Table 1: Geometrical descriptions adopted in 3D physiological models of drug delivery to the PSE.
Reference | Year | Dimension & species | Anatomical structures | Boundary conditions on external surfaces | Interface conditions |
[16] IV implant | 2005 | 3D rabbit | lens, vitreous, hyaloid surface, lumped posterior membrane (combined retina-choroid-sclera) | null drug concentration at the outer boundary of the lumped posterior membrane to model choriocapillary clearance, prescribed drug flux at the hyaloid membrane to represent drug clearance to the anterior region, drug mass flux on the surface of the implant | continuity of drug concentration at vitreous/posterior membrane |
[21] IV injection, IV implant | 2005 | 3D rabbit | anterior (posterior and anterior chamber, iris, ciliary processes, hyaloid membrane, Schlemm's canal, cornea, lens) and posterior (vitreous, retina-choroid, sclera) segments of the eye | given aqueous flux from ciliary processes, retina/choroid, aqueous Schlemm's canal; zero drug concentration at the outer boundary of the posterior membrane to model choriocapillary clearance, null flux at the Schlemm's canal and for symmetry at iris, lens and cornea | continuity condition of drug concentration |
[18] periocular/IV inj | 2007 | 1D mouse, human | periocular muscles/connective tissue, episcleral potential space, sclera, choroid, retina | zero-flux condition at the external boundary of periocular tissues; zero drug concentration at the retina/vitreous boundary (for periocular injection) and prescribed concentration at the retina/vitreous boundary (for IV injection) | porous jump across membranes with partition coefficient |
[13] systemic, episcleral | 2008 | 3D human | vitreous, retina, choroid/sclera | no flux of aqueous and drug through the lens; fluid pressure equal to IOP at hyaloid and to episcleral veins pressure at sclera, imposed drug outward flux at hyaloid and sclera | continuity of flow velocity and drug flux/concentration |
[15] IV injection | 2012 | 3D human, monkey, rabbit | vitreous, retina, choroid, sclera, lens, cornea, hyaloid, iris, ciliary body, Schlemm's canal | given fluid inlet on the ciliary body, given pressure at the trabecular meshwork, sclera and cornea; given drug flux or drug concentration at the different outer surfaces, according to the specific considered delivery route | porous jump across membranes |
[14] juxtascleral | 2012 | 2D human | choroid, sclera | impermeable conditions at sclera/cornea and sclera/optic nerve interfaces, blood inlet at the optic nerve/choroid interface; porous jump at the internal surface of the choroid | no slip condition for velocity, continuous drug conc and flux |
[17] IV injection, episcleral, systemic | 2014 | 3D human modified from [13] | vitreous, retina, choroid, sclera | null fluid flux at the lens, fluid pressure equal to episcleral pressure at sclera, IOP pressure at hyaloid; prescribed drug loss at the ASE and at sclera surface, null drug flux at hyris/lens | |
[19] episcleral | 2014 | 3D human | vitreous, retina, choroid, sclera | no slip conditions for flow at the external boundaries, except for inlet/outlet arteries and veins | porous jump across membranes with partition coefficient |
[12] IV injection, episcleral, systemic (oral) | 2014 | 3D human modified from [13] | vitreous, retina, choroid, sclera | fluid pressure equal to IOP at hyaloid membrane and to episcleral veins pressure at sclera; imposed drug outward flux at hyaloid, drug filtration at sclera, no permeation of aqueous humor and drug through the lens | |
[20] episcleral | 2016 | 1D human | vitreous, retina (tissue + blood), choroid, sclera | no flux from the vitreous; prescribed drug concentration at the sclera boundary | porous jump across membranes with partition coefficient |
[22] | 2016 | 3D human | vitreous, retina | prescribed fluid pressure at the boundaries and zero normal component; zero flux at the vitreous boundary, jump conditions at the retinal boundary |
fluid pressure continuity; porous jump across membranes |