Fig 1.
Comparison of the HV vs. conventional guillotine vitreous cutter.
(A) 23-gauge hypersonic vitrector needle (center) compared with 25-gauge (right) and 23-gauge (left) of guillotine needle. (B) High-magnification image of the tip and port of the hypersonic vitrector.
Fig 2.
Open-sky and closed Pars Plana Vitrectomy (PPV) procedures in porcine cadaver eyes.
(A) Removal of the cornea, crystalline lens and iris “en bloc” from the eye. (B) Porcine cadaver eye ready for the open-sky vitrectomy, showing the core vitreous and the posterior pole without any retinal detachment. (C) Closed PPV with the hypersonic vitrector through the 23-gauge trocar system.
Fig 3.
Hematoxylin-eosin stained horizontal retinal sections from porcine cadaveric eyes after pars plana vitrectomy procedures.
(A) Section from a control eye without any procedure. (B and C) Retinal sections from eyes that underwent pars plana vitrectomy with a guillotine vitrector at 3000 or 5000 cuts per minute. ILM separation (B) and minimal disintegration at inner retinal layers (B, C). (D, E, and F) Retinal sections from eyes that underwent pars plana vitrectomy with a hypersonic vitrector at settings of 30% (D), 40% (E), and 50% (F) US power showing vacuolization, fragmentation of the nerve fiber and ganglion cell layers and inner limiting membrane separation without any disruption. (A, B D and E) Sections from a open-sky vitrectomy procedures. (C and F) Sections from a closed vitrectomy procedure.
Fig 4.
Hematoxylin-eosin stained sections through the optic nerve head from porcine cadaveric eyes after PPV.
(A and B), Sections from eyes that underwent pars plana vitrectomy using the guillotine cutter at 3000 cuts per minute (A) or 5000 cuts per minute (B). (C, D, E and F), Sections from eyes that underwent pars plana vitrectomy using the hypersonic vitrector set at 20% (C), 30% (D), 40% (E), and 50% (F) ultrasound power. (A) and (F) show a subhyaloid haemorrhage and retinal detachment. E shows presumed artifactual detachment. (A, C, D and E) Sections from a open-sky vitrectomy procedures. (B and F) Sections from a closed vitrectomy procedures.
Fig 5.
Macroscopic figures showing the effects of touching a guillotine.
(A) or hypersonic (B) vitrector to the posterior capsule of a cadaveric porcine crystalline lens. Microscopic analysis showing disruption of the posterior capsule of the lenses is extensive with the guillotine vitrector (C) and focal with the hypersonic vitrector (D). Artifactual loss of tissue is also seen in (D).
Fig 6.
Hematoxylin-eosin stained histological sections of human retina after pars plana vitrectomy.
All sections (A-C and F) show fragmentation and separation of the inner limiting membrane. (A and B) vitrectomy with a guillotine vitrector at 3000–5000 cuts per minute. (C) vitrectomy with a hypersonic vitrector at 40%–50% ultrasound power. (D-E) Differential interference contrast microscopy to enhance the contrast of ILM. (E) magnified image showing ILM fragmentation. (F) vitrectomy with a hypersonic vitrector at 40%–50% ultrasound power. Disciform macular degeneration.
Fig 7.
Transmission electron microscopy of human vitreous samples after pars plana vitrectomy with the hypersonic vitrector.
(A and B) Vitrectomy at 20% ultrasound power showing fragmentation of the human vitreous collagen fibrils. The levels of collagen fibril fragmentation increased with increasing ultrasound power. (C and D) at 30% ultrasound power. (E and F) at 50% ultrasound power.
Fig 8.
Transmission electron microscopy of human vitreous samples after pars plana vitrectomy with the guillotine vitrector.
(A, B, C) GV at 3000 cuts per minute. (D, E, F) GV at 5000 cuts per minute. The figures show less fragmentation of the collagen fibrils compared to those obtained from the hypersonic vitrector shown in Fig 7.
Fig 9.
Non-recovery anaesthesia live animal experiments.
(A) Shows the hypersonic vitrector over the macula and (B) Shows the hypersonic vitrector (HV) over ONH. Guillotine and hypersonic cutters were operated 3–5 mm from the retina over the macular area and the optic nerve head (ONH) for 5 minutes each (nasal area served as control).
Fig 10.
Hematoxylin-eosin stained horizontal sections in non-recovery anaesthesia live animal experiments.
Hematoxylin-eosin stained horizontal sections through the optic nerve head and the areas nasal and temporal to the nerve head after pars plana vitrectomy using a hypersonic vitrector at 10%, 20%, 40%, or 50% ultrasound power. Vacuolization can be seen at all settings, as well as fragmentation of the nerve fibers and ganglion cell layers. The inner limiting membrane showed separation without disruption. (RE = right eye; ONH = optic nerve head; LE = left eye).