Neuro-vestibular correlates in cerebral hemispheric lesions

Vestibular evaluation by ENG in two patients with prior temporoparietal lesions showed abnormalities mainly with eye-tracking and optokinetic tests. Our study indicates that the optokinetic test is easy to perform and has a greater diagnostic significance than the other tests as to the site of lesion.     

Perception of the acoustic environment and neuroimaging findings: a report of six cases with a history of closed head injury

Conclusion: The main finding was the relation between difficulty in determining the direction of movement of a sound source and frontal lesions and poor working memory. Poor correspondence in some cases between functional findings and imaging findings can be due to the possibility of axonal degeneration as well as plastic reorganization. Objective: The purpose of the present investigation of six cases was to identify auditory, cognitive and neuroimaging long-term sequelae of closed head injury (CHI) with particular focus on environmental sound recognition and moving sound sources. Subjects and methods: Six subjects who had experienced CHI were investigated with auditory tests. Four subjects also completed cognitive testing. CT and MRI were performed. Results: There was a large individual variability of the test results with respect to morphological findings. In five cases with central auditory processing disorders morphological brain damage was demonstrated. Two cases with shortcomings on cognitive testing and with frontal brain lesions demonstrated problems in determining the direction of movement of a sound source. The results may indicate that basal frontal lobe structures play a role in following and determining the direction of movement of a sound source. Two cases had problems with environmental sound recognition; in one left temporal brain lesions were demonstrated.     

Childhood apraxia of speech and multiple phonological disorders in Cairo-Egyptian Arabic speaking children: Language, speech, and oro-motor differences

Childhood apraxia of speech is a neurological childhood speech-sound disorder in which the precision and consistency of movements underlying speech are impaired in the absence of neuromuscular deficits. Children with childhood apraxia of speech and those with multiple phonological disorder share some common phonological errors that can be misleading in diagnosis. This study posed a question about a possible significant difference in language, speech and non-speech oral performances between children with childhood apraxia of speech, multiple phonological disorder and normal children that can be used for a differential diagnostic purpose. 30 pre-school children between the ages of 4 and 6 years served as participants. Each of these children represented one of 3 possible subject-groups: Group 1: multiple phonological disorder; Group 2: suspected cases of childhood apraxia of speech; Group 3: control group with no communication disorder. Assessment procedures included: parent interviews; testing of non-speech oral motor skills and testing of speech skills. Data showed that children with suspected childhood apraxia of speech showed significantly lower language score only in their expressive abilities. Non-speech tasks did not identify significant differences between childhood apraxia of speech and multiple phonological disorder groups except for those which required two sequential motor performances. In speech tasks, both consonant and vowel accuracy were significantly lower and inconsistent in childhood apraxia of speech group than in the multiple phonological disorder group. Syllable number, shape and sequence accuracy differed significantly in the childhood apraxia of speech group than the other two groups. In addition, children with childhood apraxia of speech showed greater difficulty in processing prosodic features indicating a clear need to address these variables for differential diagnosis and treatment of children with childhood apraxia of speech.     

Hyperplastic epithelial lesions of the vocal folds: combined use of exfoliative cytology and laryngostroboscopy in differential diagnosis

The mainstay of successful tumor therapy is early detection of neoplastic tissue. Although exfoliative cytology has proven to be a reliable tool, its importance is still underestimated. Laryngostroboscopy is the most important tool for functional investigation in laryngological and phoniatric diagnosis. Stroboscopic evaluation allows early detection of infiltrative processes of the vocal folds. Aim of our study was to demonstrate that combination of both, exfoliative cytology and stroboscopy, provides a highly sensitive and easy to perform method in differential diagnosis of epithelial hyperplastic lesions of the vocal folds. In 130 patients with varying degrees of vocal fold keratosis up to glottic cancer, preoperative layngostroboscopy was performed. Stroboscopy was classified pathological in case of reduced or abolished amplitude of vocal fold vibration and/or reduced or abolished mucosal wave propagation. Under general anaesthesia histology with corresponding cytological specimens were obtained. The latter were classified in three groups reaching from normal (I), dysplastic (II), up to malignant (III) cytology. Invasive carcinoma was diagnosed in 32 cases by histology, corresponding malignant cytology was found in 21 specimens (sensitivity: 74%). By certain combination of cytology with pathological stroboscopy, a sensitivity of more than 97% can be achieved. Combination of cytology and stroboscopy allows detection of glottic cancer with a sensitivity of 97%, in contrast to 74% as found by cytology alone. This combination can be used as preliminary or sorting procedure and gives the opportunity of early detection, as well as for follow-up examinations. For repeated biopsies can cause scars with consecutive voice impairment, this procedure is very smooth but nevertheless reliable method.     

Propranolol treatment in life-threatening airway hemangiomas: A case series and review of literature

Objectives

Infantile hemangiomas (IHs) in the airway may be potentially life-threatening during the proliferative phase. Available treatments like oral corticosteroids (OCS) and chemotherapeutic agents usually showed variable responses and serious side effects. Propranolol is a new and promising treatment option.

Methods

A case series of five IH patients with airway involvement is presented, supplemented with a review of literature. Propranolol treatment (2.0–3.0 mg/kg/day) was initiated between 3 weeks and 6 months of age. Three cases were treated with propranolol monotherapy, 2 cases with OCS primarily and propranolol secondarily, in which treatment with OCS could be reduced rapidly.

Results

In our case series a dramatic, fast response was observed in all cases, with a permanent effect after discontinuation in four cases. In one patient a relapse of airway problems occurred two months after discontinuation of propranolol at 16 months of age; this resolved after re-start of propranolol. Review of literature together with these five cases showed 81 patients with airway IHs treated with propranolol. Propranolol was effective in 90% of the cases and seven patients were classified as non-responders. Eight IHs relapsed while weaning of propranolol or after discontinuation; dose adjustment or restart was effective in most cases but one patient appeared resistant to therapy.

Conclusions

Propranolol seems to be a rapidly effective and safe treatment strategy for most IHs obstructing the airway. Because of the fast and important effects of propranolol, randomized controlled trials are hardly justifiable for this specific, relatively rare but, acute treatment indication. Despite the efficacy of propranolol, close monitoring of the patients with an airway IH is required, considering the risk of relapse of symptoms during or after treatment and the reported resistance to propranolol in at least 9% of the published cases. The dose and duration of treatment should be high and long enough to prevent relapse. Further research should focus on the optimal treatment protocol; the actual percentage of non-responders and also the mechanism of resistance to propranolol is unknown and needs to be illuminated.     

Practical model description of peripheral neural excitation in cochlear implant recipients: 3. ECAP during bursts and loudness as function of burst duration

In this, the third paper of the series, the loudness of low-rate bursts of electrical pulses was measured as a function of the burst duration, in subjects implanted with the Nucleus^® 24 cochlear implant system (three with straight and two with Contour™ electrode arrays). In order to help distinguish between the contributions of peripheral and more central effects, the ECAP was recorded to the individual pulses comprising the bursts, using the Neural Response Telemetry™ (NRT™) system. At a pulse rate of 250 pulses/s, the ECAP amplitude did not decrease greatly during the bursts: the mean reduction factor was 0.89. The time-constant for summation of the loudness contributions from the pulses comprising a burst was found to be larger than that associated with normal hearing. In addition, the first pulse of a pulse train was found to contribute much more to the overall loudness than did the subsequent pulses, although a corresponding difference was not observed in the ECAP recordings. These results establish a necessary connection between the essentially single-pulse model, developed in the fourth and fifth papers of the series, and the psychophysical data for pulse bursts, but they also have broader implications.     

Practical model description of peripheral neural excitation in cochlear implant recipients: 1. Growth of loudness and ECAP amplitude with current

This is the first in a series of five papers, presenting the development of a practical mathematical model that describes excitation of the auditory nerve by electrical stimulation from a cochlear implant. Here are presented methods and basic data for the subjects, who were implanted with the Nucleus^® 24 cochlear implant system (three with straight and three with Contour™ electrode arrays), required as background for all papers. The growth of subjective loudness with stimulus current was studied, for low-rate pulse bursts and for single pulses. The growth of the amplitude of the compound action potential (ECAP) was recorded using the Neural Response Telemetry™ (NRT™) system. An approximately linear relationship was demonstrated between ECAP amplitude and burst loudness, although this failed at the lower end of the dynamic range, to an extent that varied with subject and stimulated electrode. Single-pulse stimuli were audible below ECAP threshold, demonstrating that the audibility of burst stimuli at such low currents was not due solely to temporal loudness summation. An approximate function was established relating the curvature of the burst loudness growth function to the maximum comfortable level (MCL). Loudness at threshold was quantified, as a percentage of loudness at MCL. The relationship between loudness and ECAP growth functions, the curvature versus MCL function and the loudness associated with threshold are relevant to the development of a mathematical model of electrically evoked auditory nerve excitation.