Trigeminal Nerve Root Demyelination Not Seen in Six Horses Diagnosed with Trigeminal-Mediated Headshaking.

Trigeminal-mediated headshaking is an idiopathic neuropathic facial pain syndrome in horses. There are clinical similarities to trigeminal neuralgia, a neuropathic facial pain syndrome in man, which is usually caused by demyelination of trigeminal sensory fibers within either the nerve root or, less commonly, the brainstem. Our hypothesis was that the neuropathological substrate of headshaking in horses is similar to that of trigeminal neuralgia in man. Trigeminal nerves, nerve roots, ganglia, infraorbital, and caudal nasal nerves from horse abattoir specimens and from horses euthanized due to trigeminal-mediated headshaking were removed, fixed, and processed for histological assessment by a veterinary pathologist and a neuropathologist with particular experience of trigeminal neuralgia histology. No histological differences were detected between samples from horses with headshaking and those from normal horses. These results suggest that trigeminal-mediated headshaking may have a different pathological substrate from trigeminal neuralgia in man.

The effect of breech presentation on the accuracy of estimated fetal weight.

To determine whether fetal presentation affects the accuracy of ultrasonographic estimated fetal weight (EFW). This is a retrospective cohort study of singleton pregnancies that underwent ultrasonographic EFW within 3 weeks of delivery at a single institution from 1993 to 2008. Breech presenting fetuses were compared with those presenting cephalic. EFW using the Hadlock formula was compared with actual birth weight (ABW) and reported as mean difference and mean percentage difference. Differences were also considered categorically. Subgroup analyses were performed of women who delivered within 4 days of scan and excluding women with comorbidities. Ability to detect small and large for gestational age infants was compared. Evaluation of 3770 patients, 183 (4.9%) breech presenting and 3587 (95.1%) cephalic presenting revealed no difference in mean gram difference (-222.1 g ± 312.6 vs. -210.7 g ± 793.2, p = 0.084), respectively, or ability to accurately predict within 10% of ABW (adjusted odds ratio [AOR] 1.23; 95% CI, 0.89,1.69; p = 0.208). Subgroup analyses revealed similar results. There was no difference in the ability to detect small and large for gestational age infants. Presentation does not demonstrably affect the accuracy of ultrasonographic EFW when utilizing the Hadlock formula.

Sonographic evaluation and the pregnancy complicated by diabetes.

Sonography is a fundamental tool in the management of pregnancies affected by maternal diabetes. Purposeful use of ultrasound in each trimester provides an invaluable amount of information about the developing fetus including gestational age and growth patterns, anatomical structure and function, assessment of fetal well-being, and prediction of adverse outcome. There are great ongoing research efforts in this field of prenatal diagnosis and management, yet even more are needed.