Critical analysis of the Chiari malformation Type I found in children with lipomyelomeningocele

Tubbs RS, Bui CJ, Rice WC, Loukas M, Naftel RP, Holcombe MP, Oakes WJ. Critical analysis of the Chiari malformation Type I found in children with lipomyelomeningocele. Journal of Neurosurgery. 2007 Mar;106(3 Suppl):196-200.

OBJECT: Occasional comments are found in the literature regarding patients with lipomyelomeningocele and concomitant Chiari malformation Type I (CM-I). The object of this study was to explore the association between these two conditions.

METHODS: The authors performed a retrospective database analysis of lipomyelomeningocele cases to identify cases of concomitant CM-I. Analysis of posterior fossa volume (based on the Cavalieri principle) was performed in all identified cases in which appropriate neuroimages were available, and the results were compared with those obtained in age-matched controls. Seven (13%) of 54 patients with lipomyelomeningocele were found to also have CM-I. Two of these were symptomatic (cervicothoracic syrinx and occipital headaches) and required posterior fossa decompression. No correlation was found between the amount of hindbrain herniation and the level of the conus medullaris or the type of lipomyelome-ningocele (for example, caudal or transitional). Volumetric studies of the posterior fossa revealed normal age-matched volumes in all but one patient (who had asymptomatic CM-I).

CONCLUSIONS: The incidence of CM-I in patients with lipomyelomeningocele appears to be significantly greater than that of the general population and the association rate is too high for the finding to be a chance occurrence. Decreases in the volume of the posterior cranial fossa were not found in the majority of patients in this small cohort; therefore, the cause of the concomitant occurrence of lipomyelomeningocele and CM-I remains undetermined. Clinicians should consider obtaining imaging studies of the entire neuraxis in patients with lipomyelomeningoceles and should investigate other causes for syringes found in association with lipomyelomeningoceles.

PMID: 17465384

Predicting orthopedic involvement in patients with lipomyelomeningoceles

Tubbs RS, Winters RG, Naftel RP, Acharya VK, Conklin M, Shoja MM, Loukas M, Oakes WJ. Predicting orthopedic involvement in patients with lipomyelomeningoceles.
Child's Nervous System. 2007 Aug;23(8):835-8. Epub 2007 Mar 27.

INTRODUCTION: Lipomyelomeningoceles (LMM) occur in approximately 1 in every 4,000 live births in the United States. They are associated with a wide range of problems in affected patients, including skin abnormalities, sensory and motor deficits, pain, urinary bladder and anal sphincter dysfunction, and orthopedic deformities.

MATERIALS AND METHODS: In an effort to better understand the orthopedic complications associated with LMM, the present study examined the long-term orthopedic deformities in 50 patients after surgical correction of their LMM and observed for correlation between these deformities and the type and level of LMM.

RESULTS: Analysis of the collected data revealed a statistically significant relationship between of the type of LMM and the presence of orthopedic complications. However, no statistically significant relationship existed between the vertebral level of the LMM and the presence of orthopedic deformities. No correlation was identified between the level and type of LMM.

CONCLUSION: In this study, caudal LMM were much more likely than either dorsal or transitional types to have orthopedic complications. These data may prove useful to clinicians in predicting outcome and in counseling patients and their parents.

PMID: 17387484

Outcome following multiple repeated spinal cord untethering operations.

Maher CO, Goumnerova L, Madsen JR, Proctor M, Scott RM. Outcome following multiple repeated spinal cord untethering operations. Journal of Neurosurgery. 2007 Jun;106(6 Suppl):434-8.

OBJECT: Patients who have undergone prior myelomeningocele or lipomyelomeningocele repair may present with symptomatic retethering of the spinal cord. In some cases, symptomatic tethering may recur after previous untethering operations. The expected outcome following repeated untethering in a patient after two or more prior untethering operations is not well described.

METHODS: The authors examined surgical indications, techniques, and outcomes for 30 repeated untethering operations in 22 patients who had undergone a previous repair of the primary spinal disorder and at least two subsequent untethering operations. The mean age at repeated untethering was 12.3 years. Presenting symptoms were pain (70%), weakness (70%), urinary symptoms (57%), and sensory changes (27%). The mean duration of symptoms was 7.5 months, and a longer symptomatic interval correlated with an increased number of prior operations. Total circumferential untethering was accomplished in 11 cases (37%). Postoperative symptomatic improvement was noted most often for pain (81%), and less often for urinary symptoms (53%) and weakness (48%). Complications included postoperative cerebrospinal fluid leakage or pseudomeningocele and new postoperative lower-extremity dysesthesia in five cases (17%). An increasing number of prior untethering operations was associated with a worse result for pain relief and a greater chance of significant morbidity.

CONCLUSIONS: Multiple repeated untethering operations offer symptomatic relief to well-selected patients with this condition.

PMID: 17566398