Asymmetric Facet Joint Osteoarthritis and Its Relationships to Facet Orientation, Facet Tropism, and Ligamentum Flavum Thickening.

STUDY DESIGN: The degrees of osteoarthritis of the left and right facet joints were evaluated by using computerized tomography among elderly patients with low back or leg pain. OBJECTIVE: To reveal the phenomenon of asymmetry regarding facet joint osteoarthritis (FJOA) in old patients and establish its relationships to spinal level, facet orientation, facet tropism and ligamentum flavum (LF) thickening. SUMMARY OF BACKGROUND DATA: There were few reports regarding left-right asymmetry among severity of FJOA and its relationships to spinal level, facet orientation, facet tropism, and LF thickening remained unclear. METHODS: The grade of bilateral FJOA was evaluated using 4-grade scale on computerized tomography images at the L3-4, L4-5, and L5-S1 levels of patients with age ranging from 60 to 80 years. All subjects were divided into 2 groups: symmetric FJOA group (FJOA I-II on both sides or FJOA III-IV on both sides) and asymmetric FJOA group (FJOA I-II on one side and FJOA III-IV on the other side). The relationships of FJOA to spinal level, facet orientation, facet tropism, and LF hypertrophy were evaluated. RESULTS: No association between asymmetric FJOA and spinal level was noted (P>0.05). In asymmetric FJOA group, significant difference in facet orientation between 2 sides was observed at the L4-5 (P=0.018) and L5-S1 levels (P=0.033). Compared with symmetric FJOA, asymmetric FJOA showed significant difference in prevalence of facet tropism at the L5-S1 level (P<0.001). The LF showed significantly thicker on the side of FJOA III-IV than the side of FJOA I-II at each level in asymmetric FJOA group (P<0.05). However, no difference was found in thickness between 2 sides in symmetric FJOA group (P>0.05). CONCLUSIONS: Asymmetric FJOA is associated with facet orientation and tropism, but not with spinal level. There is a close relationship between severity of FJOA and LF thickness.

[Normal pneumatization time of paranasal sinuses in 799 children: evaluation with magnetic resonance imaging].

OBJECTIVE: To evaluate the onset of initial pneumatization of paranasal sinuses with magnetic resonance imaging (MRI) and provides references in the diagnosis and treatment of pediatric paranasal sinuses disease. METHODS: The MRI images of paranasal sinuses were retrospectively reviewed for 799 children of 0 month to 15 years old and the first pneumatization time of paranasal sinuses were analyzed. RESULTS: The ethmoidal sinuses was the first pneumatized in 100% (46/46) of newborn children. And 45.7% (21/46) of maxillary sinuses showed pneumatization during the first month of life and 97.8% (45/46) were pneumatized at 7 - 12 months. The pneumatized sphenoid sinuses was first identified as early as 4 months. And 86% (43/50) were pneumatized from 1 to 2 years old. Frontal sinuses was the last pneumatized paranasal sinuses. And 8% (4/50) of frontal sinuses were pneumatized at 1 - 2 years old and 97.8% (42/43) showed pneumatization at 14 - 15 years old. CONCLUSION: MRI may be used to observe the pneumatization of paranasal sinuses. The initial pneumatization time of paranasal sinuses is earlier than previously described.

[Neurologic complications in children with enterovirus 71-infected hand-foot-mouth disease : clinical features, MRI findings and follow-up study].

OBJECTIVE: To explore the clinical and magnetic resonance imaging (MRI) characteristics and the follow-up outcomes of neurologic complications in children with enterovirus 71-infected hand-foot-mouth disease. METHODS: The clinical and MRI manifestations and follow-up outcomes in 35 children, at Second Affiliated Hospital, Wenzhou Medical College from August 2008 to November 2010, hospitalized with neurologic complications of enterovirus 71-infected hand-foot-mouth disease were retrospectively analyzed. RESULTS: Six children with aseptic meningitis presented the clinical symptoms and signs of meningitis. Five of them showed subdural effusion and ventriculomegaly, or both on MRI. At follow-ups, neurologic sequel could not be found. Among 24 cases with brainstem encephalitis, there were myoclonic jerks and tremor, ataxia, or both (grade I disease, n = 12), myoclonus and cranial-nerve involvement (grade II disease, n = 4), and cardiopulmonary failure after brain-stem infection (grade III disease, n = 8). In patients with brainstem encephalitis, lesions were predominantly located at the posterior portions of medulla and pons with hypointensity on T1WI and hyperintensity on T2WI. Cerebellar dentate nucleus, caudate nucleus and lenticular nucleus could also be involved. At follow-ups, the patients with mild symptoms had no neurologic sequel and the lesions within brain stem became small or vanished in most cases. While in the majority of serious patients, neurologic sequel could be found and the lesions located at brain stem became encephalomalacia. Fourteen cases with acute flaccid paralysis presented acute limb myasthenia with tendon reflex and muscular tension decreased. On spinal MRI, the lesions predominantly involved anterior horn regions of spinal cord with hypointensity on T1WI and hyperintensity on T2WI. Most patients improved their muscle strength and most lesions of spinal cord became smaller or vanished during follow-ups. CONCLUSION: MRI is the most effective modality of diagnosis and follow-up for neurologic complications in children with enterovirus 71-infected hand-foot-mouth disease. On MRI, the lesions mainly involve the anterior horn of spinal cord, medulla oblongata and pons. At follow-ups, most patients have no neurologic sequel and the visualized lesions will be absorbed after active treatment.