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  • Innovative Grid Positioning System (GPS) Guidance for Endoscopic Transforaminal Microdecompressive Lumbar Disc Surgery in the Morbid Obese Patient

    Final Number:

    John C. Chiu MD

    Study Design:

    Subject Category:

    Meeting: Congress of Neurological Surgeons 2011 Annual Meeting

    Introduction: Morbid obesity is characterized by an individual having a body mass index (BMI) of 40 or higher. The morbidly obese patient poses many unusual surgical/anatomical challenges during endoscopic minimally invasive spine surgery (MISS), especially to target the lesion with precision and accuracy through a surgical portal of entry. The problem that faces the surgeon performing MISS is that it is done with limited surgical exposure and visualization of the surgical field.

    Methods: In response a logical and simple Grid Positioning System (GPS) was developed to provide a precise surgical trajectory/approach for the disc lesion to undergo decompression. GPS involves 3D geometric triangulation of 3 different planes guided by fluoroscopy for introduction of surgical instruments along a geometric line toward the lesion without compromising healthy anatomical structures. This system facilitates MISS, especially in the morbidly obese. 156 morbidly obese surgical patients with 254 intractable symptomatic herniated lumbar discs underwent endoscopic MISS, guided by GPS.

    Results: Overall result 90% patients with good to excellent results. Fair results 6.4% patients, for single level, average satisfaction score is 93%.

    Conclusions: Applying the concept of Grid Positioning System (GPS) to MISS can help the surgeon to facilitate the MISS process by quickly identifying the surgical portal of entry to the disc without compromising vital anatomical or neural structures and accomplish needed spinal microdecompression, especially in medically high-risk patients including the morbidly obese and even those with prior surgeries. It can be very effective in surgical treatment of degenerative spine and herniated lumbar discs condition.

    Patient Care: Applying the concept of Grid Positioning System to minimally invasive spinal surgery can help the surgeon to facilitate the spinal surgical process by quickly identifying the surgical portal of entry to the disc without compromising vital anatomical or neural structures.

    Learning Objectives: 1. By the conclusion of this session, participants should be able to describe endoscopic transforaminal microdecompressive lumbar disc surgery for morbid obese patients 2. To discuss the definition of a morbid obese patient being 100 lbs over ideal body weight, with a high body mass index (BMI) which significantly increases surgical complications in these patients 3. To identify the effective surgical technique with GPS System (grid positional system)which facilitates the spinal surgery and reduces surgical complications


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