Eoin Mulroy

Peripheral nerve ultrasound in cerebellar ataxia neuropathy vestibular areflexia syndrome (CANVAS)

We report preliminary findings of nerve ultrasound in patients with cerebellar ataxia neuropathy vestibular areflexia syndrome (CANVAS) who have sensory impairment due to dorsal root ganglionopathy.

Peripheral nerve ultrasound findings in mucolipidosis type 3

PurposeThe mucolipidoses are rare autosomal recessive lysosomal storage disorders. Neurologic involvement in these conditions is generally thought to be limited to cognitive delay and entrapment neuropathies (primarily carpal tunnel syndrome). We sought to evaluate peripheral nerves in this condition using nerve ultrasound.MethodsWe performed peripheral nerve ultrasound in two siblings with genetically confirmed mucolipidosis type 3 (alpha/beta).ResultsPeripheral nerves in mucolipidosis type 3 (alpha/beta) exhibit multifocal enlargement.ConclusionThe peripheral nerve ultrasound has a role in the evaluation of this, and possibly other lysosomal storage disorders.

Peripheral nerve ultrasound in Friedreich ataxia: Nerve Ultrasound in Friedreich Ataxia

Sensory impairment in Friedreich ataxia (FRDA) is generally accepted as being due to a ganglionopathy. The degree of contribution from axonal pathology remains a matter of debate. Nerve ultrasound may be able to differentiate these processes.

Forgetting the fundoscope – A case of fulminant idiopathic intracranial hypertension causing rapid visual loss

Idiopathic intracranial hypertension (IIH) is a syndrome of elevated intracranial pressure without evidence of intracranial mass lesion or venous thrombosis, and bland cerebrospinal fluid examination. It mostly affects overweight women of childbearing age and if left untreated, can lead to permanent visual loss. Visual decline in this condition is generally slow, over months to years. However, a small proportion of patients develop rapidly progressive visual loss within days or weeks of onset of headaches. We describe a 29 year-old patient with fulminant IIH in whom inadequate fundoscopy and assessment of vision contributed to a delay in diagnosis and poor outcome. Unfortunately, competence with the bedside examination technique of fundoscopy is declining. We emphasise the importance of thorough assessment of vision and fundi in patients presenting with new-onset headache.

Symptomatic intracranial hypertension during recovery from the syndrome of headache with neurologic deficits and cerebrospinal fluid lymphocytosis (HANDL)

The syndrome of headache with neurologic deficits and cerebrospinal fluid lymphocytosis (HANDL) is rare; it comprises migrainous headaches (generally in headache-naïve people), fluctuating neurological symptoms and cerebrospinal fluid (CSF) lymphocytosis. The syndrome generally runs a benign, self-limiting course over weeks. A small proportion of patients develop intracranial hypertension as a consequence of the illness. Recurrence of headaches or development of visual symptoms following apparent recovery from HANDL should prompt urgent re-evaluation for elevated intracranial pressure. Short-to-medium term management with CSF drainage and acetazolamide may be necessary to prevent visual loss.

Brain sagging syndrome presenting with chorea

Patient 1 is a 42-year-old previously well man on no medications who presented to neurology clinic with 6 months of nonpositional chronic daily headache, hiccups, and behavior change. His wife reported impulsivity, disinhibition, and sexually inappropriate behavior. There was no family history of movement disorder or neurodegenerative disease. Six weeks prior to symptom onset, he had fallen 1 meter onto his back. Vital signs, bloodwork, and general examination were normal. He was disinhibited and inattentive and exhibited orofacial, tongue, and limb choreoathetosis, which worsened over 6 months of follow-up (video at [Neurology.org/cp][1]). MRI was consistent with brain sagging syndrome; basal ganglia were subtly deformed, but without signal disturbance (figure). CSF opening pressure was 18 cm H2O. A spinal CSF leak could not be located with conventional MRI, CT myelography, or radionuclide cisternography. Oral methylprednisolone, continuous epidural saline infusion, theophylline, and 2 lumbar epidural blood patches yielded no sustained improvement. Fat saturated MRI revealed a probable CSF leak at T4, but CT-guided T4 epidural blood patch was unsuccessful. He awaits surgical exploration. [1]: http://cp.neurology.org/lookup/doi/10.1212/CPJ.0000000000000347

A tough one to swallow

A 57-year-old woman, previously well and taking no medications, gave a 2 - week history of progressive swallowing difficulty, nasal speech, nasal food regurgitation and mild limb girdle weakness . Two months before, she had developed a rash on her neck and behind her ears; by the time of presentation, this had spread to her face, scalp, elbows, knees and hands. She had no myalgia, arthralgia, fever or Raynaud’s phenomenon. Examination showed a skin rash (figure 1), weak palatal movements, absent gag reflex and mild hip flexion and shoulder abduction weakness. She required nasogastric tube feeding due to severe dysphagia. ### Question 1 What is the differential diagnosis? Figure 1 Skin rashes at the time of presentation involving the neck, periauricular region, face and knuckles. Subacute onset of bulbar palsy raises a limited number of diagnostic possibilities. Intrinsic lower brainstem lesions, motor neuron disease, Guillain-Barre syndrome, myasthenia gravis and multiple lower cranial nerve palsies should be considered, although none of these would explain the rash. Inflammatory myopathies such as inclusion body myositis and dermatomyositis can present in this fashion. In this case, skin rash might suggest dermatomyositis. Blood testing identified a serum creatine kinase concentration of 433 U/L (normal 30–180). Blood testing for vasculitis, systemic connective tissue diseases, myasthenia gravis and Lambert-Eaton myasthenic syndrome were negative or normal. Central nervous system imaging was unremarkable. Nerve conduction studies found no evidence of neuropathy and no decrement on repetitive nerve stimulation. Electromyography demonstrated low-amplitude, short-duration potentials. ### Question 2 What is the likely diagnosis and what tests would you perform? Low-amplitude, short-duration muscle action potentials on electromyography suggest a myopathy. This finding, combined with dysphagia and skin rash, suggests a diagnosis of dermatomyositis. Historically, this diagnosis relied on clinical, biochemical (raised serum creatine kinase) and electromyography findings, combined with muscle histology showing perivascular endomysial inflammation and perifascicular atrophy.1 Nowadays, however, …

079 Nerve ultrasound cross sectional area does not correlate with electrodiagnostic carpal tunnel severity in the very elderly

Introduction Ultrasound measurement of median nerve cross-sectional area (CSA) at the wrist has emerged as an accurate and useful complement to electrophysiology in the diagnosis of carpal tunnel syndrome (CTS).AANEM, 2012 A number of studies have also shown a positive correlation between median nerve CSA and electrodiagnostic severity. After noting absence of the expected nerve enlargement on ultrasound in some very elderly patients, we sought to correlate nerve ultrasound and electrodiagnostic findings in a very elderly population and to compare this with a population of younger patients. Methods We undertook a retrospective review of electrophysiology and ultrasound data collected during routine clinical practice at our institution over a 13 month period. The correlation between electrodiagnostic severity and median nerve CSA at the wrist in patients aged 40–65 years (59 patients, 70 hands) was compared with a population of very elderly patients aged ≥80 years (33 patients, 40 hands). The sensitivity of nerve ultrasound for the detection of CTS was calculated for both groups. Results In the 40–65 years age group, there was a strong positive correlation between electrodiagnostic severity and median nerve CSA (r=0.79, p<0.01). In patients aged over 80 years, there was no significant correlation between the two techniques (r=0.09, p=0.57). Compared to ‘gold standard’ electrophysiologic tests, nerve ultrasound sensitivity for the detection of CTS was 98% in the 40–65 years age group and 62% in the very elderly group. Conclusion The absence of expected median nerve enlargement in very elderly patients with electrodiagnostic evidence of CTS may reflect a different pathophysiologic response to distal median nerve entrapment in advanced age. Our data also suggests that nerve CSA measurement alone may not be a reliable tool for the detection of CTS in the very elderly. Further studies of its diagnostic accuracy in very elderly patients are warranted.

080 Electrodiagnostic and ultrasound correlates of clinical severity in ulnar neuropathy

Introduction This is a retrospective review of 135 consecutive patients (M:F=71:64, mean age 52.6 years; 141 arms) referred to our institution with ulnar neuropathy over a two year period. We analysed electrodiagnostic and ultrasound findings in relation to clinical severity. Methods All patients underwent electrodiagnostic (AAN) and ultrasound examination of the symptomatic ulnar nerve(s). Clinical severity was graded on a 4 point scale from ‘very mild’ (symptoms only) to ‘severe’ (sensory loss plus marked atrophy of ulnar-innervated hand muscles). Results In ‘very mild’ neuropathies, the number of abnormal electrodiagnostic and ultrasound studies was 2 and 11 respectively, out of 54; in ‘mild’ neuropathies 19 and 25 out of 40; in ‘moderate’, 23 and 24 out of 24; and in ‘severe’, 23 and 23 out of 23. In 25 arms, (18 of which were clinically ‘severe’ or ‘moderate’), electrophysiology was abnormal but non-localising. Ultrasound showed abnormally large cross-sectional area at the elbow in 22 and diffuse nerve enlargement in three. Ultrasound identified nerve subluxation in 24 (17%) neuropathies, 58% of which were ‘very mild’, 25% ‘mild’ and 17% ‘moderate’ or ‘severe’. Conclusion In patients with symptoms but no clinical signs, electrophysiological evidence of ulnar neuropathy was present in 3.7%, whereas abnormal nerve ultrasound, often associated with subluxation, was demonstrated in 20%. Ultrasound increased the diagnostic yield of electrophysiology in the ‘very mild’ and, to a lesser extent, the ‘mild’ neuropathies by a combined 11%, and localised the lesion in all ulnar neuropathies with abnormal but non-localising electrophysiology. Nerve subluxation was disproportionately represented amongst the clinically ‘very mild’ neuropathies with abnormal ultrasound.

Peripheral nerves are pathologically small in cerebellar ataxia neuropathy vestibular areflexia syndrome: a controlled ultrasound study

Sensory neuronopathy is a cardinal feature of cerebellar ataxia neuropathy vestibular areflexia syndrome (CANVAS). Having observed that two patients with CANVAS had small median and ulnar nerves on ultrasound, we set out to examine this finding systematically in a cohort of patients with CANVAS, and compare them with both healthy controls and a cohort of patients with axonal neuropathy. We have previously reported preliminary findings in seven of these patients with CANVAS and seven healthy controls.