From the Guidelines
The diagnosis of Arnold Chiari malformation (ACM) is typically made using a noncontrast MRI scan of the brain, including a sagittal T2-weighted sequence of the cranio-cervical junction, and treatment depends on symptom severity, with mild cases requiring monitoring and more severe cases needing decompression surgery 1.
Diagnosis
The diagnosis of ACM is crucial in determining the appropriate treatment plan. A noncontrast MRI scan of the brain is the imaging modality of choice, particularly in patients with high suspicion for Chiari I deformity 1. The MRI scan should include a sagittal T2-weighted sequence of the cranio-cervical junction, which can help identify the herniation of the cerebellar tonsils through the foramen magnum.
Symptoms
Symptoms of ACM can include headaches that worsen with coughing or straining, neck pain, balance problems, dizziness, swallowing difficulties, and numbness in extremities 1. In children, symptoms can also include abnormal oropharyngeal function, scoliosis, and headache worsened by the Valsalva maneuver.
Treatment
Treatment of ACM depends on symptom severity. Mild cases may only require monitoring, while more severe cases may need decompression surgery to create more space at the base of the skull and relieve pressure 1. Pain management often includes medications like acetaminophen, NSAIDs, or in some cases, muscle relaxants or nerve pain medications like gabapentin. Physical therapy can help with associated muscle weakness or coordination issues.
Importance of Early Intervention
Early intervention is crucial in the management of ACM, particularly in patients with scoliosis and risk factors 1. A study by Krieger et al found that early intervention was important in preventing the progression of scoliosis and reducing the size of syringes.
Key Points
- ACM is a structural abnormality where brain tissue extends into the spinal canal
- Diagnosis is typically made using a noncontrast MRI scan of the brain
- Treatment depends on symptom severity, with mild cases requiring monitoring and more severe cases needing decompression surgery
- Early intervention is crucial in preventing the progression of scoliosis and reducing the size of syringes
- Patients should seek medical attention if experiencing persistent headaches, progressive neurological symptoms, or if diagnosed but symptoms worsen 1
From the Research
Diagnosis of Arnold Chiari Malformation
- The diagnosis of Arnold Chiari malformation (ACM) involves the identification of a downward displacement of the hindbrain and herniation of the cerebellar vermis, tonsils, pons, medulla, and fourth ventricle through the foramen magnum 2.
- Approximately 95 percent of infants with ACM also present with an associated myelomeningocele (MMC), the most severe form of spina bifida 2.
Treatment of Arnold Chiari Malformation
- Surgery for symptomatic Arnold-Chiari malformation type I involves posterior fossa decompression, with various approaches including endoscope-assisted ones 3.
- Posterior fossa decompression combined with resection of the cerebellomedullary fissure membrane and expansile duraplasty is a radical and rational surgical treatment for Arnold-Chiari type I malformation 4.
- The optimal surgical treatment of Chiari malformation is unclear, but posterior fossa decompression, C1 laminectomy, and duraplasty may lead to a more reliable reduction in the volume of concomitant hydromyelia 5.
- Posterior fossa decompression plus duraplasty is a safe and effective procedure for patients with CM-I malformation 6.
- Fully endoscopic surgery can be successfully performed in patients with Chiari malformation I, with intraoperative neuromonitoring and neuronavigation increasing safety during the procedure 3.