Paolo Galluzzi

Guidelines for imaging retinoblastoma: imaging principles and MRI standardization

Retinoblastoma is the most common intraocular tumor in children. The diagnosis is usually established by the ophthalmologist on the basis of fundoscopy and US. Together with US, high-resolution MRI has emerged as an important imaging modality for pretreatment assessment, i.e. for diagnostic confirmation, detection of local tumor extent, detection of associated developmental malformation of the brain and detection of associated intracranial primitive neuroectodermal tumor (trilateral retinoblastoma). Minimum requirements for pretreatment diagnostic evaluation of retinoblastoma or mimicking lesions are presented, based on consensus among members of the European Retinoblastoma Imaging Collaboration (ERIC). The most appropriate techniques for imaging in a child with leukocoria are reviewed. CT is no longer recommended. Implementation of a standardized MRI protocol for retinoblastoma in clinical practice may benefit children worldwide, especially those with hereditary retinoblastoma, since a decreased use of CT reduces the exposure to ionizing radiation.

Hemimegalencephaly in Tuberous Sclerosis Complex

The purpose of this case report is to describe the computed tomographic and magnetic resonance imaging findings of the brain of a 16-month-old girl with an uncommon association between hemimegalencephaly and tuberous sclerosis complex. When a large calcification is found within a hemimegalencephalic cerebral hemisphere, further investigation of a suspected associated tuberous sclerosis complex or another phakomatosis is required to determine pertinent treatment options and genetic counseling. (J Child Neurol 2002;17:677-680).

Superselective ophthalmic artery infusion of melphalan for intraocular retinoblastoma: preliminary results from 140 treatments

Purpose:  To report our experience in superselective ophthalmic artery infusion of melphalan (SOAIM) for intraocular retinoblastoma.

MRI of Wolfram syndrome (DIDMOAD).

Abstract Wolfram syndrome (DIDMOAD) is a rare diffuse neurodegenerative disorder characterised by diabetes insipidus, diabetes mellitus, optic atrophy, deafness, and a wide variety of abnormalities of the central nervous system, urinary tract and endocrine glands. It may be familial or sporadic. Reported features on MRI of the brain are absence of the physiological high signal of the posterior lobe of the pituitary, shrinkage of optic nerves, chiasm and tracts, atrophy of the hypothalamic region, brain stem, cerebellum, and cerebral cortex. We report a 12-year-old girl with a 5-year history without brain stem, cerebellar or cerebral atrophy. MRI showed an unusual feature: a focus of high signal on PD- and T2-weighted images in the right substantia nigra. This is consistent with previously reported neuropathological post-mortem studies, but has never been reported in vivo.

Is CT still useful in the study protocol of retinoblastoma

BACKGROUND AND PURPOSE: Intralesional calcium deposition is considered a key element for differentiating retinoblastoma from simulating lesions. Our aim was to assess whether MR imaging associated with ophthalmologic investigations (ophthalmoscopy and ultrasonography) could replace CT in the detection of diagnostic intralesional calcifications in retinoblastoma. MATERIALS AND METHODS: Ophthalmoscopic findings, MR images, CT scans, and histologic examination of 28 retinoblastomas from 23 consecutive children (11 males, 12 females; age range at admission, 1–35 months; mean age, 11 months; median age, 9 months) were retrospectively evaluated. Ultrasonography was performed in 18 patients with 21 retinoblastomas. MR imaging included T2-weighted spin-echo and gradient-echo images, fluid-attenuated inversion recovery images, and T1-weighted spin-echo images with and without contrast enhancement. Clinical data were integrated with MR imaging data to evaluate the utility of both approaches to discover calcifications; particularly, a correlation between intralesional signal-intensity void spots on MR imaging and hyperattenuating areas on CT scans was performed. RESULTS: Ophthalmoscopy detected calcifications in 12 of 28 eyes (42.85%). Ultrasonography detected calcifications in 20 of 21 eyes (95.23%). CT showed hyperattenuating intralesional areas consistent with calcifications in 27 of 28 eyes (96.42%). MR imaging showed intralesional signal-intensity void spots in 25 of 28 eyes (89.28%). All spots detected with MR imaging matched the presence of calcifications on CT scans. Gradient-echo T2*-weighted and fast spin-echo T2-weighted images showed the highest degree of correlation with CT. When we put together ophthalmoscopy, ultrasonography, and MR imaging data, no calcifications detected on CT were missed, and the differential diagnosis was thorough. CONCLUSIONS: A combination of clinical data and MR images may remove potentially harmful ionizing radiation from the study protocol of retinoblastoma.

Uncommon findings in idiopathic hypertrophic cranial pachymeningitis

Abstract.Background:Idiopathic hypertrophic cranial pachymeningitis (IHCP) is a rare, poorly understood, inflammatory disease, usually involving the dura mater of skull base, tentorium, and falx, and presenting with headache, progressive cranial nerve palsies, and cerebellar dysfunction.Patients and Methods:In four patients, the diagnosis of IHCP has been made on the basis of extensive clinical, and radiological investigation, and confirmed by dural biopsy in three patients. The clinical follow-up ranges from 24 to 120 months.Results :At diagnosis, all the patients complained of severe, progressively increasing headache, two had simple or complex partial seizures, but none had cranial nerve palsies. Two patients had electrophysiological evidence of axonal peripheral neuropathy, biopsy-proved in one of them. In all the patients, MRI showed linear or focal thickening of the dura mater of the tentorium and/or of the convexity, sparing the skull base. In one patient, MRI findings resembled chronic subdural hematoma. Dural biopsy demonstrated fibrosis and prominent CD4+ T-cells inflammatory infiltrate. Pachymeningitis was highly responsive to steroid therapy, as was the peripheral neuropathy. In three patients, temporary steroids withdrawal led to dramatic clinical worsening including status epilepticus in one.Conclusions :In the patients here reported, absence of cranial nerve impairment, seizures, MRI findings resembling chronic subdural hematoma, and association with polineuropathy were unusual findings of IHCP. Moreover, the type of inflammatory infiltrate, lacking in previous reported cases, suggests a probable pathogenetic role for cell-mediated immunity of unknown origin.

Facial hemangioma and malformation of the cortical development: A broadening of the PHACE spectrum or a new entity?

Facial hemangioma is usually isolated but its association with craniocervical arterial anomalies and structural brain malformations is well known. The acronym PHACE syndrome (posterior fossa malformation, facial hemangiomas, arterial anomalies, cardiac/aortic anomalies, and eye abnormalities) has been used to indicate that disorder in which brain anomalies are mainly represented by the Dandy–Walker malformation. We report on a 10‐month‐old boy affected by facial hemangioma and a complex cortical dysplasia located in the left frontal region. The lesion was characterized by a deeply infolding pachygyric cortex and a band of gray matter lining the wall of the lateral ventricle. The entire left cerebral hemisphere appeared hypoplastic. No anomalies of the posterior fossa structures or cardiac/aortic malformations were present. An overlapping clinical/pathological pattern was previously reported in another patient with facial hemangioma and cerebrovascular anomalies. These observations seem to indicate that the facial hemangiomas may be associated with disorders of the cortical development.

Hot water epilepsy and focal malformation of the parietal cortex development

Hot water epilepsy (HWE) refers to a specific type of reflex epilepsy precipitated by the stimulus of bathing in hot water. HWE is considered to be a geographically specific epileptic syndrome since it mainly occurs in the Indian community. Spontaneous seizures may also occur later in life. The seizure pattern includes complex partial attacks. Although the pathogenesis of HWE is still unknown, temporal lobe has been thought to take part in the epileptogenesis. This paper reports on a 4-year-old girl who, at the age of 6 months, experienced complex partial seizures triggered by bathing in hot water. Non-provoked seizures intercritical EEG showed isolated spikes and spike-and-waves in the left parietal region. Brain MRI detected a left parietal focal cortical dysplasia. This is the second patient with HWE in whom a cortical malformation has been observed. The observation present here and data reported in the literature seem to indicate that the sensory cortex might also be involved in triggering seizures precipitated by a bath in hot water. Moreover, the authors believe that MRI examination should be considered for this group of patients.

GM2 gangliosidosis variant B1 neuroradiological findings.

Abstract. Variant B1 is a rare type of GM2 gangliosidosis. Clinically, it shows a wide spectrum of forms ranging from infantile to juvenile. We report the first magnetic resonance imaging (MRI) findings from three patients affected by GM2 gangliosidosis variant B1, two presenting with the infantile form and one with the juvenile form. The MRI appearances of the two patients with the infantile form disease are congruent with those reported for the early-onset type of both Tay-Sachs and Sandhoff diseases, and are characterized by early involvement of the basal ganglia and thalamus with cortical atrophy appearing later. In contrast, the patient with the juvenile form of variant B1 showed progressive cortical and white-matter atrophy of the supratentorial structures and, to a lesser extent, the infratentorial structures. No basal ganglia or thalamic anomalies were observed. Because in the adult forms of both Tay-Sachs and Sandhoff diseases a progressive cerebellar atrophy represents the only abnormality detectable, it appears that an MRI pattern peculiar to GM2 gangliosidosis can be defined. This pattern ranges from the basal ganglia injury associated with the early and severe demyelination process noted in the infantile form of the disease, to cerebellar atrophy with no supratentorial anomalies in the adult form. An “intermediate” MRI picture, with cortical atrophy and mild cerebellar atrophy, but without basal ganglia impairment, can be observed in the juvenile form. In addition, our investigations suggest that MRI abnormalities in GM2 gangliosidosis correlate with the clinical form of the disease rather than with the biochemical variant of the enzymatic defect.

Medial temporal lobe dysgenesis in Muenke syndrome and hypochondroplasia

Hypochondroplasia (HCH) and Muenke syndrome (MS) are caused by mutations on FGFR3 gene. FGFR3 is known to play a role in controlling nervous system development. We describe the clinical and neuroradiological findings of the first two patients, to our knowledge, affected by HCH and MS, respectively, in whom bilateral dysgenesis of the medial temporal lobe structures has been observed. In both patients diagnosis was confirmed by molecular analysis. They were mentally normal and showed similarities in early‐onset temporal lobe‐related seizures. In both patients EEG recorded bilateral temporal region discharges. MRI detected temporal lobe anomalies with inadequate differentiation between white and gray matter, defective gyri, and abnormally shaped hippocampus.