Guido Trasimeni

Magnetic resonance imaging contribution for diagnosing symptomatic neurovascular contact in classical trigeminal neuralgia: A blinded case-control study and meta-analysis

Summary Patients with classical trigeminal neuralgia are more likely to have a symptomatic neurovascular contact when magnetic resonance imaging displays a root entry zone neurovascular contact associated with anatomical nerve changes. ABSTRACT Although classical trigeminal neuralgia (CTN) is frequently caused by neurovascular contact (NVC) at the trigeminal root entry zone (REZ), both anatomical and MRI studies have shown that NVC of the trigeminal nerve frequently occurs in individuals without CTN. To assess the accuracy of MRI in distinguishing symptomatic from asymptomatic trigeminal NVC, we submitted to high‐definition MRI the series of CTN patients referred to our outpatient service between June 2011 and January 2013 (n = 24), and a similar number of age‐matched healthy controls. Two neuroradiologists, blinded to the clinical data, evaluated whether the trigeminal nerve displayed NVC in the REZ or non‐REZ, whether it was dislocated by the vessel or displayed atrophy at the contact site, and whether the offending vessel was an artery or a vein. Our data were meta‐analyzed with those of all similar studies published from January 1970 to June 2013. In our sample, REZ contact, nerve dislocation and nerve atrophy were independently associated with CTN (P = .027; P = .005; P = .035 respectively). Compared to a rather low sensitivity of each of these items (alone or in combination), their specificity was high. When REZ contact and nerve atrophy coexisted, both specificity and positive predictive value rose to 100%. Meta‐analysis showed that REZ NVC was detected in 76% of symptomatic and 17% of asymptomatic nerves (P < .0001), whereas anatomical changes were detected in 52% of symptomatic and 9% of asymptomatic nerves (P < .0001). In conclusion, trigeminal REZ NVC, as detected by MRI, is highly likely to be symptomatic when it is associated with anatomical nerve changes.

Biochemical, clinical and neuroradiological (MRI) correlations in late-detected PKU patients.

SummaryBrain magnetic resonance imaging (MRI) was performed in 17 late-detected PKU patients (aged 2.8–25 years). Twelve subjects had been treated late (0.7–4.5 years), and 5 not at all. Four were still on diet when the study was performed. Mental development was normal in 4 subjects, mildly retarded in 6, and moderately or severely retarded in 7. None had exhibited mental or neurological deterioration. On MRI examination a symmetrical increase of T2-weighted signal in the periventricular white matter was found in all patients, although to different degrees. Concomitant signal decrease on the T1-weighted sequences was detected in 9 patients. Ten subjects showed focal white-matter abnormalities. A variable degree of cortical and subcortical atrophy was found in 12 subjects, and asymmetry of lateral ventricles in 4.White-matter involvement correlated with phenylalanine concentrations during the year preceding (rs=0.5706;p<0.02) and at the time of (rs=0.6182,p<0.01) the investigation. Cortical and subcortical atrophy correlated with the patients age (rs=0.5889,p<0.02, andrs=0.5929p<0.02, respectively).We conclude that late-detected PKU patients showed the same MRI abnormalities reported in early-treated subjects and in subjects who underwent neurological deterioration; white-matter abnormalities possibly result from the recent exposure to high phenylalanine concentrations; in late-detected PKU subjects cerebral atrophy could be the late result of chronic exposure to high phenylalanine concentrations.

Neuronal migrational disorders in children with epilepsy : MRI, interictal SPECT and EEG comparisons

Single-photon emission computed tomography (SPECT) is being increasingly used in the investigation of children with epilepsy and may provide insights into congenital malformations. We analyzed the interictal 99Tc-HMPAO-SPECT in a series of seven children with developmental disorders of the neocortex, each of them representing a prototype of cerebral dysgenesis, such as lissencephaly, pachygyria, opercular dysplasia, polymicrogyria, nodular heterotopia and band heterotopia. The patients studied were selected among 22 epileptic children with neuronal migrational disorders (NMDs). Interictal SPECT hypoperfusion was observed in the area homologous to MRI findings in all the examined children. In three patients low perfusion was also present in the opposite hemisphere, probably due to functional involvement or related to an underlying microdysgenesis, not revealed by structural imaging. EEG features were in agreement with low perfusion areas, both anatomically and functionally, in all children. In one patient hypoperfusion area differed from that revealed by MRI and EEG. Ictal SPECT has been considered a useful tool for accurately locating the epileptic focus. Nevertheless, interictal brain perfusion studies, together with proton magnetic resonance spectroscopy, may play an important role in detecting anatomic substrate in developmental disorders of the neocortex.

Magnetic resonance imaging of the parotid glands and lip biopsy in the evaluation of xerostomia in Sjögren's syndrome

Magnetic Resonance Imaging (MRI) of the parotid glands was performed in 23 patients with dry mouth. Each patient underwent lip salivary gland (LSG) biopsy and complete clinical and immunological assessment. MRI showed a quite specific nodular pattern in the parotid glands of patients with Sjögrens syndrome (SS), especially those with severe histologic abnormalities in LSG. However no significant correlation could be detected between MRI score and both LSG biopsy class and immunological abnormalities. MRI of the parotid glands can be regarded as a useful noninvasive procedure with high positive predictive value for the evaluation of the salivary component in SS.

Neuronal migrational disorders: diffuse cortical dysplasia or the “double cortex” syndrome

We report a 10‐year‐old girl who presented with a single episode of partial complex seizure. Neurological examination and psychological evaluation were normal. Electroencephalogram showed abnormalities in the left temporo‐occipital region. Magnetic resonance imaging revealed a bilateral layer of tissue iso‐intense with gray matter, between the wall of the lateral ventricle and the cortex, extending from the frontal to the occipital region, and enlarged left lateral ventricle. The images indicated diffuse cortical dysplasia, also known as band heterotopia or “double cortex”, and left cortical hemiatrophy.

Spinal arachnoiditis ossificans: Report of three cases

OBJECTIVE AND IMPORTANCE:Although the clinical and histological features of the pathological entity of spinal arachnoiditis ossificans (AO) have been established for some time, less attention has been paid to the treatment. We propose a classification of spinal AO evaluating the possibilities and indications for surgical or conservative treatment. CLINICAL PRESENTATION:Type III has a lumbar localization, presents with less neurological involvement, and usually requires conservative treatment. In Types I and II, which are usually thoracic, clinical worsening justifies surgical decompression or partial removal, whereas total removal is rarely achievable. INTERVENTION:The literature was reviewed, and the reports on three patients were added to the published cases. On the basis of a reappraisal of the computed tomographic and magnetic resonance imaging documentation and the surgical descriptions, the cases of AO were classified into three types: semicircular (Type I), circular (Type II), and englobing the caudal fibers (Type III). The indications for treatment were evaluated in terms of surgical possibilities and outcome. CONCLUSION:The classification proposed on the basis of radiological findings allows sufficient clinical differentiation of AO and evaluation of the possibilities for surgical treatment. The latter is conditioned by the type of arachnoiditis, degree of neurological involvement, and presence of any concomitant pathological findings.

Primary CNS demyelinating diseases in childhood : multiple sclerosis

We report on five children (three female and two male, age span 11–16 years) with laboratory-supported definite multiple sclerosis, or clinically definite multiple sclerosis, diagnosed on the basis of Poser and Paty criteria. All patients were subjected to serial clinical examinations, magnetic resonance investigations, CSF biochemical and immunological studies, and neurophysiological and neuropsychological assessments. Four of the five examined subjects underwent steroid treatment. Over a period of 3 years relapses have been observed in three of them. The first symptoms and signs of multiple sclerosis may be subtle and misleading; careful assessment of them may be crucial for an early diagnosis of the disease.

Spinal accessory nerve palsy due to neurovascular compression. Report of a case diagnosed by magnetic resonance imaging and magnetic resonance angiography

The case of a young patient with left accessory nerve paralysis is reported. He had slight tilting of the head to the right side, developed over a period of about 6 months. On neurological examination hypotrophy of the left sternocleidomastoid and trapezius muscles was observed. MRI and MR-angiography imaged the presence of a neurovascular compression between the medulla oblungata, at the level of the nerve entry zone, and a vessel loop of an elongated left vertebral artery. In spite of the absence of a surgical demonstration it is our opinion that the neurovascular conflict is the cause of the accessory nerve palsy.

Midline medulloblastoma versus astrocytoma: the position of the superior medullary velum as a sign for diagnosis

PurposeWe wish to describe the position of the superior medullary velum (SMV) in midline posterior fossa tumours as a sign in helping to distinguish between midline medulloblastoma and midline astrocytoma.Material and methodsSagittal T1-weighted MRI images of 21 consecutive patients with histologically documented posterior fossa midline astrocytomas (nine cases) and medulloblastomas (12 cases) were reviewed, with respect to the position of the velum medullare superius.ResultsIn all medulloblastomas the SMV was superiorly dislocated; in eight astrocytomas it was anteriorly and/or inferiorly disclocated; only in one astrocytoma the SMV presented upward dislocation.ConclusionIn the differential diagnosis between medulloblastoma and astrocytoma the upward dislocation of the SMV is strongly suggestive of medulloblastoma.

Gelastic epilepsy without hypothalamic hamartoma: Three additional cases

We describe three children with gelastic seizures without hypothalamic hamartoma whose seizures were characterized by typical laughing attacks associated or not with other seizure types. Ictal/interictal EEG and magnetic resonance imaging were performed. All three subjects showed a good response to carbamazepine therapy with complete seizure control in addition to a benign clinical and cognitive outcome. These three cases confirm that gelastic epilepsy without hypothalamic hamartoma, both in cryptogenic or symptomatic patients (one child showed a dysplastic right parietotemporal lesion), usually has a more benign natural history, and carbamazepine seems to be the most efficacious therapy to obtain both immediate and long-term seizure control. These findings need to be confirmed in a larger sample of children affected by gelastic epilepsy without hypothalamic hamartoma.