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Dive into the research topics where Gresham T. Richter is active.

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Featured researches published by Gresham T. Richter.


Laryngoscope | 2010

Propranolol for infantile hemangiomas: Early experience at a tertiary vascular anomalies center

Lisa M. Buckmiller; Patrick D. Munson; Umesh Dyamenahalli; Yuemeng Dai; Gresham T. Richter

Propranolol has recently been introduced as a novel pharmacologic treatment for infantile hemangiomas. Systematic examination of this treatment in a tertiary care setting has not been described. This study explores the impact of propranolol on both proliferative and involuting hemangiomas at a tertiary vascular anomalies center.


Oral Diseases | 2010

Diagnosis and management of hemangiomas and vascular malformations of the head and neck

Lisa M. Buckmiller; Gresham T. Richter; James Y. Suen

Vascular anomalies are congenital errors in vascular development. They frequently involve the head, neck, and oral cavity. Subdivided into vascular tumors (hemangiomas) and vascular malformations, vascular anomalies remain poorly understood. However, growing interest and recent advances in the diagnosis, management, and molecular characterization of these lesions are improving treatment strategies. The role of the multidisciplinary team cannot be overstated. This review provides both basic and up-to-date knowledge on the most common vascular anomalies encountered by physicians and practitioners. Because treatment options for vascular anomalies are widely variable and often debated, this report aims to provide a comprehensive approach to these lesions based upon current concepts and practical clinical experience.


International Journal of Pediatrics | 2012

Hemangiomas and Vascular Malformations: Current Theory and Management

Gresham T. Richter; Adva B. Friedman

Vascular anomalies are a heterogeneous group of congenital blood vessel disorders more typically referred to as birthmarks. Subcategorized into vascular tumors and malformations, each anomaly is characterized by specific morphology, pathophysiology, clinical behavior, and management approach. Hemangiomas are the most common vascular tumor. Lymphatic, capillary, venous, and arteriovenous malformations make up the majority of vascular malformations. This paper reviews current theory and practice in the etiology, diagnosis, and treatment of these more common vascular anomalies.


Laryngoscope | 2009

Propranolol for Airway Hemangiomas: Case Report of Novel Treatment

Lisa M. Buckmiller; Umesh Dyamenahalli; Gresham T. Richter

Infantile hemangiomas arising in the trachea are rare. These lesions pose a management dilemma as several treatment options can provide safe management. Propranolol, a nonselective beta‐blocker, has recently been introduced as a novel modality for the treatment of proliferating hemangiomas. This report illustrates the successful management of tracheal hemangiomas using oral propranolol in a young patient with otherwise treatment‐resistant airway lesions. Despite various endoscopic therapeutic attempts, the patient remained stridulous with airway disease that persisted into the involution phase of the average hemangioma cycle. Within 6 weeks of beginning oral propranolol (2 mg/kg/day), her airway compromise was eliminated and she had complete resolution of endoscopically visible disease. No side effects from propranolol occurred. We propose that oral propranolol should be considered for use in airway hemangiomas. Laryngoscope, 2009


Journal of Clinical Investigation | 1998

Role of inducible nitric oxide synthase in regulation of pulmonary vascular tone in the late gestation ovine fetus.

Robyn L. Rairigh; T. D. Le Cras; D. Dunbar Ivy; J. P. Kinsella; Gresham T. Richter; Marilee P Horan; I D Fan; S. H. Abman

Nitric oxide (NO) produced by NO synthase (NOS) modulates fetal pulmonary vascular tone and contributes to the fall in pulmonary vascular resistance (PVR) at birth. Although the inducible (type II) NOS isoform is present in human and rat fetal lungs, it is uncertain whether type II NOS activity contributes to vascular NO production in the fetal lung. To determine whether type II NOS is present in the ovine fetal lung and to study the potential contribution of type II NOS on the regulation of basal PVR in the fetus, we measured the hemodynamic effects of three selective type II NOS antagonists: aminoguanidine (AG), 2-amino-5,6-dihydro-6-methyl-4H-1,3 thiazine (AMT), and S-ethylisothiourea (EIT). Studies were performed after at least 72 h of recovery from surgery in 19 chronically prepared fetal lambs (133+/-3 d; 147 d, term). Brief intrapulmonary infusions of AG (140 mg), AMT (0.12 mg), and EIT (0.12 mg) increased basal PVR by 82, 69, and 77%, respectively (P < 0.05). The maximum increase in PVR occurred within 20 min, but often persisted up to 80 min. These agents also increased mean aortic pressure but did not alter the pressure gradient between the pulmonary artery and aorta, suggesting little effect on tone of the ductus arteriosus. Acetylcholine-induced pulmonary vasodilation remained intact after treatment with selective type II NOS antagonists, but not after treatment with the nonselective NOS blocker, nitro-L-arginine. Using Northern blot analysis with poly(A)+ RNA, we demonstrated the presence of two mRNA transcripts for type II NOS (4.1 and 2.6 kb) in the fetal lung. We conclude that the type II NOS isoform is present in the ovine fetal lung, and that selective type II NOS antagonists increase PVR and systemic arterial pressure in the late-gestation fetus. We speculate that type II NOS may play a physiological role in the modulation of vascular tone in the developing fetal lung.


European Archives of Oto-rhino-laryngology | 2009

Update on hemangiomas and vascular malformations of the head and neck.

Behfar Eivazi; Mircia Ardelean; Wolfgang Bäumler; Hans-Peter Berlien; Hansjörg Cremer; Ravindhra G. Elluru; Peter J. Koltai; Jan Olofsson; Gresham T. Richter; Bernhard Schick; Jochen A. Werner

Although the current classification systems of vascular malformations and hemangiomas are increasingly accepted, there are nonetheless several aspects that show us how special and at the same time difficult it is to diagnose, evaluate, and treat some of those diseases. Close interdisciplinary cooperation of all involved disciplines is essential; the discussion of the adequate individual procedure must be performed in angioma boards, as it is already well established in the context of tumor boards. The interface of angioma therapy and tumor therapy seems to be very close, which is certainly true for the aspect of angiogenesis and of course for the inhibited proliferation as promising therapeutic approach of complex vascular malformations. This leads to another obvious necessity of intensifying experimental scientific research on vascular malformations and hemangiomas, which is a precondition for optimizing or elimination of different current problems and deficits in the mentioned field.


Journal of Pediatric Surgery | 2008

Endoscopic management of recurrent tracheoesophageal fistula

Gresham T. Richter; Frederick C. Ryckman; Rebeccah L. Brown; Michael J. Rutter

RATIONALE Recurrent tracheoesophageal fistulas (RTEFs) remain a therapeutic challenge because open surgical approaches have been associated with substantial rates of morbidity, mortality, and repeat recurrences. Recently, endoscopic techniques for the repair of RTEF have provided an alternative approach with the potential for improved surgical outcomes. However, previous reports have been limited by small patient numbers and variations in technique. By examining a single institutions experience and performing a systematic review of previously published results, we aimed to identify an optimal approach to managing RTEF endoscopically. METHODS Retrospective chart review of patients undergoing endoscopic management of RTEF at a single tertiary care institution was performed. Medline search and summated analysis of previously published cases of endoscopically treated RTEF from 1975 to 2007 was conducted. RESULTS Four patients with RTEF were identified and selected for endoscopic repair at our institution from 2003 to 2007 (mean age, 11.5 months). Under endoscopic guidance, fistula tracts were de-epithelialized with a Bugbee fulgurating diathermy electrode (5-15 W) and then sealed with fibrin glue (Tisseel with added aprotinin). Closure of RTEF was successful in 3 patients after a single attempt. One revision was required after inadvertent recannulation of the tract with an emergent tracheostomy tube change. No patient has evidence of recurrence (mean follow-up, 16 months). In 15 articles of endoscopically repaired RTEF, 37 cases have been reported from 1975 until present. In general, 3 approaches to endoscopic repair have been explored. Analysis of all reported cases in the literature and results from our patient series suggests that endoscopic techniques designed to both de-epithelialize the fistula tract and seal with fibrin glue have the best chance for cure after a single attempt. Patients with long, thin, and small diameter fistula who have enough distal trachea to accommodate a postoperative cuffed ventilating tube beyond the fistula are ideal candidates for endoscopic repair. CONCLUSION In select patients, endoscopic management of RTEF using Bugbee cautery and tissue adhesives can reduce morbidity and recurrence associated with open approaches and alternative endoscopic techniques.


Archives of Otolaryngology-head & Neck Surgery | 2008

Late-Onset Laryngomalacia: A Variant of Disease

Gresham T. Richter; Michael J. Rutter; Alessandro deAlarcon; Laura J. Orvidas; Dana Thompson

OBJECTIVE To identify and describe the features of laryngomalacia (LM) in a cohort of older children, with the goal of providing an approach to diagnosis and management of these patients. Laryngomalacia is a common congenital disorder characterized by decreased laryngeal tone, supraglottic collapse, and stridor during inspiration and is rarely seen in older children. However, the presence of LM in this population may be obscured by related but uncommon clinical features. DESIGN Prospective collection and retrospective evaluation of older children with evidence of LM from 1998 to 2005. SETTING Two tertiary pediatric institutions. PATIENTS Prospective data collection of 239 patients with LM, including 222 with congenital LM and 17 diagnosed as having LM when they were older than 2 years and without a medical history of prior disease or symptoms-late-onset LM (mean age at onset, 6.6 years). INTERVENTION Supraglottoplasty. MAIN OUTCOME MEASURE Symptom improvement. RESULTS Patients with late-onset LM were classified into 3 categories according to their symptom complex; those presenting with feeding-disordered LM (n = 7; mean age at onset, 3.3 years), sleep-disordered LM (n = 7; mean age at onset, 6.3 years), and exercise-induced LM (n = 3; mean age at onset, 15 years). Stridor was rarely present except in patients with exercise-induced LM during strenuous activity. Profound arytenoid redundancy and prolapse was discovered in all patients during nasolaryngeal endoscopy. Typical anatomic features of congenital LM (shortened aryepiglottic folds or retroflexed epiglottis) were not discovered. No patient had a history of neuromuscular disease. Supra-arytenoid reduction (supraglottoplasty) led to clinical cure in all patients (mean duration of follow-up, 7.4 months). Prior adenotonsillectomies were performed in 5 patients with sleep-disordered LM. This did not improve symptoms, and these patients displayed evidence of LM as the source of obstruction. CONCLUSIONS Physicians should consider late-onset LM as a potential cause of feeding difficulties in toddlers, sleep apnea in children, and exercise intolerance in teenagers. As in infants with LM, supraglottoplasty improves late-onset disease.


Annals of Otology, Rhinology, and Laryngology | 2009

Secondary airway lesions in infants with laryngomalacia.

J. Matthew Dickson; Gresham T. Richter; Jareen Meinzen-Derr; Michael J. Rutter; Dana M. Thompson

Objectives: We sought to determine the incidence of secondary airway lesions in infants with laryngomalacia and to compare the incidences of these concomitant airway lesions in infants with severe, moderate, and mild laryngomalacia; to determine whether infants with mild or moderate laryngomalacia have a higher incidence of surgical intervention when a secondary airway lesion is present; and to determine whether the incidence of gastroesophageal reflux disease (GERD) is affected by the presence of a secondary airway lesion. Methods: We performed a retrospective review of a database consisting of 201 infants with a diagnosis of laryngomalacia treated at a pediatric tertiary referral center between June 1998 and June 2003. Data pertaining to demographic information, severity of laryngomalacia, presence of secondary airway lesions, and diagnosis of GERD were collected and analyzed. Results: Of the 201 infants, 104 (51.7%) were found to have a secondary airway lesion. Subglottic stenosis was found in 38.8%, and tracheomalacia in 37.8%. Of the infants with severe laryngomalacia, 30 (79%) had a diagnosis of a secondary lesion, compared with 51 (61.5%) of those with moderate and 23 (28.8%) of those with mild disease. Among infants with mild or moderate disease, those with secondary airway lesions were more likely to require surgical intervention than were infants without secondary airway lesions (27% versus 5.6%; p = 0.0002). There was no difference in the rates of secondary airway lesions in infants managed with supraglottoplasty versus tracheotomy. The incidence of GERD in this patient population was 65.6%. Infants with a secondary airway lesion were more likely to have GERD than were those without a secondary airway lesion (84.6% versus 45.4%; p < 0.0001). Conclusions: The incidence of secondary airway lesions in our population of infants with laryngomalacia was higher than those previously reported. The severity of disease correlated with the diagnosis of a secondary airway lesion. Secondary airway lesions lead to an increased incidence of surgical intervention and GERD in infants with laryngomalacia.


Annals of Otology, Rhinology, and Laryngology | 2009

Impact of supraglottoplasty on aspiration in severe laryngomalacia

Gresham T. Richter; Christopher T. Wootten; Michael J. Rutter; Dana M. Thompson

Objectives: We examined the incidence and significance of aspiration in infants with severe laryngomalacia (LM) who undergo supraglottoplasty. Methods: We performed a 5-year retrospective review of a prospective database from 2 tertiary care pediatric institutions. The studied patients were 50 consecutive infants with severe LM who underwent supraglottoplasty (median age, 4.5 months) and functional endoscopic evaluation of swallowing (FEES) with or without laryngopharyngeal stimulation testing. The intervention was cold-knife microlaryngeal supraglottoplasty and reflux management. The main outcome measure was aspiration resolution. Results: Preoperative FEES identified laryngeal penetration in 44 infants (88%) with severe LM. Laryngeal penetration with aspiration beyond the vocal folds was noted in 36 infants (72%). Postoperative FEES (median follow-up, 3.8 months) indicated resolution of laryngeal penetration and aspiration in 36 (81.8%) and 31 (86.1%) of these patients, respectively. The 14 patients without preoperative aspiration showed no evidence of aspiration after supraglottoplasty. In patients with aspiration, the mean preoperative laryngopharyngeal stimulation test threshold was 8.45 mm Hg. This improved on average by 4.0 mm Hg after supraglottoplasty (paired t-test, p < 0.0001). Multiple medical comorbidities were present in the 5 patients who had persistent aspiration after supraglottoplasty, including congenital heart disease (all 5 patients), congenital syndromes (4 patients), neurologic disorders (2 patients), and a need for tracheostomy (2 patients). Conclusions: Laryngeal penetration and aspiration improve after cold-knife supraglottoplasty. Supraglottoplasty does not cause aspiration in patients who do not have preoperative aspiration. Supraglottoplasty may not improve aspiration in patients with multiple medical comorbidities.

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James Y. Suen

University of Arkansas for Medical Sciences

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Charles M. Bower

University of Arkansas for Medical Sciences

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Lisa M. Buckmiller

University of Arkansas for Medical Sciences

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Yuemeng Dai

University of Arkansas for Medical Sciences

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Chun-Yang Fan

University of Arkansas for Medical Sciences

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John L. Dornhoffer

University of Arkansas for Medical Sciences

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Michael J. Rutter

Cincinnati Children's Hospital Medical Center

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Ali G. Saad

University of Arkansas for Medical Sciences

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Larry D. Hartzell

University of Arkansas for Medical Sciences

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Abby R. Nolder

University of Arkansas for Medical Sciences

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