patients who attained an AHI of 5 or less were younger (mean ± SD age, 35.9±13.1 vs 44±13.7 years; P =.05), had lower BMIs (mean ± SD, 30.8±6.5 vs 34.6±6.6; P =.05), and had less severe OSA (mean ± SD AHI, 38.1±33.6 vs 69.6±32.8; P =.004). Of the 48 patients (76%) with a post-UPPP AHI greater than 5, 35 (56%) received continuous positive airway pressure, with a mean reduction in pressure of 1.4 cm H 2 O (95% confidence interval, -0.4 to -2.4 cm H 2 O). CONCLUSION Independent of changes in BMI, in our retrospective analysis, UPPP achieved an AHI of 5 or less in 24% and an AHI of 10 or less in 33% of patients with OSA who underwent PSG 6 months before and after surgery. In those with residual OSA who received continuous positive airway pressure, the required pressure setting decreased by 1.4 cm H 2 O.


International Forum of Allergy & Rhinology | 2013

Three-dimensional volumetric computed tomographic scoring as an objective outcome measure for chronic rhinosinusitis: clinical correlations and comparison to Lund-Mackay scoring.

John F. Pallanch; Lifeng Yu; David R. DeLone; Rich Robb; David R. Holmes; Jon J. Camp; Phil Edwards; Cynthia H. McCollough; Jens U. Ponikau; Amy C. Dearking; John I. Lane; Andrew N. Primak; Aaron T. Shinkle; John B. Hagan; Evangelo Frigas; Joseph J. Ocel; Nicole M. Tombers; Rizwan Siwani; Nicholas M. Orme; Kurtis B. Reed; Nivedita Jerath; Robinder Dhillon; Hirohito Kita

We aimed to test the hypothesis that three‐dimensional (3D) volume‐based scoring of computed tomography (CT) images of the paranasal sinuses was superior to Lund‐Mackay CT scoring of disease severity in chronic rhinosinusitis (CRS). We determined correlation between changes in CT scores (using each scoring system) with changes in other measures of disease severity (symptoms, endoscopic scoring, and quality of life) in patients with CRS treated with triamcinolone.


Otolaryngology-Head and Neck Surgery | 1982

Prosthetic Closure of Nasal Septal Perforations

John F. Pallanch; George W. Facer; Eugene B. Kern; William B. Westwood

One hundred seventy-one patients had closure of symptomatic nasal septal perforations by insertion of a Silastic nasal septal prosthesis between June 1972 and August 1981. Follow-up revealed that successful closure of the defect was accomplished in 73% of cases, with reduction in crusting and epistaxis and improvement in nasal respiration in many cases. Prefabricated prostheses have been effective in treating smaller perforations. The treatment of four patients with unusually large septal perforations by custom-carved prostheses sized using computerized axial tomographic scanning is described.


American Journal of Rhinology & Allergy | 2010

Three-dimensional CT reconstruction and virtual endoscopic study of the ostial orientations of the frontal recess.

Ligy Thomas; John F. Pallanch

Background Safe and efficient endoscopic frontal sinus surgery requires a thorough knowledge of the location of the frontal sinus outflow tract. This study was designed to describe the prevalence of the different frontal recess cells and 3D analysis by virtual endoscopy of their ostial orientation in relation to the frontal ostium. Methods Fifty high-resolution CT scans (100 sides) of disease-free paranasal sinuses were reviewed using triplanar and virtual 3D analysis. The prevalence and ostial locations of the frontal recess cells and the relationship of the various ostia to the frontal sinus ostium were mapped and analyzed. Results The cell type, prevalence, and most common relationship of the cells ostium to the frontal ostium were intersinus septal cells, 7% medial and anterior; Kuhn type 1 cells, 28%, lateral and anterior; Kuhn type 2 cells, 6%, anterior and lateral; Kuhn type 3 cells, 11%, medial or lateral; supraorbital ethmoid cells, 11%, posterior; suprabullar cells, 68%, posterior; and frontal bullar cells, 16%, posterior or lateral. In 35% of the sides, none of the aforementioned cell types were found. There were many blind recesses that were seen in all locations except anterolateral to the frontal ostium. Openings of adjacent pneumatized middle turbinates were often posteromedial to the frontal ostium. Agger nasi cells were present in at least 86%, opening lateral to frontal ostium. Conclusion Frontal outflow tract mapping by virtual endoscopy and knowledge of the ostial configurations will help surgeons perform more efficient and accurate surgery particularly for minimally invasive approaches including balloon dilation.


Otolaryngology-Head and Neck Surgery | 2013

Computed Tomography Scans as an Objective Measure of Disease Severity in Chronic Rhinosinusitis

Micah M. Likness; John F. Pallanch; David A. Sherris; Hirohito Kita; Terry Mashtare; Jens U. Ponikau

Objectives A truly objective method of measuring disease severity in chronic rhinosinusitis (CRS) has only recently existed. We evaluated computed tomography (CT) scans of CRS patients using this novel objective 3D computerized system and compared results with a novel 2D computerized analysis of a single coronal slice through the osteomeatal complex (OMC) and subjective methods including Lund-Mackay and Zinreich’s modified Lund-Mackay. Study Design Prospective multicenter study. Setting Two academic tertiary referral centers. Subjects and Methods Forty-six adults with a diagnosis of CRS underwent CT examination and received an intramuscular triamcinolone injection, dosage weight dependent, followed by CT scan 4 to 5 weeks later. Recruitment lasted 21 months. Scans were evaluated with all 4 scoring methods over 5 months. Results The Lin’s concordance class correlation (CCC) of the OMC method revealed the best correlation to the 3D volumetric computerized values (0.915), followed by the Zinreich (0.904) and Lund-Mackay methods (0.824). Posttreatment results demonstrated that both the OMC (0.824) and Zinreich’s (0.778) methods had strong agreement with the 3D volumetric methods and were very sensitive to change, whereas the Lund-Mackay (0.545) had only moderate agreement. Conclusion Computerized CT analysis provides the most comprehensive, objective, and reproducible method of measuring disease severity and is very sensitive to change induced by treatment intervention. A 2D coronal image through the OMC provides a valid, user-friendly method of assessing CRS and is representative of CRS severity in all sinuses. Zinreich’s subjective method correlated well overall, but the Lund-Mackay method lagged behind in disease representation and sensitivity to change.


International Forum of Allergy & Rhinology | 2015

Volumetric computed tomography analysis of the olfactory cleft in patients with chronic rhinosinusitis.

Zachary M. Soler; John F. Pallanch; Eugene Ritter Sansoni; Cameron S. Jones; Lauren A. Lawrence; Rodney J. Schlosser; Jess C. Mace; Timothy L. Smith

Commonly used computed tomography (CT) staging systems for chronic rhinosinusitis (CRS) focus on the sinuses and do not quantify disease in the olfactory cleft. The goal of the current study was to determine whether precise measurements of olfactory cleft opacification better correlate with olfaction in patients with CRS.


Laryngoscope | 2012

Mapping the Frontal Sinus Ostia Using Virtual Endoscopy

Amy C. Dearking; John F. Pallanch

To determine the relative location of the frontal sinus opening to other frontal cells using virtual endoscopy; and to assess whether the relative location of the frontal sinus ostium can be predicted.

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