"Ptose" é o termo médico para uma pálpebra superior caída. Há duas razões pelas quais uma pálpebra cai: há um problema com os músculos elevadores que levantam as pálpebras, ou um problema com o nervo que os controla. Há várias causas - trauma, infecção, câncer, doença autoimune ou inflamatória, e às vezes a ptose pode ser hereditária.
É causada por uma disfunção tanto nos músculos que levantam a pálpebra, quanto nos nervos que controlam esses músculos. A ptose pode ocorrer por si só, mas também pode estar associada a trauma, doença autoimune ou inflamatória, infecção, câncer e, em alguns casos, doença hereditária.
Às vezes, a ptose é leve, e a pálpebra superior cai apenas ligeiramente. Mas em casos moderados a graves, a pálpebra superior pode cobrir parcial ou completamente a pupila. Isto é particularmente preocupante em crianças, a ptose que cobre a pupila pode causar ambliopia: a parte do cérebro que lida com a visão daquele olho simplesmente não se desenvolve adequadamente, pois não está recebendo tanta informação deste olho parcialmente fechado.
Instintivamente, as crianças tentam compensar isso através dos seguintes comportamentos:
Mas se você tem uma criança com uma pálpebra que cobre a pupila e eles não usam estes mecanismos compensatórios, então é importante que eles sejam vistos por um profissional rapidamente: a ptose pode causar supressão visual, e pode deixar sua criança com ambliopia permanente e vitalícia.
A ptose congênita é geralmente baseada em uma má formação do músculo (músculo elevador), que deve elevar a pálpebra superior. Esta alteração pode afetar uma ou ambas as pálpebras superiores. Outras causas mais raras de ptose congênita podem incluir: certas doenças musculares, tumores das pálpebras ou distúrbios neurológicos.
There are two surgical techniques that can be used to correct ptosis – levator resection and frontal suspension. Which one is chosen depends on the condition of the levator muscle and the extent of ptosis. After we examine you, we will discuss the findings together with you and plan the further procedure for you (or your child).
If the function of the levator muscle is still relatively intact, we will suggest what’s called levator resection: the levator muscle is shortened and strengthened. We do this by making a cut in the eyelid crease, then shortening the levator muscle by a predetermined and precisely defined length. The incision is later closed with self-dissolving stitches, and the entire operation is performed under general anaesthesia
If the function of the levator muscle is weak, we typically perform what’s called frontalis suspension surgery. The surgeon places a sling under the muscle and connects it with the eyebrow. This loop is inserted through small, approximately 5 mm-long punctures over the eyebrows and in the upper lid area. This sling is then tightened until the position of the upper lid reaches the desired height. The punctures on the eyebrows are closed with self-resecting sutures – those in the eyelid heal without suture. The operation is performed under general anaesthesia.
If the ptosis is mild and the eye is not in danger of developing amblyopia, the operation can be postponed, and we will monitor the situation before intervening. However, we would suggest that the operation be considered at the onset of puberty, in order to relieve the psychological pressure on your child that other children might place on your child.
However, if your child’s vision is at risk, early surgery is needed to support normal vision and prevent amblyopia.
We aim for perfection, but it’s important to realize that in about 15% of cases where we’ve operated on one or two eyelids, we might have a good result, but thanks to the healing processes potentially changing lid height, the patient might still end up with a small asymmetry between the eyelid opening height of both eyes. Having said that, these small differences are natural – many people have this, and this should be tolerated, especially because the final lid height is only stable after about 6 months after surgery – until then, it might appear that there is under- or over-correction. If there is still a clear difference after 6 months (> 2mm), then, if appropriate, we will suggest a re-operation.
In acquired ptosis in adulthood, the levator muscle functions normally and “only” needs to be raised to the correct height. In children with congenital ptosis, the eyelid muscle doesn’t work sufficiently well enough to lift the eyelid completely. Raising the muscle alone is not enough: the muscle must be shortened. This results in a normal-looking eyelid height when looking straight ahead, but the upper eyelid “stops” moving below that level when looking down. This is called “lid lag” and unavoidable – but your child will learn to compensate for this after surgery so that the lid lag is not too noticeable.
