Systematic Management Approach for Children and Adolescents With Orbital Lymphatic Malformation

This is an interventional study aiming at setting systematic approach for children and adolescents with orbital lymphatic malformation and to assess the safety and efficacy of sirolimus in patients with orbital lymphatic malformation Patients with lymphatic malformation will be subdivided according 4 grades, grade1 the size of the cyst, grade 2 the extension , grade 3 the angiogensis , grade 4 according to symptoms Grade 1:According to the size of cyst, Lymphatic malformation are divided into macrocystic (>2cm), microcystic(<2cm) and mixed cyst.Grade 2: According to the extension , lymphatic malformation are divided into superficial (presenting as a subcutaneous cyst); deep (having orbital infiltration);combined (superficial and deep components); complex (intracranial or head and neck infiltration) (10).

Grade 3: According to angiogensis, lymphatic malformation are divided into simple lympahtic malformation or combined with venous element or capillary malformation Grade 4 : According to symptoms , lymphatic malformation are divided into asympyomatic and symptomatic Patients will be assigned to available treatment modality either local control via injection sclerotherapy or surgery verus sirolimus orally either alone or combined with local control.

Group 1: All Patients with symptomatic lymphatic malformation except those with complex lymphatic malformation.They will be assigned to sclerotherpay .Local intralesional trancutaneous injection dose will be 0.6 mg / kg of bleomycin dissolved in the total volume of the lesion calculated from dimensions of orbital lesion in MRI orbit with contrast. Intralesional injection frequency will be guided by clinical response of the patients and imaging studies.If there is response clinically, injection will be continued every one month until there is no further response or if the lesion is reaching 75% of lesion size Or if there is no response from first injection.For lid and conjunctival components local injection will be for small , moderate and large lesions 2 IU, 4 IU, 6 IU respectively and further injection every month guided by lesion response.Less than 25% reduction will not receive further injection, if there is 25%- 50 % reduction injection will continue till reaching 75% or more clinical reduction in size (9) Group 2: Patients assigned to sirolimus arm will be patients with A) Patients with symptomatic complex lymphatic malformation. B) Patients in group 1 if there is progression in lesion size or ineffective local therapy.

Group 3 :Patients assigned to both modality from the start :

A) Patients in group 1 or complex if there is concern for complications like hemorrhage, amblyopia and vision loss since diagnosis.