2 Subependymal Giant Cell Astrocytoma

Case 2 Subependymal Giant Cell Astrocytoma

Remi Nader

Fig. 2.1 Magnetic resonance imaging (MRI) scan of the brain (A–C) with gadolinium intravenous contrast and (D) without contrast showing (A) pertinent axial, (B) coronal, and (C,D) sagittal sections.

Clinical Presentation

A 21-year-old man presents with 2-year history of headaches, exacerbated over the past 3 to 4 months.

He also complains of blurred vision intermittently and some episodes of nausea and vomiting.

Neurologic examination reveals bilateral papilledema; otherwise, no focal deficits are seen.

Upon further questioning, he claims he had a history of seizures as a child, but this resolved by the time he was 12 years old.

Magnetic resonance imaging (MRI) scan of the brain is ordered (Fig. 2.1).

Fig. 2.2 (A) Axial computed tomography (CT) scan without contrast at the level of the ventricles showing hyperdense lesions along the lateral walls of both ventricles. (B) Photograph of macular skin lesion with loss of pigmentation.

Fig. 2.3 Intraoperative pictures taken with microscope magnification (300×) showing the inside of the right lateral ventricle (A) with large fleshy mass superiorly representing the tumor. A small draining vein within the ventricle is pointed out (arrow). Following tumor resection, the picture is taken while inside the lateral ventricle showing the slitlike opening (arrowhead) into the third ventricle via the foramen of Monro (B). Picture taken while retracting with a self-retaining retractor and exposing the medial wall of the lateral ventricle (C).

Questions

Interpret the lesion on the MRI.

Give a differential diagnosis.

What further studies should you obtain?
A computed tomography (CT) scan of the brain is done and upon further examination, you observe the following skin lesions (multiple on his trunk and lower extremities) (Fig. 2.2).
Name the lesions seen on the CT and on the skin.
What is the diagnosis?
What other lesions are associated with the presenting diagnosis?
What are the operative options in this case?
Which option do you choose and why?
What preoperative studies would you like to obtain?
You elect to perform a right transcallosal approach. As you enter the right ventricle, you see the tumor anterior to your corpus callosal opening and the falx laterally. Identify the following vessel (Fig. 2.3A, arrow) and name the parent or immediate tributary vessel.
As you start dissecting the tumor, cerebrospinal fluid (CSF) is let out and the septum pellucidum bulges out and obstructs your view. What is your course of action?
You perform a complete resection. The tumor was seen to extend in the 3 rd ventricle, shown in Fig. 2.3B. It was attached on the structure inside the lateral ventricle as shown in Fig. 2.3B (arrowhead). Identify this structure and give the function of this structure.