The value of temporary external lumbar CSF drainage in predicting the outcome of shunting on normal pressure hydrocephalus.

OBJECTIVE: It has been reported that temporary external lumbar CSF drainage (ELD) is a very accurate test for predicting the outcome after ventricular shunting in patients with normal pressure hydrocephalus (NPH). However, only a limited number of patients have been studied for assessing the predictive accuracy of ELD. Therefore, the value of ELD in predicting the outcome after a ventriculoperitoneal shunt in patients with presumed NPH was assessed. METHODS: All patients with presumed NPH were invited to participate in this study. Clinical assessment, MRI, and neuropsychological evaluation were followed by a lumbar CSF tap test consisting of removing 40 ml CSF. When this test resulted in marked clinical improvement of gait impairment, mental disturbances, or both, the patient was shunted without further tests. In patients with either questionable or no improvement after the CSF tap test, ELD was carried out. The value of ELD for predicting the outcome after shunting was calculated by correlating the results of ELD with that of ventriculoperitoneal shunting. RESULTS: Between January 1994 and December 2000, 49 presumed NPH patients from three institutes were included. Forty three had idiopathic, and the remaining six had secondary NPH. Forty eight patients were shunted; 39 had an ELD of whom 38 completed the test. After 2 months 35 of the 48 (73%) shunted patients had improved. The predictive value of a positive ELD was 87% (95% confidence interval (95% CI) 62-98) and that of a negative ELD 36% (95% CI 17-59). In two patients serious test related complications (meningitis) occurred without residual deficit. CONCLUSION: The study suggests that although the predictive value of a positive ELD is high, that of a negative ELD is deceptively low because of the high rate of false negative results. The costs and invasiveness of the test and the possibility of serious test related complications further limits its usefulness in managing patients with presumed NPH.

Unilateral thalamic infarction and vertical gaze palsy: cause or coincidence?

Although vertical gaze palsy (VGP) is commonly associated with lesions of the rostral mesencephalon, there is some evidence that VGP may also be caused by a unilateral thalamic lesion. The case of a 68-year-old man with persistent upward gaze palsy after a unilateral thalamic infarction, demonstrated on computed tomography and magnetic resonance imaging scans, is presented. Subsequent high-resolution magnetic resonance scanning, however, showed involvement of the rostral mesencephalon as well. The authors suggest that in previous patients with VGP ascribed to a unilateral thalamic infarction, a coexisting mesencephalic involvement may have been missed because of inappropriate imaging techniques. Strong evidence of unilateral thalamic infarction as a cause of VGP is still lacking.

Diagnosis and management of normal-pressure hydrocephalus.

The syndrome of normal-pressure hydrocephalus (NPH) remains a diagnostic and therapeutic challenge, especially as many patients do not display the classical clinical and neuroimaging patterns of NPH, thus questioning the usefulness of a shunt. Gait impairment remains the cardinal symptom, while mental deterioration may be subtle and even unrecognized. NPH is rarely the cause of severe dementia, and substantial improvement in NPH-related mental deterioration is limited to 30-40% of shunted patients. Many ancillary investigations have been described that can increase the probability of selecting the appropriate candidates for a shunt. The reliability and reproducibility of these tests are limited. Unfortunately, the best predictive tests are technically complex and are used only in a few specialized centers. The best management is still to adhere to strict clinical and magnetic resonance imaging criteria and to rely on a positive - but not negative - CSF tap test and the occurrence of B-waves during at least 50% of the continuous intracranial pressure recording time, when this procedure is available.

Distal neuralgic amyotrophy.

Neuralgic amyotrophy consists of severe pain around the shoulder and arm followed by weakness in one or several muscles of the same area. We describe four patients with distal neuralgic amyotrophy in whom acute, severe, and transient pain around the shoulder or arm was followed by weakness of the forearm and hand muscles only. Minor sensory symptoms were present in only one patient. The presence of structural lesions causing the extent of the forearm and hand motor deficit was excluded by ancillary examinations. Electrophysiological studies showed a motor axonopathy and minimal sensory axonopathy. A follow-up of 2 years or longer showed either spontaneous improvement or residual motor deficit. Unfamiliarity with a clinically distal localization of neuralgic amyotrophy may result in misdiagnosis of lower cervical (poly)radiculopathy in view of the distal localization of the motor deficit and the high prevalence of coincidental abnormalities of the lower cervical spine on plain radiography, computed tomography, or magnetic resonance imaging.

Prolonged treatment with transdermal fentanyl in neuropathic pain.

Forty-eight patients with noncancer neuropathic pain who had participated in a randomized controlled trial with intravenous fentanyl (FENiv) infusions received prolonged transdermal fentanyl (FENtd) in an open prospective study. Pain relief, side effects, tolerance, psychological dependence, mood changes, and quality of life were evaluated. The value of clinical baseline characteristics and the response to FENiv also was evaluated in terms of the outcome with long-term FENtd. Eighteen patients stopped prematurely because of insufficient pain relief, side effects, or both. Among the remaining 30 patients completing the 12-week dose titration protocol, pain relief was substantial in 13 and moderate in five. Quality of life improved (23%, P < 0.01). Psychological dependence or the induction of depression was not observed. In only one patient did tolerance emerge. There was a significant positive correlation between the pain relief obtained with FENiv and that with prolonged FENtd (r = 0.59, P < 0.0001). We conclude that (1) long-term transdermal fentanyl may be effective in noncancer neuropathic pain without clinically significant management problems and (2) A FENiv-test may assist in selecting neuropathic pain patients who might benefit from prolonged treatment with FENtd.

Anticipation in familial cavernous angioma: ascertainment bias or genetic cause.

OBJECTIVES: Anticipation has been linked to unstable trinucleotide repeats in many neurological disorders. We examined the hypothesis of genetic anticipation in familial cavernous angioma (FCA) of the central nervous system. MATERIAL AND METHODS: The mean ASO of affected individuals was compared between successive generations in 55 families. Intergenerational pair-wise comparisons were employed to avoid several ascertainment biases. Regarding severity of disease both type of manifestation and number of cavernous angiomas were compared between generations. RESULTS: The mean ASO decreased significantly both from the first to the second generation (31.6 vs 17.8 years; P = 0.000) and from the second to the third generation (17.8 vs 6.7 years; P = 0.002). The pair-wise comparisons also showed significantly earlier ASO. No clear evidence for anticipation with regard to severity of disease was found. CONCLUSIONS: Molecular genetic studies will determine whether trinucleotide repeats are the underlying mechanism for our observation of anticipation in FCA.

Randomised double-blind active-placebo-controlled crossover trial of intravenous fentanyl in neuropathic pain.

BACKGROUND: The effectiveness of opioid analgesics in non-cancer neuropathic pain is unpredictable and can be disappointing. It is not clear whether opioids, when effective, relieve pain by decreasing pain intensity or pain unpleasantness or by their sedative effect. The aim of this prospective randomised double-blind placebo-controlled crossover trial was to assess relief of pain intensity and pain unpleasantness with intravenous infusions of fentanyl. METHODS: We compared the analgesic effect of intravenous dose titration of fentanyl with diazepam (active placebo) or saline (inert placebo) in 53 patients with different types of neuropathic pain. Patients were randomly assigned two consecutive infusions: fentanyl plus diazepam (27 patients) or fentanyl plus saline (26 patients). Study medication was infused at a constant rate for a maximum of 5 h. Pain, sedation, and side-effects were assessed from the start of infusion for 8 h. The primary outcome measure was maximum relief of pain intensity. FINDINGS: One patient in the fentanyl/diazepam group and two in the fentanyl/saline group were withdrawn. Maximum relief of pain intensity was better with fentanyl than with diazepam (66% [95% CI 53-80] vs 23% [12-35]) or with saline (50% [36-63] vs 12% [4-20]). The beneficial effect of fentanyl was independent of the type of neuropathic pain and the degree of sedation. Fentanyl therapy produced equal relief of pain intensity and pain unpleasantness, whereas diazepam and saline did not reduce either pain index. Patients reported significantly more side-effects while receiving fentanyl than during diazepam or saline infusion (p < 0.0001), but none of the side-effects was severe. INTERPRETATION: Fentanyl may relieve non-cancer neuropathic pain by its intrinsic analgesic effect. The clinical characteristics of neuropathic pain do not predict response to opioids.

[Clinical judgment and decision making in clinical practice. A free spirit with imminent paraplegia]. / Klinisch denken en beslissen in de praktijk. Een vrijbuiter met een dreigende dwarslaesie.

A 45-year-old man was admitted because of loss of strength in the legs and urinary retention. MRI showed enlargement of the thoracic and lumbar spinal cord from T11 to the conus medullaris. Magnetic resonance angiography and spinal angiography showed a dural arteriovenous fistula. The abnormal connection was clipped surgically after which the patient recovered fully.

Spontaneous bilateral internal carotid artery dissection and migraine: a potential diagnostic delay.

A 36-year-old man with a history of migraine without aura, presented with recurrent bouts of severe headache, perception of flashing lights in both visual fields, and transient bilateral neurological deficits. In view of his history, migraine with aura was considered. Ancillary investigations showed bilateral extracranial internal carotid artery dissection. This case illustrates that when attacks of severe headache with scotomata and transient bilateral neurological deficits occur in a patient with a history of migraine, the diagnosis of carotid artery dissection should be considered, especially when the pattern of headache is different or when some clinical characteristics have not been experienced previously.

Cavernous angiomatosis of the central nervous system: usefulness of screening the family.

A 23-year-old woman presented with cerebellar hemorrhage from a cavernous angioma (CA). A history of spinal hemorrhage and a supratentorial calcified lesion on CT and MRI suggested cavernous angiomatosis of the CNS. Familial investigation in 20 relatives revealed 4 additional patients with symptomatic CA and one person with asymptomatic CA. In the symptomatic patients, CA had not been recognized as the cause of their neurologic symptoms prior to our investigation. The number of CA lesions in asymptomatic relatives was low. This study shows that, when a patient with cavernous angiomatosis of the CNS is encountered, systematic clinical and MRI investigations in other family members with a history or symptoms of neurologic disorder should be carried out.

Prolonged remission of primary central nervous system lymphoma after discontinuation of steroid therapy.

The case of a 63-year old man is presented in whom remission of a primary central nervous system lymphoma was achieved by corticosteroids only. After discontinuation of steroid therapy the remission persisted for two and a half years. Recurrences appeared at other sites of the brain, and were steroid resistant.

Leptomeningeal plasmacytosis. Case report and considerations on treatment.

We describe a 68-year-old patient with a plasma cell leukaemia in haematological remission presenting with massive intracranial leptomeningeal plasmocytic infiltration (LPI) and hydrocephalus. He was treated with skull irradiation and a combination of intraventricular and lumbar intrathecal therapy with methotrexate. Neurologic improvement and clearance of plasma cells from the cerebrospinal fluid was reached after 2 weeks of treatment but prolonged follow-up was interrupted by a lethal gastro-intestinal haemorrhage, 6 weeks after starting the therapy. From previously reported cases it is known that LPI almost always occurs in either high-grade plasmocytomas or plasma cell leukaemia. These data suggest that therapy of LPI should be the same as in other leukaemias with leptomeningeal infiltration.