No abstract

The atlantoaxial region has been extensively described as a spinal segment especially prone to injury in children. In this clinical review, the authors evaluate and summarize the management of 23 pediatric cases of atlantoaxial instability treated between March 1990 and October 2002. Four broad categories of atlantoaxial problems were observed—atlantoaxial rotatory subluxation in six patients, anterior–posterior atlantoaxial instability caused by ligamentous injury or congenital ligamentous laxity (10 patients), atlantoaxial fracture with or without dislocation (five patients), and atlantooccipital dislocation (two patients). Most cases (60.9%) were treated without surgical intervention, resulting in excellent outcomes; however, 21.7% of cases were treated with a cervical halo (mean patient age 72.6 months) alone for 3 months. Various techniques of surgical stabilization including transarticular screws with sublaminar wiring, trans-oral decompression with posterior plating, and laminectomy with Steinmann pin occipital–cervical fusion were used with good results. Both patients with atlantooccipital dislocation underwent immediate Locksley occipital–cervical fusion, with marked neurological improvement. Individualized case management must be based on clinical presentation, with internal fixation being the last resort.

To assess objectively the sensitivity and specificity of low-field-strength (0.064 T) magnetic resonance (MR) imaging, a prospective blind study of 280 examinations was performed to compare low-field-strength MR imaging with computed tomography (CT) and with high-field-strength (1.5-T) MR imaging of the cranium. The sensitivity (defined as the true-positive rate) with high-field MR imaging was superior to that with low-field MR imaging and CT in helping detect overall abnormalities. Sensitivities were generally similar over a broad range of specific cranial central nervous system diseases. Low-field and high-field MR imaging were equivalent in the blind diagnoses of neoplasms and white matter disease, whereas low-field MR and CT were equivalent in the blind diagnoses of contusion, subdural and epidural hematoma, sinus disease, normality, and abnormality. The specificities with low-field MR imaging and CT were substantially better than those with high-field MR imaging.

The preliminary results indicate that multiple intraarterial papaverine treatments consistently improve cerebral circulation times, even with repeated infusions in cases of recurrent vasospasm.

The authors describe a method of harvesting autologous pericranium for duraplasty in patients with Chiari malformation Type I (CM-I) that avoids excessive exposure or a second incision. Nonautologous dural grafts have been associated with numerous complications including hemorrhage, bacteria and virus transmission, fatal Creutzfeldt-Jakob disease transmission, foreign body reaction, systemic immune response, excessive scarring, slower healing, premature graft dissolution, and wound dehiscence. Autogenous tissues have the advantage of being nonimmunogenic, nontoxic, readily available, and inexpensive. Pericranium is a preferred substrate because it is flexible, strong, and easily sutured for a watertight closure. Current literature supports the use of autogenous pericranium for dural grafting in CM-I procedures, but has heretofore failed to provide a method of harvest that avoids the complications associated with a larger exposure or second incision. The authors offer a simple alternative technique for using local pericranium in duraplasty for CM-I or other posterior fossa abnormalities.