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Purpose: There has been increasing interest in identifying non-invasive, imaging biomarkers for neurodegenerative disorders of the central nervous system (CNS). The aim of this proof-of-concept study was to investigate whether corneal sensory nerve and dendritic cell (DC) parameters, captured using in vivo confocal microscopy (IVCM), are altered in individuals with mild cognitive impairment (MCI) and Alzheimer's disease (AD). Methods: Fifteen participants were recruited from the Australian Imaging Biomarkers and Lifestyle (AIBL) study in Melbourne, VIC, Australia. The cohort consisted of cognitively normal (CN) individuals (n = 5), and those with MCI (n = 5) and AD (n = 5). Participants underwent a slit lamp examination of the anterior segment, followed by corneal imaging using laser-scanning in vivo confocal microscopy (IVCM) of the central and inferior whorl regions. Corneal DC density, field area, perimeter, circularity index, aspect ratio, and roundness were quantified using Image J. Quantitative data were derived for corneal nerve parameters, including nerve fiber length (CNFL), fiber density (CNFD), branch density (CNBD), and diameter. Results: Corneal DC field area and perimeter were greater in individuals with MCI, relative to CN controls, in both the central and inferior whorl regions (p < 0.05 for all comparisons). In addition, corneal DCs in the whorl region of MCI eyes had lower circularity and roundness indices and a higher aspect ratio relative to CNs (p < 0.05 for all comparisons). DC density was similar across participant groups in both corneal regions. There was a trend toward lower quantitative parameters for corneal nerve architecture in the AD and MCI groups compared with CN participants, however, the inter-group differences did not reach statistical significance. Central corneal nerve diameters were similar between groups. Conclusion: This study is the first to report morphological differences in corneal DCs in humans with MCI. These differences were evident in both the central and mid-peripheral cornea, and in the absence of significant nerve abnormalities or a difference in DC density. These findings justify future large-scale studies to assess the utility of corneal IVCM and DC analysis for identifying early stage pathology in neurodegenerative disorders of the CNS. [ABSTRACT FROM AUTHOR]

Case History: Dairy cows recumbent following calving on farms in South Gippsland, Australia were examined during two 3-month seasonal calving periods in 2011 and 2012 as part of a larger study of 218 recumbent cows. A cohort of 104 cows diagnosed with calving paralysis following dystocia was derived from the larger group, which were examined with 3 days of becoming recumbent. A thorough medical and musculoskeletal clinical examination was performed on each cow including flexor-withdrawal and patellar reflex tests, and postural assessment in the lifted position, unless the facilities were not available. Cows were diagnosed with one or more neurological syndromes: sciatic, tibial paresis, obturator or femoral, based on clinical findings consistent with damage to these peripheral nerves or their nerve roots. Clinical Findings: Evidence of sciatic syndrome was found in 100/104 (96.2%) cows and 146/172 (84.9%) affected hind limbs either as the sole neuropathy or in combination with tibial paresis, obturator or femoral syndromes. Pelvic damage was also present in 3/104 (2.8%) cows. Obturator syndrome was diagnosed in 30/104 (29%) cows and 45/172 (26.2%) affected hind limbs but not apparently as the sole reason for the recumbency. Femoral syndrome occurred in 16/104 (15.4%) cows and 21/172 (12.2%) affected hind limbs and was the only syndrome recorded in one cow. Clinical Relevance: Sciatic syndrome was the most common neurological syndrome observed in cows with calving paralysis. The other major nerves arising from the lumbo-sacral plexus were also affected and the various syndromes associated with damage to these nerves or their ventral nerve roots occurred in many combinations. Calving paralysis should be thought of as a paresis or paralysis resulting from damage to the ventral nerve roots of the lumbo-sacral plexus as any of the nerves originating from this plexus can be damaged during dystocia either individually or in combination with other nerves from the plexus. [ABSTRACT FROM AUTHOR]

Aim: Intravenous immunoglobulin (IVIG) is an expensive therapy used in immunodeficiency and autoimmune disorders. Increasing demands and consequent shortages result in a need for usage to conform to guidelines.Method: We retrospectively evaluated IVIG use for neuroimmunological indications and adherence to existing guidelines in a major Australian paediatric hospital between 2000 and 2014.Results: One-hundred and ninety-six children (96 male, 100 female; mean age at disease onset 6y 5mo [range 3mo-15y 10mo], mean age at first IVIG dose 7y 2mo [range 3mo-16y 5mo]) received IVIG for neuroimmunological indications during the study period (28.1% had Guillain-Barré syndrome), representing 15.5% of all hospital indications. In total, 1669 IVIG courses were administered (total 57 221g, median 78g/patient, range 12-5748g). The highest median numbers of courses were in chronic inflammatory demyelinating polyneuropathies, opsoclonus-myoclonus ataxia syndrome, suspected immune-mediated epilepsies, and Rasmussen's encephalitis. Adverse reactions occurred in 25.5% of patients, but these were mostly minor. Outcome at follow-up was best in anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis, Guillain-Barré syndrome, and myasthenia gravis, and worst in Rasmussen's encephalitis and epilepsies. The total cost of IVIG was US$2 595 907 (median $3538/patient, range $544-260 766). Of patients receiving IVIG, 45.4% to 57.1% were given the therapy for 'weak' indications or indications 'not listed' in international guidelines. Some entities commonly treated with IVIG in current practice, such as anti-NMDAR encephalitis and transverse myelitis, are not listed in most guidelines.Interpretation: Our study demonstrates that IVIG is generally well tolerated but expensive, and discloses discrepancies between guidelines and clinical practice in paediatric neurology, suggesting both the need for greater adherence to current recommendations, and for recommendations to be updated to accommodate emerging indications. [ABSTRACT FROM AUTHOR]

The authors assess the knowledge of junior medical staff on peripheral nerve anatomy in Australia. They drafted a free-text written questionnaire to address the motor and sensory function of peripheral nerves. They emphasized the poor knowledge of junior doctors on peripheral nerve anatomy. They also stressed that the condition is likely to reflect the problem on the delivery of anatomy education and their support on the development of a national anatomy curriculum.

Cases of canine neural angiostrongylosis (NA) with cerebrospinal fluid (CSF) evaluations in the peer-reviewed literature were tabulated. All cases were from Australia. A retrospective cohort of 59 dogs was contrasted with a series of 22 new cases where NA was diagnosed by the presence of both eosinophilic pleocytosis and anti-Angiostrongylus cantonensis immunloglobulins (IgG) in CSF, determined by ELISA or Western blot. Both cohorts were drawn from south east Queensland and Sydney. The retrospective cohort comprised mostly pups presented for hind limb weakness with hyperaesthesia, a mixture of upper motor neurone (UMN) and lower motor neurone (LMN) signs in the hind limbs and urinary incontinence. Signs were attributed to larval migration through peripheral nerves, nerve roots, spinal cord and brain associated with an ascending eosinophilic meningo-encephomyelitis. The contemporary cohort consisted of a mixture of pups, young adult and mature dogs, with a wider range of signs including (i) paraparesis/proprioceptive ataxia (ii) lumbar and tail base hyperaesthesia, (iii) multi-focal central nervous system dysfunction, or (iv) focal disease with neck pain, cranial neuropathy and altered mentation. Cases were seen throughout the year, most between April and July (inclusive). There was a preponderance of large breeds. Often littermates, or multiple animals from the same kennel, were affected simultaneously or sequentially. A presumptive diagnosis was based on consistent signs, proximity to rats, ingestion/chewing of slugs or snails and eosinophilic pleocytosis. NA was diagnosed by demonstrating anti-A. cantonensis IgG in CSF. Detecting anti-A. cantonensis IgG in serum was unhelpful because many normal dogs (20/21 pound dogs; 8/22 of a hospital population) had such antibodies, often at substantial titres. Most NA cases in the contemporary series (19/22) and many pups (16/38) in the retrospective cohort were managed successfully using high doses of prednisolone and opioids. Treatment often included antibiotics administered in case protozoan encephalomyelitis or translocated bacterial meningitis was present. Supportive measures included bladder care and physiotherapy. Several dogs were left with permanent neural deficits. Dogs are an important sentinel species for NA. Human cases and numerous cases in tawny frogmouths were reported from the same regions as affected dogs over the study period. [ABSTRACT FROM AUTHOR]

Background and Objectives: Local anesthetic systemic toxicity (LAST) is a potentially life-threatening complication of local anesthetic administration. In this article, the results of the Australian and New Zealand Registry of Regional Anaesthesia were analyzed to determine if ultrasound-guided peripheral nerve blockade (PNB) was associated with a reduced risk of LAST compared with techniques not utilizing ultrasound technology., Methods: The period of study for this multicenter study involving 20 hospitals was from January 2007 through May 2012. The primary outcome was LAST comprising minor, major, and cardiac arrest (due to toxicity) events determined using standardized definitions. Multivariable logistic regression models and propensity score analyses were used to determine significant event predictors., Results: The study population comprised 20,021 patients who received 25,336 PNBs. There were 22 episodes of LAST, resulting in an incidence of LAST of 0.87 per 1000 PNBs (95% confidence interval, 0.54-1.3 per 1000). Ultrasound guidance was associated with a reduced incidence of local anesthetic toxicity. Site of injection, local anesthetic type, dose per weight, dose, and patient weight were all predictors of LAST., Conclusions: This study provides the strongest evidence, to date, that ultrasound guidance may improve safety because it is associated with a reduced risk of LAST following PNB.