Brainstem auditory evoked potentials and middle latency auditory evoked potentials in young children

Measurements of brainstem auditory evoked potentials (BAEP) and middle latency auditory evoked potentials (MLAEP) are readily available neurophysiologic assessments. The generators for BAEP are believed to involve the structures of cochlear nerve, cochlear nucleus, superior olive complex, dorsal and rostral pons, and lateral lemniscus. The generators for MLAEP are assumed to be located in the subcortical area and auditory cortex. BAEP are commonly used in evaluating children with autistic and hearing disorders. However, measurement of MLAEP is rarely performed in young children. To explore the feasibility of this procedure in young children, we retrospectively reviewed our neurophysiology databank and charts for a 3-year period to identify subjects who had both BAEP and MLAEP performed. Subjects with known or identifiable central nervous system abnormalities from the history, neurologic examination and neuroimaging studies were excluded. This cohort of 93 children up to 3 years of age was divided into 10 groups based on the age at testing (upper limits of: 1 week; 1, 2, 4, 6, 8, 10 and 12 months; 2 years; and 3 years of age). Evolution of peak latency, interpeak latency and amplitude of waveforms in BAEP and MLAEP were demonstrated. We concluded that measurement of BAEP and MLAEP is feasible in children, as early as the first few months of life. The combination of both MLAEP and BAEP may increase the diagnostic sensitivity of neurophysiologic assessment of the integrity or functional status of both the peripheral (acoustic nerve) and the central (brainstem, subcortical and cortical) auditory conduction systems in young children with developmental speech and language disorders.     

Off-pump or on-pump coronary artery bypass grafting—a dilemma in elderly

Background

Off-pump coronary artery bypass graft surgery (OPCAB) has been performed for many years, but its use is increasing in frequency, and it remains an open question whether OPCAB is associated with better outcomes than on-pump coronary artery bypass graft (CABG) surgery especially in patients with age >65 years.

Methods

We randomly assigned patients 65 years of age or older who were scheduled for elective first-time CABG to undergo the procedure either without cardiopulmonary bypass (off-pump CABG) or with it (on-pump CABG). The primary end point was a composite of death, stroke, myocardial infarction, repeat revascularization, or new renal-replacement therapy at 30 days and at 12 months after surgery.

Results

A total of 581 patients underwent randomization. At 30 days after surgery, there was no significant difference between patients who underwent off-pump surgery and those who underwent on-pump surgery in terms of the composite outcome (9.8 vs. 10.1 %; odds ratio, 0.98; 95 % confidence interval [CI], 0.57 to 1.68; P?=?0.95) or four of the components (death, stroke, myocardial infarction, or new renal-replacement therapy). Repeat revascularization occurred more frequently after off-pump CABG than after on-pump CABG (1.5 vs. 0.3 %; odds ratio, 3.93; 95 % CI, 0.43 to 35.39; P?=?0.22). At 12 months, there was no significant between-group difference in the composite end point (13.1 vs. 13.3 %; hazard ratio, 0.98; 95 % CI, 0.60 to 1.58; P?=?0.94) or in any of the individual components.

Conclusions

In patients 65 years of age or older, there was no significant difference between on-pump and off-pump CABG with regard to the composite outcome of death, stroke, myocardial infarction, repeat revascularization, or new renal-replacement therapy within 30 days and within 12 months after surgery.

     

Clinical characteristics of bipolar disorder in very young children

BACKGROUND: Clinical information about bipolar disorder (BPD) in preschool-age (3-7 years old) children is extremely limited. This study examined clinical presentations, applicability of the DSM-IV diagnostic criteria, comorbidity, recovery and relapse rates, as well as some treatment strategies used in the management of BPD in preschoolers. METHODS: The charts of 26 outpatient children, ages 3-7, refereed to a child psychiatry outpatient clinic with mood and behavioral symptoms, were retrospectively reviewed. RESULTS: The majority of the patients were referred with the tentative diagnosis of ADHD but the most common diagnoses made by child and adolescent psychiatrists at the time of initial evaluation were BPD NOS (61.5%), followed by BPD I (26.9%), and mood disorder NOS (23.1%). Thirty-eight percent of the patients had one or more comorbid diagnoses. The most common presenting symptoms were irritability (84.6%) and aggression (88.5%). The most widely prescribed class of medications after diagnosis in the clinic was atypical antipsychotics and mood stabilizers. Twenty-six percent of the patients were treated with a combination of atypical antipsychotics and mood stabilizers. LIMITATIONS: Retrospective design; small sample size; lack of a comparison group. CONCLUSIONS: The course of BPD with onset in preschool years is complicated with high recovery and relapse rates. The questions of development of age-appropriate diagnostic criteria, long-term prognosis and treatment strategies used in this population require further intensive investigation.     

Potential neuroprotective role of astroglial exosomes against smoking-induced oxidative stress and HIV-1 replication in the central nervous system

Introduction: HIV-1-infected smokers are at risk of oxidative damage to neuronal cells in the central nervous system by both HIV-1 and cigarette smoke. Since neurons have a weak antioxidant defense system, they mostly depend on glial cells, particularly astrocytes, for protection against oxidative damage and neurotoxicity. Astrocytes augment the neuronal antioxidant system by supplying cysteine-containing products for glutathione synthesis, antioxidant enzymes such as SOD and catalase, glucose for antioxidant regeneration via the pentose-phosphate pathway, and by recycling of ascorbic acid.

Areas covered: The transport of antioxidants and energy substrates from astrocytes to neurons could possibly occur via extracellular nanovesicles called exosomes. This review highlights the neuroprotective potential of exosomes derived from astrocytes against smoking-induced oxidative stress, HIV-1 replication, and subsequent neurotoxicity observed in HIV-1-positive smokers.

Expert opinion: During stress conditions, the antioxidants released from astrocytes either via extracellular fluid or exosomes to neurons may not be sufficient to provide neuroprotection. Therefore, we put forward a novel strategy to combat oxidative stress in the central nervous system, using synthetically developed exosomes loaded with antioxidants such as glutathione and the anti-aging protein Klotho.     

Incidental detection of calcified left coronary artery pseudoaneurysm years after surgery for TOF

We present images from computed tomography angiography in a 40-year-old female with a calcified pseudo-aneurysm in her left coronary artery, who had previously undergone repair of tetralogy of Fallot.     

A two-vessel aortic arch: Rare configuration with bilateral brachiocephalic arteries

We present a case of type B aortic dissection with a rare aortic arch branching variation whereby two separate brachiocephalic trunks arise from the arch. This case also highlights the potential implications of this variant in the management of thoracic aortic dissections and aneurysms.