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Biomedical subjects

G Roger

Publications and source records attributed to G Roger.

At least 19 recordsLinked to original sources
PubMed2001

Chronic stridor caused by laryngomalacia in children: work of breathing and effects of noninvasive ventilatory assistance.

Breathing pattern, gas exchange, and respiratory effort were assessed in five awake children with chronic stridor caused by laryngomalacia during spontaneous breathing (SB) and noninvasive mechanical ventilation (NIMV). During SB, the youngest children were able to maintain normal gas exchange at the expense of an increased work of breathing as assessed by calculated diaphragmatic pressure-time product (PTPdi), whereas the opposite was observed in the older children. NIMV increased tidal volume, from 8.77 +/- 2.04 ml/kg during SB to 11.67 +/- 2.52 ml/kg during NIMV, p = 0.04, and decreased respiratory rate, from 24.4 +/- 5.6 breaths/ min during SB to 16.6 +/- 0.9 breaths/min during NIMV, p = 0.04. NIMV unloaded the respiratory muscles as reflected by the significant reduction in PTPdi, from a mean value of 541.0 +/- 196.6 cm H(2)O x s x min(-1) during SB to 214.8 +/- 116.0 cm H(2)O x s x min(-1) during NIMV, p = 0.04. Therefore, NIMV successfully relieves the additional load imposed on the respiratory muscles. Long-term home NIMV was provided to a total of 12 children with laryngomalacia (including these five) and was associated with clinical improvement in sleep and growth.

Age Factors↗
PubMed2001

Connexin 26 gene mutations in congenitally deaf children: pitfalls for genetic counseling.

OBJECTIVE: To evaluate difficulties encountered in genetic counseling in deaf children carrying connexin 26 gene (CX26 or GJB2) mutations. DESIGN: Prospective study. SETTING: Outpatients, tertiary referral center. PATIENTS: Ninety-six unrelated deaf children in whom CX26 mutations had been detected consecutively. Children were recruited to a center for genetic counseling for deaf children, and all had congenital deafness, sporadic or familial. RESULTS: In 63 children, deafness was clearly a DFNB1 form with autosomal recessive inheritance: 47 of the 63 were homozygous for the most frequent mutation, the deletion of G at position 35 (35delG); 16 of 63 carried on both alleles of CX26 frameshift or stop mutations, or missense mutations affecting a critical region of the gene. In 33 of 96 children, genetic counseling was difficult: 21 of 33 had a single mutation detected, 11 of 33 had new missense mutations or mutations whose pathogenicity remains debated in the literature, and 1 of 33 had a genotype with both a recessive mutation (35delG) and a mutation acting as a dominant mutation. CONCLUSIONS: Interpretation of results for the molecular diagnosis of mutations in the connexin 26 gene is difficult in almost one third of cases. Close collaboration between geneticists familiar with deafness and otolaryngologists is essential to provide a high standard of genetic advice.

Adult↗
PubMed2001

[Episodic laryngeal dysfunction].

Episodic laryngeal dysfunction (ELD), also known as paradoxical vocal cord dysfunction or laryngeal dyskinesia, is characterized by abnormal closure of the vocal cords during inspiration (and sometimes at the very start of expiration). It can manifest in different ways depending on the patient's age. In the newborn, it is usually associated with stridor restricted to the inspiratory breath following crying, and the natural history is always one of rapid resolution. Occasionally, a more severe form presents with intense dyspnea and marked inspiratory stridor in a baby that usually has extensive gastroesophageal reflux which has not been treated adequately enough to improve the dyspnea or the associated vasovagal attacks. A tracheotomy may be necessary. It is rare for this disease to present between the ages of 2 and 8 years. Thereafter, it may present as a form of pseudo asthma resistant to bronchodilators and anti-inflammatory drugs. The dyspnea can be very severe and lead the family to seek hospital admission, at least during the initial episodes. There is a female preponderance. The key to making the diagnosis is the complete reversibility of the patient's symptoms when they are distracted. Exertion asthma can be mimicked by forms of ELD that occur only by effort (apart from the profile of the lung function tests). There may be significant gastroesophageal reflux. Medical intervention (hospitalization and tracheotomy) must be avoided, treatment being essentially behavioral. Finally, some cases of paradoxical adduction of the vocal cords have been described with the use of neuroleptics, brain stem compression, cortical lesions and, much more rarely, motoneuron disease. This diagnosis requires a high index of suspicion, particularly in patients with asthma whose presentation or clinical course with treatment is atypical.

Age Factors↗
PubMed2001

Abnormal central complex is a marker of severity in the presence of partial ciliary defect.

BACKGROUND: Ciliary ultrastructural defects with total lack of dynein arms (DA) cause abnormal mucociliary function leading to the chronic infections observed in primary ciliary dyskinesia. The role of partial ciliary ultrastructural defects, especially those involving the central complex, and their relationship with respiratory symptoms have been less thoroughly investigated. OBJECTIVE: In a pediatric population with partial ciliary defects, we determined the relationship(s) between ultrastructural findings, ciliary motility, and clinical and functional features, and evaluated the outcome of this population. DESIGN: We analyzed the clinical presentation and pulmonary function of 43 children with chronic bronchitis and partial ultrastructural defects (from 15% to 90%) of their respiratory cilia demonstrated on bronchial biopsies. The study population was divided into 3 groups according to ciliary ultrastructure: the main ultrastructural defect concerned the central complex in 23 patients (CC group), peripheral microtubules in 8 patients (PMT group), and DA in 12 patients (DA group). RESULTS: The percentage of ciliary defects was lower in the PMT group than in the CC and DA groups. Patients in the PMT group had less severe disease with frequent normal ciliary motility. Patients in the CC group had initially a higher incidence of respiratory tract infections, extensive bronchiectasis frequently requiring surgery, and arguments in favor of a congenital origin (high proportion of sibling form). Partial absence of DA, although of congenital origin, was associated with a good prognosis. In all groups, follow-up showed that the functional prognosis remained good with appropriate treatment. CONCLUSIONS: In children with chronic respiratory infections, presence of situs inversus, sibling form, obstructive pulmonary syndrome, or bronchiectasis required ultrastructural analysis, regardless of ciliary motility. Detection of CC abnormalities is a marker of severity and required intensive therapy and close follow-up.

Adolescent↗
PubMed2001

Tracheal dyskinesia associated with midline abnormality: embryological hypotheses and therapeutic implications.

Abnormalities of tracheal rigidity, which may lead to the collapse of the airway during expiration and consequent complications, characterize two groups of disorders: tracheomalacia (weakness of the anterior cartilaginous arc of the trachea) and tracheal dyskinesia (dysfunction of the posterior membranous trachea). Tracheal dyskinesia can either be isolated or associated with a more complex syndrome of malformations: esophageal atresia, tracheoesophageal fistula and laryngotracheal cleft. Although our knowledge of the embryological development of the tracheoesophageal axis remains limited, the existence of these associations suggests that tracheal dyskinesia is of congenital origin. The presentation of three clinical cases demonstrates that the coexistence of a midline malformation and of tracheal dyskinesia complicates the therapeutic management of the first malformation. In particular, the postoperative follow-up is often more difficult, and a long-term tracheostomy is often required (sometimes for several years). However, it must be pointed out that tracheal dyskinesia, even in the associated forms, has a good long-term prognosis, since spontaneous resolution as the child grows up is the rule.

Child, Preschool↗
PubMed2000

Audiophonological results after cochlear implantation in 40 congenitally deaf patients: preliminary results.

The aim of this study is to evaluate the prognostic factors of audiophonological results in cochlear implant in congenitally deaf patients. Between 1991 and 1996. 40 congenitally deaf children underwent cochlear implantation in our department, at an average age of 7 years (median: 5 years). The results of speech therapy were evaluated with a mean follow-up of 2 years and were classified according to four criteria: perception of sound, speech perception, speech production and the level of oral language. For each criterion, a score was established ranging from zero to four. These scores were weighted according to age such that the results before and after implantation only reflected the changes related to the implantation. The prognostic factors for good results were: a good level of oral communication before implantation, residual hearing, progressive deafness and implantation at a young age. On the other hand, poor prognostic factors were: the presence of behavioral disorders and poor communication skills prior to implantation. Overall, the major prognostic factor for a good outcome appeared to be the preoperative level of oral language, even if this was rudimentary.

Adolescent↗
PubMed2000

Extensive lymphangioma presenting with upper airway obstruction.

OBJECTIVE: To describe the results of an outcome survey of 18 cases of pediatric lymphangioma with dyspnea from encroachment on the tongue base, parapharyngeal space, and/or larynx. DESIGN: Retrospective review of files from January 1983 to September 1998. SETTING: Pediatric otolaryngology departments from 2 referral centers. PATIENTS: Eighteen patients were treated. The average age at initial surgery was 22 weeks (median, 5 weeks). All presented with at least unilateral suprahyoid and infrahyoid cavernous (microcystic) lymphangioma. The tongue base was involved in 11 patients, the parapharyngeal space in 12, and the larynx in 8. INTERVENTIONS: Neck dissection was performed initially in all patients. Tracheotomy was performed in 9 patients (50%). Macroglossia was treated by V glossoplasty. Parapharyngeal extensions were treated by cervicotomy or endoscopy, and larynx and tongue base extensions by carbon dioxide laser photocoagulation. Supraglottic laryngectomy was performed in 2 patients. MAIN OUTCOME MEASURES: Residual disease, decannulation, duration of tracheotomy, and persistent respiratory symptoms. RESULTS: The average follow-up was 4 years postoperatively. One postoperative death occurred. Sixteen (94%) of the remaining 17 patients had residual lymphangioma. Eight (89%) of the 9 patients with tracheotomy underwent decannulation (average duration, 22 months). Ten patients had persistent symptoms, and 6 were asymptomatic. CONCLUSIONS: Involvement of the upper airway seems to be the determining prognostic factor in extensive lymphangioma. Patients with dyspnea by external compression of cervical lymphangioma on the airway responded well to surgery. Aggressive surgical treatment did not seem to significantly improve the prognosis in patients with intrinsic involvement of the upper airway. The natural evolution of untreated massive lymphangioma has not been documented. Less aggressive, symptomatic therapy may be an alternative to avoid mutilating surgery in patients with intrinsic involvement of the airway.

Airway Obstruction↗
PubMed2000

Characterization of inflammatory reaction in upper airways of cystic fibrosis patients.

Inflammatory cell populations have not been yet precisely evaluated in cystic fibrosis (CF) airways. We intended to characterize morphological modifications, inflammatory cell infiltration and cell proliferation in nasal tissues obtained from 15 CF patients and from 6 non-CF patients with nasal polyposis. Morphological analysis showed an intense inflammatory infiltration in CF and non-CF tissues with only few modifications in the epithelium from CF tissues. Inflammatory cell populations characterized by specific immunolabeling were quantified, showing a predominance of macrophages and T- and B-lymphocytes and only moderate numbers of neutrophils in CF tissues; in non-CF polyps, lymphocytes and eosinophils were abundant. Proliferating cell percentages quantified after proliferating cell nuclear antigen immunolabeling were 5.3+/-4.1% (mean +/- SD) in CF polyps and 3.1+/-1.2% in non-CF polyps in epithelium but were very low in lamina propria. Intense inflammation in nasal tissues from CF patients is therefore dominated by macrophages and lymphocytes rather than by neutrophils. While morphology is preserved, proliferation is high in epithelium from CF polyps. These findings should be regarded in the future for a better understanding of inflammation in CF airway disease.

Adolescent↗
PubMed1999

Head and neck infantile myofibromatosis--a report of three cases.

Infantile myofibromatosis (IM) is a proliferative disorder characterized by the development of single or multiple nodular lesions arising from cutaneous, subcutaneous, muscular, bone or visceral structures. This proliferation may occur at any anatomical site, but in 30% of the cases it involves the head and neck. We report here three cases of head and neck IM occurring in young children and presenting as solitary lesions. The clinical heterogeneity and the misleading histopathological appearances can make the diagnosis difficult. The treatment is surgical but the low rate of recurrence and the possibility of spontaneous tumoral regression may lead to conservative surgery or therapeutic abstention.

Child↗
PubMed1999

Congenital tracheoesophageal fistula without esophageal atresia.

The authors report a series of eight cases of isolated tracheoesophageal fistula without esophageal atresia (or an H type fistula), treated in three pediatric ENT departments. This is a rare malformation whose diagnosis requires investigation for associated anomalies. The clinical signs are mainly respiratory but also digestive and the symptomatology can be severe. The diagnosis can be made with a barium swallow combined with cineradiography, but a tracheoesophageal endoscopy remains the investigation of choice. The treatment is surgical. In most cases, the fistula is accessible by a right or left cervicotomy, depending on the surgeon's practice, with a much lower postoperative morbidity as compared to a thoracotomy. The postoperative management was straightforward in most of our cases. We discuss the role of gastro-esophageal reflux with respect to postoperative morbidity as well as systematic treatment for reflux peri-operatively. The pros and cons of the various surgical approaches are also discussed.

Barium Radioisotopes↗
PubMed1999

The CHARGE association: the role of tracheotomy.

OBJECTIVES: To evaluate the need for a tracheotomy and its timing during the evolution of an association of malformations, including coloboma, heart defects, choanal atresia, developmental and growth retardation, genitourinary malformation, and ear anomalies (CHARGE association). DESIGN: Retrospective study from January 1988 through December 1997. SETTING: Four academic tertiary care centers. PATIENTS AND METHODS: Forty-five patients with CHARGE association having at least 3 cardinal malformations (growth retardation excluded) and review of the malformations and respiratory manifestations encountered. All the patients underwent endoscopic exploration on several occasions. We reviewed the nature and the timing of therapeutic interventions performed on the airway. RESULTS: Two patients died (one patient of septicemia, the other of unknown causes). Abnormalities of blood gas levels and/or sleep were found in 30 patients (67%), were responsible for cardiorespiratory arrest in 9 (20%), and required admission to the intensive care unit in 21 (47%). Pharyngolaryngeal anomalies leading to dyspnea (discoordinate pharyngolaryngomalacia, glossoptosis, retrognathia, laryngeal paralysis, cleft, stenosis, and difficult intubation) were found in 26 patients (58%). Tracheobronchial anomalies (esophagotracheal fistula, esophageal atresia, and tracheomalacia) were present in 18 patients (40%). Resection of the aryepiglottic folds was attempted 3 times, but without success. Tracheotomy was necessary in 13 patients (29%) at a median age of 2.4 months (mean duration, 25 months). Among these infants, the posterior nasal choanae were patent in 10 patients at the time of tracheotomy. Gastroesophageal reflux was encountered in 36 patients (80%). Prolonged enteral feeding was necessary in 21 patients (47%), with gastrostomy in 16 (of whom 9 needed a tracheotomy). These feeding difficulties and airway problems were highly correlated. CONCLUSIONS: We encountered multiple, complicated airway abnormalities. Resection of aryepiglottic folds was inadequate. Often, a tracheotomy could not be avoided in these patients, regardless of choanal patency. Tracheotomy needs to be performed early to avoid hypoxic events. In some selected patients, ventilation using bilevel positive airway pressure may be an alternative.

Abnormalities, Multiple↗
PubMed1999

Evolution of the bacteriologic features of persistent acute otitis media compared with acute otitis media: a 15-year study.

OBJECTIVES: To define the epidemiologic features of persistent acute otitis media (PAOM) and modifications of these features during the past 15 years and to investigate for possible differences in bacterial resistance between acute otitis media (AOM) and PAOM. DESIGN: Retrospective patient series. SETTING: Academic tertiary care center. PATIENTS AND METHODS: Persistent acute otitis media was defined as AOM lasting longer than 3 weeks despite 1 or several courses of antibiotic therapy, with the persistence of clinical and otoscopic signs of AOM. From 1982 to 1997, 475 children with PAOM were seen in our department. Every patient had 1 or several specimens of aspirations or swabs of spontaneous otorrhea (or both). Microbiologic characteristics of the isolated strains (including antibiotic susceptibility) were analyzed. Four successive series of specimens were analyzed-group 1: from October 1, 1982, to June 30, 1986 (136 patients); group 2: from January 1, 1987, to December 31, 1989 (165 patients); group 3: from January 1, 1992, to April 30, 1993 (73 patients); and group 4: from January 1, 1994, to January 31, 1997 (101 patients). During the same study periods, the bacteriologic results of patients with AOM in the same geographic region were recorded. MAIN OUTCOME MEASURES: A longitudinal comparison between the groups of patients with PAOM and a cross-comparison within each group between patients with PAOM and those with AOM. RESULTS: Obtaining repeated and multiple specimens from patients with PAOM led to a progressive decrease in the rate of sterile specimens, from 35.3% (group 1, 48 patients) to 14.9% (group 4, 15 patients) (P<.01). During this period, the prevalence of Streptococcus pneumoniae increased in patients with positive culture results, from 18.2% (group 1, 16 of 88 patients) to 44.2% (group 4, 38 of 86 patients) (P<.001). These strains rapidly and dramatically became resistant to penicillin (amoxicillin) (0% through 1989, 76.2% [16 of 21 patients] in 1993, and 97.4% [37 of 38 patients] in 1996) (P = .01). The overall prevalence of Haemophilus influenzae remained stable (between 31.4% [27 of 86 patients] and 45.4% [40 of 88 patients]), but the proportion of beta-lactamase-producing strains increased from 30.0% (group 1, 12 patients) to 55.6% (group 4, 15 patients) (P=.04). The prevalences of Pseudomonas aeruginosa and Staphylococcus aureus did not vary significantly (from 23.1% [group 2, 30 patients] to 10.7% [group 3, 6 patients] and from 10.2% [group 1, 9 patients] to 4.6% [group 4, 4 patients], respectively). Comparing data from patients with PAOM with those with AOM revealed that the increased resistance of H influenzae and, in particular, of S pneumoniae was more rapid and more marked in patients with PAOM than in those with AOM (highest rate of resistance in AOM: 36.0% [271 of 753 specimens] and 50.6% [398 of 787 specimens] for H influenzae and S pneumoniae, respectively; P<.001 for S pneumoniae). CONCLUSIONS: The increase in bacterial resistance frequently encountered during otitis media is even more marked in patients with PAOM. The identification of the organism is essential when the otitis does not resolve, especially in patients with PAOM. Obtaining repeated specimens helps to decrease the rate of sterile cultures.

Acute Disease↗
PubMed1999

EPR spectroscopy: a powerful technique for the structural and functional investigation of metalloproteins.

Numerous metal centers in proteins can be prepared in a redox state in which their ground state is paramagnetic. Complementary data provided by EPR, Mössbauer, electron nuclear double resonance, magnetic circular dichroism, and NMR spectroscopies have therefore played a major role in the elucidation of the structure and function of these centers. Among those techniques the most commonly used is certainly EPR spectroscopy. In this article various aspects of the current applications of EPR to the structural and functional study of metalloproteins are presented. They are illustrated by recent studies carried out in our laboratory in the field of metalloenzymes and electron transfer systems. The power of numerical simulation techniques is emphasized throughout this work.

Agaricales↗
PubMed1999

Loss-of-function mutations in a human gene related to Chlamydomonas reinhardtii dynein IC78 result in primary ciliary dyskinesia.

Primary ciliary dyskinesia (PCD) is a group of heterogeneous disorders of unknown origin, usually inherited as an autosomal recessive trait. Its phenotype is characterized by axonemal abnormalities of respiratory cilia and sperm tails leading to bronchiectasis and sinusitis, which are sometimes associated with situs inversus (Kartagener syndrome) and male sterility. The main ciliary defect in PCD is an absence of dynein arms. We have isolated the first gene involved in PCD, using a candidate-gene approach developed on the basis of documented abnormalities of immotile strains of Chlamydomonas reinhardtii, which carry axonemal ultrastructural defects reminiscent of PCD. Taking advantage of the evolutionary conservation of genes encoding axonemal proteins, we have isolated a human sequence (DNAI1) related to IC78, a C. reinhardtii gene encoding a dynein intermediate chain in which mutations are associated with the absence of outer dynein arms. DNAI1 is highly expressed in trachea and testis and is composed of 20 exons located at 9p13-p21. Two loss-of-function mutations of DNAI1 have been identified in a patient with PCD characterized by immotile respiratory cilia lacking outer dynein arms. In addition, we excluded linkage between this gene and similar PCD phenotypes in five other affected families, providing a clear demonstration of locus heterogeneity. These data reveal the critical role of DNAI1 in the development of human axonemal structures and open up new means for identification of additional genes involved in related developmental defects.

Amino Acid Sequence↗
PubMed1999

Myringoplasty in children: predictive factors of outcome.

OBJECTIVES: To assess the results of myringoplasty in children and to determine which factors independently influence the postoperative results. STUDY DESIGN: Retrospective study of the anatomic and functional results of 231 consecutive myringoplasties performed in 188 children between 1988 and 1992. Multivariate analysis of poor prognostic factors by cross-sectional comparison 1 year after surgery. METHODS: Myringoplasties were performed via an endaural approach with a fascia temporalis underlay graft. RESULTS: In 216 of 231 ears (93.5%) the tympanic membrane was closed. A good anatomic outcome was considered to have been achieved in 188 ears (81.6%), although in 18 ears (7.8%) seromucous otitis media occurred, in 8 ears (3.5%) a progressive retraction pocket was encountered, and in 2 ears significant lateralization was present. One hundred thirty-nine (67.5%) of the 206 ears tested in the postoperative period had a postoperative air-bone gap of 10 dB or less. On average, mean bone conduction remained unaltered. The age of the patient and the size and the location of the perforation did not affect the outcome. Three prognostic factors for an abnormal postoperative tympanic membrane were found, with 95% confidence intervals: inflammatory changes in the middle ear mucosa (P < .05), contralateral tympanic perforation (P < .05), and contralateral cholesteatoma (P < .01). CONCLUSIONS: Myringoplasty with underlay grafting of the fascia temporalis in children gives good anatomic and functional results. Inflammatory changes within the middle ear mucosa, contralateral tympanic perforation, and contralateral cholesteatoma independently influence the risk of an abnormal postoperative tympanic membrane. The presence of one of these factors preoperatively should lead to the consideration of alternative, more durable graft material, such as autologous cartilage.

Adolescent↗
PubMed1999

Surgical removal of subglottic hemangiomas in children.

OBJECTIVE: To examine the indications and the results of surgical excision of severe subglottic hemangiomas. DESIGN: Retrospective study and case series. SETTING: Four academic tertiary care centers of pediatric otolaryngology. PATIENTS: Twenty children were included from 1991 to 1997. All presented with severe subglottic hemangiomas resistant to classical treatments such as corticosteroids and/or CO2 laser. INTERVENTION: Six children were operated on using laryngotracheal reconstruction and prolonged stenting by a reinforced Silastic roll and 14 children were operated on by a single-stage laryngotracheoplasty and postoperative intubation in a pediatric intensive care unit. RESULTS: All patients were successfully decannulated or extubated and have been free from recurrent hemangiomas. CONCLUSION: The surgery of severe subglottic hemangiomas is a reliable technique in selected patients and should be considered in corticoresistant or corticodependent, circular, or bilateral hemangiomas.

Child, Preschool↗
PubMed1998

Pharyngo-laryngeal histoplasmosis: one case in an immunocompetent child.

We report a very rare case of disseminated pharyngo-laryngeal histoplasmosis with systemic spread in a 10-year-old, immunocompetent child from Guyana. The main signs were a marked deterioration in his general condition, hepato-splenomegaly, multiple lymphadenopathy and ulcerated pharyngo-laryngeal lesions. The diagnosis was made from brushings of the ulcerative lesions, a lymph node biopsy and serological tests performed in the national reference center for histoplasmosis. The initial treatment was with amphotericin B, which was then replaced by oral itraconazole. We report here the main epidemiological, clinical and therapeutic characteristics.

Amphotericin B↗