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Fred J. Epstein and Memet Ozek

✓ A new instrument for use in surgically treating intra-axial neoplasms of the spinal cord and brain stem is described. The plated bayonet allows neoplastic tissue in the spinal cord to be separated from functioning neural elements without perforating the adjacent spinal cord. In addition, the plated bayonet facilitates exposure through the very small incision necessary to remove tumors of the brain stem without damaging cranial nerves or other vital structures.

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Congenital glioblastoma multiforme

Case report and review of the literature

Aşkin Şeker and M. Memet Özek

✓Congenital intracranial tumors are rare. If such a lesion is detected before birth, it is usually an incidental finding on fetal ultrasonography. The definition of a “congenital” tumor is controversial. The authors report the case of a “definite” congenital glioblastoma multiforme (GBM) diagnosed with the aid of ultrasonography and fetal magnetic resonance (MR) imaging in the 37th week of gestation. Postnatal MR imaging revealed a massive tumor occupying the patient’s left temporoparietooccipital area. Angiography was performed to assess vascularity and embolize the main feeding arteries. Surgery was performed, and the tumor was successfully excised completely.

The histopathological diagnosis of the tumor was GBM. An examination of the tumor cells revealed no p53 accumulation, a high MIB-1 index (87.5%), and no staining for epidermal growth factor receptor (EGFR). Adjuvant chemotherapy was administered, and the patient is doing well at 23 months of age.

Congenital GBM should be considered in the differential diagnosis in cases in which a fetal ultrasonography study or fetal MR image reveals a tumor, especially in the presence of intratumoral hemorrhage. Radical tumor removal, administration of adjuvant therapy, and biological findings (such as a lack of the overexpression of p53 and EGFR in the tumor cells) all point to a longer survival time.

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Adnan Dagcinar, Fatih Bayrakli, Ozlem Yapicier and Memet Ozek

✓ Primary meningeal osteosarcomas are rare tumors, with only 19 reported cases in the literature; only 4 of these, including the present case, are in pediatric patients. In this report, the authors present the case of an 8-year-old boy with a history of generalized tonic–clonic seizures who was found to harbor a meningeal osteosarcoma within the sylvian fissure. Initial working diagnoses included meningioma and glioma. After tumor enlargement and progressive symptoms, the patient underwent a large frontotemporal craniotomy and complete resection of the lesion, which recurred 6 and 12 months after the initial surgery and was surgically treated after each recurrence. The rarity of primary meningeal osteosarcomas can make their diagnosis difficult, and histopathological evaluation is mandatory for diagnosis. Because of their fast progression, they must be treated aggressively by means of surgery, chemotherapy, and radiotherapy.

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M. Necmettin Pamir, Koray Özduman, Alp Dinçer, Erdem Yildiz, Selçuk Peker and M. Memet Özek

Object

The authors describe the first shared-resource, 3-T intraoperative MR (ioMR) imaging system and analyze its impact on low-grade glioma (LGG) resection with an emphasis on the use of intraoperative proton MR spectroscopy.

Methods

The Acibadem University ioMR imaging facility houses a 3-T Siemens Trio system and consists of interconnected but independent MR imaging and surgical suites. Neurosurgery is performed using regular ferromagnetic equipment, and a patient can be transferred to the ioMR imaging system within 1.5 minutes by using a floating table. The ioMR imaging protocol takes < 10 minutes including the transfer, and the authors obtain very high–resolution T2-weighted MR images without the use of intravenous contrast. Functional sequences are performed when needed. A new 5-pin headrest–head coil combination and floating transfer table were specifically designed for this system.

Results

Since the facility became operational in June 2004, 56 LGG resections have been performed using ioMR imaging, and > 19,000 outpatient MR imaging procedures have been conducted. First-look MR imaging studies led to further resection attempts in 37.5% of cases as well as a 32.3% increase in the number of gross-total resections. Intraoperative ultrasonography detected 16% of the tumor remnants. Intraoperative proton MR spectroscopy and diffusion weighted MR imaging were used to differentiate residual tumor tissue from peritumoral parenchymal changes. Functional and diffusion tensor MR imaging sequences were used both pre- and postoperatively but not intraoperatively. No infections or other procedure-related complications were encountered.

Conclusions

This novel, shared-resource, ultrahigh-field, 3-T ioMR imaging system is a cost-effective means of affording a highly capable ioMR imaging system and increases the efficiency of LGG resections.

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Shlomo Constantini, John Houten, Douglas C. Miller, Diana Freed, Memet M. Ozek, Lucy B. Rorke, Jeffrey C. Allen and Fred J. Epstein

✓ Over a 13-year period extending from 1980 to 1993, 27 children less than 3 years of age underwent operation for removal of an intramedullary spinal cord tumor (IMSCT). The majority (18 of 27) of children had undergone surgery before being referred to New York University (NYU) Medical Center. The most common reasons for radiological investigation were pain (42%), motor regression (36%), gait abnormalities (27%), torticollis (27%), and progressive kyphoscoliosis (24%).

Forty procedures were performed in 27 children. Nine children underwent two operations and two children underwent three procedures. A gross-total resection was achieved in 72% of the procedures. There was no surgical mortality. A comparison of the preoperative and 3-month postoperative functional grades for the first NYU procedure (NYU-1) yielded the following findings: 20 patients' conditions remained the same, five patients improved, and two patients deteriorated. The functional outcomes of a second operation (NYU-2) were similar.

The majority of the children (24 of 27, 89%) had histologically determined low-grade lesions. There were 12 patients with low-grade astrocytomas (Grades I-III), eight with gangliogliomas, two with ganglioglioneurocytomas, one with a glioneurofibroma, and one child with a mixed astro/oligodendroglioma. Two children had anaplastic astrocytomas (Grades II–III) and one child had a glioblastoma multiforme.

In a median follow-up review of 76 months, two patients died and two patients were lost to follow up. The 3- and 5-year progression-free survival (PFS) rates were 81.7% (standard error of the mean (SEM) 0.083) and 76.2% (SEM 0.094), respectively. Eight of 24 patients suffered a recurrence within a mean time of 45.4 ± 28.9 months. All were treated with surgery (NYU-2). Lesions recurred in three of 12 children with low-grade astrocytomas, two of eight children with gangliogliomas, one child with an anaplastic astrocytoma, one child with a ganglioglioneurocytoma, and one child with a glioblastoma multiforme. At follow-up review, most of these children were doing well. Sixteen are in functional Grades I or II and 18 children attend a normal school system.

The authors conclude that surgery for the removal of IMSCTs in children less than 3 years of age can be performed radically and safely. The postoperative functional performance is determined by the degree of the preoperative deficit. It is, therefore, of utmost importance to diagnose and treat these children as early as possible. Spinal cord tumors should be recognized as potentially excisable lesions on their initial presentation and when they recur. The optimum treatment for malignant lesions is still to be determined.