Title : Hyperbaric oxygen therapy for crao in a pediatric patient: A case of sudden unilateral visual loss Post-DSA of an arteriovenous malformation
Abstract:
Central retinal artery occlusion (CRAO) is an ophthalmic emergency that typically presents as a sudden, profound, and painless monocular visual loss, potentially leading to permanent blindness. While rare in the pediatric population, the etiology in children can differ from that of the elderly. Causes are often multifactorial but mostly non-arteritic in origin such as embolism, hypercoagulable states, trauma, and vascular diseases like Moyamoya disease and Fabry disease. Despite the variety of proposed pharmacological and surgical treatments, their effectiveness remains limited and inconclusive. We present the case of a young girl with a left mandibular arteriovenous malformation (AVM) who suffered unilateral vision loss following treatment with digital subtraction angiography (DSA).
This 8-year-old patient has a left mandibular AVM complicated by hemorrhagic bleeding, which required resuscitation and treatment with DSA on two occasions within six months. She presented to the ED with recurrent AVM bleeding. Despite no acute changes on MRA, DSA was performed to assess active bleeding. During the procedure, bleeding in the AVM region was noted, prompting re-embolization. However, upon arrival at the ward, the patient reported decreased vision in her left eye. Examination confirmed reduced visual acuity. A multidisciplinary team, including Endovascular Neurosurgery, Ophthalmology, Neurology, and Hematology, evaluated the patient. Aspirin and methylprednisolone were administered to address potential embolism and edema, respectively. Moreover, MRI of the head and orbits revealed post-DSA changes without evidence of acute ischemia, hemorrhage, or edema.
Dilated fundus examination revealed clear media, a cup-to-disc ratio of 0.3, a pink optic nerve without swelling, attenuated arteries, dilated veins, and a pale retina, confirming a diagnosis of CRAO in the left eye. The choroidal circulation was also affected, as no cherry-red spot was observed. A macular optical coherence tomography revealed significant hyperreflectivity and thickening of the inner retinal layers consistent with the edema typically seen in acute retinal artery occlusions. Intravenous fluorescein angiography showed delayed retinal artery filling, arteriovenous phase, and patches of delayed choroidal filling. Based on previous adult cases showing some improvement with hyperbaric oxygen therapy (HBOT), the hyperbaric service was consulted in an effort to reduce edema, improve retinal blood flow, and preserve the tissue adjacent to the ischemic area. After initial sessions, the patient showed mild improvement, being able to count fingers at 1–2 feet, whereas initially, she could only detect hand movements.
CRAO is a serious ocular emergency that is rarely seen in the pediatric population but requires prompt evaluation and intervention to potentially prevent permanent blindness. Since the retina has a high oxygen demand, placing patients in a hyperoxic state may offer some improvement. Although hyperbaric chambers have not been well studied in pediatric patients, our patient received this therapy in the hopes of improving her visual function and quality of life. This case underscores the urgency of prompt diagnosis and treatment of CRAO, the need for further research into pediatric therapies that yield consistent clinical responses, and the importance of a multidisciplinary approach when managing such complex cases.
