Macular hole surgery-associated peripheral visual field loss

Incomplete fluid-air exchange technique for idiopathic macular hole surgery

AIM

To explore an improved procedure involving incomplete fluid-air exchange for idiopathic macular hole (IMH), and the closure rate, visual function, and the visual field of macular holes (MHs) were evaluated.

METHODS

This prospective randomized controlled study, included 40 eyes of 40 patients with IMH who were treated with pars plana vitrectomy and peeling of the internal limiting membrane. They were grouped by random digital table. Twenty-one eyes underwent incomplete fluid-air exchange (IFA) and 19 eyes underwent traditional complete fluid-air exchange (CFA) as the control group. Outcomes included best-corrected visual acuity (BCVA), intraocular pressure, and optical coherence tomography, light adaptive electroretinography, and visual field evaluations.

RESULTS

All MHs <400 µm were successfully closed. BCVAs before and 6mo after surgery were 0.82±0.41 logMAR and 0.28±0.17 logMAR in IFA group and 0.86±0.34 logMAR and 0.34±0.23 logMAR in CFA group, respectively. The electroretinogram analysis of patients in IFA group revealed increases in b-wave amplitudes at 1, 3, and 6mo after surgery. Additionally, patients in IFA group showed an amplitude increase of 28.6% from baseline at 6mo (P<0.05), while no obvious improvements were noted in CFA group. Although there were no statistically significant improvements in either group, the IFA group showed a slight increase in mean sensitivity (P>0.05).

CONCLUSION

IFA is a reliable method that offers comparable closure rate to CFA and facilitates improvements in visual function.

Scleral Buckling versus Vitrectomy for Retinal Detachment Repair: Comparison of Visual Fields and Nerve Fiber Layer Thickness

PURPOSE

To compare visual field loss and retinal nerve fiber layer (RNFL) defects in cases of rhegmatogenous retinal detachment (RRD) treated with scleral buckle (SB) versus pars plana vitrectomy (PPV) and C3F8 injection.

METHODS

This was a prospective, comparative interventional study of 50 eyes with primary RRD, treated with PPV (25 eyes) or SB (25 eyes). All measurements took place at least 9 months following successful and uncomplicated surgical treatment. The visual field total deviation (TD) values for preoperative attached and detached areas were calculated and compared separately. The optic nerve head morphology was studied with Heidelberg retinal tomography (HRT), and the RNFL using spectral-domain optical coherence tomography.

RESULTS

The preoperative detached areas demonstrated more affected TD values (in dB) compared to the preoperative attached areas (-6.9 ± 5.2 vs. -4.3 ± 3.3 for the SB group and -9.6 ± 5.2 vs. -7.8 ± 5.1 for the PPV group; p = 0.001) in both groups. The preoperative attached areas of the SB group showed better TD values (calculated mean values) compared to the preoperative attached areas of the PPV group (-4.3 ± 3.3 vs. -7.8 ± 5.1, p = 0.007). The RNFL and HRT values showed no statistically significant difference between the two groups.

CONCLUSIONS

It seems that the preoperative detached retina, despite successful reattachment, suffers permanent damage as a result of the detachment, irrespective of the method of treatment. In the PPV group, the postoperative functionality of the preoperative attached areas was detected to be worse compared to the postoperative functionality of the preoperative attached areas of the SB group. We postulate that this fact could be attributed to an additional traumatizing factor (possibly fluid-air exchange or gas injection) in patients with RRD treated with PPV.

Long-term intraocular pressure changes after combined phacoemulsification, intraocular lens implantation, and vitrectomy

PURPOSE

To observe long-term changes in intraocular pressure (IOP) after a combined phacoemulsification, intraocular lens implantation, and vitrectomy procedure.

METHODS

This was a retrospective case series at a single hospital. Of 105 consecutive cases that received combined phacoemulsification, intraocular lens implantation, and vitrectomy for macular hole or epiretinal membrane, 85 eyes (patients) were followed up for 1 year or longer. The IOP of both eyes in the subjects who had surgery in one eye was measured at baseline and at 1, 3, 6, 12, 24, 36, 48, and 60 months postoperatively. The IOP of the treated eye was compared with the fellow eye and with the baseline value at each follow-up visit.

RESULTS

Intraocular pressure in the operated eyes at 3 months after surgery was significantly lower than that at baseline and than that in the respectively fellow eyes (P < 0.001, paired-t test with Bonferroni correction). The IOP subsequently returned to the baseline value or was the same as that of the fellow eye within 3 months of the observation time point. Only two treated eyes had elevated IOP exceeding 21 mmHg after 6 months postoperatively.

CONCLUSIONS

The change in the IOP after phacovitrectomy may be limited, and care when using this procedure because some eyes show increased IOP compared to the fellow eye after a long period.

Vital staining with indocyanine green: a review of the clinical and experimental studies relating to safety

Indocyanine green (ICG) is extremely effective when used as a vital stain during macular hole surgery. By staining the internal limiting membrane, ICG facilitates removal of this delicate and sometimes hard to visualize structure. There is, however, considerable debate regarding its safety. This review considers the clinical and experimental studies of ICG and a related agent, infracyanine green. Some clinical papers show visual field defects, reduced visual acuity, and persistence of ICG at the macula and optic nerve. Other clinical studies fail to demonstrate toxicity. The experimental studies are also conflicting, but there are emerging trends. These suggest that surgeons who continue to use ICG should use concentrations not greater than 0.05 mg/ml, in fluid-filled eyes, with short exposure times, iso-osmolar solutions, and avoid proximal or prolonged endoillumination of stained tissue. A smaller number of studies suggest that infracyanine green produces similar staining to ICG, and may possibly be safer, but there are too few well-designed studies to reach a conclusion. Although the use of ICG continues, on the balance of evidence, this review suggests that it is has the potential to produce subtle visual damage.

Central and Paracentral Visual Field Defects and Driving Abilities

The effect of central and paracentral visual field defects on driving abilities has until now received little attention. To date studies and surveys have concentrated on visual acuity and peripheral field loss. Here we summarise for the first time those diseases causing central visual field defects likely to be associated with binocular visual acuity adequate for driving.

Nonarteritic anterior ischemic optic neuropathy and ‘visual field defects’ following vitrectomy: could they be related?

BACKGROUND

Visual field defects after uncomplicated vitrectomy have been reported but poorly explained. We describe two cases of nonarteritic anterior ischemic optic neuropathy (NAION) observed following vitrectomy. We also reviewed the literature for cases of post-vitrectomy visual field defects for evidence of optic nerve damage.

METHODS

Two patients developed optic disc edema and features of an optic neuropathy after uncomplicated vitrectomy for macular hole and epiretinal membrane. A systematic literature search was conducted to obtain prior reports of visual field defects or ischemic optic neuropathy following vitrectomy. Additional studies were identified from the bibliographies of the retrieved articles.

RESULTS

The incidence of visual field defects following vitrectomy has varied from 1-71% across all studies. Overall, we found 160 (14.5%) cases of unexplained visual field defects following vitrectomy out of 1,104 patients. Of these, 31 eyes (19.4%) have shown some sign of optic nerve damage following vitrectomy, including pallor in 29 eyes, relative afferent pupillary defect in eight eyes, and intrapapillary hemorrhage in two eyes.

CONCLUSIONS

NAION may develop following vitrectomy. "Visual field defects" following vitrectomy are common and many of the involved eyes demonstrate evidence of optic nerve damage, some of which may have represented NAION.

VISUAL FIELD DEFECTS AFTER RADIAL OPTIC NEUROTOMY FOR CENTRAL RETINAL VEIN OCCLUSION

PURPOSE

Surgical decompression of the vein in central retinal vein occlusion (CRVO) by radial optic neurotomy (RON) was recently proposed as being surgically feasible, safe, and beneficial. The effect of RON on the visual field has not been systematically reported, although possible visual field defects are expected due to iatrogenic cutting of the optic nerve fibers. The authors report the results of visual field testing in patients who underwent RON at the Tel Aviv Medical Center.

METHODS

Twelve consecutive patients (8 men, mean age of all patients 68 years) with nonperfused or indeterminate CRVO whose initial visual acuity (VA) was < or =20/400 underwent RON. Nine of these patients were able to perform visual field tests at 6 months post-RON and their visual field results are presented.

RESULTS

: VA improved by > or =3 lines in 5 patients (42%). Three (25%) patients had a final VA of > or =20/200 and another had a final VA > or =20/50. Fundus and VA improvement were relatively slow. Two patients had clearing of the intraretinal blood, resolution of the venous dilation, and improved VA at the 2-month follow-up visit. Temporal visual field defects consisting of temporal ones that could be correlated to the site of the RON incision were detected in five out of the nine patients who were able to perform visual field tests. No temporal visual field defects were found in the remaining four patients, and three other patients were unable to perform visual field tests due to inability to identify the largest target size.

CONCLUSION

VA improvement in 5 of 12 patients with ischemic or indeterminate CRVO following RON may be better than the natural history of CRVO. The risk of visual field defects may, however, be heightened by possibly cutting off blood supply to the optic nerve head and possible damage to nerve fibers in the optic nerve head, both inherent to the surgical procedure and both likely to produce visual loss.

Visual field defects after uneventful vitrectomy for epiretinal membrane with indocyanine green-assisted internal limiting membrane peeling

PURPOSE

To report visual field defects after vitrectomy for epiretinal membrane with indocyanine green (ICG)-assisted internal limiting membrane (ILM) peeling.

DESIGN

Interventional consecutive case series.

METHODS

A retrospective review of 16 eyes of 16 patients who underwent vitrectomy for idiopathic epiretinal membrane. Indocyanine green-assisted ILM peeling was performed in 7 of 16 eyes. The main outcome measure was postoperative visual field.

RESULTS

Four of seven eyes (57%) with ICG-assisted ILM peeling had visual field defects postoperatively. The field defects identified were nasal in three eyes; in the fourth eye, the visual field was constricted to approximately 30 degrees. None of the nine eyes without ICG-assisted ILM peeling had a visual field defect.

CONCLUSIONS

Peripheral visual field defects may occur after vitrectomy with ICG-assisted ILM peeling. Although the cause of the defects is unclear, the potential role of ICG toxicity requires further investigation.