Luciano Mastronardi

Intramedullary spinal cord ependymomas — a study of 45 cases with long-term follow-up

SummaryOf the 62 patients with intramedullary spinal cord ependymoma treated surgically at our Neurosurgery Division between January 1951 and December 1990 45 had a follow-up of at least 3 years and the longest 30 years. The 28 conus-cauda equina-filum ependymomas operated during the same period are not considered in this study. An analysis of our cases and of the larger published series shows that favourable prognostic factors, apart of course from total tumour removal, which is now usually possible, are a site below the high cervical segments and a mild pre-operative symptom pattern. Patient age at diagnosis, tumour size and “low dose” (< 40 Gy) radiotherapy seem to have no influence on the prognosis. Aggressive surgical removal is the treatment of choice and also for long-term recurrence.

Ki-67 labelling index and invasiveness among anterior pituitary adenomas: analysis of 103 cases using the MIB-1 monoclonal antibody.

AIMS: To investigate the relation between proliferative activity of anterior pituitary adenomas, quantified by the Ki-67 labelling index, and their invasive behaviour. METHODS: Expression of Ki-67 was evaluated in 103 anterior pituitary adenomas consecutively operated on in a 36 month period and correlated with surgical evidence of invasiveness. RESULTS: Non-invasive (n = 65) and invasive (n = 38) adenomas were identified from surgically verified infiltration of sellar floor dura and bone. The wall of the cavernous sinus was infiltrated in 16 cases. Forty one adenomas were non-functioning and 62 functioning (24 prolactin, 21 growth hormone, 10 ACTH, seven mixed). The overall mean (SD) Ki-67 labelling index was 2.64 (3.69) per cent (median 1.5). The mean index was 3.08 (4.59) per cent in functioning and 1.97 (1.78) per cent in non-functioning tumours; 5.47 (9.52) per cent in ACTH adenomas and 2.33 (2.42) per cent in others (p = 0.01); 3.71 (5.17) per cent in invasive and 2.01 (2.45) per cent in non-invasive adenomas (p = 0.027); and 5.58 (7.24) per cent in cavernous sinus infiltrating v 2.10 (2.39) per cent in cavernous sinus non-infiltrating adenomas (p = 0.0005). To identify a value of labelling index beyond which adenomas should be considered invasive and another beyond which cavernous sinus infiltration should be suspected, normality Q-Q plots were obtained: a threshold labelling index of 3.5% for invasive adenomas and of 5% for cavernous sinus infiltrating adenomas was defined, with statistically significant differences (p = 0.02 and p = 0.004, respectively). CONCLUSIONS: The Ki-67 labelling index can be considered a useful marker in determining the invasive behaviour of anterior pituitary adenomas.

Prognostic relevance of the postoperative evolution of intramedullary spinal cord changes in signal intensity on magnetic resonance imaging after anterior decompression for cervical spondylotic myelopathy

OBJECT Areas of intramedullary signal intensity changes (hypointensity on T1-weighted magnetic resonance [MR] images and hyperintensity on T2-weighted MR images) in patients with cervical spondylotic myelopathy (CSM) have been described by several investigators. The role of postoperative evolution of these alterations is still not well known. METHODS A total of 47 patients underwent MR imaging before and at the end of the surgical procedure (intraoperative MR imaging [iMRI]) for cervical spine decompression and fusion using an anterior approach. Imaging was performed with a 1.5-tesla scanner integrated with the operative room (BrainSuite). Patients were followed clinically and evaluated using the Japanese Orthopaedic Association (JOA) and Nurick scales and also underwent MR imaging 3 and 6 months after surgery. RESULTS Preoperative MR imaging showed an alteration (from the normal) of the intramedullary signal in 37 (78.7%) of 47 cases. In 23 cases, signal changes were altered on both T1- and T2-weighted images, and in 14 cases only on T2-weighted images. In 12 (52.2%) of the 23 cases, regression of hyperintensity on T2-weighted imaging was observed postoperatively. In 4 (17.4%) of these 23 cases, regression of hyperintensity was observed during the iMRI at the end of surgery. Residual compression on postoperative iMRI was not detected in any patients. A nonsignificant correlation was observed between postoperative expansion of the transverse diameter of the spinal cord at the level of maximal compression and the postoperative JOA score and Nurick grade. A statistically significant correlation was observed between the surgical result and the length of a patients clinical history. A significant correlation was also observed according to the preoperative presence of intramedullary signal alteration. The best results were found in patients without spinal cord changes of signal, acceptable results were observed in the presence of changes on T2-weighted imaging only, and the worst results were observed in patients with spinal cord signal changes on both Tl- and T2-weighted imaging. Finally, a statistically significant correlation was observed between patients with postoperative spinal cord signal change regression and better outcomes. CONCLUSIONS Intramedullary spinal cord changes in signal intensity in patients with CSM can be reversible (hyperintensity on T2-weighted imaging) or nonreversible (hypointensity on T1-weighted imaging). The regression of areas of hyperintensity on T2-weighted imaging is associated with a better prognosis, whereas the T1-weighted hypointensity is an expression of irreversible damage and, therefore, the worst prognosis. The preliminary experience with this patient series appears to exclude a relationship between the time of signal intensity recovery and outcome of CSM.

Neurinoma of the third, fourth, and sixth cranial nerves: A survey and report of a new fourth nerve case

A rare case of trochlear nerve neurinoma is described. Including this case, the number of reported intracranial tumors arising from the sheaths of the third, fourth, and sixth cranial nerves is 38. By site and relationship to the nerve segment, they fall into three groups: cisternal, cisternocavernous, and cavernous. In cisternal tumors of the third and sixth nerves, paresis of the nerve hosting the tumor is the unique nerve deficit; by contrast, in those of the fourth nerve, paresis of the trochlear nerve can be absent and that of the third nerve present. In the latter tumors, a peculiar ataxic hemiparesis syndrome is produced by midbrain compression. Cisternocavernous neurinomas often cause symptoms of intracranial hypertension, while cavernous neurinomas bring about two clinical features: paresis of one or more nerves of the cavernous sinus and a clinicoradiological orbital apex syndrome. At surgery, generally cisternal neurinomas are totally removed and the nerve source of the tumor identified; in cisternocavernous and cavernous neurinomas, total removal of tumor and identification of the parent nerve have been reported in only half of the cases. In the majority of parasellar neurinomas, clinical differences can be found between those arising from the nerves governing eye movement and those arising from the gasserian ganglion.

Anterior cervical fusion with polyetheretherketone (PEEK) cages in the treatment of degenerative disc disease. Preliminary observations in 36 consecutive cases with a minimum 12-month follow-up

SummaryStudy design. Retrospective analysis of 36 cases of degenerative disc disease treated by interbody fusion with polyetheretherketone (PEEK) cages.Objective. To determine the safety and efficiency of PEEK cages for anterior cervical fusion (ACF).Summary of background data. ACF with autologous bone has been reported since over 50 years ago. The recent development of cages housing materials inducing osteogenesis simplifies the technique of interbody fusion. The main purposes of bone substitutes for ACF are immediate biomechanical support, osteo-integration of the graft, and elimination of local side effects at the donor site. This report shows our results using PEEK cages.Materials and methods. During an 18-month period, 36 consecutive patients had cervical fusions at 43 levels between C3 and C7. All operations involved one or two disc spaces for degenerative disc disease. We implanted all disc spaces with PEEK cages (Stryker Corporation, Kalamazoo, MI) containing granulated coralline hydroxylapatite (Pro-Osteon 200, Interpore Cross International, Irvine, CA) or deantigenated pig bone in a gel solution (Gen-Os, Tecnoss, Torino, Italy).Results. About 97% of patients had a good to excellent outcome; the result in one myelopathic patient was fair. The cervical fusion rate was 16.7% at 3 months, 61.1% at 6 months, and 100% at one year.Conclusions. PEEK cages appear to be safe and efficient for ACF. In order to confirm our preliminary impressions studies on larger series with long term follow-up are warranted.

Cerebral meningiomas in children.

Cerebral meningiomas are rare tumors in children that represent 1.4% of CNS tumors and 1.5% of intracranial meningiomas. We have analyzed 197 cases of cerebral meningiomas under 16: 178 cases were taken from the available literature and 19 from our series. When comparing pediatric meningiomas with those of adults, we noted some differences. Before the age of 16 there is a slight preference for males; the intraventricular variety is more frequent; cystic meningiomas and the absence of dural attachment are more frequent findings; the neuroradiological diagnosis is more difficult.

Pre-surgical planning and MR-tractography utility in brain tumour resection.

The purposes of this study were (1) to evaluate the possible identification of trajectories of fibre tracts, (2) to examine the useful of a neuronavigation system for pre-surgical planning, (3) to assess pre- and post-surgery patients’ clinical condition and (4) to evaluate the impact of this information on surgical planning and procedure. Twenty-eight right-handed patients were prospectively and consecutively studied. All the patients were clinically assessed by a neurologist in both pre- and post-surgical phases. Separately the pyramidal tract, optic radiation and arcuate fasciculus were reconstructed. The trajectories were considered suitable for surgical planning if there were no interruptions of any of the layers at the level of the lesion. Dedicated software ‘merged’ the acquired images with the tractographic processing, and the whole dataset was sent to the neuronavigation system. The assessment of the 37 visualised trajectories close to the tumour resulted in a modification of the surgical approach to corticotomy in six patients (21%); the impact on the definition of the resection margins during surgery was 64% (18 cases). The overall impact percentage on the surgical procedure was 82%. In 27 cases, the symptoms had not changed. MR-tractography provides the neurosurgeon with a new anatomical view that has an impact on the surgical resection planning for brain neoplasms.

Cerebral cavernous angioma in children

Cerebral cavernous angioma is a rare vascular malformation at any age and is very rare in childhood. In the literature available to us, we have been able to trace only 50 cases, to which we have added the 6 cases from our own series. The incidence in pediatric group is higher at 0–2 years (26.8%) and at 13–16 years (35.7%). The clinical onset shows epilepsy in 45.4% of cases, hemorrhagic syndrome in 27.3%, intracranial hypertension in 16.4%, and focal neurological deficits in 10.9%. Furthermore, we discuss the neuroradiological features (CT, angiography, and MRI) and the therapy of pediatric cavernous angioma.

Lack of correlation between Ki-67 labelling index and tumor size of anterior pituitary adenomas.

Aims and backgroundThe Ki-67 is a nuclear antigen detected by the monoclonal antibody MIB-1 and its Labeling Index (LI) is considered a marker of normal and abnormal cell proliferation. Pituitary adenomas are generally well differentiated neoplasms, even if in about one third of cases they are invasive of surrounding tissues. The aim of this study is to evaluate the correlation between Ki-67 labelling index and tumor size of pituitary adenomas extimated by means CT and MRI and confirmed at operation.MethodsUsing the monoclonal antibody MIB-1, we evaluated the expression of Ki-67 in 121 anterior pituitary adenomas consecutively operated on in a 48-month period.ResultsIn relation to neuroradiological (CT and MRI) and surgically verified tumor size, we identified 24 microadenomas, 27 intrasellar macroadenomas, 34 intra-suprasellar macroadenomas, and 36 intra-supra-parasellar macroadenomas. The adenomas were non-infiltrating (76 cases) and infiltrating (45 cases) adenomas. The wall of the cavernous sinus (CS) was infiltrated in 18 cases. Forty-eight adenomas were non-functioning and 73 functioning. The overall mean ± SD Ki-67 LI was 2.72 ± 2.49% (median 1.6). It was 2.59 ± 1.81 in microadenomas, 2.63 ± 3.45 in intrasellar macroadenomas, 1.91 ± 2.11 in intra-suprasellar macroadenomas, and 3.29 ± 5.45 in intra-supra-parasellar macroadenomas (p = 0.27). It was 3.73 ± 5.13% in infiltrating and 2.03 ± 2.41% in non-infiltrating adenomas (p = 0.02), and 5.61 ± 7.19% in CS-infiltrating versus 2.09 ± 2.37% in CS-non-infiltrating adenomas (p = 0.0005).ConclusionsOur preliminary results seem to exclude significative correlations between Ki-67 LI and tumor size of anterior pituitary adenomas, even if this index can be considered a useful marker in the determination of the infiltrative behaviour of these tumors.

Intracranial meningiomas in the 9th decade of life: a retrospective study of 17 surgical cases.

The general availability of cerebral computed tomographic and magnetic resonance imaging scans makes the observation of symptomatic intracranial meningiomas in very elderly patients (aged 80 yr or more) relatively frequent. A few authors have reported on patients who have undergone surgery for intracranial meningiomas in their 9th decade of life, without providing indications regarding the surgical criteria and the prognostic factors. We report on a series of 17 patients who have received surgery for intracranial meningiomas in their 9th decade of life, with the goal of determining some surgical criteria for general physicians and neurosurgeons. Patients with severe systemic disease and definite functional limitations (American Society of Anesthesiology Class III) had a major postoperative morbidity (P = 0.020) and mortality (P = 0.005), especially if they scored low (< 70) on the preoperative Karnofsky Rating Scale (P = 0.010). The risk of postoperative morbidity was higher when the maximum diameter of the tumor was > 5 cm (P = 0.031).