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Mehmet Zileli, Cüneyt Hoscoskun, Priscilla Brastianos and Dündar Sabah


Sacral tumors are relatively rare, and experience related to resection of these tumors is therefore usually limited to a small number of patients. The purpose of this retrospective study was to review the authors' experience with sacral neoplasms over the last 12 years.


Based on a review of records in 11 patients who underwent sacrectomy, and the various patient characteristics, presenting symptoms, histological findings for their tumors, as well as the type of surgical treatment used (including a whole spectrum of sacral amputations), and their outcome are reported.


Despite the potential for complications, sacrectomy can be performed successfully, and is an important procedure in the treatment of primary sacral tumors.

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Mehmet Zileli, Sedat Çagli, Gülçin Basdemir and Yusuf Ersahin


Osteoid osteomas and osteoblastomas are rare primary bone tumors that usually do not arise in the spine. In this report the authors analyze 16 cases of osteoid osteoma or osteoblastoma of the spine that were surgically treated over a 27-year period.


A retrospective study was conducted in which the following data were found: five patients had osteoid osteomas (two male and three female patients) and 11 had osteoblastomas (seven male and four female patients). The site of the tumor was the cervical spine in four, thoracic in six, and lumbar spine in six. In 14 patients, the tumor involved the posterior vertebral elements, with lumbar and thoracic levels being the most common. Only two patients had tumors in the body of a cervical vertebra. The mean age of the patients was 20 years for osteoid osteoma and 19 years for osteoblastoma. The most common symptom was local pain in the area of the tumor. Among 11 patients with osteoblastoma, six (two with paraparesis, four with monoparesis) had neurological deficits caused by extradural compression. None of the patients with osteoid osteoma had neurological deficits. The diameters of osteoblastomas were 3 to 8 cm (mean 4 cm), and those of osteoid osteomas were 1.5 to 2 cm (mean 1.7 cm). Although the peritumoral bone was normal in patients with osteoblastoma, a sclerotic rim was observed in all patients with osteoid osteoma.

All patients were treated with resection; tumor excision was complete in 15 cases. Follow-up periods ranged from 2 months to 13 years (mean 36 months). Complete pain relief was achieved in 15 patients; the other patient described mild pain with activity. There was no tumor recurrence except one regrowth in a patient with osteoblastoma who then received radiation therapy. There were two complications: one surgery was performed at the wrong level, and there was one instrument failure that required revision.


With the help of modern imaging modalities that aid in diagnosis and surgical planning, a complete removal and cure may be achieved for most of these rare tumors.

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Mehmet Zileli, Fethi İdiman, Tufan Hiçdönmez, İzzet Övül and Erdem Tunçbay

✓ Brain-stem auditory evoked potentials (BAEP's) and blink reflexes (BR's) were recorded from 40 patients with clinical and radiological evidence of posterior fossa tumors. They were examined in three groups according to the anatomical location of the lesion: Group A included 15 patients with midline tumors; Group B included 14 patients with cerebellar hemispheric tumors; and Group C included 11 patients with cerebellopontine angle (CPA) tumors. More of the 40 patients had BAEP abnormalities (32) than BR abnormalities (24). All of the 11 patients with CPA tumors had some kind of BAEP and BR abnormalities. The 14 patients with cerebellar tumors showed the next most frequent abnormalities: 12 related to the BAEP's and seven to the BR's. The 15 patients with midline tumors showed the least number of abnormalities: nine related to BAEP's and six to the BR's.

In the analysis of BAEP wave latencies and interpeak latencies, a wave III latency delay occurred in all groups; latencies of waves IV and V were more significantly delayed in patients with CPA and cerebellar hemispheric tumors, and the interpeak latencies of waves III–V and I–V were markedly prolonged only in patients with CPA tumors (p < 0.01).

In all tumor groups, early response (R1) of BR's was significantly delayed in comparison to a healthy volunteer control group (p < 0.01), but R1 was more pronounced in cases of CPA tumors when compared with the other tumor groups. Although significant delays in direct and consensual late reflex components (R2) of BR's were noted in comparison to the control group, this delay could not differentiate one tumor group from another.

It can be concluded that, while these tests reflect the functions of different cranial nerves and brain-stem tracts, BAEP monitoring is more sensitive than BR testing for the detection of brain-stem involvement in posterior fossa tumors. Cerebellopontine angle tumors almost always cause severe abnormalities in both tests. Cerebellar hemispheric tumors and midline tumors cause fewer changes in both BAEP's and BR's.