Cesare Colosimo

Evidence for a possible neuroanatomical basis for lexical processing of nouns and verbs

Neuropsychological studies have revealed that brain-damaged patients may show impairments of specific word categories. This study reports the performance of three patients with impairments of the categories noun and verb. The first and second patients, with left frontal lobe atrophy, were impaired in naming and comprehension of verbs. The third patient, with striking atrophy of the left temporal lobe, was disproportionately impaired in naming and comprehension of nouns. These findings suggest that anatomically distinct neural systems in the temporal and frontal lobes of the dominant hemisphere might play a critical role in lexical processing of nouns and verbs, respectively.

Surgical Treatment of Craniopharyngiomas: An Evaluation of the Transsphenoidal and Pterional Approaches

Fifty-seven patients with craniopharyngiomas underwent a total of 64 operations. Their clinical follow-up ranged from 2.5 to 15.5 years, with a mean follow-up of 6.5 years. A transsphenoidal approach was used in 35 patients (61%), whereas 22 (39%) were operated on using a pterional approach (in 16 patients, the tumor was found in the suprasellar cisterns, and in 6, the tumor was found in the third ventricle and was removed passing through the lamina terminalis). Total removal of the tumor was achieved in 43 patients (75%). In six patients (11%), fragments of the capsule remained attached to the hypothalamus (subtotal removal), and, in eight patients (14%), the tumor was partially removed. No recurrence occurred in those patients in whom removal was total. Regrowth was observed in two patients (33%) in whom removal was subtotal and in two (25%) in whom removal was partial. Three of them underwent subsequent operations, and a total removal with good clinical outcome was achieved. All patients except two had good postoperative recovery. Twenty patients (35%) required hormonal replacement therapy. When transsphenoidal surgery was used, a total removal of the tumors was achieved in 23 (66%) of the patients. Good clinical outcome was seen in all 35 patients. Six patients (17%) required hormonal replacement therapy. When the pterional approach was used for tumors in the suprasellar cisterns, we achieved total removal of tumors in 15 patients (94%). Good clinical outcome was seen in 20 patients (91%). Eleven patients (50%) required hormonal replacement therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

High Response Rate to Cisplatin/Etoposide Regimen in Childhood Low-Grade Glioma

PURPOSE The aim of this study was to avoid radiotherapy and to induce an objective response in children with low-grade glioma (LGG) using a simple chemotherapy regimen based on cisplatin and etoposide. PATIENTS AND METHODS Thirty-four children (median age, 45 months) with unresectable LGG were treated with 10 monthly cycles of cisplatin (30 mg/m(2)/d on days 1 to 3) and etoposide (150 mg/m(2)/d on days 1 to 3). Tumor originated in the visual pathway in 29 patients, in the temporal lobe in two, in the frontal lobe in two, and in the spine in one. Eight children were affected by neurofibromatosis type 1. Objective tumor response and toxicity were evaluated by magnetic resonance imaging and neurologic and functional tests at 3-month intervals. RESULTS An objective response was obtained in 24 (70%) of 34 patients, whereas the others had stable disease. None of the children were electively irradiated. In 31 previously untreated children, overall survival was 100% and progression-free survival was 78% at 3 years, with a median follow-up of 44 months. Acute toxicity was unremarkable; 28% patients evaluated for acoustic neurotoxicity revealed a loss of perception of high frequencies. CONCLUSION Cisplatin and etoposide combined treatment is one of the most active regimens for LGG in children and allows avoidance of radiotherapy in the vast majority of patients.

Surgical Treatment of Craniopharyngiomas

ABSTRACTFIFTY-SEVEN PATIENTS WITH craniopharyngiomas underwent a total of 64 operations. Their clinical follow-up ranged from 2.5 to 15.5 years, with a mean follow-up of 6.5 years. A transsphenoidal approach was used in 35 patients (61%), whereas 22 (39%) were operated on using a pterional approach

Giant prolactinomas in men: efficacy of cabergoline treatment

objective The term ‘giant prolactinoma’ can be used for tumours larger than 4 cm in diameter and/or with massive extrasellar extension. Cabergoline (CAB), a long‐lasting dopamine agonist (DA), safe and well tolerated, is effective in normalizing PRL levels and inducing tumour shrinkage in micro‐ and macroprolactinomas. The purpose of this prospective study was to evaluate the efficacy and safety of CAB also for giant prolactinomas.

Craniopharyngiomas of the third ventricle : Trans-lamina terminalis approach

OBJECTIVECraniopharyngiomas usually grow on the cisternal surface of the hypothalamic region; these tumors can also grow from the infundibulum or tuber cinereum on the floor of the third ventricle, developing exclusively into the third ventricle. The aim of the present work was to establish the usefulness of the pterional trans-lamina terminalis approach for the removal of these tumors. METHODSEight patients who were surgically treated for craniopharyngiomas located exclusively within the third ventricle were considered. The initial symptoms were acute hydrocephalus in two cases, psychological disturbances in two, amenorrhea in two, headaches in one, and hypopituitarism in one. The diagnoses were established, in all cases except one, with magnetic resonance imaging. In all cases, the tumor completely filled the third ventricle. RESULTSTotal removal of the lesion was achieved in seven cases. One patient underwent partial removal. In the immediate postoperative period, no major complications were observed. Five patients required replacement hormonal therapy. All patients returned to a normal life. Many months after surgery, two patients exhibited psychological disturbances and died, the first because of voluntary withdrawal of replacement therapy (12 mo after surgery) and the second because of a severe imbalance in body fluids and electrolytes, with a subsequent hyperosmolar coma (27 mo after surgery). Only one patient who underwent initial total removal experienced a small recurrence of the lesion (30 mo after surgery); after 3 years, the lesion exhibited unchanged size. CONCLUSIONIn our experience, the trans-lamina terminalis approach is a valid choice for the removal of purely intraventricular craniopharyngiomas. These tumors can be removed without significant sequelae related to the surgical approach. The proximity to the hypothalamus requires accurate neuroendocrine and electrolyte control in the postoperative period, in some cases even years after surgery.

Management of Recurrent Craniopharyngioma

SummaryAlthough histologically benign, craniopharyngioma can regrow either from macroscopic remnants of the tumour left behind at operation, or even after an apparently gross total removal. Recurrence rates vary significantly in the literature, depending on the efficacy of surgical treatment and also on the growth potential of the tumour itself. The main factor influencing tumour regrowth is obviously the extent of surgical resection, as total removal carries a much lesser risk of recurrence compared to subtotal or partial resections (although in such cases radiation therapy can lower this risk significantly). Other factors involved are the duration of follow-up and patients age at operation, as children tend to relapse more frequently than adults. Even in the “microsurgery” era, characterized by high percentages of total resections, recurrences remain high and continue to represent a major problem of craniopharyngioma treatment.Twenty-seven children and adolescents were operated on for craniopharyngioma at the Department of Neurosurgery, Section of Pediatric Neurosurgery, Catholic University Medical School, Rome, between June 1985 and June 1997. Total tumour resection was achieved in 18 cases, subtotal in 7 and partial 2 instances. One patient died post-operatively. Post-operative neuroradiological investigations confirmed the operative findings, although 3 children with an apparently gross total removal showed a residual non-enhancing calcium fleck adherent to the hypothalamus (which remained stable at the following examinations). Three of the 9 patients with less than total removal underwent post-operative radiation therapy. Out of the 26 surviving patients 6 presented a recurrence of their craniopharyngioma, 2 after an apparently gross total removal and 4 after a subtotal or partial resection (one of them had received radiation therapy). The diagnosis was merely neuroradiological in 5 cases, as only one child presented a clinical picture suggestive of tumour regrowth.Surgery was the first therapeutic option in all cases. Total tumour resection was accomplished in 3 cases, subtotal in 2 and partial in the last one. One child died post-operatively. Four of the 5 survivors received radiation therapy. All the patients are presently alive and stable (mean follow-up: 5.6 yrs). The authors conclude that surgery should be the first therapeutic option in case of recurrent craniopharyngioma and that radiation therapy should also be considered but only as adjuvant therapy.

Seizure-induced brain lesions: a wide spectrum of variably reversible MRI abnormalities.

Introduction MRI abnormalities in the postictal period might represent the effect of the seizure activity, rather than its structural cause. Material and Methods Retrospective review of clinical and neuroimaging charts of 26 patients diagnosed with seizure-related MR-signal changes. All patients underwent brain-MRI (1.5-Tesla, standard pre- and post-contrast brain imaging, including DWI-ADC in 19/26) within 7 days from a seizure and at least one follow-up MRI, showing partial or complete reversibility of the MR-signal changes. Extensive clinical work-up and follow-up, ranging from 3 months to 5 years, ruled out infection or other possible causes of brain damage. Seizure-induced brain-MRI abnormalities remained a diagnosis of exclusion. Site, characteristics and reversibility of MRI changes, and association with characteristics of seizures were determined. Results MRI showed unilateral (13/26) and bilateral abnormalities, with high (24/26) and low (2/26) T2-signal, leptomeningeal contrast-enhancement (2/26), restricted diffusion (9/19). Location of abnormality was cortical/subcortical, basal ganglia, white matter, corpus callosum, cerebellum. Hippocampus was involved in 10/26 patients. Reversibility of MRI changes was complete in 15, and with residual gliosis or focal atrophy in 11 patients. Reversibility was noted between 15 and 150 days (average, 62 days). Partial simple and complex seizures were associated with hippocampal involvement (p=0.015), status epilepticus with incomplete reversibility of MRI abnormalities (p=0.041). Conclusions Seizure or epileptic status can induce transient, variably reversible MRI brain abnormalities. Partial seizures are frequently associated with hippocampal involvement and status epilepticus with incompletely reversible lesions. These seizure-induced MRI abnormalities pose a broad differential diagnosis; increased awareness may reduce the risk of misdiagnosis and unnecessary intervention.

The contribution of magnetic stimulation of the motor cortex to the diagnosis of cervical spondylotic myelopathy. Correlation of central motor conduction to distal and proximal upper limb muscles with clinical and MRI findings

Magnetic stimulation of the motor cortex and cervical spine was performed on 24 patients with cervical spondylotic myelopathy documented by MRI. Compound motor action potentials (CMAPs) were recorded from the biceps and thenar muscles to study the central motor pathways of two different myotomes, C5-C6 and C8-D1. Central motor conduction was abnormal in all 24 patients for thenar muscles and in 5 patients for biceps brachii. In patients with a single compression level, central motor conduction abnormalities were confined to the myotomes caudal to the site of compression documented by MRI, in both proximal and distal upper limb muscles in the patients with upper spondylotic compression, and in distal muscles only in the patients with lower compression. In the patients with multilevel compression, central motor conduction time was abnormal for thenar muscles and always normal for the biceps muscle, but its mean value was significantly greater than in the control subjects, suggesting a slight involvement of central motor pathways for proximal upper limb muscles and major damage of the lower cervical segments. Owing to their high degree of sensitivity, central motor conduction studies may be of considerable value in the functional assessment of central motor pathways in cervical spondylotic myelopathy.

Contrast-Enhanced MR Imaging of Brain Lesions: A Large-Scale Intraindividual Crossover Comparison of Gadobenate Dimeglumine versus Gadodiamide

BACKGROUND AND PURPOSE: The higher relaxivity of gadobenate dimeglumine compared with gadodiamide is potentially advantageous for contrast-enhanced brain MR imaging. This study intraindividually compared 0.1-mmol/kg doses of these agents for qualitative and quantitative lesion enhancement. MATERIALS AND METHODS: Adult patients with suggested or known brain lesions underwent 2 identical MR imaging examinations at 1.5T, one with gadobenate dimeglumine and the other with gadodiamide. The agents were administered in randomized order separated by 3–14 days. Imaging sequences and postinjection acquisition timing were identical for the 2 examinations. Three blinded readers evaluated images qualitatively for diagnostic information (lesion extent, delineation, morphology, enhancement, and global preference) and quantitatively for contrast-to-noise ratio (CNR). RESULTS: One hundred thirteen of 138 enrolled patients successfully underwent both examinations. Final diagnoses were intra-axial tumor, metastasis, extra-axial tumor, or other (47, 27, 18, and 21 subjects, respectively). Readers 1, 2, and 3 demonstrated global preference for gadobenate dimeglumine in 63 (55.8%), 77 (68.1%), and 73 (64.6%) patients, respectively, compared with 3, 2, and 3 patients for gadodiamide (P < .0001, all readers). Highly significant (P < .0001, all readers) preference for gadobenate dimeglumine was demonstrated for all qualitative end points and for CNR (increases of 23.3%–34.7% and 42.4%–48.9% [spin-echo and gradient-refocused echo sequences, respectively] for gadobenate dimeglumine compared with gadodiamide). Inter-reader agreement was good for all evaluations (κ = 0.47–0.69). Significant preference for gadobenate dimeglumine was demonstrated for all lesion subgroup analyses. CONCLUSION: Significantly greater diagnostic information and lesion enhancement are achieved on brain MR imaging with 0.1-mmol/kg gadobenate dimeglumine compared with gadodiamide at an equivalent dose.