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Dive into the research topics where Hwan Jung Roh is active.

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Featured researches published by Hwan Jung Roh.


Laryngoscope | 2007

New staging system for sinonasal inverted papilloma in the endoscopic era.

Steven B. Cannady; Pete S. Batra; Nathan B. Sautter; Hwan Jung Roh; Martin J. Citardi

Objectives: Advanced endoscopic techniques have emerged as the preferred treatment modality for sinonasal inverted papilloma (IP); however, a staging system that provides prognostic information has not yet been developed. This study aims to develop a clinically relevant staging system for IP managed with the endoscopic approach as the primary surgical modality.


American Journal of Rhinology | 2004

Endoscopic resection of sinonasal malignancies: a preliminary report.

Hwan Jung Roh; Pete S. Batra; Martin J. Citardi; Joung H. Lee; William E. Bolger; Donald C. Lanza

Background A minimally invasive endoscopic approach for the management of sinonasal malignancy offers several advantages including excellent illumination, maximal preservation of uninvolved vital structures, and sparing of facial incisions. The purpose of this study was to evaluate the outcome and morbidity of endoscopic resection with or without combined radiotherapy and/or chemotherapy. Methods Forty-seven patients with sinonasal malignancy were diagnosed and/or treated with an endoscopic approach at The Cleveland Clinic Foundation and The University of Pennsylvania Medical Center from 1996 to 2003. Nineteen patients fulfilled the study criteria and had a minimally invasive endoscopic resection. Fifteen patients were treated with curative intent and four patients underwent palliative resection. Results The mean age was 56.9 (9–78 years) years and the mean follow-up period was 26.4 months. Combined radiation with or without chemotherapy pre- or postoperatively was given to 15 of 19 (78.9%) patients. Thirteen patients were resected strictly with an endoscopic approach and six patients were resected in combination with neurosurgery. There were no peri- and postoperative deaths. The local recurrence (LR) rate was 26.3% (5/19) and the distant metastasis rate was 15.8% (3/19). Overall survival rate (OS) was 78.9% (15/19) at a mean follow-up duration of 32.1 (4–74 months) months. The disease-free survival (DFS) rate was 68.4% (13/19) by clinical, endoscopic, and radiographic surveillance at a mean follow-up duration of 33.1 months. Patients treated with curative intent had LR, OS, and DFS rates of 21.4, 85.7, and 85.7%, respectively, and the patients treated for palliation had LR, OS, and DFS rates of 40, 60, and 15%, respectively. Conclusion Minimally invasive endoscopic resection of sinonasal malignancy in combination with adjunctive therapies reduces treatment morbidity and yields LR, OS, and DFS rates that are comparable with traditional anterior craniofacial approaches.


International Forum of Allergy & Rhinology | 2016

International Consensus Statement on Allergy and Rhinology: Rhinosinusitis

Richard R. Orlandi; Todd T. Kingdom; Peter H. Hwang; Timothy L. Smith; Jeremiah A. Alt; Fuad M. Baroody; Pete S. Batra; Manuel Bernal-Sprekelsen; Neil Bhattacharyya; Rakesh K. Chandra; Alexander G. Chiu; Martin J. Citardi; Noam A. Cohen; John M. DelGaudio; Martin Desrosiers; Hun Jong Dhong; Richard Douglas; Berrylin J. Ferguson; Wytske J. Fokkens; Christos Georgalas; Andrew Goldberg; Jan Gosepath; Daniel L. Hamilos; Joseph K. Han; Richard J. Harvey; Peter Hellings; Claire Hopkins; Roger Jankowski; Amin R. Javer; Robert C. Kern

Isam Alobid, MD, PhD1, Nithin D. Adappa, MD2, Henry P. Barham, MD3, Thiago Bezerra, MD4, Nadieska Caballero, MD5, Eugene G. Chang, MD6, Gaurav Chawdhary, MD7, Philip Chen, MD8, John P. Dahl, MD, PhD9, Anthony Del Signore, MD10, Carrie Flanagan, MD11, Daniel N. Frank, PhD12, Kai Fruth, MD, PhD13, Anne Getz, MD14, Samuel Greig, MD15, Elisa A. Illing, MD16, David W. Jang, MD17, Yong Gi Jung, MD18, Sammy Khalili, MD, MSc19, Cristobal Langdon, MD20, Kent Lam, MD21, Stella Lee, MD22, Seth Lieberman, MD23, Patricia Loftus, MD24, Luis Macias‐Valle, MD25, R. Peter Manes, MD26, Jill Mazza, MD27, Leandra Mfuna, MD28, David Morrissey, MD29, Sue Jean Mun, MD30, Jonathan B. Overdevest, MD, PhD31, Jayant M. Pinto, MD32, Jain Ravi, MD33, Douglas Reh, MD34, Peta L. Sacks, MD35, Michael H. Saste, MD36, John Schneider, MD, MA37, Ahmad R. Sedaghat, MD, PhD38, Zachary M. Soler, MD39, Neville Teo, MD40, Kota Wada, MD41, Kevin Welch, MD42, Troy D. Woodard, MD43, Alan Workman44, Yi Chen Zhao, MD45, David Zopf, MD46


Stem Cells and Development | 2010

Adipose-Derived Stromal Cells Inhibit Allergic Airway Inflammation in Mice

Hye-Kyung Park; Kyu-Sup Cho; Hee-Young Park; Dong Hoon Shin; Yoon-Keun Kim; Jin Sup Jung; Soon Kew Park; Hwan Jung Roh

Allergic asthma is an inflammatory airway disease caused by T helper type 2 (Th2)-driven immune responses. Recent studies have demonstrated that adipose-derived stromal cells (ASC) have an immunosuppressive effect on T-cell activity. This study was performed to investigate whether ASC can inhibit Th2-dependent allergic airway inflammation in mice. BALB/c mice were sensitized to ovalbumin (OVA) by intraperitoneal injection. To investigate the effect of ASC on the development of asthma phenotypes, 2 × 10⁶ ASC were injected intravenously before OVA challenge. We evaluated the airway hyperresponsiveness (AHR), the proportion of eosinophils and cytokine production in bronchoalveolar lavage fluid (BALF), airway inflammation, and the intracellular cytokine staining of T cells in the BALF and spleen. Airway hyperresponsiveness, airway eosinophilia, and mucus production were markedly reduced after ASC administration before OVA challenge. The increased interleukin (IL)-4, IL-5, and transforming growth factor (TGF)-β1 levels in the BALF after OVA challenge were significantly reduced by the administration of ASC. This inhibition was accompanied by decreased IL-4(+) CD4(+) T cells and increased interferon (IFN)-γ(+) CD4(+) T cells in the BALF and spleen. The results of this study suggest that ASC administration before an allergen challenge inhibits AHR, lung inflammation, and Th2 cytokine production induced by an allergen challenge through inhibition of Th2 cell activity.


American Journal of Rhinology | 2004

Inflammation and the pathogenesis of inverted papilloma.

Hwan Jung Roh; Gary W. Procop; Pete S. Batra; Martin J. Citardi; Donald C. Lanza

Background Despite existing clinical and histopathological evidence, the role of inflammation in the pathogenesis of inverted papilloma (IP) is not well understood. The goal of this study was to describe the inflammatory cell component present in sinonasal papilloma (SP), with the intention of further defining the existence of inflammation in IP and perhaps gaining insight into IP pathophysiology. Methods Computerized database analysis was performed to identify all patients with SP who underwent surgery at the Cleveland Clinic Foundation between 1995 and 2001. Histopathological features of all SP were reviewed and semiquantitative analysis of the inflammatory cells present was performed. IP was histopathologically graded into four categories by the extent of inflammatory infiltrate and cellular atypia. Statistical analysis of the inflammatory cell component present in the epithelial layer of exophytic papilloma and IP was performed. Results SP was classified into three types: cylindrical papilloma (5% [2/41]), exophytic squamous papilloma (34% [14/41]), and IP (61% [25/41]). Twenty-eight instances of IP in 25 patients were identified. Altogether, 11% were grade I (3/28), 54% were grade II (15/28), 25% were grade III (7/28), and 11% were grade IV (3/28). The inflammatory cell population was significantly greater in IP compared with other SPs and greater in grades I and II IP when compared with grade III and IV IP. Conclusion Inflammatory cells were identified as a significant cell population in IP, whereas it was less commonly encountered in other forms of SP. The proposed IP staging system may serve as the foundation for improved understanding of IP and, ultimately, may help to predict recurrence or apparent malignant transformation.


American Journal of Rhinology | 2007

Comparison of open versus endoscopic resection of inverted papilloma.

Nathan B. Sautter; Steven B. Cannady; Martin J. Citardi; Hwan Jung Roh; Pete S. Batra

Background Lateral rhinotomy with medial maxillectomy has served as the standard for surgical management of inverted papilloma (IP) in the pre–endoscopic era; since the late 1980s, endoscopic techniques have emerged as the minimally invasive alternative. The objective of this study was twofold: (1) to compare operative parameters, complications, and recurrence rates and (2) predictive factors for recurrence for open versus endoscopic cases of IP resection. Methods Retrospective data analysis was performed on 68 patients with histopathologically confirmed IP treated at a tertiary care medical center from January 1983 to May 2005. Parameters for comparison included operative time (OT), estimated blood loss (EBL), length of hospital stay (HS), complications, and recurrence rate. Predictive factors for recurrence including open versus endoscopic cases, primary versus secondary IP, and tumor by Krouse stage were analyzed. Results The average age at time of presentation was 57.4 years with a male/female ratio of 2.2:1. Forty-nine patients underwent endoscopic resection, 13 patients underwent open resection, and 6 patients underwent limited open resection. Average OT and EBL were statistically similar for the three groups, whereas the average HS was statistically shorter (p = 0.002) for the endoscopic group. Biopsy-proven recurrence was noted in 11 (22%) endoscopic cases, 5 (39%) open cases, and 3 (50%) limited open cases. After reresection, all patients were free of disease. Mean follow-up was 16 months, 56 months, and 69 months for the endoscopic, open, and limited open groups, respectively. Analysis of predictive factors indicated that the surgical approach and primary versus secondary IP, regardless of approach, did not statistically impact recurrence rate. Chi-square analysis illustrated that patients with advanced-stage IP had a higher risk of recurrence (p = 0.002), regardless of surgical technique. Conclusion In this series, endoscopic resection of IP was associated with shorter HS and equivalent EBL and OT compared with the open groups. The overall recurrence rate was lower in the endoscopic group with acceptable morbidity compared with the open and limited open groups. Thus, the endoscopic approach may serve as a superior alternative to the open approaches for successful extirpation of IP.


American Journal of Rhinology | 2007

The prevalence of human papilloma virus infection in sinonasal inverted papilloma specimens classified by histological grade

Jee Yeon Kim; Jong Keun Yoon; Martin J. Citardi; Pete S. Batra; Hwan Jung Roh

Background Histological analysis suggests that inverted papilloma (IP) tumorigenesis may occur through a stepwise series of discrete events. The association between human papilloma virus (HPV) and IP has been described at varying incidences. The purpose of this study was to evaluate the prevalence of the HPV subtypes in a large series of IP specimens classified by histological grade. Methods Fifty-seven paraffin-embedded specimens of Korean population were available for study. Each specimen was graded according to a four-stage histological grading system (stages I and II, benign IP; stage III, dysplastic IP; stage IV, carcinoma arising from IP). A representative section of IP specimen was isolated through laser capture microdissection (7.5- to 10-μm laser spot size). Subsequently, DNA extraction and HPV genotyping with the HPV DNA chip test (Biomed Lab Co., Seoul, Korea) was performed. The HPV DNA chip contained 22 type-specific probes that consisted of 15 high-risk subtypes and 7 low-risk subtypes. Results Histological grading was as follows: 5, grade I; 23, grade II; 22, grade III; and 7, grade IV. Seven of 57 specimens (12.3%) showed HPV DNA. All of the HPV+ cases showed HPV DNA in early grade (grades I and II) IP lesions. No higher grade (grades III and IV) IP tumors showed HPV DNA. Among the seven HPV+ cases, five were high-risk subtypes and two were unspecified subtypes. Conclusion HPV infection, mainly high-risk subtypes, occurs in benign IP as an early event during the multistep tumorigenesis of IP. Cumulative other genetic insults may be required to progress from benign IP (grades I and II) to dysplastic IP (grade III) and carcinoma arising from IP (grade IV).


American Journal of Rhinology & Allergy | 2009

Frontal sinus inverted papilloma: surgical strategy based on the site of attachment.

Bit Na Yoon; Pete S. Batra; Martin J. Citardi; Hwan Jung Roh

Background The surgical management of inverted papilloma (IP) involving the frontal sinus (FS) remains a challenge given the narrow confines of the frontal recess and the close proximity to critical structures. The objective of this study was to elucidate a surgical strategy for management of frontal sinus IP based on the site of attachment. Methods A retrospective chart review was performed on 18 patients with FS IP treated at the Pusan National University Hospital and the Cleveland Clinic Foundation between 1998 and 2008. Results The mean age was 53.8 years with a male/female ratio of 13:5. The sites of tumor attachment included the medial wall (MW; six cases), posterior wall (PW; five cases), diffuse (all walls involved; five cases), intersinus septal cell (three cases), lateral wall (two cases), and anterior wall (two cases). IP involvement was unifocal in 10 cases and multifocal in 8 cases. Unifocal IP attached to the MW or PW was managed strictly by endoscopic frontal sinusotomy (EFS) in five of six cases (83%). Multifocal IP required endoscopic modified Lothrop (EML) and/or open approaches (endoscopic frontal trephination [EFT], four, osteoplastic flap [OPF], one) in seven of eight cases (88%). One additional patient with bilateral anterior table involvement required OPF. Four (22%) patients developed recurrences. Two were managed by EML, one was managed by EFS, and one was managed by EFT and EFS. Two patients developed cerebrospinal fluid leaks that were managed endoscopically without untoward effects. All patients were free of disease at the time of last evaluation with a mean follow-up of 36.6 months. Conclusion Frontal sinus IP with MW or PW involvement can generally be managed by standard EFS. Tumors with multifocal involvement often require EML, along with adjunct EFT in selected cases. OPF can be avoided as the primary surgical approach in most patients with sinonasal papilloma of FS.


Otolaryngology-Head and Neck Surgery | 2003

The impact of fiducial distribution on headset-based registration in image-guided sinus surgery

P. Daniel Knott; Calvin R. Maurer; Ryan P. Gallivan; Hwan Jung Roh; Martin J. Citardi

OBJECTIVE: The objective of this study was to assess registration error due to fiducial configuration for the ENT headsets for the CBYON Suite (CBYON, Mountain View, CA) and InstaTrak (GEMS Navigation and Visualization, Waukesha, WI). STUDY DESIGN: Axial CT scans (1-mm slice thickness) were obtained of for 24 cadaveric heads using the CBYON headset and for 23 cadaveric heads using the GEMS headset. The CBYON and GEMS NAV software were used to calculate the fiducial registration error (FRE). Fiducial localization error (FLE) was estimated from FRE. Theoretical target registration error (TRE) was calculated at 11 targets. RESULTS: The FRE for CBYON and GEMS NAV was 0.69 mm and 0.27 mm, respectively. The theoretical TRE for CBYON and GEMS NAV was 0.41 mm and 0.30 mm, respectively. The theoretical TRE was greater at targets posterior in the sinus cavities. CONCLUSION: Theoretical TRE values for both ENT headsets are less than clinically observed TRE. Clinically observed TRE is likely due to repositioning accuracy. EBM rating: B-2.


American Journal of Rhinology | 2004

Quantitative computer-aided computed tomography analysis of sphenoid sinus anatomical relationships.

Martin J. Citardi; Ryan P. Gallivan; Pete S. Batra; Calvin R. Maurer; Torsten Rohlfing; Hwan Jung Roh; Donald C. Lanza

Background This study describes a novel computer-generated anatomic symmetry plane as a framework for the quantitative description of sphenoid sinus anatomy. The aim of this study was to (1) determine relationships and distances between a midline sphenoid reference point (called the central sphenoid point [CSP]) and lateral sphenoid wall structures and (2) assess the incidence of anterior clinoid process (ACP) pneumatization and pterygoid recess (PR) pneumatization. Methods Axial computed tomography (CT) scans (1-mm slice thickness) were obtained on a VolumeZoom CT scanner (Siemens Medical, Erlangen, Germany). Mathematically derived anatomic symmetry planes were created using custom postprocessing software. A standardized review of each CT scan using surgical planning software (CBYON Suite version 2.6; CBYON, Mountain View, CA) was performed. The CSP was defined as a reference point in the midline sagittal plane at the intersection of the vertical sellar face and the horizontal sellar floor. Results A total of 128 sides in 64 cadaveric specimens were available for review. The incidences of ACP pneumatization and PR pneumatization were 23.4 and 37.5%. The mean distances from the CSP to the left optic canal midpoint, the left ACP entrance point, and the left PR lateral wall were 17.2, 15.6, and 27.6 mm, respectively. The corresponding distances from the CSP on the right side were 17.3, 15.8, and 28.0 mm, respectively. Measurements from the maxillary spine to the optic canal midpoint, ACP entrance point, and PR lateral wall on each side were performed also. Conclusion This approach provides both quantitative and qualitative understanding of sphenoid osteology and may be coupled with intraoperative surgical navigation to reduce the risks of sphenoid surgery. Both PR and ACP pneumatization are surprisingly common. Because the CSP-derived relationships may be referenced during endoscopic surgical navigation, they may provide greater clinical utility than traditional alternatives. This paradigm may facilitate a greater understanding of sphenoid anatomy and enhance surgical safety and precision.

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Martin J. Citardi

University of Texas Health Science Center at Houston

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Pete S. Batra

Rush University Medical Center

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Bit Na Yoon

Pusan National University

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Eui Kyung Goh

Pusan National University

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Kyu Sup Cho

Pusan National University

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Byung-Joo Lee

Pusan National University

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Soo Geun Wang

Pusan National University

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