Temporal Lobe Malformations in Achondroplasia: Expanding the Brain Imaging Phenotype Associated with FGFR3-Related Skeletal Dysplasias.

Thanatophoric dysplasia, achondroplasia, and hypochondroplasia belong to the fibroblast growth factor receptor 3 (FGFR3) group of genetic skeletal disorders. Temporal lobe abnormalities have been documented in thanatophoric dysplasia and hypochondroplasia, and in 1 case of achondroplasia. We retrospectively identified 13 children with achondroplasia who underwent MR imaging of the brain between 2002 and 2015. All children demonstrated a deep transverse temporal sulcus on MR imaging. Further common neuroimaging findings were incomplete hippocampal rotation (12 children), oversulcation of the mesial temporal lobe (11 children), loss of gray-white matter differentiation of the mesial temporal lobe (5 children), and a triangular shape of the temporal horn (6 children). These appearances are very similar to those described in hypochondroplasia, strengthening the association of temporal lobe malformations in FGFR3-associated skeletal dysplasias.

Bilateral posterior periventricular nodular heterotopia: a recognizable cortical malformation with a spectrum of associated brain abnormalities.

BACKGROUND AND PURPOSE: Bilateral posterior PNH is a distinctive complex malformation with imaging features distinguishing it from classic bilateral PNH associated with FLNA mutations. The purpose of this study was to define the imaging features of posterior bilateral periventricular nodular heterotopia and to determine whether associated brain malformations suggest specific subcategories. MATERIALS AND METHODS: We identified a cohort of 50 patients (31 females; mean age, 13 years) with bilateral posterior PNH and systematically reviewed and documented associated MR imaging abnormalities. Patients were negative for mutations of FLNA. RESULTS: Nodules were often noncontiguous (n = 28) and asymmetric (n = 31). All except 1 patient showed associated developmental brain abnormalities involving a spectrum of posterior structures. A range of posterior fossa abnormalities affected the cerebellum, including cerebellar malformations and posterior fossa cysts (n = 38). Corpus callosum abnormalities (n = 40) ranged from mild dysplasia to agenesis. Posterior white matter volume was decreased (n = 22), and colpocephaly was frequent (n = 26). Most (n = 40) had associated cortical abnormalities ranging from minor to major (polymicrogyria), typically located in the cortex overlying the PNH. Abnormal Sylvian fissure morphology was common (n = 27), and hippocampal abnormalities were frequent (n = 37). Four family cases were identified-2 with concordant malformation patterns and 2 with discordant malformation patterns. CONCLUSIONS: The associations of bilateral posterior PNH encompass a range of abnormalities involving brain structures inferior to the Sylvian fissures. We were unable to identify specific subgroups and therefore conceptualize bilateral posterior PNH as a continuum of infrasylvian malformations involving the posterior cerebral and hindbrain structures.

Challenges of the anatomy and diffusion tensor tractography of the Meyer loop.

This review addresses the complex and often controversial anatomy of the anterior bundle of the OR, also known as the Meyer loop. Before the advent of MR imaging, 2 main types of studies attempted to ascertain the "safe" distance for anterior temporal lobe resection to avoid postsurgical VFDs. There were those based first on postoperative VFD correlation and second on anatomic dissection studies. In the past decade, noninvasive diffusion MR imaging-based tractography techniques have been developed in an attempt to elucidate white matter connectivity. Although many of these techniques are still experimental, there are some clinical situations for which they may prove to be very helpful if properly performed and validated. The motivation for this review was to improve the outcome of patients with TLE undergoing temporal lobectomy: Would having anatomic information about the OR available to the neurosurgeon decrease the risk of postsurgical VFDs?

Menkes disease: a rare cause of bilateral inguinal hernias.

This case of Menkes disease presented with the uncommon association of bilateral inguinal hernias at the age of 4 months. Further investigation demonstrated classical skeletal and neurological changes of this rare neurodegenerative disorder.

Complementary use of radiological skeletal survey and bone scintigraphy in detection of bony injuries in suspected child abuse.

AIM: To compare the effectiveness of radiological skeletal survey and bone scintigraphy for the detection of bony injuries in cases of suspected child abuse. METHODS: All cases with a discharge diagnosis of child abuse that presented to the Royal Children's Hospital between 1989 and 1998 were retrieved, and those children that had undergone both skeletal survey and bone scintigraphy (radioisotope bone scan) within a 48 hour period were included in this study. Both examinations followed rigid departmental protocols and protocols remained identical throughout the timeframe of the study. The reports of the skeletal surveys and bone scans were retrospectively reviewed by a paediatric radiology fellow and consultant paediatric radiologist. RESULTS: The total number of bony injuries identified was 124 in 30 children. Of these, 64 were identified on bone scan and 77 on skeletal survey. Rib fractures represented 60/124 (48%) of the bony injuries and were present in 16/30 children (53%), of which 62.5% had multiple rib fractures. Excluding rib fractures, there were 64 (52%) bony injuries, of which 33% were seen on both imaging modalities, 44% were seen on skeletal survey only, and 25% were seen on bone scans alone. Metaphyseal lesions typical of child abuse were present in 20 cases (31%) on skeletal survey; only 35% of these were identified on bone scan. Six children (20%) had normal skeletal surveys, with abnormalities shown on bone scan. There were three children (10%) with normal bone scans who were shown to have injuries radiographically. CONCLUSIONS: Skeletal survey and bone scintigraphy are complementary studies in the evaluation of non-accidental injury, and should both be performed in cases of suspected child abuse.