Biportal endoscopic spine surgery, known in the surgical literature as unilateral biportal endoscopy (UBE) and often abbreviated BESS, is a minimally invasive technique that treats disc herniations, spinal stenosis, and nerve compression through two incisions of about 7 to 10 millimeters. One portal carries a high-definition endoscope; the other carries standard surgical instruments. Dr. Erick Kazarian performs biportal endoscopic spine surgery at NYU Langone Health in New York City and is the lead author of a peer-reviewed technical primer on the technique published in The Spine Journal. He is an invited AAOS lecturer on the biportal learning curve and serves as an instructor at national training labs where practicing spine surgeons are taught the biportal technique.
One name, three abbreviations
Patients encounter this technique under several names: biportal endoscopic spine surgery, Biportal Endoscopic Spine Surgery (BESS), and unilateral biportal endoscopy (UBE). All three describe the same operation. “Unilateral” means both portals enter from one side of the spine; “biportal” means there are two of them. The technique was refined in South Korea over the past two decades and is now one of the fastest-growing approaches in minimally invasive spine surgery worldwide.
How the two portals work
Through the first portal, a high-definition endoscope streams a magnified view of the spine to a monitor. Continuous sterile saline irrigation flows through the field, keeping the view clear, gently expanding the working space, and reducing bleeding.
Through the second portal, Dr. Kazarian works with standard spine instruments: the same burrs, ronguers, and probes used in open surgery, but introduced through an opening smaller than a dime. Because the camera and instruments move independently, the technique preserves the triangulation and freedom of movement surgeons rely on in traditional surgery.
The muscles of the spine are not cut or stripped from bone. The portals pass through natural muscle planes, which is the main reason patients typically go home the same day and measure recovery in weeks rather than months.
Conditions treated with BESS
Lumbar disc herniation & sciatica
Removal of the herniated fragment compressing the nerve root, most often via endoscopic microdiscectomy.
Spinal stenosis
Endoscopic laminectomy and decompression to relieve pressure from thickened ligament and bone spurs.
Cervical radiculopathy
Posterior cervical endoscopic decompression for pinched nerves in the neck causing arm pain.
Spondylolisthesis & instability
Endoscopic TLIF combines biportal decompression with fusion in appropriately selected patients.
Biportal vs. uniportal endoscopic surgery
| Biportal (BESS / UBE) | Uniportal | |
|---|---|---|
| Portals | Two: one for the camera, one for instruments | One: camera and instruments share a single channel |
| Instruments | Standard spine instruments move freely, independent of the camera | Limited to specialized instruments that fit the single channel |
| Field of view | Camera angle and instrument angle adjust independently | Camera and instruments locked to the same axis |
| Versatility | Decompression, discectomy, and interbody fusion (endoscopic TLIF) | Best established for discectomy and focal decompression |
Both are legitimate endoscopic techniques. Dr. Kazarian specializes in the biportal approach for its instrument freedom and its extension to fusion procedures.
Biportal vs. microscopic surgery
| Biportal (BESS / UBE) | Microscopic (tubular) | |
|---|---|---|
| Visualization | High-definition camera inside the spine, with continuous saline irrigation keeping the view clear | Microscope outside the body looking down a tubular retractor |
| Incisions | Two incisions of about 7 to 10 mm | One incision of roughly an inch |
| Muscle handling | Muscles gently dilated through natural planes | Muscle retracted through a tube; more disruption than biportal |
| Typical recovery | Same-day discharge; desk work often in 1 to 2 weeks | Same day or overnight; desk work often in 2 to 4 weeks |
Typical ranges for appropriately selected patients, not guarantees. The right technique depends on your diagnosis and anatomy.
Candidacy and limitations
The biportal technique treats many of the most common degenerative spine problems, but it is not the right operation for everyone. High-grade instability or deformity requiring multi-level correction, tumors, active infection, and fractures needing stabilization across several levels are generally treated with other approaches. Symptoms driven by a compressed nerve, such as leg or arm pain, respond best. See the full candidacy guide for details, or bring your MRI to a consultation; Dr. Kazarian reviews every patient's imaging personally.
Training, research, and publication
Dr. Kazarian completed his orthopedic surgery residency in the Harvard Combined Orthopaedic Residency Program at Massachusetts General Hospital and his spine surgery fellowship at the Mayo Clinic. He is an active member of the Endoscopic Spine Surgery Program at NYU Langone Health and the lead author of “Primer on Unilateral Biportal Endoscopic Spine Surgery: Technical Overview for Beginners” (The Spine Journal, 2025), a peer-reviewed technical primer written to help surgeons adopt the biportal technique safely. His full academic work is listed on the research page.
Biportal procedures Dr. Kazarian performs
Endoscopic Microdiscectomy
Endoscopic spine surgery is among the least invasive ways to address disc herniations and spinal stenosis in the lumbar spine.
Posterior Cervical Endoscopic Decompression
A motion-preserving endoscopic procedure that relieves pressure on a pinched nerve in the neck through two small incisions, without fusion or implants.
Endoscopic TLIF
A next-generation lumbar fusion that combines the structural goals of a traditional TLIF with the tissue-sparing advantages of endoscopic surgery.
Biportal endoscopic surgery FAQ
Are BESS, UBE, and biportal endoscopic spine surgery the same thing?
Yes. Biportal Endoscopic Spine Surgery (BESS) and unilateral biportal endoscopy (UBE) are two names for the same technique: endoscopic spine surgery performed through two small portals on one side of the spine, one carrying a high-definition camera and the other carrying surgical instruments.
How is biportal endoscopic surgery different from regular endoscopic surgery?
Most 'regular' endoscopic spine surgery is uniportal: the camera and instruments share a single channel. The biportal technique separates them into two portals, which lets the surgeon use standard spine instruments with the freedom of movement of traditional surgery while keeping incisions under a centimeter.
What conditions can be treated with the biportal technique?
Common indications include lumbar disc herniations and sciatica, spinal stenosis, bone spurs and thickened ligament compressing nerves, cervical radiculopathy treated from the back of the neck, and selected patients who need fusion via endoscopic TLIF.
Is biportal endoscopic surgery as effective as open or microscopic surgery?
For appropriately selected patients, published studies report that biportal endoscopic decompression achieves nerve-decompression results comparable to open and microscopic techniques, with less blood loss, shorter hospital stays, and faster early recovery.
Who performs biportal endoscopic spine surgery in New York City?
Dr. Erick Kazarian performs biportal endoscopic spine surgery at NYU Langone Health in New York City. He is the lead author of a peer-reviewed technical primer on unilateral biportal endoscopic spine surgery published in The Spine Journal and is an active member of NYU Langone's Endoscopic Spine Surgery Program.
How do I find out if I am a candidate?
Candidacy depends on your symptoms, anatomy, and imaging. Dr. Kazarian reviews every patient's MRI personally. Start with the candidacy guide on this site or book a consultation at one of his three New York area offices.
This page is for general education and is not medical advice. Reviewed by Erick R. Kazarian, MD.