This is a T2 MRI L spine demonstrating a sacral myelomeningocele. Meningoceles are congenital cystic dilations of the meninges that herniate through posterior column defects. They are due to a failure of disjunction in which a midline cutaneous defect forms over the neural placode during embryological development, connecting neuroectoderm with ectoderm. Myelomeningoceles involve herniation of neural tissue in addition to herniation of the meninges. 90% of patients presenting with myelomeningoceles also have hydrocephalus. Chiari II malformations, trisomy 18, trisomy 13, diastematomyelia, syringomyelia, arachnoid cysts and tethered spinal cord are also commonly associated. Myelomeningoceles should be repaired immediately after birth to reduce life-threatening risks of infection and meningitis.
This is a T1 MRI brain demonstrating porencephaly, or encephalomalacia resulting in a cyst in the cerebral hemisphere. Porencephaly typically results from ischemic insults to a fetal or neonatal brain. Lined with gliotic white matter, the cysts often develop adjacent to the sylvian fissures or central sulci. Patients with porencephaly often present with cognitive delay, congenital hemiplegia, chronic spasticity and/or epilepsy.
This is an example of arachnoiditis, or adherence of the lumbar nerve roots to the thecal sac. There are two primary etiologies of spinal arachnoiditis: infection and inflammation. Some patients have a history of spinal meningitis, others a history of prior spine surgery, intrathecal drug delivery or intrathecal hemorrhage. Patients can experience leg pain, sensory changes or motor weakness. When assessing for arachnoiditis, look for I) clumping or distortion of the lumbar nerve roots, 2) nerve roots adherent to the thecal sac resulting in an “empty thecal sac sign”, 3) nerve roots and thecal sac clumped together centrally within the spinal canal. Presently, there is no good treatment for arachnoiditis. Intrathecal drug pumps may help with pain.
This is a coronal CT demonstrating a left occipital condyle fracture. Condyle fractures usually occur from high energy, non-penetrating trauma to the head and neck. Of patients presenting with an occipital condyle fracture, approximately 63% will have other neurological deficits, usually involving CNs IX, X, and XI. There are three types of condyle fractures according to the Anderson Montesano Classification: Type I) minimal fragment displacement, Type II) associated with other basilar skull fractures, Type III) avulsion fracture with displacement of fragments.
This is an axial T1 MRI with contrast demonstrating a glomus jugulare tumor growing out of the left jugular foramen. Three cranial nerves traverse the jugular foramen – the glossopharyngeal (CN IX), vagus (CN X) and accessory (CN XI) nerves – and these nerves can be unilaterally affected in the setting of a glomus tumor.
This is a case of lumbar facet arthropathy by Dr. Stephan Ritland, one of my neurosurgeon mentors. Note the hyper intense T2 signal in the facet joints on this axial T2 MRI of the lumbar spine. Follow the link to read about the Ritland submuscular approach for treatment.
This is a CT head demonstrating fibrous dysplasia of the skull base. Fibrous dysplasia is a non-malignant tumor-like congenital process, characterized by replacement of normal bone with fibrous stroma and immature woven bone.
This is a T2 MRI C spine demonstrating a “swan neck deformity” – draping of the spinal cord over a kyphotic deformity of the cervical spine. Typically, extensive cervical fusion is required for correction and prevention of deterioration in symptomatic patients.
This is a CT head demonstrating agenesis, or absence, of the corpus callosum. The corpus callosum is a broad band of axons interconnecting the two hemispheres of the brain. Agenesis of the corpus callosum, although rare, is one of the most common brain malformations in human beings. It can be completely asymptomatic, or it can be associated with autism, seizures, and motor, auditory and/or speech symptoms. The anterior corpus callosum has been noted to be more pronounced in musicians and left handed and ambidextrous people.