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Assistant-Independent OptiFlex System for Contact and Noncontact Wide-Angle Viewing in Vitreoretinal Surgery

Authors:
Ravi Keshavamurthy at Kaiser Permanente
Ravi Keshavamurthy
Kakarla Chalam at University of Florida
Kakarla Chalam
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The wide-angle viewing system during vitreoretinal surgery has lead to an increased success rate of complex procedures. Two types of wide-angle viewing systems are in use, contact and noncontact, each with its own advantages and disadvantages. In this article, we describe an optical system, OptiFlex, that is designed to combine the advantages of the contact and noncontact systems by enabling the surgeon to switch between them with ease and without skilled surgical assistance. Arch Ophthalmol. 2010;128(4):490-492
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SURGEON’SCORNER
NEW INSTRUMENT
Assistant-Independent OptiFlex System
for Contact and Noncontact Wide-Angle
Viewing in Vitreoretinal Surgery
Ravi K. Murthy, MD; Kakarla V. Chalam, MD, PhD
The wide-angle viewing system during vitreoretinal surgery has lead to an increased suc-
cess rate of complex procedures. Two types of wide-angle viewing systems are in use,
contact and noncontact, each with its own advantages and disadvantages. In this ar-
ticle, we describe an optical system, OptiFlex, that is designed to combine the advan-
tages of the contact and noncontact systems by enabling the surgeon to switch between them with
ease and without skilled surgical assistance. Arch Ophthalmol. 2010;128(4):490-492
Viewing in vitreoretinal surgery has
evolved from conventional handheld
planoconcave lenses to the present
wide-angle viewing systems.1,2 The
wide-angle system allows a detailed
panoramic intraoperative view of the
retina through a small pupil, intraocular
lens, or keratoprosthesis. This techno-
logical advance has revolutionized vit-
reoretinal surgery, making it more effi-
cient and improving the success rate of
complicated operations.3
Two types of wide-angle systems are
currently in use: noncontact and con-
tact.1The advantages of a noncontact
viewing system are that a skilled surgical
assistant is not required; there is no
intraoperative corneal trauma; and it
provides a good view during air-fluid
exchange and in patients with steep cor-
neas. However, the image resolution and
stereopsis are superior with the contact
system, as it eliminates naturally occur-
ring corneal aberrations and limits the
number of reflecting surfaces.4The limi-
tations with the contact system include
poor views in patients with corneal
trauma and the need for a skilled surgical
assistant.1
A viewing system that combines the
advantages of both the contact and non-
contact systems gives the surgeon great
flexibility while operating on complex
vitreoretinal cases. OptiFlex (Volk, Men-
tor, Ohio), a new device, combines the
benefits of the 2 systems by allowing sur-
geons to switch easily between them,
eliminating the need for a skilled surgical
assistant.
OptiFlex, an electromechanical sys-
tem, guided through an operator-feed-
back system, senses the tension in the as-
sistant unit, makes microadjustments in
the electronic output, and optimizes lens
positioning and focus during vitreoreti-
nal surgery. It consists of a lens-position-
ing unit, which is attached to the micro-
scope using an adapter plate (Figure 1A)
and a reinverting operating lens system
(Figure 1B). The lens-positioning unit
acts through a swinging and pivoting ac-
tion and easily moves in and out of the
operating field. The ophthalmic surgical
lenses (both contact and noncontact) are
mounted onto the flexible arm of the lens-
positioning unit, and the movement of
the lens in the z-axis is controlled by a
power-operated foot switch to achieve
fine focus intraoperatively. When tension
is applied with assistance of the power
source, the flexible arm locks into posi-
tion and stabilizes the lens over the cor-
nea. The surgeon controls the initiation as
well as termination of tension with assis-
tance of the foot pedal and adjusts the po-
sition and orientation of the lens without
the need of a surgical assistant.
The reinverting operating lens is
positioned between the zoom system
Author Affiliations: Department of Ophthalmology, University of Florida College
of Medicine, Jacksonville.
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©2010 American Medical Association. All rights reserved.
at University of Florida, on April 12, 2010 www.archophthalmol.comDownloaded from
and the beam splitter of the conventional operating
microscope and reinverts the image, creating a true,
erect, stereoscopic fundus to facilitate critical surgical
maneuvers. The reinverting operating lens system is
automated and controlled by the foot switch, eliminat-
ing the need for an assistant to move the prism lever
manually.
The surgical lenses are made of high-index glass and
are of both the contact and noncontact systems by de-
sign (Figure 2). The lenses are sterilized with standard
autoclave protocol. The surgeon switches from a con-
tact to a noncontact system by attaching the appropriate
lens to the lens-positioning unit (Figure 3). The intra-
operative field of view through the wide-angle lens is ap-
proximately 120°.
COMMENT
The wide-angle system has resolved many of the view-
ing challenges faced in vitreoretinal surgery and pro-
vides a panoramic view of the fundus with great
clarity.1The noncontact system binocular indirect
ophthalmomicroscope incorporates the system of indi-
rect ophthalmoscopy in the operating microscope,
while the contact system uses a miniaturized aspheric
contact panfundoscopic lens to provide wide-angle
observation of the fundus during vitreous surgery.5
Both the contact and the noncontact systems require
stereoscopic inversion of the images, which is
achieved by a prism set cased in an airtight, light-
weight container incorporated or positioned into the
microscope.1
The advantage of a noncontact wide-angle viewing sys-
tem like binocular indirect ophthalmomicroscope is that
a skilled surgical assistant is not required to hold the view-
ing contact lens. However, the image resolution and ste-
reopsis are inferior to the contact system in evaluating
the peripheral retina owing to spherical aberrations, im-
age distortion, and edge blur.1,4 The contact system elimi-
nates naturally occurring corneal aberrations and limits
the number of reflecting surfaces. The OptiFlex is de-
signed to combine the advantages of both the contact and
noncontact systems. The lens-positioning unit is de-
signed to accommodate lenses of either system. It pro-
vides a high-quality image using the contact system with-
out the help of a skilled surgical assistant. In addition,
the viewing system can be switched to a noncontact mode
in cases in which corneal distortion occurs with the con-
tact lens.
We used the system in more than 100 cases of com-
plex vitreoretinal surgery. The OptiFlex wide-angle
system anchors and stabilizes the surgical lens on the
B
A
Figure 1. OptiFlex system for contact and noncontact wide-angle viewing in
vitreoretinal surgery. A, The lens-positioning unit is attached to the operating
microscope through an adapter. B, The reinverting operating lens system is
positioned in between the eye piece and the beam splitter of the operating
microscope.
Figure 2. Wide angle (both contact and noncontact systems) lenses are fixed
to the lens-positioning unit during vitreoretinal surgery.
Figure 3. Surgeon using the OptiFlex system (contact lens mode) during
vitreoretinal surgery.
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491
©2010 American Medical Association. All rights reserved.
at University of Florida, on April 12, 2010 www.archophthalmol.comDownloaded from
patient’s corneal surface and obviates the need for an
assistant during vitreoretinal operations. The newer
design of the contact wide-angle system (with a 130°
view) is compact and does not interfere with vitrec-
tomy instruments. The fundus image clarity and field
of view throughout the surgical procedures was excel-
lent. The accessibility of having the desired field of
view for vitrectomy shortened the surgical time. No
compromise of the corneal surface was noted. The
OptiFlex was equally adept in assisting, whether or
not the adjunct was the contact or noncontact lens.
Submitted for Publication: August 19, 2009; final revi-
sion received October 12, 2009; accepted October 19,
2009.
Correspondence: Kakarla V. Chalam, MD, PhD,
Department of Ophthalmology, 580 W Eighth St,
Tower 2, 3rd Floor, Jacksonville, FL 32209 (kchalam
@jax.ufl.edu).
Financial Disclosure: None reported.
REFERENCES
1. DeGregorio PG, Hammer ME, Grizzard SE. Wide-angle viewing systems in vitreo-
retinal surgeries. In: Peyman GA, Meffert SA, Chou F, Conway MD, eds. Vitreo-
retinal surgical techniques. 2nd ed. London, England: Martin Dunitz; 2007:99-
106.
2. Shah VA, Chalam KV. Autoclavable wide-angle contact lens for vitreous surgery.
Am J Ophthalmol. 2004;137(2):359-360.
3. Lesnoni G, Billi B, Rossi T, Stirpe M. The use of panoramic viewing system in re-
laxing retinotomy and retinectomy. Retina. 1997;17(3):186-190.
4. Chalam KV, Shah VA. Optics of wide-angle panoramic viewing system–assisted
vitreous surgery. Surv Ophthalmol. 2004;49(4):437-445.
5. Landers MB, Peyman GA, Wessels IF, Whalen P, Morales V. A new, non-contact
wide field viewing system for vitreous surgery. Am J Ophthalmol. 2003;136(1):
199-201.
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... Different generations of contact lenses have been successively designed to improve the quality of the peripheral fundus view during examination and surgery while minimizing image distortion. [1][2][3][4][5] However, currently available lens systems are bulky, adding discomfort to the procedure and requiring superior skills, as the pupil, the lens, and the operator have to be coaxial to obtain a good-quality image. In this report, we describe the optical design of a novel miniaturized lightweight contact lens system for panretinal photocoagulation (PRP), and compare it with the SuperQuad 160 lens system (Volk Optical, Inc., Mentor, OH, USA). ...
... Various contact and noncontact lens systems are available to enhance the visualization of the retina for these purposes. [1][2][3][4][5][6] The previous generation of wide-field contact lens systems (SuperQuad 160) uses a wider aperture to expand the field of view. This leads to an inherent difficulty in using the lens due to its bulky design. ...
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The purpose of the article is to describe the optics of the contact wide-angle lens system with stereo-reinverter for vitreous surgery. A panoramic viewing system is made up of two components; an indirect ophthalmoscopy lens system for fundus image viewing, which is placed on the patient's cornea as a contact lens, and a separate removable prism system for reinversion of the image mounted on the microscope above the zooming system. The system provides a 104 degrees field of view in a phakic emmetropic eye with minification, which can be magnified by the operating microscope. It permits a binocular stereoptic view even through a small pupil (3 mm) or larger. In an air-filled phakic eye, field of view increases to approximately 130 degrees. The obtained image of the patient's fundus is reinverted to form true, erect, stereoscopic image by the reinversion system. In conclusion, this system permits wide-angle panoramic view of the surgical field. The contact lens neutralizes the optical irregularities of the corneal surface and allows improved visualization in eyes with irregular astigmatism induced by corneal scars. Excellent visualization is achieved in complex clinical situations such as miotic pupils, lenticular opacities, and in air-filled phakic eyes.
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Wide-angle viewing systems in vitreoretinal surgeries
  • 99-106
  • Pg Degregorio
  • Me Hammer
  • Se Grizzard
  • Ga Peyman
  • Sa Meffert
  • F Chou
  • Md Conway
DeGregorio PG, Hammer ME, Grizzard SE. Wide-angle viewing systems in vitreoretinal surgeries. In: Peyman GA, Meffert SA, Chou F, Conway MD, eds. Vitreoretinal surgical techniques. 2nd ed. London, England: Martin Dunitz; 2007:99- 106.