Abril - 2017

uschel

308

ssoc

ras

2017; 63(4):307-310

FIGURE 1

A. Wormian bones in a brachycephalic skull. B. Skull base abnormality. C. Basilar invagination obliterating the prepontine

subarachnoid space, with compression of the brainstem. D. FIESTA image depicting the cisternal portion of the left trigeminal nerve.

Magnetic resonance imaging (MRI) revealed basal

angle (Welcker) enlargement and clivus almost parallel to

the palate, denoting platybasia. Remarkable basilar in-

vagination was present, with odontoid process projecting

17 mm and 27 mm above the Chamberlain’s line and the

McGregor’s line, respectively. Significant dorsal insinua-

tion of odontoid process was found occluding pre-pontine

subarachnoid space and compressing the pontine-medul-

lary junction (Figure 1). No mass lesions or contrast en-

hancement over the fifth cranial nerves were seen.

Cranial-CT scan showed brachycephalic skull, with

thin and irregular skull cap. Both foramina ovale showed

irregular shape and reduced diameter.

The procedure was performed using angiography

suite, allowing easier visualization of the foramen ovale.

Under light sedation and with the patient in supine posi-

tion, with slight neck extension, the X-ray intensifier was

positioned on submental view to obtain the images fol-

lowed by 3D CT-scan in the angiography suite. A #15

gauge cannula was inserted and positioned at the foramen

ovale prior to a #4 Fogarty embolectomy catheter. The

X-ray intensifier was displaced to lateral view and inflation

was performed (1.0 mL of radiopaque dye). A pear-shaped

image was obtained and the patient developed transitory

bradycardia response. Position was confirmed with 3D

CT-scan (Figure 2), balloon was deflated, process was

repeated twice for 3 inflations (20 seconds/each, total 60

seconds) (Figure 3). No neuronavigation system, Mayfield

clamps, frames or stereotactic devices were used.

Post-procedure, the patient reported painless hypo-

esthesia on left V1, V2 and V3 segments. She was discharged

pain-free on the same day, with instructions to maintain

the medication dosage until her first medical appointment.

After one year of follow-up, the patient no longer com-

plained of pain and ceased taking all medication.

iscussion

OI can be characterized by bone fragility secondary to

reduced bone mass.

2,3

Fortunately, this clinically and ge-

netically heterogeneous group of heritable disorders is