Magnetic resonance imaging of a transient splenial lesion of the corpus callosum resolved within a week

The transient splenial lesion (TSL) of the corpus callosum (CC) is an uncommon radiologic finding incidentally detected on Magnetic Resonance Imaging (MRI).It was first observed in epileptic patients and ever since it has been described in varied neurologic conditions but its etiology is still little known. Slow disappearance of signal abnormalities in the CC mainly occurs after some weeks or months and then TSL carries a good prognosis making unnecessary invasive therapies and procedures. We report a case of an isolated TSL of CC in a patient suffering from psychotic and hormonal disorders, which spontaneously resolved within only one week.     

Isolated and Reversible Lesions of the Corpus Callosum: A Distinct Entity

The Reversible Splenial Lesion Syndrome represents a distinct clinicoradiological syndrome, associated with several disorders, including infection, high altitude cerebral edema, antiepileptic drug withdrawal, and severe metabolic disturbances (hypoglycemia and hypernatremia). Clinical presentation is nonspecific, most frequently as an encephalopathy or encephalitis. Outcome is favorable in most patients unless there is a severe underlying disorder. Magnetic resonance imaging findings are restricted to the splenium and consist of a nonenhancing oval lesion, hyperintense on T2-weighted images, including FLAIR. Findings on diffusion-weighted imaging are consistent with cytotoxic edema except for high-altitude cerebral edema, where vasogenic edema is present. Resolution after weeks or months is the rule.
J Neuroimaging 2010;20:1-2.     

汉字表征的中央凹分割：来自汉字左半错读患者的证据

摘要 目的：从认知神经心理学角度验证汉字的中央凹表征是分割的还是双重的。 方法：对1例脑梗死病灶累及左腹内侧枕颞区和胼胝体压部左侧导致右视野同向偏盲但保留右半中央凹视野的患者KY,进行一系列中央凹范围内的汉字朗读检查,包括：注视左右结构合体字中点的中央注视速视朗读,左右半中央凹视野的分视野速视朗读。 结果：KY对于注视合体字中点的汉字,朗读时出现左半错读现象,表现为左半部件的替代或遗漏。对于呈现在左、右半中央凹视野的汉字朗读,则出现左视野失读现象。 结论：中央凹内汉字的表征是分割的,即左中央凹内汉字信息仅在右枕表征,右中央凹内汉字仅在左枕表征。实验结果无法用中央凹双重表征理论解释。     

Anatomic variation of the corpus callosum in persons with gender dysphoria

Previous postmortem anatomical studies have demonstrated differences between male and female in the size and shape of the splenium of the corpus callosum. The current study using the magnetic resonance imager compares the corpus callosum in 20 transsexuals and 40 controls to determine if the anatomic variance is related to anatomic sex or gender identity. No statistical differences were found in the cross-sectional areas of the entire corpus callosum, regardless of genetic sex or gender. However, the genetic males did have a larger whole-brain cross-sectional area. Also, even though there was a wide range of differences in shape and size in the splenium, the study found no significant differences between the sexes or between transsexual patients of either sex and the controls.