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Neurosurgery
between the cranial nerves and the tumour could be found. In 187 recommend initial treatment on the side with the smaller tumour or the
cases (89%), the facial nerve could be separated from the VS and its side with the better hearing level. If the hearing and the tumour size are
continuity preserved. similar on both sides, our decision is based on the pre-operative ABR.
The side with better quality is operated on first, because the chances of
Hearing Preservation successful hearing preservation are better on that side. Thus, we
A more conservative approach has been put forward in order to achieved bilateral hearing preservation in 23% of the patients, and
preserve hearing, i.e. simple observation of the patient and subtotal preserved unilateral hearing after surgery in 65% of the patients, who
intracapsular resection if the VS increases.
12
Some surgeons advise that had a useful pre-operative hearing level. For VS on the only hearing side
surgery should be postponed for as long as possible. Furthermore, we offer IAC decompression and complete or partial tumour removal,
hearing conservation attempts should be performed on the side with depending on the intra-operative ABR. If slight microsurgical actions are
the larger tumour, and surgery on the better hearing ear is to be followed by severe deterioration in ABR, only partial resection is
avoided. If this treatment strategy is followed, surgery is usually performed. With this strategy we succeeded in preserving hearing in 15
performed when the tumours have reached a considerable size, which patients. Follow-up examinations indicated that preserved hearing
significantly worsens the outcome. We accept an initial observational remained functional for periods of up to 15 years. Tumour regrowth has
period in selected cases, such as the elderly, those with poor surgical been moderate and has not necessitated re-operations.
risks or those who refuse surgery.
Radiosurgery is another treatment option. It provides tumour control
in up to 81% of patients at 10 years and hearing preservation of
approximately 33–43%, although some deterioration occurs during
Our treatment philosophy is based
the ensuing six years.
18
In our opinion, radiosurgery is not the optimal
on the assumption that surgical
primary therapy in NFII. It is best reserved for NFII patients who have
particularly aggressive tumours, those with medical contraindications
removal of vestibular schwannomas
for microsurgery, patients who refuse surgery or the elderly.
10,11,16
can preserve hearing.
Bilateral deafness of NFII patients is often inevitable. The introduction
of the auditory brainstem implant in the clinical practice offers hope
for such patients.
19
A recently introduced promising alternative to
Proponents of the active treatment strategy state that surgical removal auditory brainstem implants is the auditory mid-brain implant.
10,20
of bilateral VS should occur as early as possible if the tumour is small
(up to 1.5cm), the hearing is usable and hearing preservation is All patients with NFII – and their families – should have access to
possible.
10,16,18
Our treatment philosophy is based on the assumption genetic testing because early, preferably pre-symptomatic, diagnosis
that surgical removal of VS can preserve hearing. Our goal has always improves clinical outcome. Some authors even suggest that MR
been the preservation of functional hearing for as long as possible. If tomography scanning for members of NFII families should start at
the chances of functional hearing preservation are realistic, our 10–12 years of age.
15
recommendation is for early surgery. Tumour extension, audiometry
data and auditory brainstem responses (ABR) determine which side Treatment of NFII patients should be individualised and performed in
should be operated on initially. The side with the best chance for specialised treatment centres. Close collaboration with the patient and
hearing preservation is treated first. his or her family is essential. The attitude and expectations of patients
should guide the decision-making process. Carefully individualised
The main predictors of successful hearing preservation are tumour treatment strategies offer the possibility of prolongation of life and
extension, pre-operative hearing level and the quality of ABR. We preservation of neurological functions. ■
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4. Al-Otibi M, Rutka JT, Neurosurgical implications of neurofibro- 11. Baser ME, Gareth DR, Evans DG, Gutmann DH, 18. Mathieu D, Kondziolka D, Flickinger JC, et al., Stereotactic
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16 EUROPEAN NEUROLOGICAL DISEASE 2007
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