Step-by-Step Description of Percutaneous Full-Endoscopic C2 Ganglionectomy: An Anatomic Feasibility Study in Human Cadavers.

BACKGROUND AND OBJECTIVES: The percutaneous full-endoscopic C2 ganglionectomy (PEC2G), an innovative procedure developed for the surgical treatment of intractable occipital neuralgia, was firstly reported by us in 2021. However, a universally accepted and well-articulated protocol modality remains elusive. The primary objective of this anatomic investigation was to meticulously elucidate the standard procedural steps of PEC2G and assess the anatomic features supporting the safe implementation of PEC2G. METHODS: Eighteen fresh adult cadavers were incorporated into this study. From this sample, 3 cadavers were subjected to bilateral PEC2G. Each procedure was documented and assessed, leading to the formulation of standard procedure criteria for PEC2G. Subsequently, 10 sets of anatomic parameters pertinent to this procedure were identified, quantified, and analyzed in 15 cadavers after complete bilateral endoscopic exposure of the C2 ganglion. An assessment of the technical feasibility and potential constraints associated with PEC2G was conducted, providing invaluable insights into the procedure's anatomic considerations. RESULTS: All 3 cadavers successfully underwent the PEC2G without any observed complications, such as dura tears or vertebral artery injuries. The C2 inferior articular process emerged as the optimal bony target for puncture, with the C2 pedicle serving as the standard guiding landmark en route to the C2 ganglion. In the 15 cadavers subjected to the planned procedure, 10 sets of anatomic parameters were quantified, establishing a foundational understanding of the anatomy in the context of PEC2G procedure. The results demonstrated that the characteristic of anatomic data pertinent to surgical site supported the safe implementation of PEC2G. CONCLUSION: This study contributes the standard surgical steps and crucial anatomic parameters relevant to PEC2G. The characteristic of anatomic data bolsters the safety credentials of this technique, which offers a reliable approach to achieve C2 ganglionectomy. These insights undeniably establish a robust foundation for the ongoing refinement and broader adoption of PEC2G.

Percutaneous Endoscope-assisted Visualized Implantation of Puncture Cylindrical Electrodes for Spinal Cord Stimulation: A Cadaveric Feasibility Study.

BACKGROUND: Spinal cord stimulation is an established technique wherein diverse electrode types are strategically implanted within the spinal epidural space for neuromodulation. Traditional percutaneous puncture cylindrical electrodes (PEs) are predominantly implanted by interventionalists utilizing a percutaneous technique under the monitor of radiation, which is a nonvisualized procedure. OBJECTIVE: Our study aimed to assess the feasibility of percutaneous endoscope-assisted visualized implantation approach for PEs, delineating its specific merits and demerits compared to the traditional method. STUDY DESIGN: Laboratory study with Institutional Review Board Number B2023-056SETTING: Clinical Anatomy Research Center, Fudan University. METHODS: Eight freshly procured adult cadavers (4 women and 4 men) were operated on in this study. They were divided into either Group A or Group B, each encompassing 4 cadavers. Group A was subjected to endoscope-assisted PEs implantation, whereas Group B followed the conventional PEs implantation route.In both groups the operative time of introducer needles placement (OTNP), total operative time (TOT), fluoroscopy time of introducer needles placement (FTNP), and total fluoroscopy time (TFT) were documented and analyzed. Furthermore, the precise positioning of the PEs and any ensuing complications were systematically examined. RESULTS: Both Group A and Group B successfully executed all predetermined surgical steps. A total of 16 PEs were implanted (dual electrodes in each cadaver): 8 using the percutaneous endoscope-assisted visualized approach (Group A) and 8 via the traditional methodology (Group B). Group A's mean ± SD durations for OTNP, TOT, FTNP, and TFT were 10.25 ± 1.03 minutes, 31.63 ± 5.87 minutes, 4.58 ± 1.35 seconds, and 43.73 ± 14.46 seconds, respectively. In contrast, Group B exhibited mean ± SD times of 11.55 ± 2.81 minutes, 44.75 ± 7.85 minutes, 23.53 ± 4.16 seconds, and 66.30 ± 6.35 seconds for the same metrics. No discernible statistical difference in OTNP and TOT emerged between the groups. However, Group A demonstrated reduced durations for both FTNP and TFT compared to Group B. The optimal position of the PEs was verified via fluoroscopy, with no recorded instances of dura rupture. These outcomes suggest that this endoscope-assisted technique neither increases surgical time nor compromises efficacy. Instead, it leads to a marked reduction in fluoroscopic duration relative to the traditional methodology. LIMITATIONS: Anatomical study on a human cadaver, the quantity of cadavers, and the procedure's steep learning curve. CONCLUSION: With the assistance of percutaneous spinal endoscopy, introducer needles can be punctured through the ligamentum flavum at the anticipated interlaminar window locus under direct visualization, improving the convenience of the puncture and reducing fluoroscopic exposure. It is a viable alternative for surgeons from diverse training backgrounds to implant PEs, particularly benefiting those well-versed in endoscopic spine surgery techniques.

Percutaneous Endoscopic Unilateral-Approach Bilateral Decompression for Lumbar Spinal Stenosis.

Lumbar spinal stenosis (LSS) involves the narrowing of the spinal canal due to degenerative changes in the vertebral joints, intervertebral discs, and ligaments. LSS encompasses central canal stenosis (CCS), lateral recess stenosis (LRS), and intervertebral foramen stenosis (IFS). The utilization of lumbar endoscopic unilateral laminotomy for bilateral decompression (LE-ULBD) has gained popularity in the treatment of CCS and LRS. This popularity is attributed to the rapid development of endoscopic instruments and the progress of endoscopic philosophy. In this technical report, a detailed introduction to the steps and key points of LE-ULBD is provided. Simultaneously, a retrospective review of 132 consecutive patients who underwent LE-ULBD for central canal and/or lateral recess stenosis was conducted. The outcomes after more than two years of follow-up were assessed using the visual analogue score (VAS), Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA) scores, and the modified MacNab criteria to evaluate surgical efficacy. All 132 patients underwent LE-ULBD successfully. Among them, 119 patients were rated as "excellent," while 13 patients were rated as "good" based on the modified MacNab criteria during the last follow-up. Incidental dural tears occurred in four cases, but there were no post-operative epidural hematomas or infections. The experience demonstrates that LE-ULBD is a less invasive, effective, and safe approach. It can be considered as an alternative option for treating patients with lumbar central canal stenosis and/or lateral recess stenosis.