Genes Regulate Purkinje Cell Diversity in Cerebellar Development and Evolution.

Mammalian cerebellar development is thought to be influenced by distinct Purkinje cell (PC) subtypes. However, the degree of PC heterogeneity and the molecular drivers of this diversity have remained unclear, hindering efforts to manipulate PC diversification and assess its role in cerebellar development. Here, we demonstrate the critical role of genes in cerebellar development by regulating PC diversification.

Lumbar facet joint synovial cyst: percutaneous treatment with steroid injections and distention--clinical and imaging follow-up in 12 patients.

Purpose: To determine the imaging characteristics of lumbar facet joint synovial cysts after percutaneous treatment with steroid injections and distention of the cyst and to correlate these findings with the clinical outcome.

Materials And Methods: Clinical outcome and imaging findings were retrospectively studied in 12 patients (four men, eight women) aged 45-79 years (mean, 60 years) with a symptomatic lumbar facet joint synovial cyst treated with percutaneous steroid injections. At varying times after the procedure, patients were contacted for clinical follow-up, and repeat imaging was performed to verify the status of the cyst.

Adductor insertion avulsion syndrome (thigh splints): spectrum of MR imaging features.

Objective: "Thigh splints," also known as the adductor insertion avulsion syndrome, is a painful condition affecting the proximal to mid femur at the insertion of the adductor muscles of the thigh. Scintigraphic findings in this syndrome have been described; we report a spectrum of MR imaging abnormalities involving this portion of the femur in a group of patients presenting with hip, groin, or thigh pain.

Conclusion: Symptoms of vague hip, groin, or thigh pain may be associated with stress-related changes in the proximal to mid femoral shaft (thigh splints).

Arachnoiditis ossificans: MR imaging features in five patients.

Objective: The purpose of this article is to illustrate the appearance of arachnoiditis ossificans on MR imaging and discuss the implications this diagnosis has on treatment.

Conclusion: In patients with arachnoiditis ossificans, the MR imaging findings are of linear or masslike intrathecal lesions, which generally have some hyperintensity on T1- weighted sequences and are hyper- or hypointense on T2-weighted images, in the setting of arachnoiditis.

Pedicle marrow signal intensity changes in the lumbar spine: a manifestation of facet degenerative joint disease.

Objective: Signal intensity changes in lumbar pedicles, similar to those described in vertebral body endplates adjacent to degenerated discs, have been described as an ancillary sign of spondylolysis on MRI. The purpose of this study was to determine whether pedicle marrow signal intensity changes also occur in association with facet degenerative joint disease.

Design: Eighty-nine lumbar spine MRI examinations without spondylolysis were reviewed for marrow signal intensity changes in pedicles and vertebral bodies as well as for facet degenerative joint disease.