Is silicone oil optic neuropathy caused by high intraocular pressure alone? A semi-biological model

Retrospective review of 50 eyes with long-term silicone oil tamponade for more than 12 months

“…In the remaining patients, it was secondary to it and not related to high IOPs, with one exception where mean IOP was 34 mmHg. This finding is consistent with post mortem models which show that SOassociated optic neuropathy is not pressure-related [20]. The latest observed optic neuropathy was 49 months after SO intraocular insertion (average 19 months, Fig.…”

Intraventricular migration of silicone oil: A mimic of traumatic and neoplastic pathology

“…Another hypothesis by Fangtian et al posits that deep cupping of the optic disc from chronically increased intraocular pressure allows silicone oil to directly enter the subarachnoid space by breaking through the cerebral pia [10]. Another hypothesis by Knecht et al suggests that active physiologic processes facilitate silicone oil migration [1]. A final hypothesis is that silicone oil migration occurs in patients with anatomic variants such as an optic pit or coloboma [11].…”

“…Silicone oil is a commonly employed method for intraocular endotamponade of complicated retinal detachments [1]. Typically, 1000-5000 centistroke-viscosity silicone oil is used to treat retinal detachments associated with proliferative retinopathy, giant retinal tears, cytomegalovirus infection and trauma [2].…”

Is There a Role for Long-Term Silicone Oil Tamponade for More than Twelve Months in Vitreoretinal Surgery?

“…The mechanism may be similar to the migration of acid mucopolysaccharides from the vitreous into the optic nerve in non-vitrectomised eyes with markedly elevated IOP (Schnabel’s cavernous optic nerve atrophy). In a study on postmortem eyes, however, Knecht et al [53] could not establish a pressure-related connection.…”