Navigation using anatomical landmarks for registration is a reliable method in the localization of the TSSJ for retrosigmoid craniotomies and thereby avoiding unnecessary sinus exposure. In addition, the method proved to be fast and accurate. The asterion was found to be a less accurate landmark for the localization of the TSSJ using navigation.

Our study confirms that NIV may be useful to avoid intubation in approximately 80% of patients with COPD complicated by moderate-severe hypercapnic respiratory failure.

This paper reports 15 examinations by magnetic resonance imaging (MRI) performed in pregnant women whose fetuses had cerebral malformations identified by sonography. In all the cases the fetuses were immobilized by ultrasound-guided intravenous or intramuscular curarization. The diagnoses by MRI and ultrasound differed only in one case where an occipital meningocele had first been suggested. No cerebral abnormalities were demonstrated in this case by the MRI study, and this was confirmed at birth. In the remaining 14 cases, MRI confirmed the ultrasound diagnosis of cerebral malformation. In four of these cases, MRI added some additional information to the ultrasound diagnosis of ventriculomegaly by detecting agenesis of the corpus callosum in two fetuses, one Chiari malformation and one triventricular hydrocephalus. Another two ultrasound diagnoses of microcephaly actually proved to be semilobar holoprosencephaly with MRI. In the following cases, the MRI diagnoses concurred with those of ultrasound, and was therefore used unnecessarily despite providing further anatomical details of the lesions: two cases of agenesis of the corpus callosum, one case of anencephaly, a cystic hygroma of the neck, an alobar holoprosencephaly, a Dandy-Walker malformation and a mild isolated hydrocephalus associated with diaphragmatic hernia. In one case of iniencephaly, sonography offered closer approximation to the correct diagnosis. The results obtained unequivocally confirm the high sensitivity of ultrasound examinations in the prenatal screening of cerebral malformations and show that MRI proves to be complementary in uncertain cases or when more accurate anatomical detail is required.

This report is a retrospective analysis of the surgical outcome of 15 patients (8 females, 7 males; mean age, 37.8 years) with residual or recurrent vestibular schwannomas operated on between 1987 and 2005. These 15 patients were part of a larger series of 252 consecutive vestibular schwannoma excisions. Tumors were classified as large (10) when their diameter exceeded 3.5 cm and giant (5) when their diameter exceeded 4.5 cm. All patients had previously undergone surgery. Hearing was lost in all cases, 8 had complete facial nerve palsy, 6 had trigeminal nerve deficits, 5 had cranial nerve IX and X palsy, and 10 had ataxic gait. Twelve patients had hydrocephalus. The tumors were reoperated through the retrosigmoid-transmeatal approach. The mean postoperative follow-up was 4.9 years. Complete resection was achieved in all patients. The facial nerve was preserved in 6 of the 7 patients with preoperative facial function. Transient worsening of bulbar cranial nerves palsy occurred in 2 cases. Cerebrospinal fluid leakage occurred in 3 patients. There were no deaths, and the tumors were histologically benign. Surgical removal is the only treatment for these lesions. Total resection associated with a low morbidity rate is possible. Preservation of the facial nerve is difficult due to severe scar tissue.

No abstract