Nagamatsu Masakazu, Maste Praful, Tanaka Masato, Fujiwara Yoshihiro, Arataki Shinya, Yamauchi Taro, Takeshita Yoshiyuki, Takamoto Rika, Torigoe Tsukasa, Tanaka Masato, Tanaka Ryosuke, Moriue Shinsuke
Department of Radiology, Okayama Rosai Hospital, 1-10-25 Chikkomidorimachi, Minami Ward Okayama, Okayama 702-8055, Japan.
Department of Orthopaedic Surgery, Okayama Rosai Hospital, 1-10-25 Chikkomidorimachi, Minami Ward Okayama, Okayama 702-8055, Japan.
Diagnostics (Basel). 2022 Apr 12;12(4):956. doi: 10.3390/diagnostics12040956.
Study design: Prospective study. Objective: The aim of this study is to visualize the morphology of a lumbar herniated disc and Kambin’s triangle in three dimensions (3D) based on preoperative CT/MRI fusion images. Methods: CT/MRI fusion images of 23 patients (10 males and 13 females; mean age 58.2 years) were used to evaluate Kambin’s triangle, which is created between the superior articular process (SAP), exiting nerve root (ENR), inferiorly by the superior endplate of the lower lumbar vertebra and dural canal medially at 60 degree and 45 degree endoscopic approach angles. The percentage of the safe usage of transforaminal endoscopic approach was evaluated to utilize a 5 mm dilater without partial facet resection in the fusion image. The 3D lumbar nerve root sleeve angulation (3DNRA), which is the angle between the axis of the thecal sac and the nerve root sleeve, was calculated. The herniated discs were also visualized in the CT/MRI fusion image. Results: The 3DNRA became smaller from L2 to S1. The L2 3DNRA was statistically larger than those of the other root, and the S1 3DNRA was significantly smaller than the others (p < 0.05). (L2, 41.0°; L3, 35.6°; L4, 36.4°; L5, 33.9°; and S1, 23.2°). The SAP-ENR distance at 60° was greatest at L4/5 (5.9 mm). Possible needle passages at 60° to each disc level were 89.1% at L2/3, 87.0% at L3/4 and 84.8% at L4/5. However, the safe 5 mm dilater passage at 60° without bony resection to each disc level were 8.7% at L2/3, 28.3% at L3/4 and 37.0% at L4/5. The 60° corridor at L2/3 was the narrowest (p < 0.01). All herniated discs were visualized in the fusion image and the root compression site was clearly demonstrated especially with foraminal/extraforaminal herniations. Conclusion: The 3D lumbar CT/MRI fusion image enabled a combined nerve-bony assessment of Kambin’s triangle and herniated disc. A fully endoscopic 5 mm dilater may retract the exiting nerve root in more than 60% of total cases. This new imaging technique could prove to be very useful for the safety of endoscopic lumbar disc surgery.
前瞻性研究。目的：本研究旨在基于术前CT/MRI融合图像对腰椎间盘突出症和坎宾三角进行三维（3D）形态可视化。方法：使用23例患者（10例男性和13例女性；平均年龄58.2岁）的CT/MRI融合图像评估坎宾三角，该三角由上关节突（SAP）、穿出神经根（ENR）构成，下界为下腰椎椎体的上终板，内侧为硬膜囊，在内镜入路角度为60度和45度时进行评估。在融合图像中评估经椎间孔内镜入路安全使用5mm扩张器且不进行部分关节突切除的百分比。计算3D腰神经根袖套角（3DNRA），即硬膜囊轴线与神经根袖套之间的角度。还在CT/MRI融合图像中观察突出的椎间盘。结果：3DNRA从L2到S1逐渐变小。L2的3DNRA在统计学上大于其他节段的神经根，而S1的3DNRA显著小于其他节段（p<0.05）。（L2为41.0°；L3为35.6°；L4为36.4°；L5为33.9°；S1为23.2°）。60°时SAP-ENR距离在L4/5处最大（5.9mm）。各椎间盘节段在60°时可能的穿刺路径在L2/3为89.1%，在L3/4为87.0%，在L4/5为84.8%。然而，在60°时不进行骨质切除的安全5mm扩张器通过各椎间盘节段的比例在L2/3为8.7%，在L3/4为28.3%，在L4/5为37.0%。L2/3处60°的通道最窄（p<0.01）。所有突出的椎间盘在融合图像中均可见，尤其是椎间孔/孔外突出时，神经根受压部位清晰显示。结论：3D腰椎CT/MRI融合图像能够对坎宾三角和突出的椎间盘进行神经-骨质联合评估。全内镜5mm扩张器在超过60%的病例中可能会使穿出神经根回缩。这种新的成像技术可能被证明对内镜下腰椎间盘手术安全性非常有用。
