Intracranial dermoid cysts: variations of radiological and clinical features

BACKGROUND: Intracranial dermoid cysts are uncommon, and their clinical features as well as surgical management differ from patient to patient. Dermoids are generally benign lesions, but may cause spontaneous complications such as meningitis and/or hydrocephalus due to rupture and epileptic seizures depending on their location. Little has been reported about characteristic imaging findings with resulting therapeutic considerations, and only a few reports exist about associated hydrocephalus. Imaging modalities have changed and can facilitate differential diagnosis and follow-up if applied correctly. In this paper, we attempt to contribute our clinical experience with the management of dermoid cysts. PATIENTS AND METHODS: The charts of five men and two women with intracranial dermoid cysts were retrospectively reviewed. The patients were treated between September 1993 and September 2006. Selected patients are presented in detail. RESULTS: Tumour location, size and radiographic characteristics varied in each patient. Clinical presentations comprised focal neurological deficits as well as epileptic seizures, persistent headache, mental changes and psycho-organic syndromes. One patient underwent delayed ventriculo-peritoneal shunting after ruptured fatty particles caused obstructive hydrocephalus. Despite dermoid rupture into the subarachnoid space, three patients never developed hydrocephalus. Diffuse vascular supra-tentorial lesions were seen in one patient as a result of aseptic meningitis. Diffusion-weighted imaging (DWI) hyperintensity in dermoids is related to decrease of water proton diffusion and should be used for both the diagnosis and follow-up of this lesion. CONCLUSION: Although dermoid cysts are known to be benign entities per se, their rupture can cause a wide range of symptoms including aseptic meningitis and/or hydrocephalus. This may be due to intraventricular obstruction and/or paraventricular compression. While rupture does not necessarily bring about hydrocephalus, radical removal of the tumour and close monitoring of ventricular size is required. Although not widely recognised as such, DWI is considered to be a useful imaging modality in the diagnosis and follow-up of dermoids

Differences and similarities in the serotonergic diathesis for suicide attempts and mood disorders: a 22-year longitudinal gene–environment study

To investigate similarities and differences in the serotonergic diathesis for mood disorders and suicide attempts, we conducted a study in a cohort followed longitudinally for 22 years. A total of 1255 members of this cohort, which is representative of the French-speaking population of Quebec, were investigated. Main outcome measures included (1) mood disorders (bipolar disorder and major depression) and suicide attempts by early adulthood; (2) odds ratios and probabilities associated with 143 single nucleotide polymorphisms in 11 serotonergic genes, acting directly or as moderators in gene–environment interactions with childhood sexual or childhood physical abuse (CPA), and in gene–gene interactions; (3) regression coefficients for putative endophenotypes for mood disorders (childhood anxiousness) and suicide attempts (childhood disruptiveness). Five genes showed significant adjusted effects (HTR2A, TPH1, HTR5A, SLC6A4 and HTR1A). Of these, HTR2A variation influenced both suicide attempts and mood disorders, although through different mechanisms. In suicide attempts, HTR2A variants (rs6561333, rs7997012 and rs1885884) were involved through interactions with histories of sexual and physical abuse whereas in mood disorders through one main effect (rs9316235). In terms of phenotype-specific contributions, TPH1 variation (rs10488683) was relevant only in the diathesis for suicide attempts. Three genes contributed exclusively to mood disorders, one through a main effect (HTR5A (rs1657268)) and two through gene–environment interactions with CPA (HTR1A (rs878567) and SLC6A4 (rs3794808)). Childhood anxiousness did not mediate the effects of HTR2A and HTR5A on mood disorders, nor did childhood disruptiveness mediate the effects of TPH1 on suicide attempts. Of the serotonergic genes implicated in mood disorders and suicidal behaviors, four exhibited phenotype-specific effects, suggesting that despite their high concordance and common genetic determinants, suicide attempts and mood disorders may also have partially independent etiological pathways. To identify where these pathways diverge, we need to understand the differential, phenotype-specific gene–environment interactions such as the ones observed in the present study, using suitably powered samples