Search results for "brain stem"
showing 10 items of 86 documents
Isolated superior oblique palsies with brainstem lesions
1999
Article abstract Isolated unilateral superior oblique palsies resulting from brainstem lesions occurred in three patients. MRI documented contralateral tegmental lesions of the trochlear nucleus and adjacent intraaxial trochlear nerve. Lacunar infarct was the cause in two patients and a small hemorrhage in a third.
Utility of post mortem computed tomography in clivus fracture diagnosis. Case illustration and literature review
2017
Clivus fractures are usually associated with head blunt trauma due to traffic accident and falls. A 23 - year-old man died immediately after a smash-up while he was stopping on his motorcycle. Post-mortem Computed tomography (PMCT), performed before autopsy, revealed a complex basilar skull base fractures associated with brainstem and cranio-vertebral junction injuries, improving the diagnostic performance of conventional autopsy. Imaging data were re-assessable and PMCT offers the possibility to perform multiplanar and volume rendered reconstructions, increasing forensic medicine knowledge related to traumatic injuries.
Gentamicin alters Akt-expression and its activation in the guinea pig cochlea
2015
Gentamicin treatment induces hair cell death or survival in the inner ear. Besides the well-known toxic effects, the phosphatidylinositol-3 kinase/Akt (PI3K/Akt) pathway was found to be involved in cell protection. After gentamicin application, the spatiotemporal expression patterns of Akt and its activated form (p-Akt) were determined in male guinea pigs. A single dose of 0.1 mL gentamicin (4 mg/ear/animal) was intratympanically injected. The auditory brainstem responses (ABRs) were recorded prior to application and 1, 2 and 7 days afterward. At these three time points the cochleae (n=10 in each case) were removed, transferred to fixative and embedded in paraffin. Seven ears were used as u…
Evidence for increased nitric oxide production in the auditory brain stem of the aged dwarf hamster (Phodopus sungorus): an NADPH-diaphorase histoche…
2000
Age-related changes of the auditory system such as presbyacusis are believed to be due, at least in part, to alterations of central structures. The superior olivary complex (SOC), a group of interrelated brain stem nuclei, projects to a variety of neuronal structures including the cochlea and the inferior colliculus (IC). The soluble gas nitric oxide (NO), believed to function as a neuroactive substance within the SOC and cochlea, is thought to be involved in ageing processes. Since it is unknown whether NO-production is altered in the ageing auditory system, the present study was conducted to investigate whether the number of NO-producing cells in the SOC is changed with increasing age. Th…
Projection Neurons in the Superior Olivary Complex of the Rat Auditory Brainstem: A Double Retrograde Tracing Study
1998
The superior olivary complex (SOC), a group of interrelated brainstem nuclei, sends efferents to a variety of neuronal structures including the cochlea and the inferior colliculus (IC). In the present study conducted in rats, we sought to investigate whether single SOC efferent neurons project to both cochlea and IC. These neurons were identified by retrograde axonal transport of the neuronal tracers fluoro-gold upon application to the cochlea and cholera toxin B subunit injected into the central nucleus of the IC. Projections to the cochlea were found to stem predominantly from the ipsilateral lateral superior olive (LSO) and medial superior olive (MSO) as well as from the bilateral superi…
Comparison of the brainstem auditory evoked responses during sevoflurane or alfaxalone anaesthesia in adult cats.
2017
Abstract Objective To compare the effects of general anaesthesia using sevoflurane or alfaxalone on the brainstem auditory evoked response (BAER) test in adult healthy cats. Study design Prospective, clinical, ‘blinded’, crossover study. Animals Ten feral adult healthy cats. Methods Premedication consisted of dexmedetomidine (0.01 mg kg –1 ) intramuscularly (IM). The first general anaesthesia was induced and maintained with sevoflurane (treatment S) for physical examination, BAER test, complete blood tests, thoracic radiographs and abdominal ultrasound. The second general anaesthesia was induced with alfaxalone (treatment A) IM (2 mg kg –1 ) and maintained with alfaxalone (10 mg kg –1 hour …
A possible biomarker for methadone related deaths
2017
Abstract Methadone (MTH) concentrations in those dying of MTH toxicity totally overlap concentrations where the presence of MTH is only an incidental finding, making it very difficult to make distinctions in actual cases. A biomarker, be it anatomical or biochemical for MTH toxicity is badly needed, particularly if that markers were known to disrupt effective ventilation. Because the brainstem houses the regulatory centers for cardiorespiratory-control enters, it would seem to be the most likely anatomical site to seek abnormalities in cardiorespiratory control. Objective To locate and describe the cells of nucleus of the solitary tract (TS)(NTS) in human brainstem and determine if neuronal…
Blink reflex R2 changes and localisation of lesions in the lower brainstem (Wallenberg's syndrome): an electrophysiological and MRI study
1999
OBJECTIVES—Pathways of late blink reflexes are detected by high resolution MRI. Electronically matched stroke lesions superimposed to an anatomical atlas show the suspected course. METHODS—Fifteen patients with infarction of the lower brainstem, MRI lesions and electrically elicited blink reflexes were examined. The involved structures in patients with R2 and R2c blink reflex changes were identified by biplane high resolution MRI with individual slices matched to an anatomical atlas at 10 different levels using digital postprocessing methods. RESULTS—The blink reflexes were normal in five of 15 patients (33%) and showed loss or delay of R2 and R2c to stimulation ipsilaterally to lesion (R2-…
Prevalence and risk factors for sensorineural hearing loss: Western Sicily overview.
2013
The objective of this work was to evaluate the prevalence of sensorineural hearing loss (SNHL) and distribution of the main risk factors associated to it focusing on their role in the development of deafness and their interaction. We performed a global audiological assessment (through TEOAE, tympanometry and ABR) in 508 infants at risk studying the main risk factors reported by Joint Committee on Infant Hearing (2007). Fifty-one infants (10.03 %) were diagnosed with SNHL (45 bilateral and 6 unilateral) with a mean hearing threshold of 87.39 ± 28.25 dB HL; family history of hearing impairment (HI) and TORCH infections indicated independent significant risk factors (P < 0.00001 and P = 0.0…
Audiologic profile of infants at risk: experience of a Western Sicily tertiary care centre.
2012
Objective: To identify the incidence of sensorineural hearing loss (SNHL) on infant at risk and to classify the degree and type of hearing loss describing the main causes associated in Western Sicily. To compare single TEOAE and combined TEOAE/ABR techniques studying the referral rate, the false-positive and false-negative rates through concordance test (κ coefficient), sensitivity (TPR) and specificity (TNR) for each protocol. Methods: From January 2010 to June 2011, 412 infants at risk, ranging from 4 to 20 weeks of life, transferred to Audiology Department of Palermo from the births centers of Western Sicily, underwent to audiological assessment with TEOAE, tympanometry and ABR. The foll…