The role of unidentified bright objects in the neurocognitive profile of neurofibromatosis type 1 children: a volumetric MRI analysis.

PURPOSE: Cognitive impairment is described in 80% of Neurofibromatosis type 1 (NF1) patients. Brain focal areas of T2w increased signal intensity on MRI, the so-called Unidentified Bright Objects (UBOs) have been hypothesized to be related to cognitive dysfunction, although conflicting results are available in literature. Here, we investigated the possible relation between UBOs' volume, cognitive impairment, and language disability in NF1 patients. MATERIAL AND METHODS: In this retrospective study, clinical and MRI data of 21 NF1 patients (M/F = 12/9; mean age 10.1 ± 4.5) were evaluated. Brain intellectual functioning and language abilities were assessed with specific scales, while the analyzed MRI sequences included axial 2D-T2-weighted and FLAIR sequences. These images were used independently for UBOs segmentation with a semiautomatic approach and obtained volumes were normalized for biparietal diameters to take into account for brain volume. Possible differences in terms of normalized UBOs volumes were probed between cognitively affected and preserved patients, as well as between subjects with or without language impairment. RESULTS: Patients cognitively affected were not different in terms of UBOs volume compared to those preserved (p = 0.35 and p = 0.30, for T2-weighted and FLAIR images, respectively). Similarly, no differences were found between patients with and without language impairment (p = 0.47 and p = 0.40, for the two sequences). CONCLUSIONS: The relation between UBOs and cognition in children with NF1 has been already investigated in literature, although leading to conflicting results. Our study expands the current knowledge, showing a lack of correlation between UBOs volume and both cognitive impairment and language disability in NF1 patients.

Recurrent fibrous solitary tumor of the parotid gland with satellite location: imaging, clinical and histological findings of rare entity.

Fibrous Solitary Tumors are infrequent neoplasms originating from mesenchymal tissues, most commonly arising from the visceral pleura and frequently exhibiting a benign behavior. Extra-pleural localization is unusual and the site of origin of these tumors from the parenchyma of the parotid gland is considered extremely rare. We report the case of a 66-years old woman with non-painful slow-growing left latero-cervical mass, who underwent a gadolinium-enhanced Magnetic Resonance Imaging showing a mass originating from the deep lobe of the parotid gland extending into the retro-pharyngeal space. After a total parotidectomy with tumor excision, a diagnosis of histologically proven fibrous solitary tumor of the parotid gland was made. Two years later, CT scan showed post-operative recurrence and further satellite localization in the neck, distant from the initial mass. We performed a literature review of the published similar cases, in order to clinicopathological and imaging features of this rare entity.