When Office-based Vitrectomy Makes Sense

The authors share their experience performing vitreoretinal surgery in the office.

LILIYA SHEVCHENKO, DO • SCOTT J. WESTHOUSE, DO • THOMAS M. AABERG, JR., MD

If we look at the evolution of vitreoretinal surgery within the context of medical history, the pace of advancement has been remarkable. Small-gauge vitrectomy with transconjunctival ports coincided with other medical-economic factors, such as a push to contain costs, decrease waste, and increase efficiency. These factors have prompted a discussion and exploration of office-based vitreoretinal surgery.

A DECADE OF DEVELOPMENTS

The last decade has produced a number of publications proposing or investigating the feasibility of office-based vitrectomy surgery. In 2000, Trese et al reported on nine patients who underwent autologous plasmin enzyme-assisted macular hole surgery.¹ Although the authors performed the surgeries in the operating room, they explained how enzymatic vitrectomy could shift procedures from the operating room to the office.

They claimed that by simplifying each step of macular hole surgery — limiting the suction of the posterior hyaloid, avoiding ILM manipulation, and incompletely filling with gas — the surgery could potentially be performed in the physician’s procedure room.

In 2002, Hilton et al reported on the indications for office-based two-port vitrectomy in a large, multicenter case series.² Although the majority of described cases were diagnostic, several cases had therapeutic indications, such as lens fragment removal, retinal detachment repair, and treatment of ghost cell glaucoma.

The authors’ reported complication rate was 6.6%, with 0.4% of these cases considered severe complications (rhegmatogenous retinal detachment), as defined by Stein et al.³ In 2011, Koch and Koss reported on a large case series of portable single-port vitrectomies performed on 4,509 eyes, with 62.9% (2,836 eyes) carried out in the office setting.⁴ In their report, the authors did not differentiate indications and complication rates between hospital and office sites.

In 2013, Doyle and Pitcher reviewed several vitrectomy machines and defined a portable vitrectomy unit as a machine that is easy to transport and compatible with office-based vitrectomy and that can run on battery power.⁵

A PROMISING TECHNOLOGY

The prospect of office-based vitrectomy resulted from the evolution of less invasive, more efficient, safer surgical equipment and techniques. However, the vitrectomy units, microscopes, viewing systems, and expensive surgical packs found in today’s operating rooms create financial hurdles prohibitive to office-based economics.

If office-based vitrectomy surgery is to become one more arrow in our surgical quiver, we must create more economical equipment suitable for the procedure room. As we explored the possibility of office-based surgery, we partnered with Synergetics USA, Inc. (O’Fallon, MO) to create a powerful, portable, yet economic vitrectomy machine.

Evolution of Office-based Vitrectomy

Such a unit has appealed to a number of vitreoretinal surgeons over the years. In 1979, Kingham et al found a portable vitrectomy unit (VISC-X) useful in the rural setting of Guatemala for cases that otherwise would have been inoperable or very difficult to manage.⁶

In 1979, Parel and deGuillebon challenged the existing concept of large, bulky, and complex vitrectomy consoles by introducing a handheld solitary unit, the VITAC (VItreous Tissue Aspiration Cutter).⁷ The authors envisioned a vitrectomy unit that would be portable, simple to operate, and easy to set up.

In 1996, Singh et al reported a series of 19 patients who underwent successful office-based diagnostic 23-gauge sutureless vitrectomy for endophthalmitis and vitritis.⁸

All of these authors stressed the points of cost-effectiveness, timeliness of diagnosis, and treatment of potentially blinding conditions. In this article, we discuss our experience with in-office vitrectomy surgery (Table 1). We aim to highlight the equipment necessary to create our office-based vitrectomy procedure room and to provide case examples and a summary of our office-based vitrectomy results. Our intent is to promote discussion regarding the potential benefits and risks of vitrectomy surgery in an office setting.

Table 1. Protocol for Office-based Vitrectomy

1)	Oral 10 mg diazepam x 1.
2)	Retrobulbar block in the exam lane.
3)	Setup of the vitrectomy unit, instrument tray, and microscope in the procedure room.
4)	Transfer of the patient to the procedure room.
5)	Betadine solution 10% preparation of the globe, lashes, and periorbital area.
6)	Sterile gown, surgical gloves, and surgical field draping.
7)	Application of an eyelid speculum.
8)	Insertion of ports and undertaking of pars plana vitrectomy and supplementary procedures.
9)	Examination of the fundus periphery, either under wide viewing system or binocular indirect ophthalmoscope, and treatment of any peripheral retinal pathology.
10)	Application of antibiotic ointment.
11)	Patching and shielding.
12)	Examination of patient on first postoperative day.

PROCEDURE ROOM AND EQUIPMENT

The Room

When designing or selecting your procedure room, the dimensions are critical. The procedure room must be able to hold a patient bed, microscope, vitrectomy unit, Mayo stand, cryogenic unit, laser, and personnel.

The room in which we performed our case examples is 12 ft by 16 ft. Portable racks and fixed cupboards store our surgical supplies, including surgical gloves, drapes, gowns, surgical instruments, disposable instruments, and medications.

As with the traditional operating room, all of the equipment is readily available. In fact, our procedure room varies little from a fully certified surgical suite. The differences include a lack of pressurized gases, positive pressurized filtered air, and anesthesia equipment.

The Vitrectomy Unit

Our office procedure room is equipped with a VersaVit (Synergetics) portable vitrectomy unit, which was introduced in October 2011 (Figure) and received 510(k) clearance from the FDA in the summer of 2012.⁹

Figure. Schematic (top) and corresponding photo (bottom) of portable vitrectomy unit: 1) vitrectomy port; 2) illumination ports; 3) cassette chamber; 4) fluid-air exchange port; 5) cassette ejection button; and 6) power button.

This unit is capable of 20-, 23-, 25-, and 27-gauge three-port vitrectomy. Its portability is ensured by utilization of novel technology. For example, the low-pressure vitrector drive system requires less compressed air and can achieve 2,500 cuts per minute (CPM). The newest updated version will achieve 6,000 CPM.

Compressed nitrogen, compressed air, or individual CO₂ cartridges power the pneumatic drive. The unit is powered by either 120-V alternating current or by the built-in rechargeable battery. The battery can run the system for approximately 60 minutes.

The aspiration system utilizes a diaphragm (Venturi-like) pump. A multifunctional foot pedal provides linear control of aspiration (ranging from 0 to 500 mm Hg). The cassette consists of two 50-cc collection tubes.

The tubes are individually backlit green or red to provide a visual clue as to the status of each tube. Green indicates the vial is pulling proper vacuum and is ready for use, while red means the vial is full, missing, or unable to pull vacuum.

Pressurized air from the console driven into a basic salt solution (BSS) bottle achieve forced infusion and adjustable IOP. The maximum IOP is 120 mm Hg. The machine has two independent LED outputs rated at 25,000 hours. The LED illumination is filtered at 435 nm.

Microscope and Viewing System

We use a Leica Microsystems M841 (Wetzlar, Germany) surgical microscope. This microscope has a fully functional foot pedal capable of controlling magnification, focus, and spatial position.

The microscope also has an adjustable light system, assistant side scope, and camera with video recording capabilities. Wide-angle noncontact viewing can be achieved with the Merlin (Volk Optical, Mentor, OH) viewing system. A flat disposable contact lens is used when indicated for enhanced visualization of the macula.

EXAMPLE CASE REPORTS

Case 1

A 40-year-old man presented with nonclearing vitreous hemorrhage due to trauma and open globe, which was primarily closed at an outside hospital. His VA was 20/200. In the office procedure room, he underwent conventional three-port pars plana vitrectomy with a 2,500 CPM rate. Anesthesia consisted of a retrobulbar block and 5 mg of diazepam.

The patient was found to have a retinal tear, which we treated with binocular indirect laser photocoagulation attached to the office laser unit (Iridex, Mountain View, CA). Complete fluid-air exchange was performed at the end of the case.

The duration of the surgery was 54 minutes. The patient’s VA at three months was 20/25. The patient was stable four months following office-based vitrectomy and returned to his primary ophthalmologist.

Case 2

A 50-year-old, insulin-dependent man developed a postoperative vitreous hemorrhage following pars plana vitrectomy, membrane peeling, and endolaser for a tractional retinal detachment. The initial procedure was performed in a conventional operating room setting.

One month after surgery, the patient’s vision remained hand motion, and the vitreous blood showed no signs of clearance. He consented to office-based three-port vitrectomy. He received 10 mg of diazepam and a retrobulbar block. Twenty-five–gauge three-port pars plana vitrectomy (2,500 CPM) successfully cleared the vitreous hemorrhage without complications.

The surgery duration was 30 minutes. Three months postoperatively, the patient’s VA was 20/70. He was followed for 12 months, and his VA deteriorated to 20/200 due to cataract formation.

Case 3

An uninsured 61-year-old woman presented with 20/80 VA due to a macular pucker and epimacular membrane formation. In the office procedure room, under a retrobulbar block and 10 mg of diazepam, she underwent complete vitrectomy and en bloc epimacular membrane and ILM peeling using indocyanine green dye enhancement.

A flat macular lens and Pinnacle 360 ILM forceps (Synergetics) were used for ILM stripping. The surgery duration was 60 minutes. The patient’s VA at three months following surgery was 20/50. She was followed for 13 months, and her best VA was 20/30.

Results

We accomplished the surgical goals in all of these office-based procedure room cases. All patients experienced improvement in VA. No technical problems occurred with the microscope, viewing system, laser, or vitrectomy unit. Ancillary instrumentation, such as binocular indirect laser, intraocular forceps, flat contact lens, and soft-tip intraocular cannulas, was required in some cases.

The average surgical time was 48 minutes (range 30-60 minutes). All cases received local anesthesia including 5-10 mg of diazepam prior to retrobulbar block. Employed ophthalmic technicians acted as the surgical technician and circulator. The average follow-up period was 9.6 months (range four to 13 months). No instrument- or procedure-related complications arose.

COMMENTS

The indications for office-based vitreoretinal surgery are not well defined, and they largely depend upon the surgeon’s comfort level, patient selection, conduciveness of the office space, availability of trained personnel, and cost-benefit analysis. The majority of reported office-based vitrectomies have been performed as one- or two-port procedures. Our cases were all three-port vitrectomy.

Some authors have argued that one- or two-port vitrectomy is indicated in the office setting, because fewer incisions theoretically translates into shorter procedure duration, lower associated costs, and fewer complications.^4,10,11

While this may be true in some cases, we found that using a three-port vitrectomy unit in the office-based procedure room provided the surgeon an opportunity to expand the indications for vitreoretinal surgery performed in the office setting, while maintaining safety. In addition, we found the cutting abilities, illumination, and trocar system of the portable unit comparable to those of other nonportable vitrectomy systems.

Four major functions of vitrectomy procedures — infusion, cutting, extrusion, and fluid-gas exchange — were tested and appeared to perform well in the office setting. The operating microscope, wide angle viewing system, and disposable contact lens allowed the same visualization we have become accustomed to in the operating room. For surgeons, the familiarity of the equipment will be reassuring in the nontraditional setting of the office procedure room.

A Cost-benefit Analysis

What are the benefits of office-based vitrectomy? The main benefits are efficiency, expediency, and cost-effectiveness. Particularly for those surgeons without immediate access to an ambulatory surgical center, having procedure room vitrectomy capability allows for prompt intervention in urgent cases, such as endophthalmitis.

Office-based vitrectomy also has a role to play in routine cases, such as postoperative diabetic vitreous hemorrhages. Being able to move a patient from the exam room to the procedure room to clear a postoperative vitreous hemorrhage can circumvent both the patient’s and surgeon’s emotional hurdles of returning to the operating room.

From a resource management viewpoint, we use trained ophthalmic technicians as circulators and surgical technicians, and we maximize the use of our own facilities. These staff members are already “on the clock,” and our office rent is part of our existing overhead expense.

For the uninsured patient, we can control costs and patient charges, which is particularly important for patients with macular holes and symptomatic macular puckers who may otherwise not be able to afford vision-restoring surgery.

Finally, for third-party payers, office-based vitrectomy represents possible cost containment. Although it in no way reduces the complexity or duration of cases, it does reduce facility and anesthesia costs.

Proceed With Caution

What are some of the cautionary issues that can arise with office-based vitrectomy surgery? The principal concerns include patient safety, case selection, and financial feasibility.

Regarding patient safety, the risk of endophthalmitis and health problems must be evaluated. We prep and sterile drape every patient, and we fully gown and glove ourselves to mitigate the risk of endophthalmitis.

Because we do not have an anesthesiologist in the room, the surgeon must be prepared to provide first aid in cases of adverse cardiovascular events. Supplemental oxygen, a pulse oximeter, and a sphygmomanometer should be available.

Of course, the patient must be able to remain still under minimal sedation for the duration of surgery, so case selection is important and should be limited to medically, mentally, and emotionally stable patients. Because the complexity of a case frequently dictates its duration, the surgeon must be self-critical when taking into account his or her comfort and skill level.

Office Economics

The surgeon must also understand the economics of the office-based vitreoretinal procedure. One thing to consider is that unlike the global fee (which is the sum of the surgeon’s fee and the facility fee), the surgeon’s fee remains the same regardless of where the surgery is performed.

Among the intangible cost benefits for the surgeon and patient of in-office vitreoretinal procedures are timeliness in urgent cases and the elimination of travel time to and dependence on availability of the ambulatory surgical center.

Facility fees are paid only to accredited surgical centers. However, the physician can negotiate with payers (particularly private payers) to retain part of the facility fee. This fee must cover durable capital expenses and fixed costs (paid in advance), as well as disposable costs.

Durable capital equipment includes, but is not limited to, the vitrectomy unit, surgical microscope, wide-angle viewing system, autoclave, laser, cryogenic unit, surgical bed, Mayo stand, and surgical tray with instruments (Tables 2 and 3, pages 25 and 26). Many of the listed items are already present in the retinal physician’s office, so no cost is associated with acquiring them. Disposable sterile procedure room supplies may vary depending on practice pattern (Table 4, page 27). The costs associated with disposable equipment are relatively uniform and depend on the portable vitrectomy unit used (Table 5).

Table 2. Procedure Room Durable Capital Equipment Costs

Capital Equipment
Vitrectomy unit (VersaVit, Synergetics)	$30,000
Surgical microscope (Leica)	$55,000
Viewing system (Merlin, Volk)	$10,000
Autoclave	NC
Laser	NC
Cryogenic unit	NC
Surgical bed	NC
Mayo stand	$424.38
Surgical tray with instruments	$2,214.67
Total Initial Capital Equipment Cost	$97,639.05

Table 3. Procedure Room Durable Equipment Costs

Surgical Instrument Tray
Scleral plug forceps	$233.00
Troutman needle holder	$333.60
Castroviejo needle holder	$205.60
Westcott scissors (Fairfield, CT)	$244.80
Speculum	$29.60
Alfonso speculum	$60.00
Stevens tenotomy curved scissors	$103.20
Retina hook	$66.40
Suture forceps	$321.60
Fixation forceps	$214.60
Irrigation cannula (autoclavable)	$20.80
Blunt 18-gauge cannula (disposable)	$0.23
Scleral depressor	$114.40
Lancaster speculum	$89.60
Mosquito hemostat	$21.24
Instrument tray	$156.00
Total Surgical Tray Cost	$2,214.67

Table 4. Procedure Room Sterile Supplies: Cost per Case

Prep of surgical gloves	$0.98
Prep of sterile scrubs	$0.73
Gloves	$1.40
Sterile 4” x 4” gauze (pkg of 10)	$0.62
Iodine cup (autoclavable)	$15.00
Povidone-iodine solution	$1.20
Eye pad	$0.16
Eye shield	$1.98
U drape	$11.26
Sterile drape 18” x 26”	$0.25
Back table sterile drape	$2.39
Mayo stand cover	$2.13
Incision drape	$13.50
Sterile bulb	$0.89
Surgical mask	$0.44
Bouffant cap	$0.16
Sterile strip 1/2” x 4”	$1.17
GonioVisc (hypromellose, Sigma, Monticello, ID)	$3.56
BSS 15 mL	$3.56
Bupivacaine 0.75	$4.17
Lidocaine HCl 2%	$3.54
Gentamicin 2 mL	$4.17
Intravitreal triamcinolone acetonide	$12.50
Sterilization pouch 7.5” x 13”	$0.12
Sterilization pouch 3.5” x 9”	$0.06
Sterilization wrap	$0.92
Total Cost	$86.86

Table 5. Procedure Room Disposable Equipment Costs

Virectomy Disposables For Macular Cases
Soft-tip cannula, 25-gauge	$22.00
Flat lens	$30.00
Fine-tip Eckardt forceps, disposable	$100.00
Balanced saline solution	$10.00
Efficiency pack (cutter and cassette)	$130.00
Adjustable gas-pressurized tubing	$31.50
Aspiration line with three-way stopcock	$10.00
25-gauge trocar cannulas	$71.00
25-gauge midfield light pipe	$24.38
Total Cost/Case	$428.88

Indications for Office-based Vitrectomy

We consider the following to be reasonable indications for office-based vitreoretinal surgery:

• vitreous hemorrhage with or without retinal tear; macular pucker;

• macular hole;

• symptomatic vitreous opacities; endophthalmitis; vitreous biopsy;

• uncomplicated pseudophakic retinal detachment; uncomplicated diabetic vitreous hemorrhage; and

• limited retained lens material (particularly if primarily cortical lens material) following complicated cataract surgery.

Due to the limited number of patients we have treated in our office, our results should be considered investigational, and patients treated in such a setting must be counseled.

We did not encounter any machine-related complications. The risk-benefit profile appears to be favorable. The patients had uneventful surgeries with good visual and anatomic outcomes. The cost-benefit profile, which appears favorable, must be addressed on a larger scale.

CONCLUSION

Industry is working with surgeons to produce cost-effective, safe, reliable equipment. Further study of patient safety, equipment utilization costs, efficacy, and expanded use in nontraditional surgical settings (the office or remote areas) is warranted.

In our limited experience, we believe that office procedure room–based vitrectomy will bolster the capabilities of vitreoretinal surgeons in the United States and overseas. RP

REFERENCES