Percutaneous full endoscopic foraminotomy for treatment of cervical spinal nerve compression in horses using a uniportal approach: Feasibility study.

BACKGROUND: Cervical spinal nerve insult can be a sequel of osteoarthropathy in horses due to enlargement of the articular processes (AP). OBJECTIVES: To describe the percutaneous endoscopic cervical foraminotomy procedure in horses. STUDY DESIGN: Ex vivo experimental study and clinical case report. METHODS: The technique was performed in three equine cadavers and in two clinical cases with history of forelimb lameness located in the caudal cervical region. Briefly, the horse was positioned in lateral recumbency, with the affected AP joint uppermost. Under fluoroscopic guidance, the endoscopic instruments (Ø 6.9 mm, length 207 mm, 25° angle of vision) were positioned at the dorsal bony margin of the intervertebral foramen (IVF). The bone was freed from soft tissues and removed using diamond various burrs, hence widening the IVF. The bone drilling was continued until the medial cortical surface of the caudal AP was removed. Thereafter, the endoscope was removed and the skin portal was closed. RESULTS: The average of operation time in clinical cases was 98 ± 24 min. The horses recovered smoothly from the operation. At 12-month follow-up, the clinical signs had resolved completely without recurrence. MAIN LIMITATION: Small number of clinical cases and absence of post-mortem examination or histopathology performed in the cadaver study to assess possible iatrogenic injuries. CONCLUSION: Cervical spinal nerve decompression via minimal invasive foraminotomy is feasible in horses. More research is required before this procedure can be recommended in clinical cases.

AOSpine Consensus Paper on Nomenclature for Working-Channel Endoscopic Spinal Procedures.

STUDY DESIGN: International consensus paper on a unified nomenclature for full-endoscopic spine surgery. OBJECTIVES: Minimally invasive endoscopic spinal procedures have undergone rapid development during the past decade. Evolution of working-channel endoscopes and surgical instruments as well as innovation in surgical techniques have expanded the types of spinal pathology that can be addressed. However, there is in the literature a heterogeneous nomenclature defining approach corridors and procedures, and this lack of common language has hampered communication between endoscopic spine surgeons, patients, hospitals, and insurance providers. METHODS: The current report summarizes the nomenclature reported for working-channel endoscopic procedures that address cervical, thoracic, and lumbar spinal pathology. RESULTS: We propose a uniform system that defines the working-channel endoscope (full-endoscopic), approach corridor (anterior, posterior, interlaminar, transforaminal), spinal segment (cervical, thoracic, lumbar), and procedure performed (eg, discectomy, foraminotomy). We suggest the following nomenclature for the most common full-endoscopic procedures: posterior endoscopic cervical foraminotomy (PECF), transforaminal endoscopic thoracic discectomy (TETD), transforaminal endoscopic lumbar discectomy (TELD), transforaminal lumbar foraminotomy (TELF), interlaminar endoscopic lumbar discectomy (IELD), interlaminar endoscopic lateral recess decompression (IE-LRD), and lumbar endoscopic unilateral laminotomy for bilateral decompression (LE-ULBD). CONCLUSIONS: We believe that it is critical to delineate a consensus nomenclature to facilitate uniformity of working-channel endoscopic procedures within academic scholarship. This will hopefully facilitate development, standardization of procedures, teaching, and widespread acceptance of full-endoscopic spinal procedures.

Introduction: ECOC 2012 in Amsterdam.

We introduce the Optics Express special issue from the 38th European Conference on Optical Communication and Exhibition (ECOC). A total of 134 expanded papers from ECOC 2012 are included in this special issue.

Direct writing of microlenses in polycarbonate with excimer laser ablation.

A method for fabricating microlenses in polycarbonate material is reported. Using a direct-write technique based on scanning excimer laser ablation with a circular beam, we can etch an arbitrary shape in the polymer material. The beam is obtained by imaging a circular aperture onto the polymer surface, and scanning is realized by the translation stage carrying the sample, which makes successive contours with well-chosen diameters and scan velocities. Afterward, to smooth the ablated surface and release it from debris, a large beam aperture covering the full lens area is used to ablate the lens deeper into the substrate. The fabrication process and the characterization method are described, including calculation of the contour set for a desired lens shape. The optical performance is evaluated by Mach-Zehnder interferometry, showing that aberrations below lambda/10 are possible for slow lenses.