Non-buckled vitrectomy for retinal detachment with inferior breaks and proliferative vitreoretinophathy

AIM: To investigate the efficacy of non-buckled vitrectomy with classical endotamponade agents in the treatment of primary retinal detachment (RD) complicated by inferior breaks and proliferative vitreoretinophathy (PVR).METHODS: A retrospective, consecutive and case series study of 40 patients with inferior break RD and PVR ≥C1 was conducted. All patients underwent a standard 3-port 20-gauge pars plana vitrectomy (PPV) with gas or silicone oil tamponade without supplementary scleral buckling. The vitreous and all proliferative membrane were completely removed, and retinectomy was performed when necessary. The mean follow-up was 12.5 months. The primary and final anatomic success rate, visual acuity and complications were recorded and analyzed.RESULTS: Primary anatomic success rate was achieved in 35 of 40 eyes (87.5%) and the final anatomic success rate was 100%. The most common cause of redetachment was recurrent PVR. The best-corrected visual acuity (BCVA) at final follow-up was improved in 34 eyes (85%), remained stable in 1 eye (2.5%), and worsened in 5 eyes (12.5%). The mean visual acuity at final follow-up was improved significantly (P=0.000).CONCLUSION: This retrospective study provides evidence that vitrectomy without scleral buckling seemed to be an effective treatment for inferior break RD with PVR. With complete removal of vitreous and proliferative membranes and timing of retinectomy, the inferior breaks which complicated with PVR could be closed successfully without additional scleral buckling.     

The incidence and the risk factors for iatrogenic retinal breaks during pars plana vitrectomy

Purpose

To establish the frequency and the risk factors for iatrogenic retinal breaks during three-port pars plana vitrectomy (PPV).

Methods

A total of 2471 PPV operations were included in the study. The study period was between 2001 and 2010, all the data were entered in an electronic patient record database. All 270 consecutive eyes of 270 patients developing iatrogenic retinal breaks during primary PPV were matched to 270 controls. Univariate and multivariate analysis were performed to establish the risk factors.

Results

The median age of the patients with iatrogenic breaks was 60.06 years; male to female ratio was 140/130. The overall frequency of iatrogenic retinal breaks was 10.09%. The frequency of iatrogenic retinal breaks for eyes undergoing PPV for tractional retinal detachment (TRD) was 32.45%. The lens status was phakic in 79.6% of the eyes, with iatrogenic breaks compared with 34.4% of the eyes in control group (P<0.001). Posterior vitreous was attached in 58.9% of the eyes with iatrogenic breaks compared with 50.4% of the eyes in control group (P=0.04). Internal limiting, epiretinal, proliferative, or fibrovascular membrane removing manoeuvers were performed in 71.1% of the eyes with iatrogenic breaks compared with 61.9% of the eyes in control group (P=0.052).

Conclusion

Eyes undergoing PPV for TRD had significantly higher frequency of iatrogenic retinal breaks compared with other subgroups (P=0.0001). Phakia and absence of PVD were found to be risk factors for iatrogenic retinal breaks.     

Surgical and visual outcome following 20-gauge vitrectomy in proliferative diabetic retinopathy over a 10-year period, evidence for change in practice

Introduction

The study reports 10-year anatomical and visual outcome in patients who underwent pars plana vitrectomy (PPV) for complications due to proliferative diabetic retinopathy (PDR).

Methods

Retrospective analysis of patients undergoing 20G PPV from January 1999 to May 2010 for tractional retinal detachment (TRD) and non-clearing vitreous hemorrhage (NCVH) secondary to PDR recorded prospectively on an electronic patient record. The primary aim was to study anatomical success and eyes with visual acuity (VA) of ≤0.3 logMAR at last follow-up.

Results

There were 346 eyes of 249 patients with mean age of 55.63 years and follow-up of 1.44 years. In all, 95.3% of eyes had a flat retina at final follow-up. Overall 136/346 (39.4%) eyes had final VA of logMAR ≤0.3 (Snellen 6/12) and 129 (37.3%) had logMAR ≥1.0 (Snellen 6/60). In all, 50/181 (27.6%) eyes with TRD and 84/165 (50.9%) with NCVH achieved final VA of ≤0.3 logMAR (Snellen 6/12). A total of 218 (63.1%) showed ≥0.3 logMAR improvement from baseline to last follow-up. Both preoperative VA and final postoperative (post-op) VA (P<0.001) improved significantly with each year from 1999 to 2010. The commonest peroperative complication was iatrogenic retinal tear formation (28.4%). This was a risk factor for the development of post-op retinal detachment, odds ratio: 3.90 (95% confidence interval: 1.91–7.97, P=0.0002). Silicone oil was used in 5.2% of patients at the primary procedure. In all, 9.2% required removal of non clearing post vitrectomy hemorrhage.

Conclusions

Outcomes from vitreoretinal surgery for complications of diabetic retinopathy have improved. In addition, the visual outcome after diabetic vitrectomy steadily improved over the 10-year period, which may in part be due to the move to operate on patients with better vision.     

预防性玻璃体切割手术治疗急性视网膜坏死综合征

目的:探讨预防性玻璃体切割手术对急性视网膜坏死综合征的治疗效果。方法:患者26例33眼分为两组,常规治疗组20眼接受常规治疗,包括抗病毒治疗、视网膜脱离发生后给予玻璃体切割手术治疗;及时玻璃体切割手术组13眼给予抗病毒治疗及预防性玻璃体切割手术治疗。术后患者随访6~48 mo。结果:在常规治疗组,发生视网膜脱离11眼(55%),眼球萎缩4眼(20%),视力提高者3眼(15%),预防性玻璃体切割手术治疗组,发生视网膜脱离1眼(8%),视力提高者5眼(38%)。预防性玻璃体切割手术组视网膜脱离发生率较常规治疗组低(P<0.05)。结论:预防性玻璃体切割手术可以有效地降低视网膜脱离的发生率,改善急性视网膜坏死综合征的预后。     

Retinal tears after posterior vitreous detachment and vitreous hemorrhage in patients on systemic anticoagulants

Aims or Purpose

To determine the rate of retinal tears (RTs) after posterior vitreous detachment (PVD) and vitreous hemorrhage (VH) in patients on systemic anticoagulants.

Methods

In all, 260 eyes of 260 patients with an acute PVD and VH were followed for evidence of an RT or detachment. Patients were divided into those taking systemic anticoagulants and those not taking anticoagulants.

Results

A total of 137 patients (53%) were taking anticoagulants, 123 (47%) were not. Overall, 72% of patients not taking any anticoagulant had evidence of an RT, whereas 46% of patients taking an anticoagulant had an RT (P-value 0.0002). Also, 37% of patients not taking an anticoagulant had a retinal detachment (RD), whereas 23% of patients taking any anticoagulant had an RD (P-value 0.01).

Conclusions

In patients with an acute PVD and VH using anticoagulants, RTs and RDs were common. Anticoagulation status may be an important contributing factor in predicting the incidence of an RT or detachment.     

Acute retinal necrosis in the United Kingdom: results of a prospective surveillance study

Background

To determine the incidence of acute retinal necrosis (ARN) in the United Kingdom and to describe the demographics, management, and visual outcome in these patients.

Methods

This was a prospective study carried out by the British Ophthalmological Surveillance Unit (BOSU) between September 2007 and October 2008. Initial and 6-month questionnaires were sent to UK ophthalmologists who reported cases of ARN via the monthly BOSU report card system.

Results

In all, 45 confirmed cases (52 eyes) of ARN were reported in the 14-month study period, giving a minimum incidence of 0.63 cases per million population per year. There were 20 females and 25 males. Age ranged from 10 to 94 years. Eight patients had a history of herpetic CNS disease. Aqueous sampling was carried out in 13 patients, vitreous in 27, and cerebrospinal fluid (CSF) in 4. Varicella-zoster virus followed by herpes simplex were the most common causative agents. Treatment in 76% of the cases was with intravenous antivirals; however, 24% received only oral antivirals. In all, 47% of patients had intravitreal antiviral therapy. Visual outcome at 6 months was <6/60 in 48% of the affected eyes.

Conclusion

The minimum incidence of ARN in the UK is 0.63 cases per million. Patients with a history of herpetic CNS disease should be warned to immediately report any visual symptoms. There is increased use of oral and intravitreal antivirals in initial treatment.     

Is day-1 postoperative review necessary after pars plana vitrectomy?

Purpose

This study aimed to determine the proportion of patients requiring alteration in management based on the findings of the day-1 postoperative visit after pars plana vitrectomy, and to identify clinical characteristics that predict the need for unexpected intervention.

Patients and methods

A retrospective case note review was conducted of all patients who underwent pars plana vitrectomy and who then attended for review on the first postoperative day. All patients received routine prophylactic anti-glaucoma medication.

Results

Two hundred and seventy-three patients examined on day 1 following vitrectomy were studied. Indications for surgery included retinal detachment, epiretinal membrane, macular hole, vitreous haemorrhage, diabetic eye disease, and floaters. Twenty-gauge (20G) vitrectomy was performed in 124 eyes (45%); 23-gauge (23G) vitrectomy was performed in 149 eyes (55%). Phacoemulsification was performed concurrently in 51/273 (19%) eyes. Ten patients (3.7%) required unexpected intervention on day 1 owing to intraocular pressure (IOP) >30 (2/273), IOP <6 (5/273), or unexpected return to theatre for anterior chamber washout (3/273). There was no difference in intervention rate or day-1 IOP between 20G and 23G cases. Hypotony was less common if gas tamponade was used (χ²-test, P<0.001). Patients undergoing combined phacoemulsification and 20G vitrectomy were significantly more likely to require intervention on day 1 than patients undergoing 20G vitrectomy alone (15.0 vs 1.9%, P=0.029, Fisher''s exact test) but this was not the case for patients undergoing 23G vitrectomy (0 vs 4.2%, Fisher''s exact test, P=0.58).

Conclusions

The intervention rate on the first day after vitrectomy is low and day-1 postoperative review can be safely omitted in the majority of patients undergoing vitrectomy.     

Effect of intravitreal bevacizumab injection before vitrectomy on proliferative diabetic retinopathy

AIM: To evaluate the effect of intravitreal bevacizumab (IVB) injection 1 week before pars plana vitrectomy (PPV) in proliferative diabetic retinopathy (PDR) patients. METHODS: A retrospective research was done on 46 PDR patients who were divided into PPV group (n=28) and IVB group (n =18, PPV with preoperative IVB). Bevacizumab was injected 1 week before PPV. Main outcome measures were visual acuity, incidence of iatrogenic retinal breaks, intraoperative and postoperative bleeding. RESULTS: At 1 month after surgery, visual acuity in PPV (82.1%) and IVB group (88.9%) improved significantly (P＜0.01) and the difference between the two groups was not significant (P＞0.05). Iatrogenic retinal breaks were reported in 18 cases (64.3%) in PPV group and 4 cases (22.2%) in IVB group (P＜0.05). Intraoperative bleeding was encountered in all cases in PPV group and 7 cases (39%) in IVB group (P＜0.01). Postoperative bleeding was reported in 9 cases (32.1%) in PPV group and none in IVB group (P＜0.01). CONCLUSION: IVB injection before PPV is helpful in reducing iatrogenic retinal breaks, intraoperative and postoperative bleeding in PDR patients.     

Ocular injuries from improvised explosive devices

Purpose

To document the characteristics, treatments, and anatomical and functional outcomes of patients with ocular trauma from improvised explosive devices (IEDs).

Methods

Retrospective review of ocular injuries caused by IEDs, admitted to our tertiary referral centre.

Results

In total, sixty-one eyes of the 39 patients with an average age of 24 years (range, 20–42 years) were included in the study. In total, 49 (80%) eyes of the patients had open-globe and 12 (20%) had closed-globe injury. In eyes with open-globe injury, intraocular foreign body (IOFB) injury was the most frequently encountered type of injury, observed in 76% of eyes. Evisceration or enucleation was required as a primary surgical intervention in 17 (28%) of the eyes. Twenty-two (36%) eyes had no light perception at presentation. Patients were followed up for an average of 6 months (range, 4–34 months). At the last follow-up, 26 (43%) of 61 eyes had no light perception. Postoperative proliferative vitreoretinopathy (PVR) developed in 12 (50%) of the 24 eyes that underwent vitreoretinal surgery, and four of these eyes became phthisical. There were no cases of endophthalmitis. The presence of open-globe injury and presenting visual acuity worse than 5/200 were significantly associated with poor visual outcome (<5/200, P<0.05). In eyes with open-globe injury, the presence of an IOFB was not associated with poor visual outcome (P>0.05).

Conclusion

Ocular injuries from IEDs are highly associated with severe ocular damage requiring extensive surgical repair or evisceration/enucleation. Postoperative PVR is a common cause of poor anatomical and visual outcome.     

Bevacizumab as an adjunct to vitreoretinal surgery for diabetic retinopathy in East Africa

Purpose

The purpose of this study is to evaluate the efficacy of preoperative intravitreal bevacizumab (IVB) for improving outcomes in vitrectomy for diabetic retinopathy-related non-clearing vitreous haemorrhage and/or tractional retinal detachment.

Methods

Medical record from patients undergoing vitrectomy for proliferative diabetic retinopathy (PDR) were retrospectively analysed (2003–2011). From 2007, IVB (1.25 mg 2–4 days before operating) was used on all eyes. Eyes receiving IVB were compared with those that did not receive IVB. Intraoperative complications, reoperation rates, and final visual acuity were the core outcome measures.

Results

Data were analysed for 88 patients (101 eyes). In all, 41 (41%) patients had received IVB, whereas 60 (59%) patients had not. Significant intraoperative haemorrhage occurred in six eyes (10%) in the non-IVB group and in one (2.4%) IVB eyes (P=0.24). Silicon oil was used in 29 (48%) non-IVB eyes and in 11 (27%) IVB eyes (P=0.03). The non-IVB eyes underwent significantly more vitreoretinal reoperations (P=0.01) and were significantly more likely to lose two or more lines of vision at the final follow-up (P=0.03). The numbers needed to treat (NNT) blindness (<3/60) was four for non-IVB eyes and two for the IVB group.

Conclusions

IVB reduces surgical complications, the use of silicon oil, and the need for further retinal surgery. The NNT to restore useful vision (≥3/60) to a blind eye were significantly lower in the IVB group. Vitreoretinal surgery for the complications of PDR is effective in an East African context, and IVB should be considered a valuable adjunct.     

Immediate intraocular pressure rise after intravitreal injection of ranibizumab and two doses of triamcinolone acetonide

AIM: To evaluate prospectively immediate intraocular pressure (IOP) changes after the intravitreal injection of ranibizumab, 2 and 4mg triamcinolone acetonide. METHODS: Patients who underwent intravitreal injection of 0.1mL (4mg) triamcinolone acetonide (TA, Group T4), 0.05mL (2mg) TA (Group T2) and 0.05mL (0.5mg) ranibizumab (Group R) comprised the study population. Overall, 229 eyes of 205 patients were injected. Fifty-four eyes (23.6%) were in Group T4, 69 eyes (30.1%) in Group T2 and 106 eyes (46.3%) in Group R. If IOP was less than 26mmHg immediately after the injection no further measurement was performed. If IOP was ≥26mmHg, IOP was remeasured till the reading was below 26mmHg at 5, 15 and 30 minutes. RESULTS: Immediately after the injection, the IOP of 28 eyes (51.9%) in Group T4, 22 eyes (31.9%) in Group T2 and 51 eyes (48.1%) in Group R were over 25mmHg. At 30 minutes, IOP of one eye (1.9%) in group T4, two eyes (2.9%) in group T2 and two eyes (1.9 %) in Group R were over 25mmHg. Immediate post-injection IOP was significantly higher in Group T4 and Group R when compared to Group T2 (P<0.001 and P<0.001, respectively). IOP was significantly higher in eyes without vitreous reflux when compared to those with vitreous reflux in all groups (P<0.001). CONCLUSION: IOP may remarkably increase immediately after the intravitreal injection of 2 or 4mg triamcinolone acetonide, and 0.5mg ranibizumab. Absence of vitreous reflux is the most important predicting factor for immediate IOP rise after the injection.     

Comparison of retinal thickness values and segmentation performance of different OCT devices in acute branch retinal vein occlusion

Purpose

To compare retinal thickness (RT) measurement and segmentation performance of time domain (TD, Stratus) and spectral domain (SD) optical coherence tomography (OCT) devices (Cirrus, Spectralis) for imaging macular oedema (ME) secondary to branch retinal vein occlusion (BRVO).

Methods

In this study, 20 eyes of 20 consecutive patients with acute BRVO were included. A total of 18 unaffected fellow eyes served as control group. RT measurement was analysed in the five inner fields of the early-treatment diabetic retinopathy grid, and proportional segmentation errors were evaluated.

Results

Central millimetre thickness (CMT) showed a mean difference of −64, −74, and −18 μm (P<0.001) in the control group and −31 μm (P=0.107), −92 μm (P<0.001), and −105 μm (P=0.016) in the BRVO group, between Stratus and Cirrus, between Stratus and Spectralis, and between Cirrus and Spectralis, respectively. Mean RT showed the highest variability between different devices in the area most intensively affected by BRVO-related ME. In eyes with BRVO, 14.6% of Spectralis, 20% of Stratus, and 36.6% of Cirrus scans demonstrated moderate and severe segmentation errors.

Conclusion

RT measurement in eyes with BRVO, by TD and SD OCT, is compromised by a significant rate of segmentation errors. Deviations are most pronounced in the areas most severely affected by ME.     

Conjunctival pigmentation after 23-gauge microincisional vitrectomy surgery

Aim

To investigate cases with conjunctival pigmentation originating from sclerotomy sites after 23-gauge microincisional vitrectomy surgery (MIVS).

Methods

This is a retrospective study comprised of 185 eyes from 185 consecutive patients who underwent 23-gauge MIVS. The authors investigated the incidence and the clinical factors associated with conjunctival pigmentation, including indication of vitrectomy and surgical procedures.

Results

Eight eyes (4.3%) from 185 eyes showed conjunctival pigmentation after surgery within 7 days postoperatively. Light microscopic examination of excised tissue showed infiltration of abundant dark brownish colored melanophages with surrounding scattered, finely granular, melanin pigments. C3F8 gas tamponade (OR, 9.4; 95% CI, 1.9–44.5; P=0.005) was significantly associated with conjunctival pigmentation. The mean surface area (21.26±2.21 mm²) of three eyes with C3F8 tamponade was significantly larger than that of five eyes (2.51±0.73 mm²) without tamponade (P=0.025). Neither leakage nor hypotony was found.

Conclusions

Intraocular melanin pigments could prolapse through the sclerotomy site and cause conjunctival pigmentation after 23-gauge MIVS. Thus, preoperative warning is necessary in patients with 23-gauge MIVS.     

Effect of Tetramethylpyrazine on RPE degeneration, choroidal blood flow and oxidative stress of RPE cells

AIM: To study the effects of Tetramethylpyrazine (TMP) on retinal pigment epithelium (RPE) degeneration, choroidal blood flow and oxidative stress of RPE cells. METHODS: The 35mg/kg NaIO3-induced RPE degeneration rat eyes was given 25μg 1% TMP eye drops 3 times a day for 7 days before NaIO3 injection, and then 2 to 4 weeks after NaIO3 injection. RPE function was measured with c-wave of electroretinogram (ERG). Colored microsphere technique was used for in vivo experiments to determine the choroidal blood flow in ocular hypertensive (40mmHg) rabbit eyes. Methylthiazoltetrazolium (MTT) assay was used to study in vitro effect of TMP on various oxidants induced injury in the hRPE (ARPE-19 (ATCC, Manassas, VA, USA)) . RESULTS: Two weeks after NaIO3 injection, the amplitude of ERG c-wave fell markedly in NaIO3 group to 36% of control group(P <0.01). No apparent difference was observed in TMP+NaIO3 group. Four weeks later, the NaIO3 group fell to 46% of control group (P<0.01), while the TMP+NaIO3 group fell to only 77% of control group (P<0.01). There was a 67% reversal of the ERG c-wave by TMP as compared to NaIO3 group(P<0.01). The choroidal blood flow was significantly increased at all time points (at 30, 60 and 120 minutes after TMP instillation) as compared with corresponding controls. TMP had no effect on hypoxia-(1%O2), t-BHP- and H2O2-induced damage in RPE cells. 10(g/mL TMP could reverse 1 and 3mM NaN3-induced loss of viability of RPE by 18.5% (P <0.01) and 23% (P<0.01), respectively. 30μg/mL TMP could reverse 30 and 100mM NaIO3 induced loss of viability of RPE by 18.1% (P <0.05) and 16.8% (P <0.01), respectively. CONCLUSION: TMP can significantly protect RPE from NaIO3 induced degeneration in vivo and oxidative stress in vitro and can increase choroidal blood flow markedly in vivo.     

Anatomical and functional outcomes in contusion injuries of posterior segment

Purpose

To evaluate the clinical features, and anatomical and visual outcomes in patients with closed-globe contusion injury involving the posterior segment.

Methods

Retrospective review of posterior segment contusion injuries admitted to our tertiary referral center.

Results

In all, 115 patients (115 eyes) with complete data were reviewed. Surgery had been performed in 79 (69%) patients. The mean follow-up period was 6 months (range, 2–34 months). Retinal detachment, in 31% of eyes, was the most frequently encountered posterior segment pathology. The presence of retinal detachment was associated with poor visual outcome (<20/100), (P<0.001). Coexisting (five patients, 4%) and postoperative proliferative vitreoretinopathy (PVR) (two patients, 2%) was the main cause of failure in these cases. A significant positive correlation was obtained between initial and final visual acuity levels in both the medical treatment group and the surgical treatment group (P<0.05). The presenting visual acuity of <20/400 was associated with poor visual outcome (P<0.05 for both groups). Poor visual outcome in 13 patients with successful repair of retinal detachment was due to the macular lesions and the optic atrophy.

Conclusion

Retinal detachment was the most frequently encountered posterior segment pathology subsequent to closed-globe contusion injuries. In addition to macular scarring and optic nerve damage, development of PVR has prognostic significance in these eyes.     

Pilot randomised controlled trial of face-down positioning following macular hole surgery

Objective

This was a pilot randomised controlled trial (RCT) to investigate the effect of post-operative face-down positioning on the outcome of macular hole surgery and to inform the design of a larger definitive study.

Methods

In all, 30 phakic eyes of 30 subjects with idiopathic full-thickness macular holes underwent vitrectomy with dye-assisted peeling of the ILM and 14% perfluoropropane gas. Subjects were randomly allocated to posture face down for 10 days (posturing group) or to avoid a face-up position only (non-posturing group). The primary outcome was anatomical hole closure.

Results

Macular holes closed in 14 of 15 eyes (93.3% 95% confidence interval (CI) 68–100%) in the posturing group and in 9 of 15 (60% 95% CI 32–84%) in the non-posturing group. In a subgroup analysis of outcome according to macular hole size, all holes smaller than 400 μm closed regardless of posturing (100%). In contrast, holes larger than 400 μm closed in 10 of 11 eyes (91% 95% CI 58–99%) in the posturing group and in only 4 of 10 eyes (40% 95% CI 12–74%) in the non-posturing group (Fisher''s exact test P=0.02).

Conclusion

Post-operative face-down positioning may improve the likelihood of macular hole closure, particularly for holes larger than 400 μm. These results support the case for a RCT.     

Visual outcome in Japanese patients with Acanthamoeba keratitis

Purpose

To identify prognostic factors affecting visual outcome in Acanthamoeba keratitis (AK) treated with topical chlorhexidine gluconate (CHG).

Methods

A total of 35 eyes in 34 patients with AK were treated with 0.02% topical CHG. Patients were divided into two groups according to the final visual outcome: Group 1, final visual acuity (VA) of 20/25 or greater (22 eyes); Group 2, less than 20/25 (13 eyes). We compared these groups and evaluated the effectiveness of topical CHG compared with outcomes in previous reports.

Results

Ring infiltrate was observed more often in Group 2 (4.5% vs 61.5%, OR 33.6, 95% confidence interval (CI) 3.4–333.9, P<0.01). The duration between onset and diagnosis of AK was significantly longer (24.9 days vs 48.4 days, OR 1.03, 95% CI 1.00–1.06, P=0.04) and VA at initial examination (log MAR) significantly lower (0.47 vs 1.59, OR 25.5, 95% CI 3.4–186.7, P<0.01) in Group 2 (visual outcome <20/25). Multivariate analysis revealed that only VA at initial examination was independently associated with worse visual outcome (adjusted OR 24.5, 95% CI 1.9–312.6, P=0.01). Seventeen (85.0%) of the 20 eyes diagnosed within 1 month and 24 (82.8%) of 29 eyes diagnosed within 2 months achieved a VA of 20/40 or greater.

Conclusion

VA at initial examination was the most predictive factors for final visual outcome in AK. Topical CHG was comparably effective to other treatments, including polyhexamethyl biguanide and propamidine isethionate.     

The incidence and distribution of iatrogenic retinal tears in 20-gauge and 23-gauge vitrectomy

Purpose

The development of 23-gauge vitrectomy surgery has many benefits including a reduction in surgical time and faster postoperative rehabilitation; however, some have suggested that the complication rate is higher. To assess this we compared the incidence and distribution of iatrogenic retinal tears in 20- and 23-gauge surgery.

Methods

Fifty consecutive 23-gauge and 50 consecutive 20-gauge vitrectomy cases were selected; eyes with a history of previous vitreoretinal surgery were excluded. All surgery was performed by two surgeons (JL and RN). Entry-site breaks (ESB) were defined as any new vitreoretinal abnormality occurring within 1 clock hour of an entry site for which treatment with cryotherapy was deemed necessary. Data were collected by retrospective case note review. Statistical analysis was carried out using Fisher''s exact and χ²-tests.

Results

ESB occurred in 24% (12/50) of cases in the 20-gauge group compared with 8% (4/50) in the 23-gauge group (P=0.03); 88% (14/16) occurred superiorly on the same side as the surgeons'' dominant hand. Iatrogenic breaks recorded elsewhere indicated an increased incidence in the 20-gauge group (9/50 compared with 6/50 in 23-gauge) but this did not achieve significance; the most common position was at 6 o''clock.

Conclusions

23-Gauge vitrectomy is associated with significantly fewer ESB when compared with conventional 20-gauge vitrectomy. The incidence of other iatrogenic breaks did not appear to be significantly different between the two groups.     

Visual and anatomical outcomes following vitrectomy for complications of diabetic retinopathy: the DRIVE UK study

Introduction

End-stage diabetic eye disease is an important cause of severe visual impairment in the working-age group. With the increasing availability of refined surgical techniques as well as the early diagnosis of disease because of screening, one would predict that the prevalence of this condition is decreasing and the visual outcome is improving.

Aim

To study the prevalence and visual outcome following vitrectomy for complications of diabetic retinopathy.

Materials and methods

This study identified the patients who underwent vitrectomy from January 2007 to December 2009 because of diabetes-related complications in South East London. Data collected included baseline demographics, best-corrected visual acuity, indication for the vitrectomy, complication, outcome, and duration of follow-up.

Results

The prevalence of people requiring vitrectomy who are registered in the diabetes register of this region was 2 per 1000 people with diabetes. Vitrectomy was required in 185 eyes of 158 patients during this period. These included 83 Caucasians, 51 Afro-Caribbeans, 17 South Asians, and 7 from other ethnic groups. There were 58 patients with type I diabetes and 100 with type II, with a mean duration of diabetes of 23 and 16.5 years, respectively. The reason for vitrectomy included tractional retinal detachment (TRD) in 109 eyes, non-clearing vitreous haemorrhage (NCVH) in 68 eyes, and other causes in 8 eyes. In all, 50% of the eyes with TRD and NCVH, and 87% of the eyes with NCVH improved by at least three ETDRS lines at 12 months. Poor predictors of visual success included longer duration of diabetes (OR: 0.69), use of insulin (OR: 0.04), presence of ischaemic heart disease (OR: 0.04), delay in surgery (OR: 0.59), and the failure to attend clinic appointments (OR: 0.58). Preoperative use of intravitreal bevacizumab in eyes with TRD undergoing vitrectomy showed a marginal beneficial effect on co-existent maculopathy (P=0.08) and required less laser intervention post procedure, but did not affect the number of episodes of late-onset vitreous haemorrhage post vitrectomy (P=0.81).

Conclusion

Visual outcome has improved significantly in eyes with complications due to diabetic retinopathy compared with the previously reported Diabetic Vitrectomy Study.     

Acute retinal necrosis: factors associated with anatomic and visual outcomes

Purpose

To examine the factors associated with anatomic and visual outcomes in Japanese patients with acute retinal necrosis (ARN).

Methods

One hundred four patients with ARN who were followed for more than 1 year at nine referral centers were reviewed. Retinal involvement at initial presentation was classified into four groups: zone 1 (posterior pole, n = 22), zone 2 (midperiphery, n = 54), zone 3 (periphery, n = 25), and unknown (n = 3). Forty-eight eyes underwent prophylactic vitrectomy before development of retinal detachment (vitrectomy group); 56 eyes were treated conventionally without prophylactic vitrectomy (observation group).

Results

The retina was attached in 28 of 48 eyes (58.3 %) in the vitrectomy group and 42 of 56 eyes (75.0 %) in the observation group at the final visit (P = 0.071). At 1 year, 56 eyes (53.8 %) had a best-corrected visual acuity (BCVA) of 20/200 or worse. Multivariate logistic regression analyses identified zone 1 disease (odds ratio = 4.983) and optic nerve involvement (odds ratio = 5.084) as significantly associated with BCVA of 20/200 or worse. Among the zone 3 eyes, significantly (P = 0.012) more eyes in the observation group than in the vitrectomy group had an attached retina.

Conclusions

Prophylactic vitrectomy did not improve the final BCVA in any eyes. Zone 3 eyes had better outcomes without prophylactic vitrectomy.