Hyperbaric oxygen therapy for perioperative posterior ischemic optic neuropathy: a case report.

PURPOSE: To report the successful treatment of postoperative posterior ischemic optic neuropathy (PION) with hyperbaric oxygen therapy and to review the current literature on the pathogenesis and treatment of PION. OBSERVATIONS: During an angiographic procedure at a community hospital, an elderly woman had a transient drop in blood pressure after receiving an intravenous dose of hydralazine. During recovery, the patient experienced bilateral vision loss. She was transferred to our specialty referral center for treatment with hyperbaric oxygen. We followed Table 5 in the U.S. Navy Diving Manual, the protocol for decompression sickness. Our patient's vision improved markedly immediately after the first session and continued to improve throughout the course of treatment to its completion. Follow-up ophthalmology visits found the patient's vision to be close to baseline. CONCLUSIONS AND IMPORTANCE: PION is a rare condition. It has been difficult to determine a successful therapeutic approach because of the lack of large case-controlled studies. Hyperbaric oxygen has been used to treat other ischemic ophthalmic conditions, but there are only few reports of its use in patients with PION. Systemic steroids and antiplatelet therapy have also been used, with mixed success. In our patient, the combination of hyperbaric oxygen therapy and steroids was successful in restoring vision after postoperative PION.

[Study on electroacupuncture along the visual conductive pathway for ocular cell apoptosis in anterior ischemic optic neuropathy].

OBJECTIVE: To study the protective effect of electroacupuncture (EA) along the visual conductive pathway for the optic nerve tissue of anterior ischemic optic neuropathy (AION) in terms of the structure and apoptosis. METHODS: The AION model of right eye was established with laser in 48 New Zealand white ear rabbits. All rabbits were randomly divided into a model group, an acupuncture group and an acupuncture combined with EA group, 16 rabbits in each one. Other 16 normal left eyes were selected as a blank group. Acupuncture and EA of 30 min were used in the corresponding groups for 3 days at the right "Cuanzhu" (BL 2), "Yuyao" (EX-HN 4) and "Qiaomingxue" (Extra), once a day. There was no intervention in the model group and the blank group. The morphological structure and retinal thickness of lining of the optic nerve were detected with HE stain. The expressions of the Bcl-2 and Bax in the retina were detected with immunohistochemistry. And the concentration of tumor necrosis factor-α (TNF-α) in the retina was detected with enzyme linked immunosorbent assay (ELISA). RESULTS: In the model group, the ganglion cell layer revealed hyperplasia and disorder, and the retina ganglion cells revealed loose arrangements, thin inner nuclear layers, and reduction of cell amounts, some long parts missing cells. However, the above structural damages were much weaker in the acupuncture group and acupuncture combined with EA group. The inner layer of the retina in the model group was thinner than that in the blank group (P<0.05). That in the acupuncture combined with EA group showed significant better results than those in the acupuncture and model groups (both P<0.05), which was not statistically different from that in the normal group (P>0.05). The Bcl-2 count in the model group was lower than that in the blank group (P<0.05), and that in the acupuncture combined with EA group was better than those in the acupuncture and model groups (both P<0.05), not significantly different from that in the blank group (P>0.05). The number of Bax in the model group was higher than that in the blank group (P<0.05), and that in the acupuncture combined with EA group was lower than those in the acupuncture and model groups (both P<0.05), and was similar to that in the blank group (P>0.05). Bcl-2/Bax in the model group was lower than that in the blank group (P<0.05). The value in the acupuncture combined with EA group presented better than those in the acupuncture and model groups (both P<0.05), which had no difference from that in the blank group (P>0.05). TNF-α in the model group was higher than that in the blank group (P<0.05), and no such differences were detected between other groups and the model group (bothP>0.05). CONCLUSIONS: EA along the visual conductive pathway is protective to some extent for optic nerve tissue, which can increase the expression of Bcl-2 and reduce the expression of Bax so as to restrain ganglion cell apoptosis.

Bilateral non-arteritic ischemic optic neuropathy treated with HBO2 therapy: A case report of angiographic and electrodiagnostic findings.

INTRODUCTION: Non-arteritic anterior ischemic optic neuropathy (NAION) is one of the most widespread visually disabling diseases in the middle-aged and elderly population. It typically presents as acute painless unilateral vision loss in patients over 50 years of age. The fellow eye of NAION patients is often sequentially affected. Involvement of the second eye occurs within three years in approximately 45%-50% of patients. Currently there is no generally accepted treatment for NAION but a number of medical and surgical therapies have been proposed. REPORT OF A CASE: This is a case of non-contemporary bilateral non-arteritic anterior ischemic optic neuropathy (NAION) in a 66-year old woman treated with hyperbaric oxygen (HBO2) therapy after ineffective systemic corticosteroid therapy. Visual acuity (VA), visual evoked potentials (VEP) findings, perimetric examination results and angiographic images were recorded and analyzed before and after hyperbaric oxygen treatment. DISCUSSION: After several months from the optic nerve vascular injury, VA, VEP values, perimetric examination results and angiographic images revealed a very important recovery. These results maintained stable during the follow-up at about nine months. HBO2 therapy has been revealed to be a safe and efficacious adjunctive therapy, even after many months after the injury. While this case is promising, double-blind randomized controlled trials will be necessary to prove the efficacy of HBO2 in the treatment of NAION.

Reduction of apoptosis in ischemic retinas of two mouse models using hyperbaric oxygen treatment.

PURPOSE: To investigate the effect of hyperbaric oxygen (HBO) chamber treatment in mouse models of retinal ischemia. METHODS: Unilateral central retinal artery occlusion (CRAO) or optic nerve crush (ONC) was induced in 50 mice each, of which 30 were treated with 100% oxygen at 2 atm for 90 minutes immediately after injury and then daily for up to 14 days. Mice were euthanatized on days 1, 3, and 21 for histologic analysis, apoptosis assay, and quantitative real-time polymerase chain reaction test. Findings were analyzed by injury and by treatment. RESULTS: HBO treatment reduced cell loss from 58% to 30% in the CRAO model and from 52% to 32% in the ONC model. In both models, it was associated with significantly increased cell survival in the retinal ganglion cell layer. Expression levels of the proapoptosis genes (bax, caspase-3) decreased minimally in the HBO-treated CRAO mice on day 1, but this trend was reversed on day 3. In the ONC group, levels of caspase-3, bax, and bcl-x increased on day 1 and dropped below baseline on day 3. The pattern of changes in the expression levels of the ischemia- and oxidative-stress-related genes (HO-1, SOD-1, GPX-1, NOX-2) and the effectiveness of HBO treatment varied by model. Overall, however, gene expression levels that increased in the untreated mice increased further with HBO treatment and levels that decreased, decreased further with treatment. CONCLUSIONS: HBO treatment protects injured neuronal cells from apoptosis. Response to treatment differs molecularly after ONC or CRAO. These results should prompt clinical trials of acute ischemic retinal damage.

Effect of transcorneal electrical stimulation in patients with nonarteritic ischemic optic neuropathy or traumatic optic neuropathy.

PURPOSE: To determine whether transcorneal electrical stimulation (TES) can improve the visual function of patients with nonarteritic ischemic optic neuropathy (NAION) or traumatic optic neuropathy (TON). METHODS: Eight consecutive patients at the Osaka University Hospital were studied. TES (600-800 microA, 20 Hz, 30 min) was applied once each to three eyes with NAION and to five eyes with TON, using a contact lens-type stimulating electrode. The primary outcome measurement was the change in visual acuity at 1 to 3 months after TES. An improvement in visual acuity was defined as a change of > or =0.3 log (minimum angle of resolution) (logMAR) units. The side effects of TES were also investigated. RESULTS: After TES application, the visual acuity improved in two patients with NAION and in four patients with TON. Visual acuity did not worsen in any of the eyes. Only a mild superficial punctuate keratopathy was observed in all eyes immediately after TES, and it healed by the next day. CONCLUSIONS: Visual acuity can be improved after TES without major complications in some patients with NAION or TON. These results suggest that TES should be considered as a new treatment for eyes with optic neuropathy.

Treatment of ischemic optic neuropathy.

Ischemic damage of the optic nerve has no proven effective treatment. While ischemia related to vasculitis (arteritic) is treated with systemic corticosteroids, the primary goal is to prevent further damage, either in the affected or fellow eye. Thrombolytic or anticoagulation supplementive therapy may be considerations for the future. In the more common idiopathic (nonarteritic) form (NAION), multiple attempts at therapy, including systemic corticosteroids, anticoagulants and antiplatelet agents, diphenylhydantoin, hyperbaric oxygen, and optic nerve sheath decompression have been unsuccessful. The use of levodopa has been proposed but is unproven. Megadose intravenous corticosteroid therapy has not been studied in a systematic way. Neuroprotective strategies are under intense investigation for optic neuropathies including NAION, and clinical trials in humans are in progress. Optic nerve regeneration studies are ongoing in animals. Prophylaxis in NAION is unproven.

Hyperbaric oxygen therapy in two patients with non-arteritic anterior optic neuropathy who did not respond to prednisone.

Recent advances in understanding the effects of hyperbaric oxygen (HBO) on retinal anoxia gave rise to new interest in the possibility of using it as therapeutic treatment for ischemic conditions of the retina and optic nerve. Two patients with non-arteritic anterior ischemic optic neuropathy due to a high-grade ophthalmic artery stenosis were treated with HBO at 2 atm abs in an effort to increase oxygen delivery for the eye. Both patients showed marked improvements of visual acuity and visual field 3-5 months following the event. Our results are intriguing although the achieved improvement could be coincidental.

Bilateral simultaneous optic nerve dysfunction after periorbital trauma: recovery of vision in association with with chiropractic spinal manipulation therapy.

OBJECTIVE: To discuss the recovery of optic nerve function after chiropractic spinal manipulation in a patient with loss of vision as a result of facial fracture from a fall. CLINICAL FEATURES: In a fall down a stairwell, a 53-year-old woman with migraines fractured her right zygomatic arch, which was later treated surgically. Approximately 3 weeks after the accident, vision in her contralateral eye became reduced to light perception. Electrophysiologic studies revealed that the function of both optic nerves was diminished, the right significantly more than the left. Single photon emission tomography showed pancerebral ischemic foci. INTERVENTION AND OUTCOME: Chiropractic spinal manipulation was used to aid recovery of vision to normal over a course of 20 treatment sessions. At times, significant improvement in vision occurred immediately after spinal manipulation. Progressive recovery of vision was monitored by serial visual field tests and by electrophysiologic studies. Unfortunately, the patient refused a further single photon emission tomographic study when visual recovery was complete. CONCLUSION: This case report adds to previous accounts of progressive and expeditious recovery of optic nerve function in association with spinal manipulation therapy.

Hyperbaric oxygen therapy for nonarteritic anterior ischemic optic neuropathy.

PURPOSE: To evaluate the effectiveness of hyperbaric oxygen therapy in reducing optic nerve damage in acute nonarteritic anterior ischemic optic neuropathy. METHODS: Twenty-two eyes in 20 patients with acute nonarteritic anterior ischemic optic neuropathy were treated with hyperbaric oxygen (100% oxygen, 2.0 absolute atmospheres of pressure) in two 90-minute inhalation sessions per day for ten days. Changes in mean visual acuity and mean sensitivity loss were compared with those of 27 untreated control patients with acute nonarteritic anterior ischemic optic neuropathy, and proportions of patients with a change in acuity or mean sensitivity loss were compared with controls. Similar analysis was performed on subgroups based on time delay from symptom onset to therapy. RESULTS: Mean values for visual acuity were increased at final examination in both groups; although the increase was greater in controls, the difference was not statistically significant. Mean visual field sensitivity loss was minimally increased; although the increase was smaller in controls, the difference between groups was not significant. There was no significant difference between groups in proportions of patients with change in acuity score or mean sensitivity loss. Stratification by time delay to therapy did not suggest that treatment within nine days produced better visual results than that for either controls or those treated later. CONCLUSIONS: Hyperbaric oxygen therapy using 100% oxygen and 2.0 absolute atmospheres of pressure did not produce a significant improvement in visual acuity or visual field for patients with acute nonarteritic anterior ischemic optic neuropathy.

Hyperbaric oxygen for the treatment of nonarteritic anterior ischemic optic neuropathy.

This clinical study tackled the problem of hyperbaric oxygen in patients with nonarteritic anterior ischemic optic neuropathy. Twenty-one patients were included in the study. The patients were divided into two groups: experimental and control. Experimental group consisted of 10 patients, who had been previously treated with corticosteroids, without significant success. In four patients with a clinical picture of PNO atrophy, medical steroid treatment failed to any significant improvement in visual acuity. In 6 patients, however, this treatment resulted in a significant improvement of both visual acuity and field of vision. These patients showed further improvement on control testing performed six month later. All patients from the control group were treated with corticosteroids per os and by local application, but without any significant improvement as revealed by visual acuity and visual field testing. Authors' results pointed the possibility of conservative treatment of patients with anterior ischemic optic neuropathy, especially those in whom steroid therapy had proved inefficient.