Francis Renault

Impaired cortical processing of inspiratory loads in children with chronic respiratory defects

BackgroundInspiratory occlusion evoked cortical potentials (the respiratory related-evoked potentials, RREPs) bear witness of the processing of changes in respiratory mechanics by the brain. Their impairment in children having suffered near-fatal asthma supports the hypothesis that relates asthma severity with the ability of the patients to perceive respiratory changes. It is not known whether or not chronic respiratory defects are associated with an alteration in brain processing of inspiratory loads. The aim of the present study was to compare the presence, the latencies and the amplitudes of the P1, N1, P2, and N2 components of the RREPs in children with chronic lung or neuromuscular disease.MethodsRREPs were recorded in patients with stable asthma (n = 21), cystic fibrosis (n = 32), and neuromuscular disease (n = 16) and in healthy controls (n = 11).ResultsThe 4 RREP components were significantly less frequently observed in the 3 groups of patients than in the controls. Within the patient groups, the N1 and the P2 components were significantly less frequently observed in the patients with asthma (16/21 for both components) and cystic fibrosis (20/32 and 14/32) than in the patients with neuromuscular disease (15/16 and 16/16). When present, the latencies and amplitudes of the 4 components were similar in the patients and controls.ConclusionChronic ventilatory defects in children are associated with an impaired cortical processing of afferent respiratory signals.

FACIAL, LINGUAL, AND PHARYNGEAL ELECTROMYOGRAPHY IN INFANTS WITH PIERRE ROBIN SEQUENCE

Introduction: We evaluated the role of electromyography (EMG) in assessing orofacial neurological dysfunction in 81 infants with Pierre Robin sequence (PRS). Methods: Needle EMG of muscles of the face, tongue, and soft palate, and blink responses were recorded. A two‐channel EMG recorded sucking and swallowing during bottle feeding. Results: Neurogenic EMG signs were detected in facial or oral muscles in 17 of 24 associated PRS and 1 of 57 isolated PRS cases (P < 0.0001). Soft palate muscles showed low‐amplitude traces in 41.4% of patients who required two surgical steps for cleft palate repair and 18.5% of those who required only one step. Regarding EMG study during bottle feeding, patients with moderate or severe abnormalities of oral/pharyngeal coordination required more prolonged enteral feeding than patients with mild abnormalities or normal coordination (P = 0.002). Conclusion: Combined EMG methods were useful in the treatment of infants with PRS. EMG detection of cranial nerve involvement strongly suggests an associated form of PRS. Muscle Nerve, 2011

Congenital multiple cranial neuropathies: Relevance of orofacial electromyography in infants.

Introduction: The aim of this study was to assess diagnoses and outcomes of infants with 2 or more cranial neuropathies identified using orofacial electromyography (EMG). Methods: This retrospective study involved 90 patients. Diagnoses took into account clinical, radiological, and genetic data. EMG examined the orbicularis oculi, genioglossus, and levator veli palatini muscles, and blink responses. To evaluate outcome, neurological disability, respiratory complications, and feeding difficulties were recorded. Results: The patients had malformation syndromes (59), encephalopathies (29), or no underlying disorders (2). Neurogenic EMG signs were detected in a mean of 4 muscles, reflecting a mean of 3 affected nerves. EMG identified a higher number of neuropathies than clinical examination alone (82 vs. 31, facial; 56 vs. 2, pharyngeal; 25 vs. 3, hypoglossal). Poor outcome and death were more frequent when EMG identified ≥4 affected nerves (P = 0.02). Conclusion: EMG highlights multiple cranial neuropathies that can be clinically silent in infants with malformation syndromes or encephalopathies. Muscle Nerve 52: 754–758, 2015

Outcomes of Neonatal Bulbar Weakness.

BACKGROUND AND OBJECTIVE: Neonatal bulbar weakness (BW) has various etiologies and a broad prognostic range. We aimed to report outcomes in a large series of children with neonatal BW and explore the association of orofacial electrodiagnostic data with outcome. METHODS: We retrospectively reviewed the files of children who presented with facial, lingual, laryngeal, or pharyngeal weakness at birth and who underwent electrodiagnostic studies combining conventional needle electromyography (EMG) of orofacial muscles, blink responses, and EMG during bottle-feeding. Outcome measures included the need for prolonged respiratory assistance and enteral feeding, as well as sensorimotor and cognitive impairments. RESULTS: Of 175 patients, 73% had developmental disorders, 25% suffered from acquired brain damage, and 2% had no apparent underlying disorders. Motor or mental impairment was observed in 71%; death occurred in 16%. Outcomes were not significantly different when comparing developmental disorders versus acquired brain damage or neurogenic versus normal detection EMG. Abnormal blink responses were associated with higher frequencies of respiratory assistance (P = .03), gastrostomy (P = .025), and death (P = .009); moderate or severe oropharyngeal incoordinations were associated with higher frequencies of respiratory assistance (P = .006), prolonged enteral feeding (P < .0001), and gastrostomy (P = .0002). CONCLUSIONS: Orofacial electrodiagnostic studies provide supplementary information to help the pediatrician anticipate the management and prognosis of young infants with BW.

Congenital diaphragm weakness without neuromuscular disease.

We report on two children presenting at birth with respiratory failure, bilateral diaphragmatic eventration, and floppiness. Electrodiagnostic studies of the limbs, and biochemical and DNA studies excluded generalized neuromuscular diseases. Phrenic nerve electrodiagnostic studies and electromyography of the diaphragm suggested isolated diaphragm hypoplasia. Diaphragm muscle biopsy showed a paucity of muscle fibers. Isolated hypoplasia of the diaphragm is a rare cause of neonatal respiratory failure, which may have a favorable outcome with long‐term ventilatory support. Muscle Nerve, 2008

Long‐term EEG in patients with the ring chromosome 20 epilepsy syndrome

The recognizable electroencephalography (EEG) pattern of ring chromosome 20 epilepsy syndrome can be missing in patients with r(20) chromosomal anomaly, and may be found in patients with frontal lobe epilepsy of other origin. This study aims to search for more specific EEG signs by using long‐term recordings and measuring the duration of paroxysmal anomalies. The series included 12 adult patients with r(20) anomaly, and 12 controls without any chromosomal aberration. We measured the duration of every paroxysmal burst and calculated the sum of their durations for each long‐term EEG recording. We compared patients to controls using the Mann‐Whitney U‐test. Every patient showed long‐lasting paroxysmal EEG bursts, up to 60 min; controls did not show any bursts longer than 60 s (p < 0.0001). The total duration of paroxysmal anomalies was significantly longer in patients (31–692 min) compared to controls (0–48 min) (p < 0.0001). Thus, long‐term recordings enhance the contribution of EEG methods for characterizing the ring 20 chromosome epilepsy syndrome.

Correction: Impaired cortical processing of inspiratory loads in children with chronic respiratory defects

BACKGROUND Inspiratory occlusion evoked cortical potentials (the respiratory related-evoked potentials, RREPs) bear witness of the processing of changes in respiratory mechanics by the brain. Their impairment in children having suffered near-fatal asthma supports the hypothesis that relates asthma severity with the ability of the patients to perceive respiratory changes. It is not known whether or not chronic respiratory defects are associated with an alteration in brain processing of inspiratory loads. The aim of the present study was to compare the presence, the latencies and the amplitudes of the P1, N1, P2, and N2 components of the RREPs in children with chronic lung or neuromuscular disease. METHODS RREPs were recorded in patients with stable asthma (n = 21), cystic fibrosis (n = 32), and neuromuscular disease (n = 16) and in healthy controls (n = 11). RESULTS The 4 RREP components were significantly less frequently observed in the 3 groups of patients than in the controls. Within the patient groups, the N1 and the P2 components were significantly less frequently observed in the patients with asthma (16/21 for both components) and cystic fibrosis (20/32 and 14/32) than in the patients with neuromuscular disease (15/16 and 16/16). When present, the latencies and amplitudes of the 4 components were similar in the patients and controls. CONCLUSION Chronic ventilatory defects in children are associated with an impaired cortical processing of afferent respiratory signals.