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Despite the temporary nature of the vision loss, those experiencing amaurosis fugax are usually advised to consult a physician immediately as it is a symptom that may herald serious vascular events, including stroke. Restated, “because of the brief interval between the transient event and a stroke or blindness from temporal arteritis, the workup for transient monocular blindness should be undertaken without delay.” If the patient has no history of giant cell arteritis, the probability of vision preservation is high; however, the chance of a stroke reaches that for a hemispheric TIA. Therefore, investigation of cardiac disease is justified.
A diagnostic evaluation should begin with the patient's history, followed by a physical exam, with particular importance being paid to the ophthalmic examination with regards to signs of ocular ischemia. When investigating amaurosis fugax, an ophthalmologic consult is absolutely warranted if available. Several concomitant laboratory tests should also be ordered to investigate some of the more common, systemic causes listed above, including a complete blood count, erythrocyte sedimentation rate, lipid panel, and blood glucose level. If a particular cause is suspected based on the history and physical, additional relevant labs should be ordered.
If laboratory tests are abnormal, a systemic disease process is likely, and, if the ophthalmologic examination is abnormal, ocular disease is likely. However, in the event that both of these routes of investigation yield normal findings or an inadequate explanation, noninvasive duplex ultrasound studies are recommended to identify carotid artery disease. Most episodes of amaurosis fugax are the result of stenosis of the ipsilateral carotid artery. With that being the case, researchers investigated how best to evaluate these episodes of vision loss, and concluded that for patients ranging from 36–74 years old, "...carotid artery duplex scanning should be performed...as this investigation is more likely to provide useful information than an extensive cardiac screening (ECG, Holter 24-hour monitoring, and precordial echocardiography)." Additionally, concomitant head CT or MRI imaging is also recommended to investigate the presence of a “clinically silent cerebral embolism.”
If the results of the ultrasound and intracranial imaging are normal, “renewed diagnostic efforts may be made,” during which fluorescein angiography is an appropriate consideration. However, carotid angiography is not advisable in the presence of a normal ultrasound and CT.
If the diagnostic workup reveals a systemic disease process, directed therapies to treat that underlying cause should be initiated. If the amaurosis fugax is caused by an atherosclerotic lesion, aspirin is indicated, and a carotid endarterectomy considered based on the location and grade of the stenosis. Generally, if the carotid artery is still patent, the greater the stenosis, the greater the indication for endarterectomy. "Amaurosis fugax appears to be a particularly favorable indication for carotid endarterectomy. Left untreated, this event carries a high risk of stroke; after carotid endarterectomy, which has a low operative risk, there is a very low postoperative stroke rate." However, the rate of subsequent stroke after amaurosis is significantly less than after a hemispheric TIA, therefore there remains debate as to the precise indications for which a carotid endarterectomy should be performed. If the full diagnostic workup is completely normal, patient observation is recommended.
Optic papillitis is a specific type of optic neuritis. Inflammation of the optic nerve head is called "papillitis" or "intraocular optic neuritis"; inflammation of the orbital portion of the nerve is called "retrobulbar optic neuritis" or "orbital optic neuritis". It is often associated with substantial losses in visual fields, pain on moving the globe, and sensitivity to light pressure on the globe. It is often an early sign of multiple sclerosis.
Papillitis may have the same appearance as papilledema. However, papillitis may be unilateral, whereas papilledema is almost always bilateral. Papillitis can be differentiated from papilledema by an afferent pupillary defect (Marcus Gunn pupil), by its greater effect in decreasing visual acuity and color vision, and by the presence of a central scotoma. Papilledema that is not yet chronic will not have as dramatic an effect on vision. Because increased intracranial pressure can cause both papilledema and a sixth (abducens) nerve palsy, papilledema can be differentiated from papillitis if esotropia and loss of abduction are also present. However, esotropia may also develop secondarily in an eye that has lost vision from papillitis. Retrobulbar neuritis, an inflamed optic nerve, but with a normal-appearing nerve head, is associated with pain and the other findings of papillitis. Pseudopapilledema is a normal variant of the optic disk, in which the disk appears elevated, with indistinct margins and a normal vascular pattern. Pseudopapilledema sometimes occurs in hyperopic individuals.
Workup of the patient with papillitis includes lumbar puncture and cerebrospinal fluid analysis. B henselae infection can be detected by serology. MRI is the preferred imaging study. An abnormal MRI is associated with a worse visual outcome.
ONH is diagnosed by ophthalmoscopic examination. Patients with ONH exhibit an optic nerve that appears smaller than normal and different in appearance from small optic nerves caused by other eye conditions such as optic (nerve) atrophy.
DM:DD ratio has proven to be a clinically useful measurement to help diagnose optic nerve hypoplasia. Where "DM" represents the distance from Disk to Macula, and "DD" represents Disc Diameter.
The mean disc diameter (DD) is (Vertical diameter of Disc+Horizontal diameter of Disc)divided by 2. The distance between the center of the disc and the macula is DM.
"Interpretation:" When the ratio of DM to DD is greater than 3, ONH is suspected, and when it is greater than 4, Optic Nerve Hypoplasia is definite.
Prior to any physical examination, the diagnosis of keratoconus frequently begins with an ophthalmologist's or optometrist's assessment of the person's medical history, particularly the chief complaint and other visual symptoms, the presence of any history of ocular disease or injury which might affect vision, and the presence of any family history of ocular disease. An eye chart, such as a standard Snellen chart of progressively smaller letters, is then used to determine the person's visual acuity. The eye examination may proceed to measurement of the localized curvature of the cornea with a manual keratometer, with detection of irregular astigmatism suggesting a possibility of keratoconus. Severe cases can exceed the instrument's measuring ability. A further indication can be provided by retinoscopy, in which a light beam is focused on the person's retina and the reflection, or reflex, observed as the examiner tilts the light source back and forth. Keratoconus is amongst the ophthalmic conditions that exhibit a scissor reflex action of two bands moving toward and away from each other like the blades of a pair of scissors.
If keratoconus is suspected, the ophthalmologist or optometrist will search for other characteristic findings of the disease by means of slit lamp examination of the cornea. An advanced case is usually readily apparent to the examiner, and can provide for an unambiguous diagnosis prior to more specialized testing. Under close examination, a ring of yellow-brown to olive-green pigmentation known as a Fleischer ring can be observed in around half of keratoconic eyes. The Fleischer ring, caused by deposition of the iron oxide hemosiderin within the corneal epithelium, is subtle and may not be readily detectable in all cases, but becomes more evident when viewed under a cobalt blue filter. Similarly, around 50% of subjects exhibit Vogt's striae, fine stress lines within the cornea caused by stretching and thinning. The striae temporarily disappear while slight pressure is applied to the eyeball. A highly pronounced cone can create a V-shaped indentation in the lower eyelid when the person's gaze is directed downwards, known as Munson's sign. Other clinical signs of keratoconus will normally have presented themselves long before Munson's sign becomes apparent, and so this finding, though a classic sign of the disease, tends not to be of primary diagnostic importance.
A handheld keratoscope, sometimes known as "Placido's disk", can provide a simple noninvasive visualization of the surface of the cornea by projecting a series of concentric rings of light onto the cornea. A more definitive diagnosis can be obtained using corneal topography, in which an automated instrument projects the illuminated pattern onto the cornea and determines its topography from analysis of the digital image. The topographical map indicates any distortions or scarring in the cornea, with keratoconus revealed by a characteristic steepening of curvature which is usually below the centreline of the eye. The technique can record a snapshot of the degree and extent of the deformation as a benchmark for assessing its rate of progression. It is of particular value in detecting the disorder in its early stages when other signs have not yet presented.
Once keratoconus has been diagnosed, its degree may be classified by several metrics:
- The steepness of greatest curvature from 'mild' ( 52 D);
- The morphology of the cone: 'nipple' (small: 5 mm and near-central), 'oval' (larger, below-center and often sagging), or 'globus' (more than 75% of cornea affected);
- The corneal thickness from mild (> 506 μm) to advanced (< 446 μm).
Increasing use of corneal topography has led to a decline in use of these terms.
The visual prognosis in optic nerve hypoplasia is quite variable. Occasionally, optic nerve hypoplasia may be compatible with near-normal vision; in other cases, one or both eyes may be functionally, or legally blind. Although most patients with only optic nerve involvement lead normally productive lives, those with accompanying endocrine dysfunction or other midline cerebral abnormalities are more at risk for on-going intellectual and other disabilities.
A radiographic evaluation using an X-ray, CT scan, or MRI can determine if there is damage to the spinal column and where it is located. X-rays are commonly available and can detect instability or misalignment of the spinal column, but do not give very detailed images and can miss injuries to the spinal cord or displacement of ligaments or disks that do not have accompanying spinal column damage. Thus when X-ray findings are normal but SCI is still suspected due to pain or SCI symptoms, CT or MRI scans are used. CT gives greater detail than X-rays, but exposes the patient to more radiation, and it still does not give images of the spinal cord or ligaments; MRI shows body structures in the greatest detail. Thus it is the standard for anyone who has neurological deficits found in SCI or is thought to have an unstable spinal column injury.
Neurological evaluations to help determine the degree of impairment are performed initially and repeatedly in the early stages of treatment; this determines the rate of improvement or deterioration and informs treatment and prognosis. The ASIA Impairment Scale outlined above is used to determine the level and severity of injury.
Whole spine MR imaging may be used to evaluate the extent of syrinx formation (fluid filled cavity within the spinal cord) in CM dogs, developing a thermal camera-based screening test for the disorder and a method of measuring the actual syrinx volume from MR images.
Before the introduction of MRI, the diagnosis of CM and SM were commonly confused with that of allergic skin disorders, disk disease, ear infections and epilepsy. After CM was reported in human patients, the initial research was provided for the diagnosis of animals. MRI in animals is safe, however, to ensure that the patient remains motionless, light general anesthesia is required.
According to recent studies, thermography may be a useful tool in the diagnosis of CM and SM. Thermography requires no sedation or clipping of hair for a dog to be imaged by the infrared camera. After the image is captured, computer software is used to assess changes in the temperature and color pattern to detect abnormality.
Entoptic phenomena (from Greek ἐντός "within" and ὀπτικός "visual") are visual effects whose source is within the eye itself. (Occasionally, these are called entopic phenomena, which is probably a typographical mistake.)
In Helmholtz's words; "Under suitable conditions light falling on the eye may render visible certain objects within the eye itself. These perceptions are called "entoptical"."
The first stage in the management of a suspected spinal cord injury is geared toward basic life support and preventing further injury: maintaining airway, breathing, and circulation and immobilizing the spine.
In the emergency setting, anyone who has been subjected to forces strong enough to cause SCI is treated as though they have instability in the spinal column and is immobilized to prevent damage to the spinal cord. Injuries or fractures in the head, neck, or pelvis as well as penetrating trauma near the spine and falls from heights are assumed to be associated with an unstable spinal column until it is ruled out in the hospital. High-speed vehicle crashes, sports injuries involving the head or neck, and diving injuries are other mechanisms that indicate a high SCI risk. Since head and spinal trauma frequently coexist, anyone who is unconscious or has a lowered level of consciousness as a result of a head injury is immobilized.
A rigid cervical collar is applied to the neck, and the head is held immobile with blocks on either side and the person is strapped to a backboard. Extrication devices are used to move people without moving the spine if they are still inside a vehicle or other confined space.
Modern trauma care includes a step called clearing the cervical spine, ruling out spinal cord injury if the patient is fully conscious and not under the influence of drugs or alcohol, displays no neurological deficits, has no pain in the middle of the neck and no other painful injuries that could distract from neck pain. If these are all absent, no immobilization is necessary.
If an unstable spinal column injury is moved, damage may occur to the spinal cord. Between 3 and 25% of SCIs occur not at the time of the initial trauma but later during treatment or transport. While some of this is due to the nature of the injury itself, particularly in the case of multiple or massive trauma, some of it reflects the failure to immobilize the spine adequately.
SCI can impair the body's ability to keep warm, so warming blankets may be needed.
Entoptic images have a physical basis in the image cast upon the retina. Hence, they are different from optical illusions, which are perceptual effects that arise from interpretations of the image by the brain. Because entoptic images are caused by phenomena within the observer's own eye, they share one feature with optical illusions and hallucinations: the observer cannot share a direct and specific view of the phenomenon with others.
Helmholtz comments on phenomena which could be seen easily by some observers, but could not be seen at all by others. This variance is not surprising because the specific aspects of the eye that produce these images are unique to each individual. Because of the variation between individuals, and the inability for two observers to share a nearly identical stimulus, these phenomena are unlike most visual sensations. They are also unlike most optical illusions which are produced by viewing a common stimulus. Yet, there is enough commonality between the main entoptic phenomena that their physical origin is now well understood.
The type of treatment needed for dogs diagnosed with CM/SM depends on the severity of the condition and the age of the dog. Young dogs with clinical signs should be considered for surgical removal to minimize the progression of the disease as the dog ages. Older dogs with little or no clinical signs may be treated medically, rather than surgically. However, severe cases of CM/SM may require surgery regardless of age. The goal of surgery is syrynx decompression through restoration of normal cerebrospinal fluid circulation.
The surgical treatment of CM in dogs is described as "foramen magnum decompression FMD". Despite an approximately 80% success rate with this surgical technique, there is a 25% to 50% relapse, primarily due to excessive scar tissue formation at the decompression site. A cranioplasty may be performed instead, in which a plate, constructed using titanium mesh and bone cement, is fixed to the back of the skull following a standard FMD procedure. The procedure had been effective in humans. The postoperative relapse rate associated with the titanium cranioplasty procedure is less than 7%.
Imaging is not typically needed in the initial diagnosis or treatment of back pain. However, if there are certain "red flag" symptoms present plain radiographs (x-ray), CT scan, or magnetic resonance imaging (MRI) may be recommended. These red flags include:
- History of cancer
- Unexplained weight loss
- Immunosuppression
- Urinary infection
- Intravenous drug use
- Prolonged use of corticosteroids
- Back pain not improved with conservative management
- History of significant trauma
- Minor fall or heavy lift in a potentially osteoporotic or elderly individual
- Acute onset of urinary retention, overflow incontinence, loss of anal sphincter tone, or fecal incontinence
- Saddle anesthesia
- Global or progressive motor weakness in the lower limbs
Because there are various causes for back injuries, prevention must be comprehensive. Back injuries are predominant in manual labor so the majority low back pain prevention methods have been applied primarily toward biomechanics Prevention must come from multiple sources such as education, proper body mechanics, and physical fitness.
Imaging is indicated when there are red flags, ongoing neurological symptoms that do not resolve, or ongoing or worsening pain. In particular, early use of imaging (either MRI or CT) is recommended for suspected cancer, infection, or cauda equina syndrome. MRI is slightly better than CT for identifying disc disease; the two technologies are equally useful for diagnosing spinal stenosis. Only a few physical diagnostic tests are helpful. The straight leg raise test is almost always positive in those with disc herniation. Lumbar provocative discography may be useful to identify a specific disc causing pain in those with chronic high levels of low back pain. Similarly, therapeutic procedures such as nerve blocks can be used to determine a specific source of pain. Some evidence supports the use of facet joint injections, transforminal epidural injections and sacroilliac injections as diagnostic tests. Most other physical tests, such as evaluating for scoliosis, muscle weakness or wasting, and impaired reflexes, are of little use.
Complaints of low back pain are one of the most common reasons people visit doctors. For pain that has lasted only a few weeks, the pain is likely to subside on its own. Thus, if a person's medical history and physical examination do not suggest a specific disease as the cause, medical societies advise against imaging tests such as X-rays, CT scans, and MRIs. Individuals may want such tests but, unless red flags are present, they are unnecessary health care. Routine imaging increases costs, is associated with higher rates of surgery with no overall benefit, and the radiation used may be harmful to one's health. Fewer than 1% of imaging tests identify the cause of the problem. Imaging may also detect harmless abnormalities, encouraging people to request further unnecessary testing or to worry. Even so, MRI scans of the lumbar region increased by more than 300% among United States Medicare beneficiaries from 1994 to 2006.
The application of MRI plays a significant role in the early diagnosis and treatment of SCIWORA in children and adults. Recently, systematic reviews on SCIWORA described the clinical and radiological patterns and correlations with neurological outcome.C.K. Boese und P. Lechler: "Spinal cord injury without radiologic abnormalities in adults: a systematic review." In: "Journal of Trauma and Acute Care Surgery." 78, 2015, S. 320-330 .Boese CK, Oppermann J, Siewe J, Eysel P, Scheyerer MJ, Lechler P.: "Spinal cord injury without radiologic abnormality in children: a systematic review and meta-analysis." In: "Journal of Trauma and Acute Care Surgery." 75, 2013. Boese and Lechler proposed a MRI-based classification for SCIWORA which correlated with the neurological outcome:
In most cases of low back pain, medical consensus advises not seeking an exact diagnosis but instead beginning to treat the pain. This assumes that there is no reason to expect that the person has an underlying problem. In most cases, the pain goes away naturally after a few weeks. Typically, people who do seek diagnosis through imaging are not likely to have a better outcome than those who wait for the condition to resolve.
Laboratory testing may include white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP).
- Elevated ESR could indicate infection, malignancy, chronic disease, inflammation, trauma, or tissue ischemia.
- Elevated CRP levels are associated with infection.
Surgery may be useful in those with a herniated disc that is causing significant pain radiating into the leg, significant leg weakness, bladder problems, or loss of bowel control. Discectomy (the partial removal of a disc that is causing leg pain) can provide pain relief sooner than nonsurgical treatments. Discectomy has better outcomes at one year but not at four to ten years. The less invasive microdiscectomy has not been shown to result in a significantly different outcome than regular discectomy with respect to pain. It might however have less risk of infection.
The presence of cauda equina syndrome (in which there is incontinence, weakness and genital numbness) is considered a medical emergency requiring immediate attention and possibly surgical decompression. Regarding the role of surgery for failed medical therapy in people without a significant neurological deficit, a Cochrane review concluded that "limited evidence is now available to support some aspects of surgical practice".
A 69-year-old male with tethered cord that was low lying and associated with Spina Bifida in the form of meningocele that was operated on as an infant, was studied in this research. He presented with worsened neurological deficits due to progressive lumbar stenosis at the L3-L4 level which was associated with the spinal discs degenerating. Extreme lateral inter body fusion (XLIF) was performed to allow for indirect spinal cord decompression and stability which allowed for neurological improvement. The role of the XLIF approach to this treatment was emphasized and compared to other surgical approaches. It was concluded that surgical decompression should be performed as soon as possible to prevent any further neurological damage. Also concluded was that the XLIF approach is safe and fast and is indicative of a good surgical option to obtain spinal cord indirect decompression and lumbar inter body fusion.
Radiculopathy is a diagnosis commonly made by physicians in primary care specialities, chiropractic, orthopedics, physiatry, and neurology. The diagnosis may be suggested by symptoms of pain, numbness, and weakness in a pattern consistent with the distribution of a particular nerve root. Neck pain or back pain may also be present. Physical examination may reveal motor and sensory deficits in the distribution of a nerve root. In the case of cervical radiculopathy, Spurling's test may elicit or reproduce symptoms radiating down the arm. In the case of lumbosacral radiculopathy, a Straight leg raise maneuver may exacerbate radiculopathic symptoms. Deep tendon reflexes (also known as a Stretch reflex) may be diminished or absent in areas innervated by a particular nerve root.
For further workup, the American College of Radiology recommends that projectional radiography is the most appropriate initial study in all patients with chronic neck pain. Two additional diagnostic tests that may be of use are magnetic resonance imaging and electrodiagnostic testing. Magnetic resonance imaging (MRI) of the portion of the spine where radiculopathy is suspected may reveal evidence of degenerative change, arthritic disease, or another explanatory lesion responsible for the patient's symptoms. Electrodiagnostic testing, consisting of NCS (Nerve conduction study) and EMG (Electromyography), is also a powerful diagnostic tool that may show nerve root injury in suspected areas. On nerve conduction studies, the pattern of diminished Compound muscle action potential and normal sensory nerve action potential may be seen given that the lesion is proximal to the Posterior root ganglion. Needle EMG is the more sensitive portion of the test, and may reveal active denervation in the distribution of the involved nerve root, and neurogenic-appearing voluntary motor units in more chronic radiculopathies. Given the key role of electrodiagnostic testing in the diagnosis of acute and chronic radiculopathies, the American Association of Neuromuscular & Electrodiagnostic Medicine has issued evidence-based practice guidelines, for the diagnosis of both cervical and lumbosacral radiculopathies. The American Association of Neuromuscular & Electrodiagnostic Medicine has also participated in the Choosing Wisely Campaign and several of their recommendations relate to what tests are unnecessary for neck and back pain.
The presence of certain signs, termed "red flags", indicate the need for further testing to look for more serious underlying problems, which may require immediate or specific treatment. The presence of a red flag does not mean that there is a significant problem. It is only suggestive, and most people with red flags have no serious underlying problem. If no red flags are present, performing diagnostic imaging or laboratory testing in the first four weeks after the start of the symptoms has not been shown to be useful.
The usefulness of many red flags are poorly supported by evidence. The most useful for detecting a fracture are: older age, corticosteroid use, and significant trauma especially if it results in skin markings. The best determinant of the presence of cancer is a history of the same.
With other causes ruled out, people with non-specific low back pain are typically treated symptomatically, without exact determination of the cause. Efforts to uncover factors that might complicate the diagnosis, such as depression, substance abuse, or an agenda concerning insurance payments may be helpful.
Examination for pain sensation, by pinprick, shows leg (lumbar nerves) analgesia with perineal (sacral nerves) escape. The maintenance of perineal sensation with absence of pain sensation over the lumbar nerve roots is typical for an extra-medullary and intra-thecal (outside the cord and within the dural sheath) process. Inability to walk, with this unusual sensory examination completes a triad of signs and usually represents spinal tuberculosis. The triad is paraplegia with lumbar loss of pain sensation and presence of perineal altered sensation.
Diagnosis is usually confirmed by an MRI scan or CT scan, depending on availability. Early surgery in acute onset of severe cases has been reported to be important.
The intradural anatomic features of the filum terminale in fresh human cadavers was evaluated, which helped to analyze the morphological parameters relevant for diagnosing tethered spinal cord syndrome. The research was conducted by the scientists by dissecting 41 cadavers and then evaluated the height, weight, age, FT length, FT diameter at midpoint and initial point, and the topographic relationships of the initial fusion points adjacent to the vertebrae. This anatomic study concluded that there was a large variation in the parameters of the filum terminale and that 6 out of the 41 cadavers met the criteria for tethered spinal cord syndrome.
The prognosis for complete recovery is dependent upon many factors. The most important of these is the severity and duration of compression upon the damaged nerve(s). Generally, the longer the time before intervention to remove the compression causing nerve damage, the greater the damage caused to the nerve(s).
Damage can be so severe that nerve regrowth is impossible, and the nerve damage will be permanent. In cases where the nerve has been damaged but is still capable of regrowth, recovery time is widely variable. Surgical intervention with decompression of the cauda equina can assist recovery. Delayed or severe nerve damage can mean up to several years' recovery time because nerve growth is exceptionally slow.
Review of the literature indicates that around 50-70% of patients have urinary retention (CES-R) on presentation with 30-50% having an incomplete syndrome (CES-I). The latter group, especially if the history is less than a few days, usually requires emergency MRI to confirm the diagnosis followed by prompt decompression. CES-I with its more favourable prognosis may become CES-R at a later stage.