Faculty Bibliography

Eosinophilic granuloma is a localized form of histiocytosis X, or Langerhans' cell histiocytosis, a benign lesion of proliferating Langerhans' cells. It is the least severe of the histiocytosis syndromes, and is characterized by lytic lesions of one or more bones. Temporal bone lesions usually occur in association with multifocal disease; however, isolated lesions may occur in either the mastoid bone alone, or in the entire temporal bone, without disease elsewhere in the body. We present the first case (to our knowledge) of eosinophilic granuloma, or unifocal Langerhans' cell histiocytosis, limited to the petrous apex. The patient, an 8-year-old girl, presented with facial nerve paralysis. Because of delay in definitive diagnosis, the disease extended beyond its original boundaries and resulted in complete destruction of the temporal bone. We will also review Langerhans' cell histiocytosis, with attention to its involvement of the temporal bone

Few reports address using selective arterial embolization for controlling posterior epistaxis. Internal maxillary artery ligation is an effective method of control but suffers from requiring an operation in an already traumatized field and may fail due to variations in arterial arborization and collateral circulation. Selective angiographic embolization can determine the site of bleeding and control it, obviating the need for surgery, continued packing, and its sequellae. Sixteen patients underwent embolization for uncontrollable epistaxis. One patient had transient diplopia during the angiogram. There were no permanent complications. Within hours of the procedure, 12.5% experienced transient neurologic symptoms that resolved. All patients were controlled. Within 24 hours of the embolization, 87.5% were unpacked. The average length of stay was 5 days. When corrected for days admitted because of posterior packing, the length of stay decreased to 3.9 days. It is concluded that embolization is a safe, efficacious, cost efficient method of controlling posterior epistaxis

This meta-analysis of 42 empirical studies assessed the effect of six constructs on self-esteem: hearing status, parents' hearing status, type of school attended, communication mode used at home and in school, and group identification. Differences in self-esteem between deaf and hearing people varied based on (a) the self-esteem measure and (b) its format, and (c) the communication mode in which tests were administered. People whose parents were deaf compared favorably to those whose parents were hearing, as did people whose parents used sign language at home compared to those who used oral communication. School setting and classroom communication were unrelated to self-esteem. Finally, group identification was positively related to self-esteem. Results inform recommendations for guiding hearing parents in fostering self-esteem in their deaf children

Several lines of evidence suggest that excitatory synaptic transmission contributes to the maturation of precise neuronal connections. In the present study we determined whether the specific innervation pattern of single inhibitory arborizations was dependent upon neuronal activity during development. A homogeneous group of glycinergic inhibitory neurons in the central auditory system, the medial nucleus of the trapezoid body (MNTB), was functionally denervated in neonatal gerbils. The anatomical specificity of single MNTB terminal arborizations was subsequently measured along the tonotopic axis of a postsynaptic target, the lateral superior olive. Here we demonstrate that inhibitory terminal boutons spread a significantly greater distance along the frequency axis of the postsynaptic target following functional denervation. Although total arbor length remained unchanged, there was a significant increase in the number of branch points, suggesting de novo sprouting. The results indicate that normal inhibitory synaptic activity contributes to the developmental refinement of specific neuronal connections

The development of inhibitory synaptic transmission is difficult to assess because the afferents usually arise from intrinsic neurons that are difficult to stimulate independently. The postnatal maturation of excitatory and inhibitory synaptic function was compared in the gerbil lateral superior olive (LSO), where it is possible to stimulate physically discrete afferent projections. Intracellular recordings obtained in a brain slice preparation revealed that transmission was prominent at birth. The EPSPs and IPSPs were up to 2 orders of magnitude longer than in more mature animals. Brief trains of electrical stimulus pulses led to a temporal summation of postsynaptic potentials (PSPs) in 1-14 d animals resulting in prolonged depolarizations or hyperpolarizations. In neonates, the depolarization could exceed 1 sec following a 70 msec stimulus train. The IPSPs in neonates were often of sufficient amplitude to evoke a rebound depolarization or action potential. The number of converging afferents was estimated from the quantized increases in PSP size. There was a significant decrease with age, suggesting that both inhibitory and excitatory afferents were eliminated during the first 3 postnatal weeks. The integration of action potentials with IPSPs was examined with conjoint stimuli to the two afferent pathways, and demonstrated that the effective IPSP duration decreased approximately 20-fold during the first 3 postnatal weeks. The magnitudes and durations of electrical stimulus-evoked PSPs suggest that spontaneous discharge of afferents to the LSO could have a substantial impact on their development, even prior to the response to airborne sound at 12 d. Furthermore, the synaptic responses obtained at 12-14 d postnatal indicated that both amplitude and temporal processing remain compromised. These immature synaptic properties would be expected to compound the inadequacies present in the cochlea and cochlear nucleus