Copyright 2008 The Authors Journal compilation 2008 Blackwell Munksgaard
Acta Neurol Scand 2008: 118: 251–255 DOI: 10.1111/j.1600-0404.2008.01007.x
ACTA NEUROLOGICA SCANDINAVICA
Asymptomatic idiopathic intracranial hypertension in children Bassan H, Berkner L, Stolovitch C, Kesler A. Asymptomatic idiopathic intracranial hypertension in children. Acta Neurol Scand 2008: 118: 251–255. 2008 The Authors Journal compilation 2008 Blackwell Munksgaard. Objective – To define characteristics of pediatric asymptomatic idiopathic intracranial hypertension (IIH). Patients and methods – We retrospectively reviewed our Neuro-Ophthalmology database (2000– 2006) for all cases of symptomatic and asymptomatic pediatric IIH. Results – Out of 45 IIH cases, 14 (31.1%) were asymptomatic (incidental examination). When compared with children with symptomatic IIH, asymptomatic cases were younger [5.6 (1.8–15) vs 11.0 (5–17) years, P = 0.007], had lower percentage of obesity (14.3% vs 48.4%, P = 0.046), and had male predominance (71.4% vs 38.7%, P = 0.06). Asymptomatic cases required shorter duration of acetazolamide treatment [3 (0–8), vs 6 (0–20) months, P = 0.021], and resulted in complete resolution of swollen discs. Conclusions – We speculate that asymptomatic IIH may be more common in young children and could represent a milder form or a presymptomatic phase before evolving into classic symptomatic IIH. Further studies to assess the clinical significance of asymptomatic IIH are warranted.
Introduction
Idiopathic intracranial hypertension (IIH) or pseudotumor cerebri is characterized by increased intracranial pressure (ICP) with no identifiable cause. A diagnosis of IIH is made according to the modified Dandy criteria (Table 1). Prior studies have noted that the clinical profile of pediatric IIH differs from the adult type, and suggested that the precipitating factors may be different in children (1–3). The male ⁄ female ratio for IIH in prepubescent children is essentially equal (4) and the distinct female predominance starts only at puberty (1, 5). While recent weight gain and obesity are more prevalent in post-pubertal IIH (6), younger children with IIH are less likely to be obese (7–9). It is generally assumed that any substantial increase in ICP will be expressed clinically. However, IIH can be incidentally detected in asymptomatic adults (10–13) and children (14, 15). It is not known whether asymptomatic individuals represent a variant of the disease, a milder clinical form, or to what extent they share the clinical and demographic characteristics as those exhibited in
H. Bassan1, L. Berkner2, C. Stolovitch2, A. Kesler2 1
Pediatric Neurology Unit, ÔDanaÕ ChildrenÕs Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel; 2 Neuro-Ophthalmology Unit, Department of Ophthalmology, Tel Aviv Sourasky Medical Center, and Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
Key words: acetazolamide; asymptomatic; idiopathic intracranial hypertension; lumbar puncture; obesity; pseudotumor cerebri Anat Kesler, MD, Neuro-Ophthalmology Unit, Department of Ophthalmology, Tel Aviv Sourasky Medical Center, 6 Weizmann Street, Tel Aviv 64239, Israel Tel.: +972 3 6973868 Fax: +972 3 9340520 e-mail:
[email protected] Haim Bassan and Lior Berkner contributed equally to this work. Accepted for publication February 1, 2008
the symptomatic group. In this study, we identified a group of children with asymptomatic IIH who were referred to our unit following an incidental diagnosis of papilledema during routine eye examination. The aim of the current study was to define the clinical characteristics of these children with asymptomatic IIH and compare them to children with symptomatic IIH. Patients and methods
In this retrospective study, we searched the database of the Neuro-Ophthalmology and the Pediatric Ophthalmology Units of our medical center for all patients diagnosed with IIH between January 2000 and November 2006. All IIH cases were originally diagnosed and followed by a single experienced Neuro-Ophthalmologist (AK). Inclusion criteria were: (i) age 200 mm H2O [although there are no valid, age dependent, ICP values in children, it is commonly accepted that ICP values of >200 mm H2O are defined abnormal (16–18)]; (iii) normal cerebrospinal fluid (CSF), cytological and chemical 251
Bassan et al. Table 1 Dandy criteria for idiopathic intracranial hypertension, modified for children Symptoms of increased ICP (headaches, nausea, vomiting, transient visual obscuration) Papilledema No localizing findings in neurological examination (except for false localizing signs such as abducens or facial palsies) Awake and alert patient Normal computed tomographic ⁄ magnetic resonance imaging findings without evidence of dural sinus thrombosis ICP >200 mm H2O* with normal cerebrospinal fluid, cytological and chemical findings No other detected cause of increased intracranial pressure Adapted from (20). *ICP values >200 mm H20 were defined abnormal for the pediatric population (see Methods) (16–18).
findings; (iv) normal neurological examination; (v) awake and alert condition; and (vi) no evidence of a space-occupying lesion, hydrocephalus, or sinus vein thrombosis on brain imaging. We then categorized the cases into asymptomatic (having no symptoms attributable to increased ICP, e.g. headaches, diplopia, irritability, apathy, visual obscurations, torticollis, etc.) and symptomatic according to the modified Dandy criteria (Table 1). Data on selected demographics, associated illnesses, medications in current use, clinical symptoms, best-corrected visual acuity (standard Snellen charts or by fixation behavior for very
small children, such as central steady maintained), and neurological and ophthalmological findings at the time of presentation were retrieved from the medical records. Spinal tap was performed in a lateral decubitus position and under sedation in all patients. Opening pressure, CSF fluid analysis, brain imaging reports, administration and duration of acetazolamide treatment, and ophthalmologic follow-up were also recorded. We could not obtain height information and therefore BMI could not be calculated. Therefore, weight was presented in percentiles for age and obesity was defined as weight above 97th percentile for age (19). We defined complete resolution of IIH as normal appearance of the optic discs and resolution of symptoms in the symptomatic cases. This study was approved by the institutional review board of Tel Aviv Sourasky Medical Center. Statistical analysis
Comparisons between asymptomatic and symptomatic IIH were made using the StudentÕs twotailed t-test for continuous variables and the FisherÕs exact test for dichotomous variables. To determine the independent effect of several variables, a multivariate model was constructed by logistic regression analysis. SPSS (SPSS-14, Inc, Chicago, IL, USA) was used for all statistical computations.
Table 2 Demographics and clinical characteristics of children with asymptomatic idiopathic intracranial hypertension
No.
Age (years)
Sex
Weight percentile
VA
300
6 ⁄6
2 2 3 4 4 6 3 1 8
1
15
M
2 3 4 5 6 7 8 9
13 14 13 2 2 4 2.5 5
F M F M M M M M
95 >97 50 >97 50–75
