Entrapment neuropathy of the optic nerve due to hyperostosis associated with congenital anemia

Abstract

The authors report on the case of a 14-year-old boy who presented with bilateral visual impairment due to optic canal stenosis caused by hyperplasia of the bone marrow arising from anemia. The patient had hereditary hemolytic anemia with unstable hemoglobin of the Christchurch type. This congenital form of anemia caused hyperplasia of the bone marrow as well as hyperostosis of the entire calvarial bone, which in turn led to optic canal stenosis. The patient underwent surgical decompression of the optic canal, resulting in significant improvement in visual acuity. Pathological findings in the calvarial bone indicated hypertrophic bone marrow with no other specific features such as neoplastic pattern or fibrous dysplasia. With the exception of objective hearing impairment, no other significant cranial neuropathy has been detected thus far. On reviewing the published literature, this case was found to be the first in which hyperostosis due to congenital anemia resulted in symptomatic entrapment neuropathy of the optic nerve. The authors concluded that surgical decompression effectively improves visual acuity.

Cribra orbitalia is a vascular phenomenon unrelated to marrow hyperplasia or anemia: Paradigm shift for cribra orbitalia

“…The quasi‐linear, reticulated bone accretion pattern (Figure 1b) is quite different from the continuous elevated periosteum produced by the subperiosteal hemorrhage related to vitamin C deficiency (Barlow, 1883). Baba, Minamida, Mikami, Koyanagi, and Houkin (2005) reported optic nerve entrapment by anemia‐related hyperostosis, but no such changes were noted among the anemic individuals examined in this study (Baba et al, 2005). Bone accretion in hypervitaminosis A is actually enthesial in distribution (Arena, Sarazen, & Baylin, 1951; Rothschild & Martin, 2006; Seawright, English, & Gartner, 1965) and is not known to affect the orbit.…”

Electrophysiological assessment of nutritional optic neuropathy: a case report

“…Vitamin A deficiency has been shown to inhibit the mobilisation of iron stores in tissues [ 15 ] and thus may contribute to the patient’s long history of iron deficiency anaemia. Interestingly, there has been a report of optic canal stenosis associated with congenital haemolytic anaemia [ 16 ]. Although vitamin B12 deficiency rarely manifests visual symptoms, it can cause bilateral optic neuropathy and optic atrophy, which is typically symmetrical [ 17 ].…”

Cribra orbitalia: Dissecting an ill‐defined phenomenon

“…Porotic hyperostosis has been repeatedly reported in clinical cases of anaemia (Cooley, Witwer, & Lee, ), in sickle cell anaemia (Diggs, Pulliam, & King, ), and haemolytic anaemia (McAfee, ) but only very rarely in chronic iron deficiency anaemia (Eng, ). Baba, Minamida, Mikami, Koyanagi, and Houkin () reported a clinical case of congenital anaemia with porotic hyperostosis present along with cribra orbitalia expressed only as simple porosity on computerised tomography scan. Porotic hyperostosis is thought to reflect marrow expansion of the diploe in affected bones.…”