Brain MRI findings in infants with primary congenital glaucoma

Abstract

Background: Congenital glaucoma appears in the first months of life, eventually at birth. Isolated congenital glaucoma is characterized by minor malformations of the irido-corneal angle of the anterior chamber of the eye. Clinical manifestations include tearing, photophobia and enlargement of the globe appearing in the first months of life. Imaging technology such as optical coherence tomography and measurement of central corneal thickness may play an important role in the assessment of children with suspected or known glaucoma. However, no MRI findings of the CNS in patients with primary congenital glaucoma (PCG) were reported in the literature. The purpose of this study was to investigate MRI findings of the brain in infants with PCG.

Methods: We reviewed the radiological, histopathological and clinical characteristics of infants with primary congenital glaucoma. The records of 17 patients with PCG were reviewed and the MRIs of the brain and associated manifestations were analyzed.

Results: Three patients with PCG had abnormal MRI findings suggesting agenesis of the corpus callosum. Two infants had delayed myelinization of the brain.

Discussion: Significant abnormal optic nerve excavation and increased corneal diameters in 2 patients with delayed myelinization may suggest that intraocular pressure can be more striking and more severe, revealing a close relationship with PCG and abnormal myelinization in the white matter. Studies with more patients are needed to confirm these results.

Figure 1

Midline saggittal T-1 weighted MR images showing the medial hemispheric sulci coursing all the way in a radial fashion. The trigones, occipital horns and temporal horns of the lateral ventricles are variably dilated as a result of the agenesis of the corpus callosum.

Figure 2

Axial T-1 MRI demonstrating parallel prominent lateral ventricles, which are a typical finding for agenesis of the corpus callosum. The midline saggital T-1 weighted images show that the frontal horns are vertically oriented. The third ventricle is continuous with the interhemispheric fissure and extends somewhat higher than normal between the lateral ventricle.

Figure 3

The midline saggittal T-1 weighted MR image is quite characteristic in patients with agenesis of the corpus callosum. Axial T-1 demonstrates enlarged posterior horns and lateral ventricles in parallel alignment. The posterior horns have a characteristic shape that has been described as being similar to the wings of a bird. The third ventricle is continuous with the interhemisperic fissure both superiorly and anteriorly. The lateral ventricles tend to be parallel instead of showing their normal lateral position

Figure 4

T-2 weighted MRI of 6 month old infant shows rostral progression of the maturation of the internal capsule. The anterior limbs of the anterior capsule are not well myelinated. Isointensity of the cortical gray matter and subcortical white matter, resulting in difficulty in the identification of structural abnormalities at this age suggest delayed myelinization of the white matter.

Figure 5

Axial T-2 weighted MRI of a 3-month-old infant showing low signal intensity in the posterior aspect of the posterior limb of the internal capsule, the ventrolateral thalamus and the perirolandic gyri of the cortex. Some low signal peripheral to the frontal horns of the lateral ventricle represent residual germinal matrix. The T-2 weighted images correspond more closely to the MRI of a 1-month-old infant.