Keywords
Minimally invasive surgical procedures - Neuroendoscopy - Spinal cord
Introduction
Endoscopic spine surgery has proved to be a viable alternative to open or microscopic
surgery.[1]
[2] It provides the advantages of minimal invasiveness, panoramic vision, short hospital
stay, and reduced blood loss. Indian surgeons have earned both technical and technological
expertise in this field. These include being involved in the implementation of novel
approaches from craniocervical to the lumbosacral junction, and the development of
new instruments. The endoscopic era started two decades back, and it is still scaling
new heights. This review highlights the rich history of endoscopic spine surgery in
India.
Methodology
A Pubmed search using keywords: “Neuroendoscopy;” “Endoscopic Spine India[ad]”; “Endoscopic
Craniovertebral Junction India[ad]”; “Endoscopic Lumbar disc”; “Endoscopic Cervical
disc”; Endoscopic Thoracic disc”; “Endoscopic spinal neoplasm India[ad]”; “Endoscopic
Chiari malformation India[ad]” was done. It revealed 272 results, of which 53 articles
were found to be relevant. All articles belonged to English literature.
Endoscopic Interlaminar Approach to Lumbar Disc
Endoscopic Interlaminar Approach to Lumbar Disc
The earliest evidence of published endoscopic spine literature from India is by Husain
et al in 2005.[3] They developed a conical tube for the interlaminar approach to herniated lumbar
discs, and showed 90% excellent results at L1-2 to L5-S1 disc levels.[3] Similarly, Ranjan et al published their results of 107 lumbar discs at L4-5 or L5-S1
by introducing the endoscope through the Medtronic tubular system. The success rate
was 92.4% with a 6.5% complication rate.[4] Jhala et al also reported encouraging results.[5] Kaushal et al with a series of 300 patients published the use of the Destandau system
in India, showing good results in 90% of patients.[6] The 2011 randomized controlled trial by Garg et al between microendoscopic and open
lumbar discectomy was the first class 1 evidence for endoscopic spine surgeries from
India. They showed reduced hospital stay and blood loss in the microendoscopic group,
however, the operative time was longer. The improvement was similar in both groups.[2] Yadav et al in 2013 published a series of 400 single or double-level lumbar discectomy
with unilateral or bilateral symptoms of central, sequestrated, or migrated disc using
the Destandau system. They showed 91% good-to-excellent results using the McNab criteria
with a follow-up ranging from 10 months to 5 years.[7]
[8] Later, other authors including Wani et al from Sher-i-Kashmir Institute of Medical
Sciences and other centers also showed excellent outcomes with microendoscopic techniques.[9]
[10]
[11]
[12]
[13]
[14] Innovative methods like the use of a knee-joint arthroscope for lumbar discs by
Kaushal et al and the development of indigenous endoscopic discectomy set: “Endospine
plus” by Chhabra et al have proved useful and reduced the costs of these procedures.[15]
[16]
Endoscopic Approaches to Lumbar Canal Stenosis
Endoscopic Approaches to Lumbar Canal Stenosis
Yadav et al successfully showed endoscopic multilevel decompression of the lumbar
canal after endoscopic decompression, using a unilateral approach. They showed significant
improvement in various canal diameters after surgeries such as anteroposterior diameter
(4.75 ± 1.75 mm to 10.33 ± 2.11 mm), interfacet distance (12.70 ± 4.86 mm to 18.92
± 3.53 mm), and canal surface area (76.45 ± 25.36 mm2 to 187.13 ± 41.04 mm). Of the total, 90% of the patients showed excellent clinical
improvement.[17]
[18]
Endoscopic Transforaminal Lumbar Discectomy
Endoscopic Transforaminal Lumbar Discectomy
This technique was pioneered in India by Dr. Gore. He along with Yeung in 2011 showed
in vivo pathoanatomy of intradiscal, foraminal, and central disc herniations by the
transforaminal technique.[19] They further went on to show endoscopic foraminal and dorsal rhizotomy for chronic
axial back pain in 450 patients with good results.[20] Later, they also utilized this technique for failed back surgery syndrome.[21] High-intensity zone lesions in lumbar discs as a pain generator was described by
Gore’s group and reported good results using the transforaminal technique.[22] The technique provided benefits of a natural route, the Kambin’s triangle, and avoiding
the violation of any bony structures (lamina, facets). The ability of this technique
to be performed under local anesthesia was an added advantage.[23] Good results of this technique were also shown by other authors subsequently.[24] Decompression of canal stenosis is difficult and is a critical limitation of this
technique.
Endoscopic Aspiration and Biopsy of Tubercular Lumbar Spondylodiskitis
Endoscopic Aspiration and Biopsy of Tubercular Lumbar Spondylodiskitis
In a series of 18 patients with intractable back pain, Pawar et al used the percutaneous
transforaminal technique for aspiration and biopsy of the lumbar epidural abscess.
The pain scores improved in all the patients and there was no recurrence after chemotherapy.[25]
Thoracoscopic Decompression of Tubercular Spondylitis
Thoracoscopic Decompression of Tubercular Spondylitis
Thoracoscopy is a minimally invasive technique to deal with anterior and middle columns
of dorsal vertebrae pathologies. Kapoor et al, in 2005, achieved good neurologic recovery
by decompressing the tubercular thoracic spine with the help of video-assisted thoracoscopy
in 14 out of 16 patients.[26] The thoracoscopic approach was shown to be a viable alternative to open thoracotomy.
Later, Jayaswal et al combined debridement with fusion in such cases. The anterior
column was reconstructed with either a rib graft or titanium mesh cage.[27] In 2012, Kapoor et al published their long-term follow-up (60–90 months) in 30 patients
with return of neurological functions and ambulatory power in all patients.[28]
Endoscopy for Cervical Disc Disease
Endoscopy for Cervical Disc Disease
Yadav et al introduced this approach in India in 2014. In a prospective series of
50 patients of monosegmental soft or hard disc causing radiculomyelopathy, the pain
scores and Nurick grading were shown to improve with no permanent complication or
mortality.[29] Later, they also published two-level disc surgeries with a technique of disc-preservation.[30] Percutaneous endoscopic cervical discectomy in India was started by Nadkarni et
al. On 20 patients, with a follow-up of 6 months, they reported good pain relief and
favorable functional outcome. It was performed as stitchless day care surgery.[31]
Endoscopic Cervical Corpectomy
Endoscopic Cervical Corpectomy
Endoscopic partial corpectomy was first described by Yadav et al. The procedure aims
to partially remove the vertebral body without the need for fusion, thereby possibly
avoiding the complications of a fusion procedure. The procedure is indicated when
the compressive element is posterior to the body and also when the disc is significantly
migrated behind the vertebral body.[32]
Endoscopic Posterior Approach for Cervical Spondylotic Myelopathy
Endoscopic Posterior Approach for Cervical Spondylotic Myelopathy
The endoscopic approach for cervical spondylotic myelopathy avoids damage of supraspinous
ligaments and preserves one-sided paraspinal musculature. This is critical for reducing
pain and stability. Yadav et al first performed endoscopic hemilaminectomies and laminoforaminotomies
for cervical spondylotic myelopathy in India.[33] In a prospective series of 50 patients, they showed good results with no permanent
complications. The approach is particularly useful for multilevel cervical myelopathy.
Endoscopic Approach for Chiari Malformation
Endoscopic Approach for Chiari Malformation
Ratre et al first published the Indian study of an endoscopic approach for Chiari
I malformation with or without syrinx. Endoscopic suboccipital drilling of approximately
3 cm bone along with laminectomy of atlas and partial splitting of dura showed improvement
in 15 patients. It is a safe and effective alternative to microsurgical management.[34]
Endoscopy for Spinal Tumors
Endoscopy for Spinal Tumors
Endoscopic excision is possible for both intradural and extradural spinal tumors,
although requiring a steep learning curve. Kulkarni et al published a C2 lamina-lateral
mass complex osteoid osteoma operated by microendoscopic technique. The tumor was
removed completely with improvement in pain and neck disability index at a 1-year
follow-up.[35] Parihar et al reported 18 intradural extramedullary tumors of cervical, thoracic,
and lumbar levels using the Destandau system and showed clinical improvement in all
patients. The hemostasis and dural closure required experience.[36] Similarly, Dhandapani et al reported similar outcomes in 16 intradural tumors, including
at craniovertebral junction.[37] Degenerative epidural cysts can also be effectively treated by minimally invasive
endoscopic means.[38]
Endoscopic Approaches for Irreducible Atlantoaxial Dislocation (AAD)
Endoscopic Approaches for Irreducible Atlantoaxial Dislocation (AAD)
The minimal invasiveness of endoscopic surgeries obviates excessive retraction of
critical structures. Endoscopic transoral odontoid excision was first reported in
India by Husain et al in 2006.[39] Yadav et al, in 34 patients of irreducible AAD, showed safety and efficacy of this
technique without palatal splitting, even in patients with small oral openings.[40]
[41]
[42] Later, they described both anterior decompression and fusion using transoral approach
with good outcome.[43] Nagpal published a report of transnasal endoscopic removal of odontoid for severe
basilar invagination.[44] Similar endoscopic transnasal approach was reported by Deopujari et al in 2014.[45] Overall, if the majority of lesion is above the hard palate, one should use transnasal
route, and when it is between the palate and mandible, transoral approach provides
direct trajectory. Yadav et al used combined fusion with decompression in irreducible
AAD cases, utilizing a single-stage transcervical endoscopic approach. In a series
of 10 patients, they showed its safety and good efficacy. A sterile route, compared
with transnasal and transoral, single stage decompression and fusion, and minimal
invasiveness were its advantages.[46]
[47]
Exoscope
Exoscope is a device, which has a long focal length. The device is a bridge between
an endoscope and a microscope and can be used to learn endoscopic skills. It also
adds to the surgeon’s comfort compared with a microscope. Parihar et al used the exoscope
in both cranial and spinal procedures with good outcomes.[48]
Endoscopic Training
As endoscopy has a steep learning curve, one has to learn adequately to avoid complications.
Live operative workshops and cadaver training are invaluable tools for this. A big
impetus to the endoscopic training in India has been given by the neuroendoscopy fellowship
program by Prof. YR Yadav. It has trained more than 600 surgeons from India and abroad.
Other good endoscopic spine training programs are by Prof. Gore, Prof. Deopujari,
and Dr. Rohidas. In addition to live and cadaver programs, one can also practice on
indigenous hands-on models.[49]
Conclusion
Indian surgeons have made both technical and technological innovations in the endoscopic
spine field. The surgeries have proved to be better or a viable alternative to open
or microscopic techniques. Many different training programs provide a bright future
for the younger generation.
