Apathy in rapid eye movement sleep behaviour disorder is common and under-recognized.

BACKGROUND AND PURPOSE: Apathy is an important neuropsychiatric feature of Parkinson's disease (PD), which often emerges before the onset of motor symptoms. Patients with rapid eye movement sleep behaviour disorder (RBD) have a high probability of developing PD in future. Neuropsychiatric problems are common in RBD, but apathy has not previously been detailed in this key prodromal population. METHODS: Eighty-eight patients with polysomnographically proven RBD, 65 patients with PD and 33 controls were assessed for apathy using the Lille Apathy Rating Scale. Cognition and depression were also quantified. The sensitivity of the Unified Parkinson's Disease Rating Scale screening questions for apathy and depression was calculated. RESULTS: A total of 46% of patients with RBD were apathetic, compared with 31% of patients with PD in our sample. Most patients with RBD with depression were apathetic but more than half of apathetic patients were not depressed. The sensitivity of the single Unified Parkinson's Disease Rating Scale screening question was only 33% for mild apathy and 50% for severe apathy. CONCLUSIONS: Apathy is common in RBD and is underestimated by a single self-report question. Recognition of apathy as a distinct neuropsychiatric feature in RBD could aid targeted treatment interventions and might contribute to the understanding of prodromal PD.

Sleep disturbance in patients taking opioid medication for chronic back pain.

Poor sleep is an increasingly recognised problem with chronic pain and further increases the effect on daily function. To identify the relationship between chronic pain, opioid analgesia and sleep quality, this study investigated activity and sleep patterns in patients taking opioid and non-opioid analgesia for chronic back pain. Thirty-one participants (10 healthy controls, 21 patients with chronic pain: 6 on non-opioid medication; 15 on opioid medication) were assessed using actigraphy, polysomnography and questionnaires. Patients with chronic pain subjectively reported significant sleep and wake disturbances as shown by decreased overall sleep quality (Pittsburgh Sleep Quality Index, p < 0.001), increased symptoms of insomnia (Insomnia Severity Index, p < 0.001) and increased fatigue (Fatigue Severity Scale, p = 0.002). They also spent increased time in bed (p = 0.016), took longer to get to sleep (p = 0.005) and had high interindividual variability in other measures of activity but no overall irregular rest-activity pattern. Patients on high doses of opioids (> 100 mg morphine-equivalent/day) demonstrated distinctly abnormal brain activity during sleep suggesting that polysomnography is necessary to detect sleep disturbance in this population in the absence of irregular rest-activity behaviour. Night-time sleep disturbance is common in individuals suffering from chronic pain and may be further exacerbated by opioid treatment. Considerations must be made regarding the appropriate use of combined actigraphy and miniaturised polysomnography for future population-based studies.

Autosomal dominant SCN8A mutation with an unusually mild phenotype.

BACKGROUND: Mutations in SCN8A, coding for the voltage-gated sodium channel Nav 1.6, have been described in relation to infantile onset epilepsy with developmental delay and cognitive impairment, in particular early onset epileptic encephalopathy (EIEE) type 13. CASE REPORT: Here we report an infant and his father with early onset focal epileptic seizures but without cognitive or neurological impairment in whom next generation sequence analysis identified a heterozygous mutation (c.5630A > G, p. (Asn1877Ser)) in the SCN8A gene. This mutation, confirmed by Sanger sequence analysis, affects a highly conserved amino acid and in silico tools predicts that it may be pathogenic. The reported infant has a normal developmental profile at 16-month follow-up. His father also had normal development and has no cognitive impairment at 42 years. This is the second known SCN8A mutation associated with a phenotype of benign familial infantile epilepsy. Good seizure control was achieved in our patients with sodium channel blockers. CONCLUSION: Based on our proband and a recently described group of families with benign familial infantile epilepsy and SCN8A variant we suggest expanding testing to patients with infantile epilepsy and no cognitive impairment. In addition, the same SCN8A variant (c.5630A > G, p. (Asn1877Ser)) is also found in patients with epilepsy and developmental delay highlighting the phenotypic variability and the possible role of other protective genetic factors.

Transcallosal resection of hypothalamic hamartoma for gelastic epilepsy.

INTRODUCTION: Hypothalamic hamartomas (HHs) are commonly associated with severe epilepsy resistant to anticonvulsant therapy. Historically, surgical resection of HHs resulted in considerable morbidity. DISCUSSION: Two series of patients who successfully underwent resection using a transcallosal approach have now been published; we report the first UK experience of this technique in a series of five patients with HHs and gelastic epilepsy resistant to anticonvulsant therapy. Patients were assessed pre- and postoperatively for seizure activity, endocrine function, ophthalmology, and neurocognitive function. Two patients had precocious puberty and all had evidence of developmental delay and behavioral problems. Postoperatively, all children experienced at least a 50% reduction in seizure frequency with abolition of major seizure types; one child remains seizure-free. One child developed a mild postoperative right hemiparesis and one developed transient diabetes insipidus. CONCLUSION: There were no adverse developmental effects of surgery. Transcallosal resection of HHs ameliorates resistant epilepsy syndromes associated with HH.

Five cases of brain injury following amniocentesis in mid-term pregnancy.

This paper describes the neuroimaging and neuropathological findings in five cases of severe brain damage after traumatic mid-trimester amniocentesis, all performed between 1986 and 1994. Although fetal injury after amniocentesis has been reported, reports of brain injury are infrequent. Continuous ultrasound monitoring may reduce the risk of fetal injury but follow-up ultrasound scans can be falsely reassuring. Withdrawal of blood-stained fluid, particularly if it contains tissue fragments, should alert the operator to the possibility of fetal damage. Histological examination of such tissue fragments may confirm the nature of the fetal damage. The consequences of fetal brain injury are severe, all five of our cases showed evidence of disruption of brain development compatible with mid-term injury. Obstetricians and their patients should be aware of the small but significant risk of brain damage after mid-term amniocentesis.

Treatment of photosensitive epilepsy using coloured glasses.

A recently introduced optometric technique, colorimetry, enables the perceptual effects of ophthalmic tints to be evaluated subjectively, optimized, and then prescribed in tinted spectacles. The new technique is beneficial in reducing visual stress in patients with dyslexia and migraine. We describe an open trial designed to ascertain: (1) whether the colorimetry assessment, as it is now given, is safe for the investigation of photosensitive patients in optometry clinics where colorimetry equipment is most readily available, but where EEG control is not practical; (2) what proportion of patients with photosensitive epilepsy is likely to benefit to the extent already described in individual cases; (3) whether a tint selected by colorimetry could be shown to reduce the incidence of paroxysmal epileptiform EEG activity in response to flicker and patterns, thereby validating the subjective methods and corroborating the reported seizure reduction. Twenty-four females and nine males (aged 12-43 years) took part. All the patients had suffered visually-provoked seizures, had exhibited a photoparoxysmal response on at least one previous EEG recording, and had received a diagnosis of photosensitive epilepsy. Twenty-two were currently experiencing seizures. A further EEG was recorded in all except seven cases: a routine resting record, followed by hyperventilation. Colorimetry was performed after hyperventilation and before photic stimulation. Twenty-three (70%) reported beneficial effects during colorimetry and were prescribed glasses. There was a preponderance of lenses with a rose or purple colour, in contrast to patients with dyslexia. Seventeen of the 23 patients were available at follow-up, an average of 2.4 years later. Thirteen (57%) reported benefits, and said they were still using the lenses. In six of the 13 the benefits were pronounced, including a reduction of dizziness from fluorescent lighting, elimination of aura when using computer screens etc. Only in three cases was there a reduction in seizures that could reasonably be attributed to the use of lenses; in two of these cases no medications were prescribed, and in the third the medications remained unchanged for four years, two before and two after the introduction of the glasses. In an additional four cases a reduction in seizures was observed but medication had been changed. There was a modest reduction in EEG photosensitivity with the coloured lenses but also to an equivalent or lesser extent with grey in all of the eight patients examined in this way. One patient had seizures during colorimetry, but the seizures were not accompanied by scalp EEG changes.

Non-convulsive status epilepticus.

The clinical, electrographic and reported neuropsychological features of 50 children with non-convulsive status epilepticus (NCSE) were reviewed and the children's progress followed for one to five years. NCSE occurred in a variety of epilepsies, especially the Lennox-Gastaut syndrome. Clinical manifestations ranged from obvious mental deterioration to subtle changes. The condition had often been overlooked or misinterpreted and many children had experienced repeated episodes over long periods. Following diagnosis, immediate treatment was often not attempted or was not successful. Further episodes of NCSE occurred in the majority of children during the follow up period. Failure to recognise NCSE and to treat episodes promptly, and the high rate of recurrence, is of particular concern in view of fears that repeated exposure to this condition might be brain damaging. At least 28 children in the present series showed evidence of intellectual or educational deterioration over the period during which NCSE had occurred, although the exact cause was difficult to determine.

Psychological effects of sodium valproate and carbamazepine in epilepsy.

Information from standardised tests of intelligence, school attainments, attention, memory and visuomotor function, together with parent and teacher questionnaire information about various aspects of behaviour, was obtained for 63 schoolchildren with newly diagnosed epilepsy before treatment with sodium valproate or carbamazepine, and again at intervals for a total period of 12 months. The same information was collected on 47 matched controls. The children with epilepsy represented those under non-specialised paediatric care. The result showed that both drugs were effective in most cases at modest dosage without causing notable psychological effects 12 months into treatment. Modest and temporary adverse cognitive effects seen earlier in treatment could have been the result of uncontrolled seizure discharge. Improved function was the same in children with epilepsy and controls. Some psychological abnormalities in the children with epilepsy were evident before treatment suggesting early unwanted effects of the epileptic process itself.

Narcolepsy.

The symptom of excessive sleepiness in children and adolescents does not necessarily cause great concern to families and professionals involved in their care. Children may deny the symptom and minimise the adverse effects. These factors contribute to an underdiagnosis of narcolepsy in this age group when clinical diagnosis is difficult as associated symptoms may not have appeared or are hard to elicit. In this paper three children whose difficult behaviour contributed to the presentation of their sleep disorder are described.

Frontal lobe complex partial seizures in children: a form of epilepsy at particular risk of misdiagnosis.

The clinical and EEG findings are described of six children considered to have complex partial seizures of frontal lobe origin. The findings correspond generally with those reported for adult patients. Video-recordings of attacks in some cases and ictal cassette EEG recordings provided important diagnostic information. A definite frontal abnormality on neuro-imaging was seen in only one case. The seizures were closely associated with sleep, and anti-epileptic drug treatment was usually of limited value. The considerable diagnostic confusion surrounding seizures of this type, including their misdiagnosis as pseudoseizures or primary sleep disorder, is partly the result of the clinical peculiarities of this type of seizure, but also of clinicians' limited awareness of the condition.

Antecedent events in motor neuron disease.

Sixty-three patients with motor neuron disease and sixty-one controls matched for age and sex were interviewed concerning life events. An antecedent history of back injuries was found more often and there was an increased incidence of prior electric shock amongst the patients. No increase of head injuries, fractures, malignancy or previous poliomyelitis was detected.