Technical modification in the intracarotid chemotherapy and osmotic blood-brain barrier disruption procedure to prevent the relapse of carboplatin-induced orbital pseudotumor.

The blood-brain barrier disruption (BBBD) procedure is an established strategy to enhance drug delivery to brain tumors. Complication rates associated with this procedure are usually low, but when complications do occur, they usually mandate discontinuation of treatment. Orbital pseudotumor is an inflammatory condition of one or more extraocular muscles that produces limitation of ocular motility. Patients usually experience sudden diplopia associated with orbital pain, conjunctival chemosis and injection, and proptosis. Imaging of the orbit shows diffuse enlargement of the extraocular muscles, exophthalmia, and, rarely, sinusal or intracranial infiltration. On pathologic examinations, the soft tissues of the orbit are infiltrated with a mixture of eosinophils, lymphocytes, and plasma cells. Many etiologies can induce this syndrome, including the intracarotid infusion of platinum molecules. As part of a phase II study, a total of 110 patients were treated for malignant brain tumors with intra-arterial carboplatin, enhanced by the BBBD procedure, at the Sherbrooke University Hospital. Here we report on three patients who developed orbital pseudotumor ipsilateral to the carotid infused a few hours to days after the procedure. After the occurrence of this syndrome in the first patient, we developed a technical modification to the procedure that enabled uninterrupted treatment in the other two patients. This modification was as follows: after the mannitol infusion, and before carboplatin, the catheter was changed for a 3.5 tracker and was repositioned just above the emergence of the ophthalmic artery.