4 Stages in neurocysticercosis
1. Viable or Vesicular stage
2. Colloid satage
3. Nodular - Granular stage
4. Cacified cyst stage
CT Findings
Vesicular stage : Small and rounded low-density areas that are well demarcated from the surrounding brain parenchyma. These lack edema as there is supression of host's immune response by the living tenia in the cyst. the scolex in the cyst appears as an eccentric hyperdense nodule
Colloid satage: (So-called ‘acute encephalitic phase’ of neurocysticercosis ). Seen as ill defined lesions surrounded by edema. ( Dead Tenia) iniitiating host response to form edema. Ring enhancement with contrast.
Nodular - Granular stage: Nodular hyperdense lesions surrounded edema after contrast.
Calcified Stage : Hyperdense areas without any edema surrounding
MRI Characteristics :
Vesicular stage : Cysts with csf intensity in both T1 and T2 images and scolex in the cyst as a high intensity in the cyst eccentrically. ( Hole with dot imaging)
Colloid Stage: The wall of the cyst becomes thick and hypointense and there is marked perile-
sional edema; these findings are better visualized on T2-weighted images
Nodular - Granular stage: Granular cysticerci are visualized as areas of signal void on both T1- and T2-weighted images surrounded by edema or gliosis with hyperintense rims around the area of signal void
Calcified Stage : These lesions are usually not visualized with MRI ( Usually hypointnse on all the sequences)
