Influence of endothelial nitric oxide synthase T-786C single nucleotide polymorphism on aneurysm size.

OBJECT: Among patients with aneurysms, those with heterozygous (T/C) endothelial nitric oxide synthase (eNOS) T-786C single nucleotide polymorphism (SNP), a mutation reducing endothelial nitric oxide synthesis, are reported to have larger ruptured intracranial aneurysms (IAs) than those with homozygous (C/C or T/T) genotype. The authors tested patients harboring aneurysms for eNOS T-786C SNP in two populations--Japanese and Korean. METHODS: The eNOS T-786C SNP was genotyped through direct sequencing in genomic DNA obtained from 336 Japanese and 191 Korean patients with lAs and 214 Japanese and 191 Korean control volunteers. Differences in genotype frequencies among the various aneurysm sizes were evaluated using the Fisher exact test. There was no significant difference in heterozygous (T/C) eNOS T-786C SNP between aneurysms 5 mm or smaller and those from 6 to 9 mm, and between lesions 5 mm or smaller and those 10 mm or larger in 336 Japanese patients harboring aneurysms--220 with ruptured and 116 with unruptured lesions--and in 191 Korean patients with ruptured aneurysms. CONCLUSION: The eNOS T-786C SNP genotype does not influence the size of aneurysms.

Absence of alpha-1 antitrypsin deficiency alleles (S and Z) in Japanese and Korean patients with aneurysmal subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: A possible association has been proposed for the formation of intracranial aneurysm (IA) and deficiency alleles (S and Z) of the alpha1-antitrypsin (AAT) gene. We extensively screened this gene in Japanese and Korean patients with aneurysmal subarachnoid hemorrhage. METHODS: Seven allelic variants, including S and Z alleles, were genotyped by direct sequencing of genomic DNA obtained from 195 and 189 ruptured IA patients and 195 and 94 controls in Japanese and Koreans, respectively. The haplotype in phase-unknown samples was constructed with the expectation-maximization method. Differences in allelic frequencies between patients and controls were evaluated by Fisher exact test. RESULTS: No significant differences in allelic frequencies were observed at all 7 variants between ruptured IA patients and controls. We could not detect the S and Z alleles of the AAT gene in Japanese and Korean populations. CONCLUSIONS: AAT deficiency may not be a common genetic risk factor for aneurysmal subarachnoid hemorrhage in Japanese and Koreans.

Radiological changes in the bone fusion site after posterior lumbar interbody fusion using carbon cages impacted with laminar bone chips: follow-up study over more than 4 years.

STUDY DESIGN: A retrospective clinical study with a follow-up of more than 4 years was conducted. OBJECTIVES: To know the radiologic changes in the interbody bone fusion site in patients who had received posterior lumbar interbody fusion (PLIF) using carbon fiber cages. SUMMARY OF BACKGROUND DATA: PLIF using cages is a popular surgical method for treating degenerative lumbar spinal diseases. However, there are few reports on the radiologic changes in the bone fusion site after this procedure. METHOD: Forty-one patients were observed (male-to-female ratio 12:29; mean age 51 years; 1-level-to-2-level PLIF 37:4) for 56 months (range 48-78). Anteroposterior and lateral radiograph films were taken from all patients immediately after bone fusion, at 6 and 12 months after surgery, and at follow-up. The extent of the bone fusion was classified as: only inside the cage; around the cage; extending to the vertebral cortical margin; and overgrowth beyond the vertebral cortical margin. The extent of bone fusion was observed anterior and posterior to the cages. RESULTS: Of the 45 fusion levels examined in these 41 patients, successful bone fusion was observed in 40 levels of 36 patients (88%). All the successful fusions occurred inside and posterior to the cages. Of the 40 successful fusion levels at 6 and 12 months after surgery, 10% and 35% of the levels showed the fusion mass to be both inside and around the cages, while the remaining 90% and 65% of the levels showed the fusion mass only inside the cages, respectively. More than 4 years after surgery, 82% of the levels showed the fusion mass extending to the posterior cortical margin, and 2 levels (5%) with shallowly inserted cages showed bony overgrowth into the spinal canal. CONCLUSION: All the intervertebral bone fusion after PLIF occurred inside the cages and in the posterior intervertebral space. We suggest the complete removal of discmaterial and deep insertion of the cages to create sufficient posterior intervertebral space for bone growth. PLIF using cages impacted with laminar bone chips is a useful method when considering the time required for surgery and the morbidity of the autograft donor sites.