Severe Neuropathic eye / Ocular Pain and the Role of the Autonomic Nervous System and Sphenopalatine Ganglion Blocks in Diagnosis and Therapeutic Treatments.
The diagnosis of neuropathic ocular pain is typically a diagnosis of exclusion. This means that there is no clear diagnostic signs and symptoms. Altered response and perception of pain to non-painful stimuli is called Allodynia and ocular neuropathy frequently falls into this category, which may or may not have definitive causes. Misdiagnosis as dry eye frequently occurs due to lack of definitive diagnostic markers.
It is extremely important to always consider this as a Trigeminal Nerve Disorder even if other diagnosis also apply. It is also crucial in treatment to consider the Autonomic Nervous System input to the Trigeminal Nervous System. Treatment with a Diagnostic Neuromuscular Orthotic can often relieve pain which may be extremely important with a diagnosis of exclusion. Autonomic Blocks, and Specifically Sphenopalatine Ganglion Blocks also have frequent excellent responses in relief of pain and can help focus the diagnosis if pain is eliminated or shows major improvement.
The diagnosis can be complicated due to the varied diagnostic names given to this disorder by different providers including: Corneal Neuropathic Pain, Cornea Allodynia, Corneal Neuralgia, Keratoneuralgia, Ocular Pain Syndrome, Cornea Neuropathic Disease.
Clinical history varies and it has been reported in association with dry eyes after Lasik Surgery. Patients presenting with blepharospasm which may be secondary to chronic corneal nociceptor hyperactivity. If there is no know causes it is often attributed to Ocular surface disease, systemic disorders such as fibromyalgia or autoimmune diseases or systemic pain syndromes. Dry eyes may or may not be a cause and effect of this problem however it may be diagnosed as a cause if there are no other objective symptoms.
Other Possible Causes include:
• Referred pain from Myofascial Trigger Points
• Sinus issues referring to eye
• Facial Pain with Ocular Component
• Ocular medication toxicity
• Trauma from foreign particles leading to abrasion, infiltrate, ulcers, or other conditions
• Trauma or other Contact Lens related issues
• Uveitis or Eye Inflammation of Uvea
• Chemical Burns
• Post-Herpetic Neuralgia
• Trigeminal Neuralgia: Especially Atypical Trigeminal Neuralgia
• Secondary to Temporomandibular Disorders
• Autonomic Dysfunction of the Trigeminal Nervous System
Due to the multiple serious organic medical issues an Opthamologist should always be involved in treatment and ongoing patient management.
It is essential in the lack of organic disease to consider noxious inputs into the Trigeminal Nervous System from oral structures including Masticatory Muscles and the TemporoMandibular Joints (TMJ). TMD or Temporal Mandibular Dysfunction is frequently associated with complaints of eye pain that are alleviated with appropriate dental treatment. Neuromuscular diagnostic orthotics can often relieve eye pain diagnosed as ocular neuropathic pain. These techniques were first described by Dr Barney Jankelson in Seattle. The concept of TMJ Disorders was first described by Costen in 1936. TMJ Disorders (TMD) have been called “The Great Imposter” because they mimic so many different disorders. https://www.tandfonline.com/doi/pdf/10.1179/crn.2013.001?needAccess=true
UNDERSTANDING SPHENOPALATINE GANGLION BLOCKS:
HISTORY & UTILIZATION
In 1908 Dr Greenfield Sluder first described Sphenopalatine Ganglion Blocks to treat Sluder’s Neuralgia. The Sphenopalatine Ganglion is the largest Parassympathetic Ganglion of the Cranium and one of four Parasympathetic Ganglia associated with the Trigeminal Nervous System. He described a procedure that used a nasal approach to block the Sphenopalatine Ganglion with anesthetic delivered to nasal mucosa that passes into the Pterygopalatine Fossa where the Ganglion is found. The Sphenopalatine Ganglion is also called the Pterygopalatine Ganglion, the Nasal Ganglion and Sluder’s Ganglion.
Dr Sluder was the Director and Chair of the Department of Otolaryngology at Washington University School of Medicine in St Louis and wrote 2 books on the the Neurology of the Sphenoplaatine Ganglion. His second book “Nasal Neurology: Headaches and Eye Disorders” was specifically named to encourage opthamologists and neurologists to consider these important structures.
The Annals of Internal Medicine (JAMA) had a 1930 article by Hiram Byrd and Wallace Byrd on 2000 patients and 10,000 blocks with almost 100% relief of symptoms and no negative side effects. Many of these patients had eye pain that might be diagnosed today as Ocular Neuropathy. The amazing success of these blocks almost became part of “Forgotten Medicine” when pharmaceutical approaches displaced proven treatment methods.
Sphenopalatine Ganglion Blocks may have been lost if not for a popular book “Mirtacles on Park Avenue” by Gerber who described the medical practice of Dr Milton Reder an Octogenerian Otholaryngologist in Manhattan whose entire practice was use of Sphenopalatine Ganglion Blocks to treat untreatable conditions. Dr Reder had used these techniques for many decades.
Learn more about the Sphenopalatine Ganglion Block:
SPG Blocks and Eye Pain
Why Sphenopalatine Ganglion Blocks are effective for eye pain.
An excellent resource in Cranio discussing Neuromuscular Dentistry and Sphenopalatine Ganglion Blocks.
Neuromuscular dentistry and the role of the autonomic nervous system: Sphenopalatine ganglion blocks and neuromodulation. An International College of Cranio Mandibular Orthopedics (ICCMO) position paper
Ira L Shapira 1
• DOI: 10.1080/08869634.2019.1592807
The Sphenopalatine Ganglion (SPG) is known to play an integral role in the pathophysiology of a wide variety of orofacial pains involving the jaws, sinuses, eyes and the trigeminal autonomic cephalalgias. It supplies direct parasympathetic innervation to the trigeminal and facial nerves. Sympathetic innervation from the superior sympathetic chain passes thru the SPG to the trigeminal and facial nerves.This paper reviews relevant and significant literature on SPG Blocks and Neuromodulation published in peer reviewed medical and dental journals. Neuromuscular Dentistry employs ULF-TENS to relax musculature and simultaneously provide neuromodulation to the ganglion.Conclusion: The effects of ULF-TENS on the autonomic nervous system acts on the Limbic System and Hypothalamus (H-P-A) to address Axis II issues during neuromuscular dental procedures. It also directly affects the autonomic component of the trigeminal nerve involved in almost all headaches and migraines as well as the Myofascial and Joint disorders of TMD.
Keywords: Neuromuscular Dentistry; Sphenopalatine Ganglion (SPG) Block; Sphenopalatine Ganglion (SPG) Neuromodulation; Trigeminal Autonomic Nervous system; ULF-TENS.
Another excellent text on this subject can be found following this article: “Understanding Neuropathic Corneal Pain-Gaps and Current Therapeutic Approaches” by Sunali GoyalMD and Pedram Hamrah MD