A child presents with raised ICT. On CT scan a lesion is seen around foramen of monro with multiple periventricular calcific foci. What could be probable diagnosis:
**Core Concept**
Tuberous sclerosis complex (TSC) is a genetic disorder characterized by the growth of numerous non-cancerous (benign) tumors in various parts of the body, including the brain. These tumors can cause increased intracranial pressure (ICT) due to their location and size.
**Why the Correct Answer is Right**
The characteristic imaging findings in TSC include subependymal nodules, which are typically located around the foramen of Monro, and subependymal giant cell astrocytomas (SEGA). The presence of multiple periventricular calcific foci is also a hallmark of this condition. These calcifications are often seen in the cerebral cortex, basal ganglia, and cerebellum. TSC is caused by mutations in either the TSC1 or TSC2 gene, which encode for the proteins hamartin and tuberin, respectively.
**Why Each Wrong Option is Incorrect**
**Option A:** Sturge-Weber syndrome is a different neurocutaneous disorder characterized by a port-wine stain on the face, leptomeningeal angiomatosis, and calcifications in the cortex. While it can cause increased ICT, the imaging findings are distinct from those seen in TSC.
**Option B:** Neurofibromatosis type 1 (NF1) is another neurocutaneous disorder that can cause increased ICT due to optic gliomas and other tumors. However, NF1 is typically associated with cafe-au-lait spots, axillary freckling, and Lisch nodules, rather than periventricular calcifications.
**Option C:** Dandy-Walker malformation is a congenital disorder characterized by an enlarged fourth ventricle, hypoplasia of the cerebellum, and a cystic dilation of the fourth ventricle. While it can cause increased ICT, the imaging findings are distinct from those seen in TSC.
**Option D:** Medulloblastoma is a malignant brain tumor that can cause increased ICT, but it typically presents with a large posterior fossa tumor and hydrocephalus, rather than periventricular calcifications.
**Clinical Pearl / High-Yield Fact**
Tuberous sclerosis complex can be diagnosed by the combination of clinical features, imaging findings, and genetic testing. The "ash leaf spots" seen in TSC are a classic dermatological finding, and the "shaggy mouse" hair seen in this condition is a distinctive clinical feature.
**Correct Answer: C. Tuberous sclerosis complex.**