The Complexities of Orbital Arteriovenous Malformations: A Systematic Review of Clinical Features and Treatment Approaches.

The orbital vascular malformations are very rare congenital lesions characterized by a connection directly between arteries and veins, thus bypassing the capillary network. These lesions may be associated with clinical features ranging from mild proptosis to vision-threatening conditions like visual loss and elevated intraocular pressure. Despite advances in imaging and treatment strategies, the management of orbital arteriovenous malformations (AVMs) still remains daunting because of the high risk of complications, including hemorrhage and incomplete resection. This systematic review was done according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A detailed search of the major databases such as PubMed and Scopus was performed using the keywords "Ocular OR orbit AND arteriovenous malformations OR AVM" without specifying the date. All case reports, case series, and observational studies reporting the diagnosis, treatment, and outcome of patients with orbital AVM were included. Data extraction was focused on clinical presentations, diagnostic modalities, treatment interventions, and outcomes; narrative synthesis was done due to heterogeneity in the studies. This review contains 27 case reports, where the number of patients ranged between three years and 75 years with a mean age of 34 years. The majority of the patients were males constituting 66%. The common clinical features include proptosis in 16 cases, visual loss in 12 cases, and chemosis in seven cases. Most of the patients underwent surgical resection and embolization of the malformations. In most of the cases, surgical resection was uneventful; however, a few cases with high risks showed hemorrhage and loss of vision as complications. Conservative management was also effective in certain stable or asymptomatic cases. Orbital vascular malformations include complex diagnostic and therapeutic challenges due to the complex anatomy of the orbit and the high risk of serious complications. This systematic review aimed at presenting the clinical features, diagnostic challenges, and treatment outcomes of orbital arteriovenous malformations for a better management strategy. Further research is required in the refinement of treatment protocols, especially regarding high-flow lesions, and a critical look at improving long-term efficacy.