The last revision of the NF2 criteria was done by M.J. Smith in 2017. This included the consideration of a LZTR1 mutation (schwannomatosis) instead of NF2 and excluded bilateral vestibular schwannomas that occur after 70 years of age. Treatment
Surgery
There are several different surgical techniques for the removal of acoustic neuroma. The choice of approach is determined by size of the tumour, hearing capability, and general clinical condition of the person. The retrosigmoid approach offers some opportunity for the retention of hearing. The translabyrinthine approach will sacrifice hearing on that side, but will usually spare the facial nerve. Post-operative cerebrospinal fluid leaks are more common. The middle fossa approach is preferred for small tumors and offers the highest probability of retention of hearing and vestibular function. Less invasive endoscopic techniques have been done outside of the United States for some time. Recovery times are reported to be faster. However, this technique is not yet mainstream among surgeons in the US.Larger tumors can be treated by either the translabyrinthine approach or the retrosigmoid approach, depending upon the experience of the surgical team. With large tumors, the chance of hearing preservation is small with any approach. When hearing is already poor, the translabyrinthine approach may be used for even small tumors. Small, lateralized tumours in people with NF2 with good hearing should have the middle fossa approach. When the location of the tumour is more medial a retrosigmoid approach may be better.
Cryptophthalmos is a rare congenital anomaly in which the skin is continuous over the eyeball with absence of eyelids. It is classified into three types: complete, incomplete and abortive. Failure of eyelid separation can be associated with maldevelopment of the underlying cornea and microphthalmia. Cryptophthalmos usually occurs on both sides and occurs in association with multiple other malformations collectively referred to as Fraser syndrome. References


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