The fate of patient suffering from Endocrine Orbitopathy (EO) is not an easy one. The ophthalmic manifestations may range from mild eye discomfort to severe impairment of vision caused by eyelid retraction, proptosis and corneal exposure, restrictive myopathy or compressive neuropathy.
A number of medical therapeutic options exist, including corticosteroids, immunotherapy and, in very selected cases, radiotherapy.
But often, despite correct medical management, ocular manifestations persist. Thus there is indication for surgery.The complexity of the disease thus requires a well organized TEAM APPROACH and treatment.This means that the patient affected by EO must be evaluated by different specialists in order to suggest proper diagnosis and treatment.
Therefore the Team should include: Endocrinologist, Ophthalmologist, Neuroradiologist, Anaesthetist, Surgeon, the Radiotherapist.A Team, of all the above mentioned specialists, has been set up at Hospital-University of Ferrara since more than 4 years. It is only from the close collaboration among the Team members that a patient suffering from EO is able to receive proper study and treatment.
(Ref. Rationale of Treatment in Graves Ophthalmopathy: L. Clauser, M. Galiè, E. Sarti, V. Dallera – Plast. Reconstr. Surg. 108,2001)
STUDY AND TREATMENT OF ENDOCRINE ORBITOPATHY (GRAVES’ DISEASE)
TEAM
Maxillo Facial Surgeon
Endocrinologist
Ophthalmologist
Neuroradiologist
Anesthetist
Neurologist
Endocrine Orbipathy (E.O.) is a chronic disease caused by an autoimmune process, characterized by the presence of antibodies which stimulate a general fibroblastic reaction (thyroid gland and lower extremities) and involves the extraocular muscles, the intra and extraconal fat. The lacrimal gland can be involved as well. E.O. may either be associated with toxic diffuse goitre and/or pretibial mixoedema (Graves’ disease). It may appear alone in absence of any apparent thyroid dysfunction (euthyroidism).
The importance of co-operation among a team of specialists including endocrinologist, ophthalmologist, neuroradiologist, surgeon, anaesthetist, radiotherapist is of paramount importance in the management of this complex disease.
The histopathological changes which occur in ophthalmopathy allows to identify two forms defined as type 1, characterized by stimulation of retrobulbar fat and connective tissue, and type 2, characterized by extraocular myositis with oedema and lymphocyte infiltration and increased muscular thickness.
E.O. is more frequent in women, with a 1:5 male-female ratio, with a peak incidence occurring in the third and fourth decades.There is an increased prevalence in smokers (perhaps due to the decreased immunosuppression which allows greater expression of autoimmune processes) , and a genetic predisposition as well.
Exophthalmos is found in 40% of patients with Graves’ disease. Eighty percent of these subjects are clinically hyperthyroid and 20% are clinically euthyroid. The degree of exophthalmos is not always related to the severity of thyrotoxicosis, and paradoxically,may appear after the stabilization of hyperthyroidism.
The onset of ophthalmopathy is, however, unpredictable. Ophthalmopathy is the result of changes in the endo-orbital components. Oedema of connective tissue surrounding the extra-ocular muscles, and oedema of the muscles, lead to increased of orbital fat and muscle volume and, therefore, to protrusion of the globe.
Exophthalmos may be associated with the following clinical findings: eyelid oedema, conjunctivitis, photophobia, chemosis, lagophthalmos, headache, gritty sensation, retrobulbar pain and tearing. Oedema and prolapse of the lacrimal gland may also occur. Hyperthyroidism should be stabilized for a minimum of six months, before performing surgery.
Surgery can be performed with different techniques:
– osseous expansion, in order to increase the volume of the intra-orbital space.
– intra-orbital fat removal, in order to reduce the endo-orbital content.
– combination of two or more techniques.
Osseous expansion is performed by means of a three-wall removal (lateral, medial and inferior), via transpalpebral , or more rarely, via coronal.
Removal of intraorbital fat follows the Olivari’s technique: decompression by means of intra and extraconal lypectomy through lower and upper eyelid incisions. Generally one orbit at a time is treated. The other can be operated after 4-5 days. Additional techniques (i.e. lengthening of the levator muscle of the upper lid and correction of the retraction of lower lid) are essential in order to achieve satisfactory cosmetic and functional results. Residual diplopia must be evaluated by the ophthalmologist and eventually treated after 8-10 months.