[Idiopathic intracranial hypertension and obesity]. / Idiopathische intracraniële hypertensie bij obesitas.

BACKGROUND: Idiopathic intracranial hypertension (IIH) is a neurological syndrome characterized by elevated intracranial pressure in the absence of intracerebral abnormalities or hydrocephalus. CASE DESCRIPTION: A 17-year-old girl gained more than 25 kg in weight during treatment with risperidone and subsequently developed headache, diplopia and loss of vision due to IIH. After insertion of a ventriculoperitoneal drain and discontinuation of risperidone she lost weight and her symptoms improved. Her visual functions recovered almost fully during follow-up. CONCLUSION: Patients with IIH are mainly overweight young women who present with raised intracranial pressure evidenced by headache, nausea, vomiting and vision disturbances. Prescribed medication-induced weight gain may lead to IIH. Treatment of IIH should be focused on the prevention of severe and irreversible loss of vision.

Nonlinear analysis of EEG in septic encephalopathy.

Electroencephalograms (EEG) were recorded in fourteen patients who experienced a severe septic encephalopathy (SE). EEG analysis included visual inspection, spectral analysis and a recently developed nonlinear analysis (the Kaplan test). All EEGs showed decreased fast activity and an increase of slow wave activity on visual inspection. There was a nonsignificant trend of negative correlation between the spectral EEG analysis and the severity of the acute systemic illness (based on the sum score of 14 variables known as APACHE II score) (standard coefficient = -0.43, p = 0.118). However, a much more pronounced and significant negative correlation was observed between the Kaplan test and the APACHE II score (standard coefficient = -0.94, p = 0.005). The EEG abnormalities seen in these patients were independent of the sedation level. Neither the EEG parameters, nor the APACHE II score, predicted outcome. Nonlinear analysis is more powerful than spectral analysis to extract clinical relevant information from EEGs in patients who experience a severe SE. The nonlinear EEG analysis suggest that brain dynamics in SE may be characterized by a shift into a fundamentally different level of cortical information exchange which can be summarized in nonlinear terminology as a loss of deterministic structure in the EEG.

Transcranial Doppler and systemic hemodynamic studies in septic shock.

The present study outlines the relationship between cerebral and systemic hemodynamics in patients with septic shock. Sepsis is an immune mediated systemic disease in which the systemic vascular resistance (SVR) often decreases as a result of a Gram negative sepsis. The result is a hyperdynamic systemic circulation with redistribution phenomena in different organ systems. In order to study the effect of sepsis on cerebral vessels 20 patients with septic shock (12 men, 8 women, mean age 57.9 years) were subjected to both pulmonary artery catheter and transcranial Doppler (TCD) monitoring. The data were correlated to the APACHE II score and outcome. The study showed that cerebral mean and end-diastolic blood flow velocities (BFV) in the middle cerebral arteries significantly enhanced if the SVR-index decreases. In some patients a severely reduced SVRI (below 500 dynes.s/cm5.m2) was observed in combination with a downstroke latent steal phenomenon. TCD abnormalities were strongly related to disease severity and outcome. The increased BFV are explained by a mild vasospasm of the basal cerebral arteries. TCD appears to be a valuable tool to monitor the cerebral hemodynamics in these patients. They are particularly at risk for ischemic brain damage if they are subjected to therapeutic or spontaneous hyperventilation, which can potentially be detected by TCD.

Relationship between atlanto-odontoid osteoarthritis and idiopathic suboccipital neck pain.

We discuss the relationship of atlanto-odontoid (AO) (anterior C1-C2 joint) osteoarthritis to suboccipital pain. A questionnaire regarding suboccipital neck pain was presented to 210 consecutive patients undergoing computed tomography (CT) of the brain or sinuses for a variety of indications. In all patients the AO joint and the lateral scout image of the cervical spine were studied. In 104 (49%) degenerative changes were seen at the AO joint. There were 89 patients (42%) who reported pain in the suboccipital region, although this was not the reason for CT in any patient. Statistical analysis of the prevalence of suboccipital neck pain in all patients showed the presence of AO osteoarthritis seen on CT to be associated with occurrence of these symptoms. This association remained significant in the same study population after excluding patients with a history of rheumatoid arthritis, migraine, stress and neck trauma and patients with signs of degenerative changes of C2-C7 on the computed lateral scout image.

Association of transverse ligament calcification with anterior atlanto-odontoid osteoarthritis: CT findings.

The craniocervical junction was assessed in 700 consecutive unselected patients undergoing CT of the brain or paranasal sinuses, to investigate whether transverse ligament calcification was associated with advanced degenerative changes at the anterior atlanto-odontoid (AO) joint. Calcific deposits within the transverse ligament were seen in 40 patients (5.7%). The prevalence of this condition increased with age. Advanced degenerative changes (marked osteophytes and obliteration of the joint space) at the anterior AO joint were significantly more frequent in patients with transverse ligament calcification than in age-matched controls. We conclude that transverse ligament calcification is seen frequently in the elderly and very frequently with advanced degenerative changes at the anterior AO joint.

Atlanto-odontoid osteoarthritis. Appearance and prevalence at computed tomography.

STUDY DESIGN: In this prospective study, the authors evaluated the atlanto-odontoid (AO) joint in 500 consecutive patients who underwent computed tomographies (CTs) of the brain or paranasal sinuses. OBJECTIVES: The objective of the study was to determine age specificity of various morphologic abnormalities related to osteoarthritis at the AO joint in patients referred for CT primarily to exclude brain or sinus abnormalities. SUMMARY OF BACKGROUND DATA: In all patients, at least two axial slices through the AO joint were evaluated by two authors, and agreement was reached by consensus. METHODS: Abnormal morphology was categorized into three groups: (1) osteophytosis; (2) obliteration of the joint space; and (3) transverse ligament calcification. RESULTS: In a significant percentage of older individuals, some form of degenerative disease is present. These changes show a roughly linear progression with advancing age. CONCLUSION: Morphologic changes related to AO osteoarthritis are frequent coincidental findings in patients referred for CT examination of the brain or paranasal sinuses. Awareness of the appearance and prevalence of degenerative changes in the AO joint on CT is important because reports in the literature and earlier findings of the authors indicate that these changes can be a source of suboccipital headache.

Carbamyl phosphate synthetase-1 deficiency discovered after valproic acid-induced coma.

Valproic acid induced coma is presented in an adult patient without a history of metabolic disease. Liver biopsy revealed a reduction in activity of carbamyl phosphate synthetase-I, an enzyme obligated for transformation of ammonia to urea in the urea cycle. After recovery CT scan follow-up showed marked cerebral atrophy which did not exist prior to the state of coma. Risk factors are discussed.