Dr. Martinelli's Vision & Neurology Casebook: Real World Insights for Primary Eye Care & Family Medicine

By John R Martinelli

Learn to master high-yield clinical concepts bridging gaps between primary eye care, general medicine, and neurology, with a treasure trove of real-world cases presented to enhance your critical thinking and patient management.

What You'll Find Inside:

• Language: English
• Publisher: Ophthalmic Physician Publishing
• Release date: Jun 21, 2024
• ISBN: 9798330246083

John R Martinelli

With 27 years as an Optometric Physician on the front lines prior to earning his MD, Dr. Martinelli now brings more than 35 years of private practice experience, combined with medicine, providing rare insight and guidance with respect to patient care philosophy. Dr. Martinelli is a graduate of St. George's University School of Medicine, Pennsylvania College of Optometry, as well as Washington & Jefferson College. He is a physician member of the American Medical Association (AMA), Fellow of the American Academy of Optometry (FAAO), and the American Optometric Association (AOA). His clinical articles have been featured over the years in various publications, and he also very much enjoys teaching, with more than a decade mentoring countless students as a private practice preceptor in ocular disease for the Pennsylvania College of Optometry. Dr. Martinelli has spoken for Alcon and Allergan, as well as nationally and internationally with topics involving medical eye care, glaucoma, and refractive surgery such as LASIK.

Book preview

Section 1

Muscle

Neuromuscular diseases reveal the incredible intricacy and resilience of the human body, pushing us to find new ways to support and heal.

– Dr. Stanley Appel

Eye Won’t Wake Up

History of Present Illness (HPI)

A 78-year-old lady is in your chair. For the last several months, she has had trouble opening her left eye when she wakes up in the morning. However, when she rubs it, after a couple of minutes it becomes easier to open and goes back to normal.

Review of Systems (ROS)

She has had no recent change in vision, loss of vision, diplopia, or pain. She sometimes notices her lid also droops during the day. No symptoms of dry eye or discharge. No recent weight loss, fever, or night sweats. Occasionally, she experiences mild neck discomfort.

Past Medical History (PMH)

Hypothyroidism and iron deficiency anemia. Anxiety and depression over many years. A lipoma in her neck was discovered during her last physical exam.

Family History (FH)

Her parents both had a history of cardiovascular disease, hypertension, and diabetes.

Medications and Allergies

She takes Levothyroxine 75 mcg, sertraline 50 mg daily, and iron supplements. She has no known allergies to medications, foods, or environmental factors.

Ophthalmic Examination

Best Corrected Visual Acuity (BCVA): 20/25 OD, 20/30 OS.

Pupils: Pupils equal, round, reactive to light and accommodation, no afferent pupillary defect. PERRLA (-)APD

Extraocular Muscles (EOMs): Full, without diplopia.

Visual Field (VF): Full OU.

Intraocular Pressure (IOP): 19 OD, 20 OS.

Anterior Segment: Clear cornea, quiet and deep anterior chamber, pseudophakic with nicely placed posterior chamber IOL’s OU.

Posterior Segment: Optic disc, macula, vessels, vitreous, retina unremarkable OU. Trace macular drusen and pigment mottling OU.

Eyelids: Dermatochalasis OU, with ptosis OS.

Optical Coherence Tomography (OCT): Normal optic nerve and retinal nerve fiber layer (rNFL) OU, macula with early drusen and RPE changes OU. No evidence of disc edema OU.

Think Deeper!

Discussion and Management

Her difficulty opening her left eye in the mornings, as well as transient ptosis during the day, brings to your mind multiple possible sources and scenarios.

You consider Myasthenia Gravis, particularly ocular myasthenia, which can manifest as progressive muscle weakness worsening with fatigue or toward the end of the day. In her case, early morning fatigue with ptosis noticed during the day may be your first clue. The improvement in ptosis after rubbing her eye suggests a mechanical enhancement of neuromuscular transmission, supporting an etiology of myasthenia.

Your diagnostic investigations should involve specific labs for confirmation, and to rule-out other potential sources. Labs targeting acetylcholine receptor (AChR) antibodies is your top priority, as their presence is highly specific for myasthenia gravis. These include binding antibodies, which are the most commonly detected, blocking antibodies that interfere with acetylcholine binding, and modulating antibodies that alter the number of acetylcholine receptors and their functions on the muscle surface. When AChR antibodies are not detected, labs for muscle-specific kinase (MuSK) antibodies become key in diagnosing seronegative myasthenia gravis.

Electromyography (EMG) is also an important diagnostic tool. Repetitive nerve stimulation measures the electrical response of muscles to repeated nerve stimulation, where a decremental response indicates myasthenia gravis. Single-fiber EMG, a more sensitive test, detects abnormalities in neuromuscular transmission providing further confirmation.

The edrophonium test, also known as the Tensilon test, involves administering IV edrophonium which temporarily improves muscle function in individuals with myasthenia by inhibiting acetylcholinesterase. This increases the availability of acetylcholine leading to improved neuromuscular response. This improvement following administration also supports the diagnosis. The tensilon test is not utilized as it once was due to high false positives, and the development of serologic antibody testing.

Another simple but effective test is the ice pack test. With ptosis, applying an ice pack to the eyelid for a few minutes can temporarily yield improvement, suggesting myasthenia. This is because the transmission of acetylcholine is improved at cooler