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Dive into the research topics where James M. Ridgway is active.

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Featured researches published by James M. Ridgway.


Laryngoscope | 2005

In Vivo Optical Coherence Tomography of the Human Larynx: Normative and Benign Pathology in 82 Patients

Brian J. F. Wong; Ryan P. Jackson; Shuguang Guo; James M. Ridgway; Usama Mahmood; Jianping Su; Terry Y. Shibuya; Roger L. Crumley; Mai Gu; William B. Armstrong; Zhongping Chen

Objectives: Optical coherence tomography (OCT) is an emerging imaging modality that combines low‐coherence light with interferometry to produce cross‐sectional images of tissue with resolution about 10 μm. Patients undergoing surgical head and neck endoscopy were examined using a fiberoptic OCT imaging probe to study and characterize microstructural anatomy and features of the larynx and benign laryngeal pathology in vivo.


Laryngoscope | 2006

Optical coherence tomography of laryngeal cancer.

William B. Armstrong; James M. Ridgway; David E. Vokes; Shuguang Guo; Jorge Perez; Ryan P. Jackson; Mai Gu; Jianping Su; Roger L. Crumley; Terry Y. Shibuya; Usama Mahmood; Zhongping Chen; Brian J. F. Wong

Objectives: Optical coherence tomography (OCT) is a high‐resolution optical imaging technique that produces cross‐sectional images of living tissues using light in a manner similar to ultrasound. This prospective study evaluated the ability of OCT to identify the characteristics of laryngeal cancer and measure changes in the basement membrane, tissue microstructure, and the transition zone at the edge of tumors.


American Journal of Otolaryngology | 2010

Lemierre syndrome: a pediatric case series and review of literature.

James M. Ridgway; Dhavan A. Parikh; Ryan Wright; Paul K. Holden; William B. Armstrong; Felizardo Camilon; Brian J. F. Wong

BACKGROUND Lemierre syndrome is a rare disease of the head and neck often affecting adolescents and young adults. Classically, infection begins in the oropharynx with thrombosis of the tonsillar veins followed by involvement of the parapharyngeal space and the internal jugular vein. Septicemia and pulmonary lesions develop as infection spreads via septic emboli. Although a rare entity in modern times, Lemierre syndrome remains a disease of considerable morbidity and potential mortality. METHODS This was a retrospective review of 3 cases and associated literature. RESULTS A common 1- to 2-week history of fever, sore throat, neck pain, and fatigue was observed in all patients. Patient 1 developed right facial swelling, neck tenderness, trismus, and tonsillar exudate. Patient 2 displayed right tonsillar erythema and enlargement with right neck tenderness. Patient 3 revealed bilateral tonsillar enlargement with exudate and left neck tenderness. Subsequent studies included blood cultures and computed tomography, after which empiric antibiotic therapy was started. Patient 1 underwent drainage of a right peritonsillar abscess, right pressure equalization tube placement, and ligation of the right external jugular vein. He subsequently developed subdural empyemas, cavernous sinus thrombosis, and carotid artery narrowing and required 9 weeks of antibiotic therapy. Patients 2 and 3 developed pulmonary lesions and received 6 weeks of antibiotic therapy. Timing was crucial in all cases. CONCLUSIONS Lemierre syndrome is a rare but severe opportunistic infection with poor prognostic outcomes if left untreated. Early diagnosis and treatment is essential. Aggressive antibiotic therapy coupled with surgical intervention, when necessary, provides excellent outcomes.


Laryngoscope | 2007

Imaging of the Pediatric Airway Using Optical Coherence Tomography

James M. Ridgway; Gurpreet S. Ahuja; Shuguang Guo; Jianping Su; Usama Mahmood; Zhongping Chen; Brian J. F. Wong

Objectives: Optical coherence tomography (OCT) is an imaging modality that uses a broadband light source to produce high‐resolution cross‐sectional images in living tissue (8–20 μm). A prospective study of normal, benign, and pathologic tissues in the pediatric airway was conducted to assess the utility of OCT technology in characterizing the microanatomy of the pediatric upper aerodigestive tract in vivo.


Otology & Neurotology | 2008

Imaging the Human Tympanic Membrane Using Optical Coherence Tomography In Vivo

Hamid R. Djalilian; James M. Ridgway; Majestic Tam; Ali Sepehr; Zhongping Chen; Brian J. F. Wong

Objective: Optical coherence tomography (OCT) is a diagnostic imaging modality that combines low coherence light with interferometry to produce high-resolution cross-sectional images of living tissues. Using this technology, we have imaged in vivo the human tympanic membrane (TM) in the office clinic setting and characterized TM microstructure in normal and pathologic conditions. Study Design: Prospective clinical trial. Materials and Methods: The normal and diseased TMs in 10 adult subjects were examined. Each subject underwent direct microscopic examination before OCT imaging to provide visual coregistration of associated subsites including the anulus fibrosus, pars tensa, pars flaccida, and umbo. The probe from the imaging system (1,310-nm central wavelength, 15-&mgr;m coherence length, Niris; Imalux, Cleveland, OH, USA) was introduced into the ear canal to obtain lateral cross-sectional images. Results: Systematic imaging of the TM was performed with characterization of the epithelial and collagenous layers. The overall TM thickness was clearly demonstrated and quantified. Conclusion: The ability to noninvasively study middle ear microstructures in vivo is essential in the treatment of diseases of the ear. OCT may provide the otologist/neurotologist with the ability to 1) image pathology such as cholesteatoma, dimeric TMs, and chronic otitis media; 2) gauge the response to pharmacological therapy; and 3) monitor postsurgical changes after tympanoplasty and other procedures. OCT may provide a means to optimize the diagnosis and management of patients with middle ear disease.


Annals of Otology, Rhinology, and Laryngology | 2008

Optical coherence tomography-enhanced microlaryngoscopy: preliminary report of a noncontact optical coherence tomography system integrated with a surgical microscope.

David E. Vokes; Ryan P. Jackson; Shuguang Guo; Jorge Perez; Jianping Su; James M. Ridgway; William B. Armstrong; Zhongping Chen; Brian J. F. Wong

Objectives: Optical coherence tomography (OCT) is a new imaging modality that uses near-infrared light to produce cross-sectional images of tissue with a resolution approaching that of light microscopy. We have previously reported use of OCT imaging of the vocal folds (VFs) during direct laryngoscopy with a probe held in contact or near-contact with the VFs. This aim of this study was to develop and evaluate a novel OCT system integrated with a surgical microscope to allow hands-free OCT imaging of the VFs, which could be performed simultaneously with microscopic visualization. Methods: We performed a prospective evaluation of a new method of acquiring OCT images of the VFs. Results: An OCT system was successfully integrated with a surgical microscope to permit noncontact OCT imaging of the VFs of 10 patients. With this novel device we were able to identify VF epithelium and lamina propria; however, the resolution was reduced compared to that achieved with the standard contact or near-contact OCT. Conclusions: Optical coherence tomography is able to produce high-resolution images of vocal fold mucosa to a maximum depth of 1.6 mm. It may be used in the diagnosis of VF lesions, particularly early squamous cell carcinoma, in which OCT can show disruption of the basement membrane. Mounting the OCT device directly onto the operating microscope allows hands-free noncontact OCT imaging and simultaneous conventional microscopic visualization of the VFs. However, the lateral resolution of the OCT microscope system is 50 μm, in contrast to the conventional handheld probe system (10 μm). Although such images at this resolution are still useful clinically, improved resolution would enhance the systems performance, potentially enabling real-time OCT-guided microsurgery of the larynx.


American Journal of Rhinology | 2006

In vivo optical coherence tomography of the nasal mucosa.

Usama Mahmood; James M. Ridgway; Ryan P. Jackson; Shuguang Guo; Jianping Su; William B. Armstrong; Terry Y. Shibuya; Roger L. Crumley; Zhongping Chen; Brian J. F. Wong

Background Optical coherence tomography (OCT) is an emerging imaging modality that uses light to produce in vivo high-resolution cross-sectional images (7 μm) of tissues to depths of up to 3 mm. OCT is analogous to ultrasound, but relies on interferometry and low-coherence optical sources to produce images of tissue structure at the histological level. Methods In this study, OCT was used to image the mucosa overlying structures in the nasal cavity to obtain information regarding normative in vivo tissue microstructure. An OCT system using a Michaelson interferometer and a 1.3-μm broadband light source was incorporated into a fiber-optic imaging device that was inserted into the nasal cavity. Cross-sectional tomographic images of the anterior and posterior nasal septum, turbinates, and vestibule were acquired in 44 patients in either the office or the operating room during surgical endoscopy. Results OCT images of the nasal mucosa identified the distinct boundaries between the epithelium, lamina propria, and underlying bone/cartilaginous tissue. Within the lamina propria, features consistent with glands, ducts, and blood vessels were clearly identified. In patients who underwent decongestant therapy, before and after images showed distinct morphological changes in the mucosa. The thickness of the epithelium was tabulated, as well. Conclusion This study establishes the potential of using OCT to produce high-resolution images of the nasal mucosa. As an in vivo tissue microstructural imaging modality, OCT may be valuable in studying the impact of allergic and infectious disease on the nasal mucosa and monitoring its response to pharmacologic therapy.


Clinical Otolaryngology | 2009

Laryngeal epithelial thickness: a comparison between optical coherence tomography and histology

M.L. Kaiser; Marc Rubinstein; David E. Vokes; James M. Ridgway; Shuguang Guo; Mai Gu; Roger L. Crumley; William B. Armstrong; Zhongping Chen; Brian J. F. Wong

Objectives:  Optical coherence tomography, an imaging modality using near‐infrared light, produces cross‐sectional tissue images with a lateral pixel resolution of 10 μm. However, normative data is first needed on epithelial thickness for lesion characterisation, and, to date, little exists. The purpose of our study is to measure normal laryngeal epithelial thickness by in vivo optical coherence tomography, and compare these values to those obtained from fixed ex‐vivo laryngectomy specimens.


Journal of Biomedical Optics | 2009

Gradient-index lens rod based probe for office-based optical coherence tomography of the human larynx.

Shuguang Guo; Lingfeng Yu; Ali Sepehr; Jorge Perez; Jianping Su; James M. Ridgway; David E. Vokes; Brian J. F. Wong; Zhongping Chen

Optical coherence tomography (OCT) is an evolving noninvasive imaging modality that has been used to image the human larynx during surgical endoscopy. The design of a long gradient-index lens-based probe capable of capturing images of the human larynx by use of spectral domain OCT during a typical office-based laryngoscopy examination is presented. An optical-ballast-based 4f optical relay system is proposed to realize variable working distance with a constant optical delay. In-vivo OCT imaging of the human larynx is demonstrated. Office-based OCT is a promising imaging modality for early laryngeal cancer diagnosis.


Journal of Plastic Reconstructive and Aesthetic Surgery | 2014

Calcium hydroxylapatite associated soft tissue necrosis: A case report and treatment guideline

Lauren Tracy; James M. Ridgway; J. Stuart Nelson; Nelson Lowe; Brian J. F. Wong

We present an uncommon case of nasal alar and facial necrosis following calcium hydroxylapatite filler injection performed elsewhere without direct physician supervision. The patient developed severe full-thickness necrosis of cheek and nasal alar skin 24 h after injections into the melolabial folds. Management prior to referral included oral antibiotics, prednisone taper, and referral to a dermatologist (day 3) who prescribed valacyclovir for a presumptive herpes zoster reactivation induced by the injection. Referral to our institution was made on day 11, and after herpetic outbreak was ruled out by a negative Tzanck smear, debridement with aggressive local wound care was initiated. After re-epithelialization and the fashioning of a custom intranasal stent to prevent vestibular stenosis, pulsed dye laser therapy was performed for wound modification. The patient healed with an acceptable cosmetic outcome. This report underscores the importance of facial vasculature anatomy, injection techniques, and identification of adverse events when using fillers. A current treatment paradigm for such events is also presented.

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Shuguang Guo

University of California

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Jianping Su

University of California

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Zhongping Chen

University of California

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Usama Mahmood

University of Texas MD Anderson Cancer Center

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David E. Vokes

University of California

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