Vitreoschisis in macular diseases

Abstract

Objectives: Vitreoschisis is a possible pathogenic mechanism in macular diseases. Thus, the vitreoretinal interface was evaluated in monkey eyes and patients with various macular diseases in search of vitreoschisis. It is hypothesised that vitreoschisis is present in macular holes (MH) and macular pucker (MP), but not in other maculopathies.

Methods: Histopathology was studied in 14 monkey eyes and a vitrectomy specimen of a patient with macular pucker. Optical coherence tomography/scanning laser ophthalmoscopy (OCT/SLO) was performed in 239 eyes: 45 MH, 45 MP, 51 dry age-related macular degeneration (AMD), 53 non-proliferative diabetic retinopathy (NPDR) and 45 controls.

Results: Immunohistochemistry demonstrated lamellae in the posterior vitreous cortex of 12/14 (86%) monkey eyes. With OCT/SLO, vitreoschisis was detected in 24/45 (53%) MH and 19/45 (42%) MP eyes, but in only 7/53 (13%) NPDR, 3/51 (6%) AMD and 3/45 (7%) control eyes (p<0.001 for all comparisons). Rejoining of the inner and outer walls of the split posterior vitreous cortex was visible in 16/45 (36%) MH eyes and 15/45 (33%) MP eyes. Histopathology of the MP specimen confirmed a split with rejoining in the posterior vitreous cortex.

Conclusions: Vitreoschisis was detected in half of eyes with MH and MP, but much less frequently in controls, AMD and NPDR patients. These findings suggest that anomalous PVD with vitreoschisis may be pathogenic in MH and MP.

Figure 1

Immunofluorescence of the monkey vitreoretinal interface. The lamellae of the mammalian posterior vitreous cortex are seen anterior to (above) the intensely stained internal limiting lamina. (effective magnification ~400×).

Figure 2

Vitreoschisis in macular hole. Longitudinal optical coherence tomography and scanning laser ophthalmoscopy (lower left hand corner) imaging of the vitreoretinal interface in an eye with a stage III macular hole demonstrates the inner (white arrow) and outer (black arrow) walls of the vitreoschisis that is readily apparent in this case.

Figure 3

Vitreoschisis in macular pucker. Longitudinal optical coherence tomography and scanning laser ophthalmoscopy (lower right hand corner) imaging of the vitreoretinal interface in an eye with a grade II macular pucker demonstrates the two walls (inner wall=arrow; outer wall=asterisk) of vitreoschisis forming a ‘lambda’ sign where they rejoin.

Figure 4

Optical coherence tomography/scanning laser ophthalmoscopy imaging of vitreoschisis in macular pucker. The left-hand side of the image demonstrates a split in the posterior vitreous cortex, or ‘vitreoschisis.’ The specimen was removed surgically (JS) and studied by histopathology (see figure 5).

Figure 5

Histopathology of vitreoschisis in macular pucker. (A) Periodic acid–Schiff staining showing the split (purple arrow) in the vitreous membrane removed at surgery. Embedded in this tissue are two hyalocytes (black arrows), consistent with the concept that this tissue is the posterior vitreous cortex (courtesy of N Rao, MD; magnification=225×). (B) Surgical specimen (same subject as that in (A)) showing positive staining with Alcian Blue, confirming its origin as the posterior vitreous cortex (courtesy of N Rao, MD; magnification=300×).