Surgical management for IgG4-related ophthalmic disease by a transcranial biopsy combined with extraorbital decompression: illustrative case

Abstract

Background: Immunoglobulin G4-related ophthalmic disease (IgG4-ROD) accounts for 22% of Japanese lymphoproliferative orbital disease and occurs in 4%-34% of patients with IgG4-related disease, according to the largest case series published to date. Because the optic nerve mass often appears as a tumor-like lesion, it is important, although difficult, to differentiate IgG4-ROD from other orbital tumors and diseases, and biopsy is essential for diagnosis. Here, the authors describe the surgical management of an IgG4-ROD case.

Observations: A 63-year-old man presented to the authors' hospital with proptosis and visual impairment. Ophthalmic examination revealed intraocular hypertension. IgG4-related disease with an ophthalmic lesion was suspected on the basis of a blood test and imaging studies. Transcranial biopsy with extraorbital decompression was performed. The patient's symptoms, including visual impairment, improved 3 days after operation, and his IgG4-related disease resolved after corticosteroid treatment.

Lessons: The standard treatment for IgG4-related disease is systemic corticosteroid therapy. However, this treatment should not be administered to patients with IgG4-ROD who a high risk of blindness. In this case, the authors completed a diagnostic and symptom-relieving transcranial biopsy without affecting the patient's aesthetic characteristics. This is the first study, to our knowledge, to report extraorbital decompression via a transcranial approach as a surgical option for IgG4-ROD.

Keywords: FT = frontotemporal; IgG4-ROD = immunoglobulin G4–related ophthalmic disease; IgG4-related disease; IgG4-related ophthalmic diseases; LogMAR = logarithm of the minimum angle of resolution; MRI = magnetic resonance imaging; extraorbital decompression; orbital tumor; transcranial orbital approach.

FIG. 1.

MRI of the orbit. T1-weighted image with gadolinium contrast of the mass of the orbit and that of the enlarged lacrimal glands. A: Axial view. B: Saggital view. C: Coronal view.

FIG. 2.

A: Scheme of skin incision and temporal muscle incision. The skin incision began from the preauricular region at the level of the zygomatic arch. The curve of the incision was slightly (approximately 1 fingerbreadth) augmented posteriorly at the supra-auricular level to create space for the posterior retraction of the temporal muscle, and it was ended at 1–2 cm from the midline (red line). B: Scheme indicating the direction (arrows) of retraction of the skin flap and that of the temporal muscle. The cutaneous flap was reflected inferiorly. The muscle flap was incised along the linear temporalis, except for the posterior 3-fingerbreadth region (green line), and pushed posteriorly to expose the base of the temporal bone. Craniotomy was designed by creating 3 burr holes on the cranium (MacCarty’s keyhole, 1 hole posterior to the squamous suture on the level of the zygomatic root, and 1 hole inferior to the linear temporalis line; blue line). C: Scheme of the extraorbital decompression. The lateral and superior orbital walls were drilled off (blue highlighted area).

FIG. 3.

Postoperative bone computed tomography (CT). Comparison between pre- and postoperative axial CT images of bone (A). Lateral wall of the orbit is drilled off. Posterior view of three-dimensional bone image showing the lateral wall and orbital roof were removed (B).

FIG. 4.

Proptosis of the right eye (A) dramatically improved, as observed on MRI performed 3 days after operation (B). Equator line of the left eye is shown by the yellow lines.