The Bone Does Not Predict the Brain in Sturge-Weber Syndrome

Abstract

Background and purpose: It has been hypothesized that skull marrow signal alteration may represent an early disease manifestation of Sturge-Weber syndrome before development of its intracranial manifestations. We alternatively hypothesized that intraosseous changes are associated with the overlying port-wine stain rather than the intracranial stigmata of Sturge-Weber syndrome and hence are not a predictor of brain involvement.

Materials and methods: MR imaging of children presenting with port-wine stain and/or Sturge-Weber syndrome between 1998 and 2017 was evaluated by 2 pediatric neuroradiologists for marrow signal abnormality and pial angioma and other Sturge-Weber syndrome features: ocular hemangioma, atrophy, and white matter changes (advanced myelination). Groups were divided into port-wine stain-only (without intracranial Sturge-Weber syndrome features) and Sturge-Weber syndrome (the presence of cerebral pial angioma). The χ² test was performed to evaluate the association between port-wine stain and bone marrow changes and between osseous change and pial angioma.

Results: We reviewed 139 cases: 40 with port-wine stain-only and 99 with Sturge-Weber syndrome with pial angioma. Fifteen of 99 cases of Sturge-Weber syndrome had no port-wine stain. In the port-wine stain-only cohort, 78% had ipsilateral bony changes and 17% had no intraosseous changes. In the Sturge-Weber syndrome cohort, 84/99 had associated port-wine stain, 91% (P < .01) had bony changes ipsilateral to the port-wine stain or had no bone changes in the absence of port-wine stain, and 77% (P = .27) had bony changes ipsilateral to a cerebral pial angioma. Eighty percent of patients with Sturge-Weber syndrome who lacked a port-wine stain also lacked marrow changes. Five patients with bilateral port-wine stain and bilateral marrow changes had only a unilateral pial angioma.

Conclusions: Intraosseous marrow changes are strongly associated with facial port-wine stain; no significant association was found between pial angioma and bone marrow changes.

Fig 1.

Associated findings of SWS. A 4-month-old boy with SWS. A, Postcontrast T1WI of the orbits shows a left ocular choroidal hemangioma (clinically confirmed). B, Coronal T2WI of the brain reveals volume loss of the left hemisphere with associated accelerated myelination (arrow). C, Postcontrast axial T1WI of the brain shows an enlarged and enhancing left glomus angioma (arrow) and prominent transmedullary veins (circle).

Fig 2.

Calvarial bone marrow abnormality. A 6-month-old boy with right PWS only. A, Axial T2-weighted STIR shows high-signal abnormality in the right calvaria (arrows). B, Graphic of a child with right-sided PWS. Reproduced with permission from Scio21/Bigstock.com.

Fig 3.

Bilateral PWS with bilateral calvarial marrow abnormality. An 8-month-old boy with SWS. Axial T2-weighted-STIR (A) and axial T1-weighted postcontrast (B) images reveal a bilateral marrow T2 high-signal calvarial abnormality and enhancement. C, Axial T1WI postcontrast shows a left-sided temporo-occipital pial angioma. Coronal T1-weighted precontrast (D) and postcontrast (E) imaging show bilateral marrow and dural enhancement.

Fig 4.

SWS with absent PWS. An 8-month-old girl with SWS. A, Axial T2-weighted STIR shows left temporo-occipital calvarial thinning with no bone marrow abnormality. B, Axial postcontrast T1WI shows a corresponding thick enhancing left hemispheric pial angioma.

Fig 5.

The interpeduncular cistern sign. Upper panel, a 9-month-old boy with SWS. A and B, Postcontrast axial T1WI shows a left-sided unilateral pial angioma and a zoomed-in view of the interpeduncular cistern confirming the unilaterality (arrow). Lower panel, a 10-month-old girl with SWS. C and D, Bilateral pial angiomas with a zoomed-in view confirming the bilaterality (arrows), positive for the “warning sign of Warne-Mankad.”

Fig 6.

“Warning sign of Warne-Mankad.” Bilateral interpeduncular cistern enhancement. A 10-month-old girl with SWS and bilateral PWS. A, Axial T2-weighted STIR shows bilateral hemispheric volume loss. B, Axial postcontrast T1WI shows a right-frontal and left-hemispheric pial angioma with the warning sign confirming the bilateral interpeduncular cistern enhancement (C). Coronal T2-weighted STIR (D) shows bilateral calvarial high signal and marrow enhancement (E). Coronal postcontrast FLAIR image (F) shows bilateral marrow enhancement and left-sided dural thickening.

Fig 7.

Schematic illustration of the major calvarial diploic venous channel routes over the skull. Reproduced with permission from Springer Nature (Tsutsumi et al¹⁶). MMV indicates middle meningeal vein; OC, occipitocervical route; OFO, orbital part of the fronto-orbital route; OP, occipitoparietal route; PFO, pterional part of the fronto-orbital route; PFP, pteriofrontparietal route; PP, pterygoid plexus; SS, sigmoid sinus; SSS, superior sagittal sinus; TS, transverse sinus.