From the Research
To diagnose drooping of the corpus callosum splenium, magnetic resonance imaging (MRI) is the preferred radiological method, particularly with the use of diffusion tensor imaging as shown in a recent study 1. The diagnosis requires obtaining sagittal T1-weighted images of the brain, which provide excellent anatomical detail of the corpus callosum. When evaluating for splenial drooping, radiologists should look for an abnormal downward displacement of the posterior portion (splenium) of the corpus callosum. This can be assessed by measuring the angle formed between the inferior border of the splenium and a horizontal reference line, or by comparing the position of the splenium relative to other midline structures. Some key points to consider when evaluating the splenium include:
- Normal variants must be distinguished from pathological drooping, which may be associated with conditions like Chiari malformation, intracranial hypotension, or mass effect from adjacent lesions.
- Additional sequences such as T2-weighted images, FLAIR, and diffusion-weighted imaging should be included to evaluate for associated abnormalities, as seen in studies 2, 3.
- Contrast administration with gadolinium may be necessary if underlying pathology is suspected.
- The radiological assessment should include evaluation of ventricular size, position of the cerebellar tonsils, and any evidence of brain herniation patterns, as these findings often accompany significant splenial drooping. It's also important to consider the clinical context and potential underlying conditions, such as Alzheimer's disease or mild cognitive impairment, which can affect the splenium 1, or other conditions like hydrocephalus and dysgenesis of the corpus callosum 4. In pediatric cases, a range of conditions can involve the splenium, and familiarity with these can assist in formulating a differential diagnosis 5.