Incidence of Intraocular Pressure Spike and Other Adverse Events after Vitreoretinal Surgery

Accuracy of Intraocular Pressure Measurements of Eyes with Therapeutic Contact Lenses after Vitrectomy

Purpose: To evaluate the accuracy of intraocular pressure (IOP) measurements obtained by a rebound and non-contact tonometer in eyes with a therapeutic contact lens (CL) after vitrectomy.Methods: In 60 eyes of 60 patients who underwent vitrectomy for vitreoretinal disease, IOP was measured using a rebound tonometer (iCare ic200®; IOPRT) and non-contact computerized air puff tonometer (CT-80, IOPNCT), before and after wearing a CL (Purevision2®, +0.0 diopter). The mean IOP of three consecutive measurements were analyzed, and a comparative analysis with IOP measured by a Goldman applanation tonometer (IOPGAT) was performed.Results: The mean IOPRT without and with the CL was 12.55 ± 5.43 and 13.12 ± 5.13 mmHg, respectively, showing a statistically significant difference (p = 0.02) and strong positive correlation (r = 0.90, p < 0.001). The mean IOPNCT with and without the CL was 12.18 ± 3.24 and 12.17 ± 3.14 mmHg, showing no statistically significant difference (p = 0.17). The consistency with IOPGAT (12.57 ± 5.22 mmHg) was highest in IOPRT without the CL, followed by IOPRT with the CL, IOPNCT without the CL, and IOPNCT with the CL (intraclass correlation coefficients = 0.955, 0.945, 0.856, and 0.850, respectively). In addition, the rebound tonometer successfully measured IOP, regardless of whether the CL was worn; however, the non-contact tonometer failed to measure IOP in seven eyes without the CL and nine with the CL. No difference was observed according to intraocular tamponade type.Conclusions: A rebound tonometer can be used as an alternative IOL measuring method in eyes for which it is difficult to use a Goldman applanation tonometer due to the postoperative presence of a therapeutic CL.

Hypotony Following Intravitreal Silicone Oil Removal in a Patient With a Complex Retinal Detachment With Giant Retinal Tear

Postoperative ocular hypotony after silicone oil removal in complex cases of retinal detachment is a complication that can occur in about 20% of cases and can prevent the successful management of retinal detachments. Thus, it is critical to understand the mechanisms of hypotony and the potential interventions that can be done in order to avoid irreversible tissue damage. We present a case of a 35-year-old man who underwent intraocular surgery for removal of silicone oil tamponade following a combined scleral buckling and pars plana vitrectomy (PPV) surgery for a rhegmatogenous retinal detachment associated with a giant retinal tear. On Day 1 after the operation, the patient was found to have hypotony with optic disc edema, chorioretinal folds, and visual acuity of ‘hand movement’ perception. Two weeks postop, the patient’s condition stabilized, with a visual acuity of 0.38 logMAR, an intraocular pressure (IOP) of 12 mmHg, and the absence of macular edema.

[Intraocular pressure elevation after vitrectomy-Goldmann applanation tonometry measures lower intraocular pressure than dynamic contour tonometry]

Hintergrund

Das dynamische Konturtonometer PASCAL (DCT) ist ein digitales, der natürlichen Hornhautgeometrie angepasstes Kontakttonometer. Verglichen wurde das DCT mit dem Goldmann-Applanationstonometer (GAT).

Methodik

In einer prospektiven Querschnittstudie wurden 100 Augen vor und nach Pars-plana-Vitrektomie (ppV) vergleichend mit dem GAT und DCT gemessen. Verwendete Endotamponaden waren verschiedene Gase und Silikonöle. Erfasst wurden der präoperative intraokulare Druck (IOD), postoperative Druckveränderungen und die Intertonometerdifferenz.

Ergebnisse

Präoperativ lag der mittlere IOD mit dem GAT gemessen bei 15,8 ± 5,2 mm Hg und dem DCT bei 17,5 ± 5,9 mm Hg. Am ersten postoperativen Tag stieg bei Augen, die mit Gas versorgt wurden, der Druck im Mittel um 2,5 mm Hg (p = 0,035) an. Das DCT erfasste 18 Augen (19,1 %) mit einem postoperativen IOD von ≥ 25 mm Hg. Postoperativ maß das GAT den IOD im Schnitt 2,5 mm Hg niedriger und bei expansiver Gasendotamponade im Mittel um 3,0 mm Hg niedriger als das DCT. Bei IOD-Werten von postoperativ über 20 mm Hg lag das GAT im Mittel 4,7 mm Hg unter dem DCT. Zehn von 18 Augen mit IOD ≥ 25 mm Hg wurden mit dem GAT nicht als hypertensiv (≥ 25 mm Hg) erkannt. Bei 13 % maß das DCT am 1. postoperativen Tag einen um mindestens 6 mm Hg höheren IOD als das GAT. In einem Extremfall wurde der IOD mit dem GAT bei Gasendotamponade um 12 mm Hg unterschätzt.

Schlussfolgerung

Postoperative Druckanstiege nach ppV sind gefürchtete Komplikationen und können zu irreversiblem Visusverlust führen. Abhängig von der verwendeten Endotamponade misst das GAT den IOD niedriger als das DCT – besonders bei Druckspitzen durch expansive Gase. Die postoperative IOD-Messung nach ppV ist bedeutend und die Messwerte von GAT und DCT können abweichen.

Incidence of Management Changes at the Postoperative Day One Visit After Pars Plana Vitrectomy for Retinal Detachment

PURPOSE

To evaluate the incidence of unexpected management changes on the first day after pars plana vitrectomy (PPV) for retinal detachment repair.

DESIGN

Retrospective cohort study.

METHODS

The medical and billing records of a large academic private practice were electronically queried for all cases of PPV for retinal detachment performed between January 1, 2017, and December 31, 2017. All cases of PPV for rhegmatogenous or tractional retinal detachment with completed postoperative day 1 (POD1) and postoperative week 1 (POW1) visits were included. The preoperative consultation, operative report, and POD1 and POW1 (postoperative days 5-14) visits were reviewed. Main outcome measures were incidence of unexpected management changes (change in or extended positioning, additional procedure, change in drop regimen, or shortened interval follow-up) at the POD1 visit after uncomplicated PPV for retinal detachment.

RESULTS

Overall, 418 surgeries from 364 eyes and 355 patients were included. Eleven cases (2.6%) had an intraocular pressure (IOP) over 30 mm Hg at POD1. IOP-lowering drops were prescribed for 30 cases (7.2%). Silicone oil tamponade was positively associated with high IOP at POD1 (relative risk = 3.23, 95% confidence interval 0.96-10.84, P = 0.06). No additional management changes were made besides treating elevated IOP.

CONCLUSIONS

Management changes on POD1 after vitrectomy for retinal detachment repair are relatively uncommon and were solely IOP related in this patient group. There may be flexibility regarding the type of POD1 encounter necessary, including an IOP check with an ophthalmic technician or non-retinal eye care provider. Larger, prospective studies are needed to better determine the most efficient follow-up routine.

[The role of vitreous body in pathogenesis of glaucoma]

This literature review provides modern information on the unique structure of the vitreous body, its functions, and its role in the pathogenesis of glaucoma, describes the features of the vitreous morphology and metabolism, notes its biomechanical and trophic functions, outlines its role in healthy hydrodynamics and hemodynamics of the eye, as well as in aqueous humor outflow. The review presents clinical observations on the association of pathological changes in the vitreous body with glaucoma development and examines the role of involutional changes in the vitreous in the pathogenesis of glaucoma. The article also discusses possible pathogenetic mechanisms of glaucoma development in terms of pathological changes in the vitreous.

[Distinctive features of phacoemulsification in previously vitrectomized eyes]

The review presents the main pathogenetic mechanisms of cataract development in an avitic eye as well as anatomical and functional changes of the eye in the state of avitria. The authors have also analyzed distinctive behavior of such eyes during phacoemulsification and surgical techniques used to answer specific avitreal phenomena.

Incidence and outcomes of ocular hypertension from rhegmatogenous retinal detachment surgery in the acute postoperative setting

Purpose

To determine the incidence of ocular hypertension following surgery for rhegmatogenous retinal detachment in the first 3 months postoperatively and to determine their outcomes in terms of visual acuity, control of IOP, and changes in cup:disc ratio.

Patients and methods

A single center prospective cohort study was done involving patients who underwent retinal surgery for rhegmatogenous retinal detachment. The patients were followed up for 3 months postoperatively and were monitored for development of ocular hypertension. The primary outcome measures were changes in IOP, visual acuity, and cup:disc ratio.

Results

Of the 52 eyes enrolled in the study, 19 eyes developed ocular hypertension in the first 3 months postoperatively, giving an incidence rate of 36.5% (95% CI, 48.9-76.0%). Analysis of mean IOP trends shows that most cases of IOP elevations occur in the first day postoperatively with a sustained elevation up to the first month and then returning to normal levels by the 3rd month. There is a significant increase in mean cup:disc ratio among patients who developed ocular hypertension (p=0.047). Visual acuity trends show that mean visual acuity significantly improved from baseline among cases who maintained normal IOP (p=0.002) as compared to those who developed ocular hypertension (p=0.97), although the difference in final visual acuity at the end of 3 months between groups was not statistically significant (p=0.30).

Conclusion

Ocular hypertension may complicate retinal reattachment surgery. Control of IOP in the acute setting is essential to prevent development of secondary glaucoma.

Retina and glaucoma: surgical complications

Background

The close structural and microcirculatory co-relation between anterior and posterior segments of eye make them very vulnerable to complications when one of them is affected surgically. With the advent of anti-fibrotic agents in the management of glaucoma, the rates of vitreoretinal complications have become more frequent.

Main body

Common retinal complications after glaucoma surgeries include choroidal detachment; ocular decompression retinopathy; haemorrhagic choroidal detachment; hypotony maculopathy; malignant glaucoma; vitreous haemorrhage; bleb endophthalmitis; retinal detachment. Similarly, intraocular pressure rise is often noted after scleral buckle; pars plana vitrectomy; intravitreal gas injection; silicone oil injection; intravitreal steroid injection.

Conclusion

The article provides some insight into some of the complications after glaucoma and retina surgeries, including the pathogenetic mechanisms behind each complication and available management options.

The Risk of Primary Open-Angle Glaucoma Following Vitreoretinal Surgery-A Population-based Study

PURPOSE

To determine the risk of primary open-angle glaucoma (POAG) following vitreoretinal surgery.

DESIGN

Retrospective, population-based cohort study.

METHODS

All residents of Olmsted County, Minnesota, undergoing scleral buckle and/or vitrectomy between 2004 and 2015 were included in the operative cohort. The fellow nonoperative eyes were included in the comparison cohort. The study and comparison cohorts consisted of 344 and 277 eyes, respectively. The main outcome measure was the development of POAG. Secondary glaucomas were excluded. The probability of glaucoma in operative eyes and nonoperative fellow eyes was compared. The observed rate of POAG in the operative eyes was also compared to the rate of POAG in the population of Olmsted County.

RESULTS

The mean age was 64.7 years and the median follow-up period was 4.9 years. There were 58, 57, and 229 study eyes in the scleral buckle, scleral buckle with vitrectomy, and vitrectomy only cohorts, respectively. The 10-year cumulative probability of developing glaucoma was significantly greater in the operative group (8.9%, 95% confidence interval [CI] 3.8%-14%) compared to the nonoperative group (1.0%, 95% CI 0-2.4%; P = .02). None of the eyes in the scleral buckle group developed glaucoma. The 10-year probability of POAG was 17.5% (95% CI 0-34.9%) and 10.0% (95% CI 3.0%-17.0%) in the scleral buckle with vitrectomy and vitrectomy alone cohorts, respectively. The rates of POAG in operative eyes undergoing scleral buckle with vitrectomy and vitrectomy alone were significantly greater than the rate of POAG for the Olmsted County general population (1.0%, P < .001).

CONCLUSIONS

The risk of POAG is increased after vitrectomy.

Goldmann Applanation Tonometry versus Dynamic Contour Tonometry after Vitrectomy with Silicone Oil Endotamponade

PURPOSE

To evaluate the agreement of intraocular pressure (IOP) measurements using dynamic contour tonometry (DCT) and Goldmann applanation tonometry (GAT) in eyes after vitrectomy with silicone oil endotamponade and controls.

METHODS

In this prospective comparative study, IOP was measured with GAT and DCT in 30 eyes with oil endotamponade 1-3 days after vitrectomy and 40 untreated controls. In addition, ocular pulse amplitude (OPA), corneal pachymetry (CCT), and axial length (AL) were measured.

RESULTS

GAT values in the oil group were significantly higher compared to control eyes (mean GAT oil 13.6 ± 5.1 mmHg; mean GAT control 10.8 ± 2.1 mmHg; p = 0.003). There was no significant difference in DCT measurements (mean DCT oil 12.0 ± 4.1 mmHg; mean DCT control 11.9 ± 2.9 mmHg; p = 0.9). This led to a significant difference of GAT-DCT between the oil and control group (mean difference of GAT-DCT oil 1.6 ± 4.7 mmHg; mean difference of GAT-DCT control -1.1 ± 2.6 mmHg; p = 0.004). The difference between GAT and DCT was negatively correlated with the mean IOP measured by both methods (r = -0.36, p = 0.02) and positively correlated with CCT only in the control group (r = 0.36, p = 0.02), as well as to AL only in the oil group (r = 0.46, p = 0.01). The OPA did not differ significantly between groups.

CONCLUSION

GAT and DCT showed a good agreement in control eyes. The difference of GAT and DCT is significantly changed in eyes after vitrectomy with silicone oil endotamponade. Our findings suggest that GAT overestimates IOP in this situation.

Secondary Angle-Closure Glaucoma Due to Posterior Synechiae of Iris Following Combined Phacoemulsification and 23-Gauge Transconjunctival Vitrectomy

PURPOSE

To describe the clinical characteristics of eyes with secondary angle-closure glaucoma following combined phacovitrectomy.

METHODS

Retrospective case series.

RESULTS

Nine eyes developed angle-closure glaucoma due to iris posterior synechiae with an incidence rate of 1.82% (95% CI: 0.64 - 3%) among 493 eyes following phacovitrectomy. PDR with TRD was the most common surgical indication. Single piece IOL insertion and silicone oil were present in all cases. Fibrin in the anterior chamber was found in six eyes postoperatively. Mean degree of iris bombe was 310±79.37° at 3.55±1.87 weeks with a mean IOP of 32.56±5.89 mm of Hg. Systemic diabetes and grade of cataract were the only significant risk factors (r² =1; p= 0.016 and 0.049, respectively). Nd:YAG laser PI relieved the angle-closure attack in all cases.

CONCLUSION

Systemic diabetes and advanced grade of cataract are significant risk factors for secondary angle-closure glaucoma following combined phacovitrectomy.

[Structural and functional characteristics of vitrectomized eyes]

The article describes the potential effects of vitrectomy on clinical refraction, refraction of the cornea and its biomechanical parameters, the state of the lens, intraocular pressure, and biometric parameters of the anterior eye segment.

Prevalence of comorbid retinal disease in patients with glaucoma at an academic medical center

Background

Patients with various retinal diseases and patients who have undergone retinal procedures and surgeries have an increased risk of developing ocular hypertension and glaucoma. Little is known about the epidemiology of comorbid retinal diseases in glaucoma patients. This study evaluated the prevalence of retinal comorbidities in a population of patients with five types of glaucoma.

Methods

A longitudinal, retrospective study was conducted using International Classification of Disease (ICD-9) billing records from 2003 to 2010 at an academic medical center. Patients were classified as having primary open-angle glaucoma (POAG), low tension open-angle glaucoma (NTG), pigmentary open-angle glaucoma, chronic-angle closure glaucoma (CACG), or pseudoexfoliation glaucoma (PXG) if they had at least three clinic visits with the same ICD-9 code. Patients were classified as having a retinal comorbidity if they had two visits with the same code. Variables were analyzed with the independent t-test, χ² test, analysis of variance, or Fisher’s exact test.

Results

A total of 5,154 patients had glaucoma, and 14.8% of these had a retinal comorbidity. The prevalence of comorbid retinal disease was higher in patients with POAG (15.7%) than in those with NTG (10.7%), PXG (10.1%), or pigmentary open-angle glaucoma (3.7%; P<0.05). Two hundred and two patients had diabetic retinopathy, with POAG patients (4.5%) having a higher prevalence than those with CACG (1.4%) or PXG (0.6%; P<0.001). There were 297 patients who had macular degeneration and both POAG (2.0%) and PXG patients (2.9%) had a higher prevalence of nonexudative macular degeneration than those with CACG (0%; P<0.01). Patients with comorbid retinal disease had a higher prevalence of blindness and low vision than those without comorbid retinal disease (1.97% versus 1.02%, P=0.02).

Conclusion

The high prevalence of comorbid retinal disease and the nearly twofold increase in blindness and low vision in this population demonstrate the need for ophthalmologists to determine if patients have multiple etiologies for their vision loss. The higher prevalence of certain retinal diseases in POAG patients may reflect common pathophysiological processes that warrant further investigation.

Combined 23-gauge sutureless vitrectomy and clear corneal phacoemulsification for rhegmatogenous retinal detachment repair

AIM

To assess the outcomes of combined 23-gauge sutureless vitrectomy and clear corneal phacoemulsification with intraocular lens implantation for rhegmatogenous retinal detachment (RRD) repair.

METHODS

This was a retrospective, consecutive, non-comparative, interventional case series of 30 eyes of 30 patients who underwent combined sutureless vitrectomy and clear corneal cataract surgery for the repair of RRD. The principal outcome measures were primary anatomical success rate, reasons for redetachment, final visual acuity, and surgical complications.

RESULTS

Primary reattachment was achieved in 27 eyes (90.0%). The reasons for redetachment (3 eyes, 10%) were incomplete laser retinopexy, persistent chronic subretinal fluid, and proliferative vitreoretinopathy, respectively. The logarithm of the minimum angle of resolution visual acuity (mean±SD) improved from 0.76±0.74 preoperatively to 0.21±0.37 6 months' postoperatively (P<0.0001). Postoperative hypotony was not detected, but 1 eye (3.3%) had increased intraocular pressure (30mmHg) with spontaneous resolution. No endophthalmitis developed during follow-up. Macular pucker was detected in 3 eyes (10.0%).

CONCLUSION

Combined 23-gauge sutureless vitrectomy and clear corneal phacoemulsification with intraocular lens implantation for RRD repair was proven safe and effective. It may provide not only the known advantages of conventional combined surgery, but also additional advantages such as less conjunctival fibrosis and the maintenance of stable intraocular pressure with low risks of postoperative hypotony and intraocular pressure elevation.

Changes in day 1 post-operative intraocular pressure following sutureless 23-gauge and conventional 20-gauge pars plana vitrectomy

Background/Aims:

The benefits associated with transconjunctival sutureless vitrectomy techniques are continuing to be defined. The purpose of this study was to compare the incidence of extreme changes in day 1 intraocular pressure (IOP) following 23-gauge sutureless vitrectomy compared with conventional 20-gauge vitrectomy.

Methods:

Fifty consecutive 23-gauge and 50 consecutive 20-gauge cases were included; eyes with a history of previous vitreoretinal surgery were excluded. 23-gauge surgery was completed with passive fluid air exchange where no long acting tamponade was indicated. The surgery remained sutureless unless a leak was visible at the end of the procedure. Data were collected by retrospective case note review. Statistical analysis was carried out using Fisher’s exact and chi-square tests.

Results:

Twenty-two percent (11/50) of 23-gauge vitrectomies required suturing of one or more ports. On the first post-operative day hypotony (IOP<5mmHg) occurred in 1/50 eyes in the 20- and 23-gauge groups. Raised pressure (IOP>21mmHg) occurred in 30% (15/50) of eyes in the 20-gauge group and 8% (4/50) of eyes in the 23-gauge group; IOP>30mmHg only occurred in the 20-gauge group (3/50).

Conclusion:

Fluid air exchange following 23-gauge vitrectomy is associated with very low risk of day 1 hypotony. This predominantly sutureless technique appears to reduce the incidence and magnitude of early post-operative IOP elevation compared with conventional 20-gauge vitrectomy.

Course of intraocular pressure after vitreoretinal surgery: is early postoperative intraocular pressure elevation predictable?

PURPOSE

Assessment of intraocular pressure (IOP) after vitreoretinal surgery is important to ensure functionality of the eye. Incidences and risk factors for early postoperative IOP elevation were evaluated.

METHODS

In a prospective case series of 210 vitreoretinal cases, IOP-lowering treatment was performed at IOP values of ≥30 mmHg. Differences in IOP elevation in relation to surgical procedures and tamponades were evaluated.

RESULTS

Sixty-two patients required treatment (29.5%). Encircling bands were associated with a high risk for IOP elevation when combined with pars plana vitrectomy and gas tamponade (37.9%) or oil tamponade (50.0%). Panretinal laser photocoagulation in conjunction with oil tamponade for proliferative diabetic retinopathy traction retinal detachment (RD) resulted in the highest risk for IOP increases (83.3%). Intraocular pressure elevation in proliferative diabetic retinopathy traction RD often evolved 4 hours after vitreoretinal surgery compared with 8 hours to 12 hours after vitreoretinal surgery in rhegmatogenous RD. Silicone oil removals (7.1%) and external buckling procedures (0.0%) carried low risks for IOP increases.

CONCLUSION

Patients treated for proliferative diabetic retinopathy traction RD and for primary rhegmatogenous RD were at high risk for prolonged IOP elevation. These groups also required medical retreatment most often and should therefore be closely monitored. Care must be taken not to overlook delayed IOP elevations.

Intravitreal Fluorinated Gas Preference and Occurrence of Rare Ischemic Postoperative Complications after Pars Plana Vitrectomy: A Survey of the American Society of Retina Specialists

Objective. To perform a survey of the American Society of Retina Specialists (ASRS) regarding the use of vitreous cavity fluorinated gas as an adjunct to pars plana vitrectomy for retinal detachment or macular hole repair. Methods. A multiple-choice online questionnaire was administered to members of ASRS. Physician experience, gas preference for vitrectomy, and categorical estimate of observation of blinding postoperative ischemic events were recorded. Results. 282 questionnaires were completed. Mean years in vitreoretinal practice were 15 ± 10. A decrease in yearly vitrectomy volume was associated with increased number of years in practice (P = 0.011). Greater than 95% of respondents preferred fluorinated gas to air alone for both retinal detachment and macular hole repair. 38% of respondents reported at least one observation of a blinding ischemic postoperative event. Overall estimated incidence of blinding postoperative ischemic event was 0.06 events/year in practice. Conclusions. Currently, C3F8 and SF6 are the postoperative gas preference for ASRS respondents, in contrast to previous North American surveys. The occurrence of blinding ischemic events appears unrelated to number of years in practice, was reported by less than half of those surveyed, and has occurred at an infrequent rate of approximately once for every ten years of practice for those observing the phenomena.

Day 1 postoperative intraocular pressure spike in vitreoretinal surgery (VDOP1)

PURPOSE

To classify the clinical characteristics that might identify patients who may not require next-day follow-up following routine vitreoretinal intervention.

METHODS

Prospective case series.

RESULTS

The only statistically significant factors for raised intraocular pressure (IOP) were gas tamponade and preoperative raised IOP. 44.7% (17/38) of patients with preoperative IOP ≥ 20 mmHg had postoperative IOP ≥ 30 mmHg while 8.6% (17/197) of patients with preoperative IOP < 20 mmHg had postoperative IOP ≥ 30 mmHg (p = 0.0001). Phacoemulsification did not increase risk for a postoperative IOP spike. There was a 20-21% risk of postoperative IOP > 30 mmHg for patients with gas tamponade. All patients with no tamponade with IOP > 30 mmHg had preoperative IOP ≥ 20 mmHg.

CONCLUSION

Uncomplicated vitreoretinal procedures with preoperative IOP of< 20 mmHg and no gas tamponade are unlikely to have uncontrolled IOP spike at day 1.

Intraocular pressure changes after vitrectomy with and without combined phacoemulsification and intraocular lens implantation

PURPOSE

To determine sequential intraocular pressure (IOP) changes after pars plana vitrectomy (PPV) with or without combined phacoemulsification and intraocular lens implantation (PE & IOL).

METHODS

Consecutive patients who underwent PPV with PE & IOL (combined group) or without PE & IOL (vitrectomy group) were reviewed for postoperative sequential IOPs and the number of IOP lowering medications used. Of the 68 patients (68 eyes) who underwent simple PPV, 41 eyes were allocated to the vitrectomy group, and 27 eyes to the combined group.

RESULTS

The mean IOPs were higher on postoperative days one and two, as compared to preoperative values, in both groups. The mean IOP changes on postoperative day one (10.0 mmHg vs. 5.3 mmHg, p = 0.02) and day two (3.7 mmHg vs. 1.3 mmHg, p = 0.02) were significantly higher in the combined group.

CONCLUSIONS

Phacovitrectomy is associated with a higher risk of IOP elevation during the early postoperative period than PPV alone. Caution should be exercised in patients who are vulnerable to IOP fluctuations when combined surgery is indicated.

Impact of early rise of intraocular pressure on visual outcome following diabetic vitrectomy

Objective:

The objective was to study the incidence and risk factors for an early rise in intraocular pressure (IOP) following pars plana vitrectomy (PPV) for proliferative diabetic retinopathy (PDR) and to correlate its impact on visual outcome.

Materials and Methods:

This was a longitudinal prospective study. IOP and best corrected visual acuity (BCVA) for 73 cases of PDR (52 males and 21 females) who underwent PPV were recorded at day 1, week 1, and months 1, 3, and 6. Risk factors for the early IOP rise, defined as IOP ≥ 30 mmHg at day 1, were evaluated using cross-tabulation and the t-test.

Results:

Mean IOP at day 1 was 21.8 ± 9.8 mmHg with 15 cases (20.5%) having an early rise in IOP. Risk factors for the early IOP rise included intraoperative fibrovascular frond removal (P = 0.003), lens removal (P = 0.043), and intraoperative vitreous bleed (P = 0.008). The early rise in IOP was also associated with consistently raised IOP (P = 0.02), defined as IOP > 21 mmHg during first three consecutive follow-up visits. Further, difference in BCVA at 6 months among the two groups, i.e., with and without an early IOP rise was statistically significant (3.11 ± 1.52 logMAR vs. 2.11 ± 1.49 logMAR; P = 0.025).

Conclusion:

An early rise in IOP is a significant risk factor which compromises the visual outcome of patients undergoing diabetic vitrectomy.