25-gauge System Research Articles

Outcomes of 77 Consecutive Cases of 23-Gauge Transconjunctival Vitrectomy Surgery for Posterior Segment Disease

To describe the initial experience, effectiveness, and safety profile of 23-gauge instrumentation for a variety of vitreoretinal conditions. Single-center, retrospective, noncomparative, consecutive interventional case series. Seventy-seven eyes of consecutive patients who underwent 23-gauge transconjunctival vitrectomy surgery by a single surgeon at the Manhattan Eye, Ear, and Throat Hospital from October 2004 through October 2005. All patients underwent 3-port 23-gauge vitrectomy using Dutch Ophthalmic Research Corporation instrumentation and an Alcon Accuris Vitrector. Postoperative visual acuity at months 1 and 3, intraoperative and postoperative complications, and operative time. Mean acuity improved from 20/190 at baseline to 20/108 (P<0.0001) and 20/74 (P<0.0001) at months 1 and 3, respectively. By diagnosis, patients with epiretinal membrane (n = 20) improved from 20/124 to 20/93 (P = 0.0046), macular hole (n = 18) from 20/174 to 20/57 (P = 0.0007), rhegmatogenous retinal detachment (RD) (n = 14) from 20/248 to 20/51 (P = 0.0004), tractional RD (n = 12) from 20/175 to 20/62 (P = 0.0159), nonclearing vitreous hemorrhage (n = 12) from 20/1345 to 20/189 (P = 0.0004), vitreomacular traction (n = 4) from 20/145 to 20/124 (P = 0.7525), and retained lens fragments (n = 4) from 20/308 to 20/140 (P = 0.0972). One patient who underwent diagnostic vitrectomy had stable 20/50 acuity. Two patients had hypotony on postoperative day 1, 1 patient required a sutured sclerotomy intraoperatively, and no patients developed choroidal effusions. No intraoperative tears were noted. Surgical times collected on 17 patients during the final month of the study demonstrated a mean opening time (range) of 103 seconds (70-162), mean closing time of 75 seconds (17-470), and net operating time of 24.1 minutes (7.1-74.6). Twenty-three-gauge instrumentation is effective for a variety of vitreoretinal surgical indications. The safety profile compared favorably with published rates for 25-gauge systems.

Combined cataract surgery and 25-gauge sutureless vitrectomy for posterior lentiglobus

Combined cataract surgery and sutureless vitrectomy were performed in a 2-year-old boy with posterior lentiglobus. After an anterior capsulotomy was made, the lens nucleus was aspirated without hydrodissection to avoid posterior capsule rupture. The cortex was carefully aspirated because the central posterior capsule moved up and down during irrigation and aspiration. A pars plana vitrectomy was then performed with the sutureless 25-gauge system for an anterior vitrectomy with a posterior capsulotomy. A +27 diopter AcrySof intraocular lens (IOL) (Alcon) was implanted with the haptics in the bag and the optic behind the posterior capsulotomy with optic capture. Two months postoperatively, the IOL was centered and there were no complications. This surgical technique is easy and effective. It avoids complications, facilitates IOL implantation behind the posterior capsule, and improves the external appearance of the eye immediately postoperatively.

The Safety and Efficacy of Transconjunctival Sutureless 23-gauge Vitrectomy

PurposeTo evaluate the efficacy and safety of vitreoretinal surgery using a 23-gauge transconjunctival sutureless vitrectomy (TSV) system for various vitreoretinal diseases.MethodsA retrospective, consecutive, interventional case series was performed for 40 eyes of 40 patients. The patients underwent vitreoretinal procedures using the 23-gauge TSV system, including idiopathic epiretinal membrane (n=7), vitreous hemorrhage (n=11), diabetic macular edema (n=10), macular hole (n=5), vitreomacular traction syndrome (n=5), diabetic tractional retinal detachment (n=1), and rhegmatogenous retinal detachment (n=1). Best corrected visual acuity (BCVA), intraocular pressure (IOP), and intra- and post-operative complications were evaluated.ResultsIntraoperative suture placement was necessary in 3 eyes (7.5%). The median BCVA improved from 20/400 (LogMAR, 1.21±0.63) to 20/140 (LogMAR, 0.83±0.48) at 1 week (p=0.003), 20/100 (LogMAR, 0.85±0.65) at 1 month (p=0.002), 20/100 (LogMAR, 0.73±0.6) at 3 months (p=0.001). In 1 eye, IOP was 5 mmHg at 2 hours and 4 mmHg at 5 hours, but none of the eyes showed hypotony after 1 postoperative day. No serous postoperative complications were observed during a mean follow-up of 8.4±3.4 months (range 3-13 months)ConclusionsThe 23-gauge TSV system shows promise as an effective and safe technique for a variety of vitreoretinal procedures. It appears to be a less traumatic, more convenient alternative to 20-gauge vitrectomy in some indications.

Primary 25-gauge transconjunctival sutureless vitrectomy in pseudophakic retinal detachment.

There are few reports on 25-gauge transconjunctival sutureless vitrectomy (TSV) in cases of pseudophakic retinal detachment. We conducted this study to report the anatomic and functional outcomes of 25-gauge TSV in the treatment of primary pseudophakic retinal detachment (RD). Prospective, interventional case series. Fifteen eyes of 15 patients with RD after cataract surgery with phacoemulsification were evaluated. Primary pseudophakic RDs with macular detachment and proliferative vitreoretinopathy Stage B or less were included in the study. Pars plana vitrectomy with the 25-gauge TSV system, perfluorocarbon liquid injection followed by air exchange, endolaser photocoagulation and sulfur hexafluoride gas (20%) injection were applied to all eyes. Mean follow-up time was 9.2 months (range, six to 12 months). Retinal reattachment with a single operation was achieved in 93% of eyes and with additional surgery, the retina was reattached in 100% of eyes. Preoperative visual acuity was less than 20/200 in all eyes (range, hand motions to 20/400). Postoperative visual acuity was 20/40 or better in eight eyes (53%) and between 20/50 and 20/200 in seven eyes (47%). No severe hypotony was encountered and no sutures were required to close the scleral and conjunctival openings. Postoperative complications were macular pucker in one eye (7%) and cystoid macular edema in another eye (7%). Primary 25-gauge TSV system appears to be an effective and safe procedure in the treatment of uncomplicated pseudophakic RD.

Combined 25- and 23-Gauge Surgery: A New Sutureless Vitrectomy Technique

The 25- and 23-gauge sutureless vitrectomy techniques decrease the surgical trauma and improve patients' postoperative comfort. The disadvantages of the 25-gauge system include pliable instrument and slower gel removal. The 23-gauge system provides faster speed of vitrectomy and the instruments have stiffer shafts, but it requires a larger incision. To circumvent some of these limitations, a new sutureless transconjunctival vitrectomy technique that combines 23- and 25-gauge cannulas and instruments was studied. Fifty-three patients underwent vitreoretinal surgery using two 25-gauge ports for the infusion and light probe and one 23-gauge port for the vitreous cutter and various instruments. No intraoperative or postoperative complications were noted and no cases required conversion to another technique.

A Self-stabilizing Lens Ring for 25-Gauge Vitrectomy Surgery

To design an improved self-stabilizing lens ring for 25-gauge vitrectomy. Device report. A lens ring was designed to be fixated to the globe using 25-gauge transconjunctival cannulas. This ring consists of a single plastic component with multiple concavities at the ring margin to fit 25-gauge cannulas. The ring can accommodate conventional standard and panoramic vitrectomy lenses. A lens ring has been designed for 25-gauge vitrectomy and to hold conventional contact lenses. Stability of the lens ring is achieved without the need for sutures and instead is achieved by the three point fixation provided by the existing 25-gauge cannula system.

25-Gauge Transconjunctival Sutureless Pars Plana Vitrectomy

To evaluate the effectiveness, feasibility, and safety of the transconjunctival sutureless vitrectomy (TSV) system for a vriety of vitreoretinal diseases. In this retrospective study, the authors evaluated 71 eyes of 63 patients who underwent pars plana vitrectomy (PPV) with the 25-gauge TSV system. The indications for surgical intervention were diabetic vitreous hemorrhage (29 eyes), diabetic macular edema (14 eyes), macular epiretinal membrane (13 eyes), endophthalmitis (5 eyes), vitreous opacities secondary to Behcet's disease (4 eyes), vitreous hemorrhage secondary to branch retinal vein occlusion (4 eyes), and vitreous hemorrhage secondary to age-related macular degeneration (2 eyes). Epiretinal membrane and internal limiting membrane removal, endolaser photocoagulation, and air-fluid exchange were performed when required. Mean follow-up was 3.6 months (range 1-8 months). Mean overall visual acuity (VA) was counting fingers (range light perception to 0.4) preoperatively and 0.2 (range 0.1 to 0.8) postoperatively (p=0.000). Statistically significant VA improvement was observed in eyes with vitreous hemorrhage, diabetic macular edema, and macular epiretinal membrane. VA improved postoperatively in all eyes with endophthalmitis and vitreous opacities secondary to Behcet's disease. The surgery was completed without conjunctival and scleral suturing in all eyes. Mean intraocular pressure (IOP) was 17.2 mmHg (range 10-26 mmHg) preoperatively, 12.4 mmHg (range 6-24 mmHg) on the first postoperative day, 16.6 mmHg (range 10-33 mmHg) at 1 week, and 15.4 mmHg (range 10-20 mmHg) at 1 month postoperatively. On the first postoperative day, IOP was below 10 mmHg (between 6 and 9 mmHg) in 12 eyes (16.9%). In these eyes, IOP was normalized within 1 week without affecting the visual outcome. Five eyes (7%) had transient increase of IOP controlled by topical antiglaucomatous medications. Vitreous washout using 25-gauge TSV system was performed in two eyes, in which vitreous hemorrhage recurred. The TSV system was observed to be feasible, effective, and safe for a variety of vitre o retinal diseases. This minimally invasive and completely sutureless (transconjunctival) technique appears to decrease the convalescence period, operating time, and postoperative inflammatory response, and improve patient comfort.

Intraoperative Breakage of 20-Gauge Tano Forceps

To report three cases with breakage of a 20-gauge kryptonite forceps during vitreoretinal surgery. Interventional case report. Pars plana vitrectomy that included a membrane peeling was performed in three patients through standard ports with 20-gauge vitrectomy systems. The peeling procedure was attempted with the end-gripping kryptonite forceps. Intraoperatively, the branch/tip broke and dropped onto the posterior pole. Removal of the broken part was uncomplicated, and the subsequent clinical course was unremarkable. In one case, the handle and branch/tip part were exchanged inadvertently. In the other two cases, neither an exchange nor a maladaptation of the parts was noted. An exchange of the hand piece and gripping end may increase the risk of breakage and retinal damage. The delicate gripping tips, however, may break because of inadequate maintenance and/or aging of the material. Intraoperative visual and functional examination is recommended before intraocular use.

Corneal Topographic Changes After Transconjunctival (25-gauge) Sutureless Vitrectomy

To evaluate the topographic changes in the cornea after pars plana vitrectomy (PPV) with 25-gauge transconjunctival sutureless vitrectomy (TSV) system. Prospective, interventional case series. In this prospective study, we evaluated the topographic changes of the cornea in 32 eyes of 32 patients who underwent PPV with the 25-gauge TSV system. The topographic parameters that were analyzed statistically were the average corneal power, corneal surface cylinder, surface asymmetry index, and surface regularity index. Mean induced astigmatism was estimated by vector analysis software. Wilcoxon test was used for statistical analysis. There was no significant change in average corneal power, corneal surface cylinder, surface asymmetry index, and surface regularity index parameters at first day, first week, and first month after the operation. Mean induced astigmatism was 0.38 diopters at 15 degrees. Corneal surface and astigmatic changes were observed to be insignificant in the early postoperative period after PPV with the 25-gauge TSV system.

25‐Gauge transconjunctival sutureless vitrectomy system in the surgical management of children with posterior capsular opacification

To evaluate the safety and efficacy of the 25-gauge transconjunctival sutureless vitrectomy (TSV) system in the surgical management of posterior capsular opacification (PCO) in pseudophakic children. Pars plana membranectomy was performed for PCO in 10 pseudophakic eyes of six children (mean age 35.1 +/- 37.8 months; range 6-93 months) using the TSV system. Surgical technique, intraoperative problems and postoperative complications including wound leakage, hypotony and the need for suturing were recorded. Wound leakage and other intraoperative problems were not noted in any of the eyes. All eyes showed improvement of visual acuity from a mean of 6/67 before to 6/29 after surgery (P = 0.001). Mean postoperative intraocular pressure (IOP) was 7.8 +/- 3.1 mmHg (range: 3-10 mmHg). Four eyes (40%) had hypotony on the first postoperative day (IOP: 3-5 mmHg), which was transient in three eyes. One eye in a patient with uveitis had persistent hypotony, but hypotony was also present preoperatively, and the postoperative IOP returned to preoperative levels. This eye also developed recurrent PCO and a second capsulotomy was performed using the 25-gauge TSV system. Posterior capsulotomy using the 25-gauge TSV system appears to be a safe and effective approach in the management of PCO in pseudophakic children. Advantages include easier manipulation with the smaller instruments in these small eyes, and it can be considered in appropriate cases.

The Accuracy of Endoscopic Ultrasound (EUS)-Guided Fine Needle Aspiration (FNA) for Diagnosing Solid Pancreatic Lesions Using a New 25-Gauge Needle System

Introduction: EUS-FNA has enhanced our ability to diagnose pancreatic masses. Most of the published data is based on the use of a 22-gauge needle. The aim of this study was to evaluate our center's experience with a new disposable 25-gauge needle system in the diagnosis of solid pancreatic lesions. Methods: Our institution began utilizing this FDA approved 25-gauge EUS-FNA needle system (Echotip, Wilson Cook, Winston Salem, NC) in 2/2001. All patients referred for EUS evaluation of solid pancreatic mass between 2/2001 and 12/2002 were reviewed. Patient demographics, clinical history including follow-up, and pathology findings were recorded. Cytopathology was compared with operative histopathology in patients who had surgery. Patients who did not have surgery were followed clinically. Results: A total of 163 patients (mean age 66, 88 M/75 F) underwent EUS-FNA for solid pancreatic lesions using the 25-gauge needle. FNA was consistent with pancreatic malignancy in 48% (78/163) while 45% (74/163) had no evidence of malignancy. In the remaining 7% (11/163), biopsy was inconclusive. No complications were reported. Of the pancreatic cancer patients, 96% (75/78) had adenocarcinoma and 4% (3/78) had other malignancies. In the group with a definitive FNA diagnosis, 14% (23/163) underwent surgery and operative histopathology was compared with FNA cytopathology. There was one false-negative and no false-positive diagosis; and the sensitivity, specificity, PPV, and NPV were 94%, 100%, 100%, and 86% respectively. In the false-negative case, patient had cytologic evidence of chronic pancreatitis. In patients with an inconclusive FNA, 27% (3/11) had surgery and 2 had adenocarcinoma. The remaining 84% (137/163) of patients who did not undergo surgery were followed clinically. The mean survival for patients with a positive, negative, and inconclusive FNA was 11, 23, and 14 months respectively. Conclusions: 1. EUS-FNA using a 25-gauge needle system can accurately and safely provide a cytologic diagnosis of pancreatic masses. 2. The patient who had a false-negative FNA diagnosis had chronic pancreatitis, confirming previous reports that cytologic evaluation of pancreatic tissue in the setting of chronic inflammation can be difficult. 3. Studies with larger sample size and randomized arms are now needed to further assess the accuracy and complication rate of this smaller needle system.

A new 25-gauge instrument system for transconjunctival sutureless vitrectomy surgery

Objectives To introduce and evaluate the infusion and aspiration rates and operative times of the 25-gauge transconjunctival sutureless vitrectomy system (TSV) Design In vitro experimental and comparative interventional study. Participants and controls Twenty eyes of 20 patients underwent a variety of vitreoretinal procedures using the 25-gauge TSV, including idiopathic epiretinal membrane (n = 10), macular hole (n = 4), rhegmatogenous retinal detachment (n = 3), branch retinal vein occlusion (n = 2), diabetic vitreous hemorrhage (n = 1), and 20 cases similar in diagnosis and severity were matched to provide comparison between duration of individual portions of the surgical procedures with the existing 20-gauge vitrectomy system. Methods Description of the 25-gauge TSV is provided; infusion and aspiration rates of the 25-gauge and standard 20-gauge vitrectomy system were measured in vitro using balanced saline solution and porcine vitreous for several levels of aspirating power and bottle height, and operating times of individual portions of surgical procedures were measured for the 25-gauge and 20-gauge vitrectomy system. Main outcome measures Infusion, aspiration rates, and operative times of the 20-gauge and 25-gauge vitrectomy system. Results Infusion and aspiration rates of the 25-gauge TSV system were reduced by an average of 6.9 and 6.6 times, respectively, compared with the 20-gauge system when balanced saline solution was used. The average flow rate of the Storz 25-gauge cutter (at 500 mmHg, 1500 cuts per minute [cpm]) was 40% greater than that of the 20-gauge pneumatic cutter (at 250 mmHg, 750 cpm) but about 2.3 times less than the 20-gauge high-speed cutter (at 250 mmHg, 1500 cpm). Mean total operative time was significantly greater for the 20-gauge high-speed cutter (26 minutes, 7 seconds) than for the 25-gauge vitrectomy system (17 minutes, 17 seconds) ( P = 0.011). Conclusions Although the infusion and aspiration rates of the 25-gauge instruments are lower than those for the 20-gauge high-speed vitrectomy system, the use of 25-gauge TVS may effectively reduce operative times of select cases that do not require the full capability of conventional vitrectomy.

583 Scaling-up Heat-balance Sap Flow Sensors for the High Flow Rates of Mature Grape Vines

Management strategies like “deficit irrigation” in wine grapes require accurate, reliable information on vine water use, making direct measurements of vine transpiration highly desirable. The heat-balance sap flow method has the advantages of being non-invasive and requiring no other calibration beyond a zero-flow set. Potential violations of the method's assumptions were dealt with and the heat balance method successfully applied to mature grape vines under conditions of extremely high sap flow. Greenhouse studies suggested that vines transpire at night, up to 9.5% of the total 24-h water loss, thus violating the zero-flow assumption for setting the gauge constant. Using a predetermined gauge constant caused smaller errors than using daily, pre-dawn constants set in situ. The steady-state assumption was violated only in early and late hours of the day, and the inclusion of a term to account for the change in heat stored by the stem only marginally improved daily estimates of water use. The assumption of radially uniform temperature across the heated stem segment is violated at very high flows (e.g., &gt;700 g·h–1), but can be corrected for by using wider heaters and adjusting the placement of thermocouples. For a mature, potted vine in the greenhouse, the maximum absolute error in cumulative daytime water use between a sap gauge and a precision load cell was about –10%, with the gauge almost exclusively underestimating water loss. A custom-built, 20-gauge system was run continuously in the field for 90 days. Vine-to-vine variability in water use was not accounted for by normalizing sap flow by leaf area, suggesting that it is critical to include in any field study the largest number of gauges that are technically feasible.

On gas burners, gas pressure regulators and governor burners, gas globes and globe holders, and gas fixtures

We describe a technique for the penetrating keratoplasty (PKP) triple procedure that uses 29-gauge dual-chandelier illumination during creation of a non-open-sky continuous curvilinear capsulorhexis (CCC). The chandeliers are inserted through the pars plana into the vitreous cavity through the bulbar conjunctiva at the 3 o'clock and 9 o'clock positions. We compared this approach with that of a core vitrectomy, in which a single 25-gauge port is inserted into the vitreous cavity transconjunctivally through the upper temporal pars plana. The area of halation around the corneal opacity was significantly smaller in the 29-gauge group than in the 25-gauge group. The reduction in halation improved visibility of the anterior capsule and enabled the surgeon to perform CCC with greater safety. The 29-gauge chandelier system was more suitable than the 25-gauge chandelier system for the non-open-sky CCC component of the PKP triple procedure.