case_images: PMC11291257_01
case_images: Humphrey visual field test pre-operatively, post-operatively, and 3 months post-operatively. (A) Pre-operative visual field test showing an enlarged blind spot bi-temporally (gray-to-dark region), (B) post-operative visual field test showing mild improvement in visual field defect compared to the pre-operative visual field test, and (C) a 3-month post-operative visual field test showing further improvement of the visual field.
case_images: fsurg-11-1399163-g001.jpg
case_images: PMC11291257_01_fsurg-11-1399163-g001.jpg
case_images: F1
case_images: Humphry visual field examination demonstrated an asymmetrically enlarged blind spot bilaterally (Figure 1A). A follow-up visual field examination 1 week after the surgery showed improvement compared to the pre-operative visual field (Figure 1B). Visual field examination demonstrated further improvement in bilateral visual fields, with a reduced size of blind spots (Figure 1C).
case_images: Pre- and post-operative MRI images and the magnified view of the optic chiasm in coronal and axial views. Pre-operative images (A)-(C) show a large extra-axial hypervascular tumor measuring 6.1 cm x 4.3 cm at the right temporoparietal convexity, causing a significant mass effect with a 1.3 cm leftward midline shift, uncal herniation, and midbrain compression. In the coronal view (B), the stalk and pituitary gland (arrowhead) are deviated to the left and forced against the optic chiasm, which is thicker. The edematous nerve fibers on the temporal side of the right optic nerve and the nasal side of the left just-decussated fibers can be clearly seen in the T2-weighted FLAIR MRI image, as shown in the circle in (C). Post-operative images (D)-(F) show no tumor and normalization of midline structures. The optic chiasm and pituitary stalk (arrowhead), as well as the third ventricle and hypothalamus, all remain in the central position and have no compressive effect (E). There is no edema along the optic chiasm to tract on pre- and post-chiasmatic nerve fibers, as shown in the circle in (F).
case_images: fsurg-11-1399163-g002.jpg
case_images: PMC11291257_01_fsurg-11-1399163-g002.jpg
case_images: F2
case_images: A T1-weighted contrast-enhanced MRI revealed a large extra-axial hypervascular tumor measuring 6.1 cm x 4.3 cm at the right temporoparietal convexity, causing significant mass effect with a 1.3 cm leftward midline shift, uncal herniation, and midbrain compression, indicative of significant IICP (Figure 2). In addition, the pituitary stalk was deviated to the left, causing focal indentation on the just-decussated nasal fibers of the optic chiasm (Figure 2C). A 3-month MRI scan indicated complete removal of the tumor with normalization of the compressive effects on the optic apparatus (Figures 2D-F).
case_images: Illustration of right temporal optic nerve fiber stretching and pituitary stalk indentation on the right just-decussated nasal fibers. The large right parietal meningioma is pushing the optic apparatus to the left, causing the right optic nerve to stretch. The pituitary stalk is also pushed to the left, indenting on the optic chiasm. The stretched right optic nerve and the compressed optic chiasm show signs of injury, and we can see edematous changes on the MRI T2-weighted image. The edematous area is illustrated in yellow. The right temporal optic nerve fibers and the just-decussated right nasal optic fibers are injured, and together, they demonstrate clinically atypical visual field defects.
case_images: fsurg-11-1399163-g003.jpg
case_images: PMC11291257_01_fsurg-11-1399163-g003.jpg
case_images: F3
case_images: An illustrated image is shown in Figure 3.