Patent Publication Number: US-2002011250-A1

Title: Procedure for evaluating vestibular dysfunction

Description:
[0001] This application is based upon and claims priority of U.S. Provisional Patent Application Serial No. 60/219,788 filed Jul. 19, 2000, entitled “Procedure for Evaluating Vestibular Dysfunction.” 
    
    
     
       BACKGROUND  
       FIELD OF THE INVENTION  
       [0002] The invention relates to the diagnosis of balance disorders, and particularly to a network-based system for remotely evaluating balance-related diagnostic test data.  
       [0003] The brain maintains a sense of spatial orientation and equilibrium by integrating and interpreting a variety of different sensory inputs from the eyes, the inner ear, and the body&#39;s somasensory system. The most complex source of spatial cues is the vestibular system of the inner ear. Indeed, studies have shown that the vast majority of athletes complaining of dizziness have a vestibular abnormality.  
       [0004] The inner ear has two types of spatial orientation sensors. Three endolymphatic-fluid-filled semi-circular canals provide sensory information about velocity, rotation, and angular motion. Two otoliths in each inner ear, the utricle and the saccule, sense horizontal and vertical acceleration, respectively. Specialized hair cells in the otoliths and the ampullae (the dilated portions of the semi-circular canals) are displaced by movement in one direction or the other. These displacements are converted to neural signals, which are transmitted by the vestibular nerve to the reticular activating system and lymbic system of the brain. When the head is in a normal upright position, the hair cells in each ear fire equally at a static rate. When the head tilts to the right or to the left, the hair cells in each ear fire at different rates. The central nervous system interprets the inter-aural differences in the firing rate to determine the head&#39;s spatial orientation.  
       [0005] The sensory data from the inner ear is complemented by visual cues from the eyes and somatosensory spatial cues from the muscles and skin, which sense pressure and muscle tensioning caused by standing, sitting, or lying down.  
       [0006] Sensory mismatch occurs when the various sensory inputs of the body do not agree with one another. For example, a room on a ship in a stormy sea may look upright at the same time the gravity sensors in the inner ear and pressure sensors in the feet indicate that the room is tilted at an angle. Sensory mismatch can result in nausea, queaziness, and disorientation.  
       [0007] Several different conditions can cause the balance system to malfunction. Labyrinthitis and Vestibular Neuronitis are conditions that describe the inflammation of the inner ear or the vestibular nerve, typically caused by a viral infection. These conditions are characterized by a sudden onset of vertigo which is “spinning” in nature, extreme nausea, and vomiting.  
       [0008] Endolymphatic Hydrops is a condition of the inner ear related to the inability of the ear to regulate its fluid balance, resulting in an episodic buildup of pressure within the balance and hearing organs. This disorder is characterized by spontaneous episodes of vertigo lasting up to several hours, fullness of the ear, “ringing” or noise in the ear, and/or hearing loss. When all of these symptoms are present, the disorder is described as Meniere&#39;s Disease. Endolymphatic Hydrops has many causes, including Labyrinthitis, perilymphatic fistula, concussions, noise trauma, autoimmune inner ear disease, and ear surgery.  
       [0009] Benign Paroxysmal Positional Spinning (BPPV) is a condition characterized by the positional onset of vertigo. Brief episodes of vertigo may be caused by lying down, rolling over in bed, or tilting the head back to look up. Canalithiasis, a form of BPPV associated with vertigo lasting only a few seconds, is thought to be caused by misplaced calcium carbonate crystals (otoconia) that have been dislodged from the inner ear and which float freely within the semi-circular canals in response to gravity. Cupulolithiasis, a form of BPPV associated with vertigo lasting several minutes, is caused by misplaced otoconia stuck to the cupula that constantly stimulate the balance sensor.  
       [0010] Perilymphatic fistula is caused by a hole in the inner ear that leaks endolymphatic fluid into the middle ear. Leakage results in brief episodes of vertigo triggered by rapid changes in middle ear pressure, such as that caused by coughing, sneezing, lifting, scuba diving, head trauma, or rapid changes in altitude.  
       [0011] Vestibular migraines are short spells of vertigo, lasting several minutes in duration, accompanied by headaches. This condition is distinguished by the absence of tinnitus or hearing loss.  
       [0012] Vertebribasular Insufficiency (VBI) is a common vascular disorder characterized by decreased blood flow through the vertebrobasilar artery system, which can result in an abrupt onset of vertigo that resolves after several minutes of lying down. Such episodes are accompanied by other VBI symptoms, including visual hallucinations, drop attacks, visual field deficits, diplopia, and headache.  
       [0013] Otoxicity is a condition characterized by damage done to the hearing and balance systems by drugs. Common medications that can permanently damage the inner ear system include Aminoglycoside antibiotics and Cisplatin. Symptoms may include gait unsteadiness, imbalance, and oscillopsia (a bouncing sensation of the horizon).  
       [0014] Other disorders are characterized by gravity sensors in the otolith organs being excessively responsive to internal pressure changes such as that caused by physical activity and to sound. Damage can also be caused by tumors and viral infections that affect the vestibular nerve.  
       [0015] Vestibular abnormalities cause not only the common symptoms of dizziness, spinning, unsteadiness, and nausea, but also cognitive dysfunction, including short-term memory deficits, inability to concentrate or focus on a task, panic attacks, and depression. These cognitive symptoms are caused by the brain&#39;s natural compensation mechanisms. To suppress the sensory input from the malfunctioning ear, the brain decreases the relative function of the brain&#39;s reticular activating system (RAS) (the portion of the brain responsible for “awareness” or the feeling of being “awake” or “clear”) and limbic system (the portion of the brain responsible for moods and emotions). This adaptive response results in a lowered level of consciousness, manifesting itself in difficulties with cognitive tasks, physical coordination, and short-term memory.  
       [0016] Approximately 11.3 million physician&#39;s office visits per year, or five to ten percent of all office visits, are for the complaint of dizziness. A National Institutes of Health study estimates that forty percent of the population over the age of forty have experienced or will experience a “dizziness” disorder during their lifetime. But dizziness affects the young as well. Each year over 450,000 people, mostly young adults, suffer concussions or mild head injuries. Of those requiring short-term hospitalization, a large majority complain of persistent symptoms of dizziness or memory loss though they have been released as “completely normal.” 
       [0017] Unfortunately, many sufferers of dizziness or vertigo disorders do not receive proper diagnosis or therapy. Because the symptoms are vague, and the possible causes many, sufferers are often improperly diagnosed. Worse, sufferers are often treated as “problem patients” or inappropriately referred to psychiatrists and neurologists.  
       [0018] Athletes in contact and high-impact sports experience a high incidence of vestibular abnormalities caused by mild to severe head injuries. Unfortunately, athletes in professional and even college sports are seldom adequately diagnosed for vestibular abnormalities following a jarring collision, blow to the head, or other minor injury before being sent back onto the playing field.  
       [0019] There are a variety of tests for diagnosing balance disorders of the vestibular system. One test is a hearing test. Balance disorders are often accompanied by problems with hearing especially hearing of low frequencies. Another test is a posturography test, in which a person stands on a moving platform and the movement of the ankles and hips are measured. Posturography tests detect the vestibular-spinal reflex, which are manifested in the movements various body muscles make to maintain postural balance and coordination. Posturography tests are useful for analyzing sensory input, thus can isolate the vestibular system to detect pathology.  
       [0020] Another test is an ocular reflex test for testing how quickly and accurately the eyes move to compensate for the movement of the head. When a person without a balance disorder turns his head 30 degrees to the right, the eyes should simultaneously turn 30 degrees to the left. If the eyes turn too little or turn too much, it suggests that the vestibular system may be damaged. The vestibular ocular reflex test is useful in detecting disorders originating in, or affecting, the semi-circular canals of the ear. This is because the brain uses sensory input from the semi-circular canals to generate eye movements that match the velocity of the head movement.  
       [0021] Despite the existence of various balance dysfunction tests, and several treatment centers around the nation, balance disorder treatment is underutilized by the public at large, and athletes in particular.  
       SUMMARY OF THE INVENTION  
       [0022] The applicants&#39; research has shown that vestibular abnormalities can be treated with aggressive vestibular therapy, which modifies the central nervous system&#39;s interpretation of vestibular input. Such treatment can resolve the secondary effects of RAS inhibition and allow for return to normal performance. Early detection of vestibular abnormalities, followed by early medical intervention, may protect the vestibular apparatus following a mild head injury. Moreover, routine intervention with customized vestibular therapy can help speed return to play.  
       [0023] Accordingly, one aspect of the present invention provides standardized guidelines for diagnosis and treatment of central nervous system abnormalities such as concussions, head trauma, memory loss, confusion, or other cognitive dysfunction. A method is provided for evaluating a person suffering from a central nervous system abnormality. An initial assessment is made of the person for loss of consciousness, spinal cord injury, or a secondary injury. Then the person is asked to perform a plurality of mental exercises, such as describing the time and place, naming the teams in an athletic contest, counting digits backwards, and recalling three words or places. Next, the person is observed while performing a series of physical tests, such as standing straight with the feet together and with the eyes closed, standing straight with the heel of one foot in front of the toes of another and with the eyes closed, running twenty-yards along a straight line with the eyes open, then turning around, making a few steps, and closing the eyes. A dynamic visual acuity test is also taken. Next, machine-based hearing, dynamic-vision, and balance tests are administered to the patient, and these results are evaluated by a physician.  
       [0024] In another aspect of the invention, a method is also provided of administering a program to detect and treat a central nervous system abnormality. A patient completes an on-line consent form and questionnaire, and the results are stored in an on-line database. Later, the patient&#39;s vestibular ocular reflex and vestibular spinal reflex are tested with machine-based equipment. The results of these tests are transmitting to the on-line database. An off-site physician retrieves the test results from the on-line database and evaluates the test results to diagnose the abnormality. The physician&#39;s diagnosis is transmitted to a patient care specialist, who establishes a course of treatment for the patient. This aspect of the present invention provides off-site “expert” interpretation of balance dysfunction test data and expert guidance through a global network.  
       [0025] Another aspect of the present invention provides widespread access to state-of-the-art diagnostic modalities. Yet another aspect of the present invention provides a platform that integrates a plurality of diagnostic tools, transfers the associated data to a database on the global network, and provides for off-site diagnosis and customization of therapy. Further aspects of the present invention link a regional and/or satellite balance center, the primary care physician, the patient, and a database through a global computer network. Another aspect of the present invention centrally stores clinical and diagnostic information.  
       [0026] One of the advantages of the present invention is that it gives patients, athletes, coaches, physical trainers, and others a more complete picture of how well the vestibular system is interacting with the body and brain. Another advantage is that it aids in accurate evaluation and treatment of the specific sensory abnormality by helping a doctor to distinguish between concussional-type injuries and symptoms related to viral infections, allergies, stress, and other illnesses, producing poor athletic performance. A further advantage of the present information is that it promotes a team approach to working with patients and athletes, by coordinating athletic trainers with physicians and therapists.  
       [0027] A further advantage of the system and procedure of the present invention is that it provides cost-effective screening, diagnosis, and customized therapeutics. A yet further advantage is that a person seeking treatment can apply and set up an appointment for treatment from any personal computer linked to the global network.  
       [0028] Another advantage of the system and procedure of the present invention is that it facilitates early and aggressive vestibular therapy to minimize and compensate vestibular abnormalities. Administered early after a concussion or mild head injury, aggressive vestibular therapy helps the brain to learn to compensate for vestibular abnormalities without suppressing secondary cerebral functions. Even administered long after an injury, the present invention helps restore cognitive abilities impaired by vestibular abnormalities to normal performance.  
       [0029] Another advantage of the system and procedure of the present invention is enhancement of athletic performance. Even minor, subtle vestibular abnormalities, which might be tolerable to an ordinary individual performing ordinary tasks, can impair athletic performance and physical coordination, increasing the risk of further injury. Treatments of athletes in accordance with the present invention enhances the vestibulo-ocular reflex (VOR), increasing the athlete&#39;s clarity of vision during rapid eye movement.  
       [0030] The benefits of the present invention redound not only to athletes and concussion sufferers, but also to the elderly and the public at large. Every year, one-third to one-half of the population over age 65 experiences falls, many of which lead to orthopedic injuries, including disabling hip fractures. Many of these falls are due to, or contributed by, underlying inner ear disorders. The present invention&#39;s system and procedure for routine and early detection of balance abnormalities significantly reduces the risk of falling for elderly patients.  
       [0031] Moreover, recent clinical experience suggests that some common processing disorders, such as attention deficit disorder, learning disorder, central auditory processing disorder, and visual processing disorder, may merely be symptoms of an underlying inner ear abnormality. Therapeutic regimens administered in accordance with the present invention will improve, if not completely reverse, such central processing disorders.  
       [0032] Other aspects and advantages of the present invention will be more clearly understood after reference to the following detailed description read in conjunction with the drawings. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0033]FIG. 1 is a block diagram of one embodiment of a procedure for assessing vestibular dysfunction.  
     [0034]FIG. 2 is a functional flow diagram of one embodiment of a procedure for an in-depth assessment and treatment of the human balance system.  
     [0035]FIG. 3 is a functional flow diagram of one embodiment of an administrative procedure for evaluating an athlete&#39;s vestibular functioning and for providing a treatment program.  
     [0036]FIG. 4 is a functional flow diagram of one embodiment of a procedure for sideline evaluation of an athlete who has just suffered a head injury. 
    
    
     DETAILED DESCRIPTION  
     [0037]FIG. 1 is a block diagram of one embodiment of a procedure for assessing a central nervous system abnormality (such as a vestibular dysfunction caused by head trauma) carried out in accordance with the present invention. In this exemplary embodiment, an athlete is subjected to three or four batteries of tests. Block  120  represents an initial assessment that is made of the athlete&#39;s condition. The initial assessment comprises a plurality of preliminary evaluations denoted by blocks  122 ,  124 , and  126 . In block  122 , observation is made of, and dialogue is attempted with, the athlete in order to establish a level of consciousness. In block  124 , the athlete is examined for injury to the cervical spine. In block  126 , the athlete is examined for secondary injuries such as broken bones, sprains and pulled tendons. After this initial assessment is made, and if it is determined that the athlete is conscious and free from spinal and other secondary injuries, the athlete is subjected to another battery of tests. The battery of tests illustrated within block  130  is described as a “sideline evaluation” of the athlete. These tests are so characterized because they can be administered to an athlete on the sidelines of an athletic playing field.  
     [0038] The sideline evaluation comprises, in block  140 , a plurality of subjective (i.e., mental) tests, and in block  150 , a plurality of objective (i.e., physical) tests. The exemplary embodiment provides five subjective and five objective tests, denoted by blocks  142 - 146  and  152 - 156 , respectively.  
     [0039] In block  142 , the athlete is asked questions to determine his or her orientation to time, place, and situation. In block  143 , the athlete is asked to name the teams in the contest in which he or she was participating. In block  144 , the athlete is asked to count digits backwards as from 100 to 89. In block  145 , the athlete is given a short-term memory test challenging the athlete to recall three words or places. In block  146 , the athlete is asked very specific questions regarding the details of the contest such as the score or the quarter in which the teams are playing.  
     [0040] In block  152 , the athlete is subjected to a Romberg test, in which the standing athlete is asked to stand upright with feet together and eyes closed. The athlete&#39;s sway path and sway area are observed.  
     [0041] In block  153 , the athlete is asked to do a Tandem Romberg test for 10 seconds, which requires the athlete to stand straight with the heel of one foot placed in front of the toe of the other foot, while keeping the eyes closed. The amount which the athlete sways while in this posture is observed.  
     [0042] In block  154 , the athlete is asked to jog twenty yards in a straight line with his eyes open, then turn around, take a few steps, close the eyes and stand upright. In block  155 , the athlete is asked to do the Singleton test, which is five quick steps followed by a 180-degree turn, at which point the athlete closes the eyes, halts, and stands with feet together for 10 seconds.  
     [0043] The physical tests of blocks  152  through  155  represent tests of increasing difficulty. Of course, these tests may be replaced with other physical balance tests without departing from many of the aspects of the present invention. Other gestures the athlete may be asked to perform include standing, standing up and sitting down, reacting to a sudden pushing force in the chest, and turning 360 degrees in one place. In each case, the athlete&#39;s responses to positional stress, loss of visual input, and displacement are observed.  
     [0044] In block  156 , the athlete&#39;s dynamic visual acuity is tested by having the athlete rapidly nod his or her head from side to side and up and down in “no” and “yes” fashion, respectively, while at the same time focusing on an eye chart. The athlete&#39;s nodding should approach, but not exceed, 45 degrees from midline in each direction. The test administrator (e.g., the coach) notes the athlete&#39;s ability to properly identify alphanumeric symbols on the chart while the head is nodding.  
     [0045] The sideline evaluation tests of block  130  are followed by the more formal clinical tests of block  160 . The exemplary embodiment provides three separate tests to quantify damage or injury to each component of the balance system (the vestibular, the visual and somatosensory systems).  
     [0046] In block  164 , a hearing test is performed to evaluate the vestibular system. In particular an oto-acoustic emission test is performed. An oto-acoustic emission is a recordable sound generated by the inner ear, either spontaneously or in response to sound stimulation.  
     [0047] In block  168 , a dynamic vision test is performed to test the human vestibular ocular reflex. The vestibular ocular reflex maintains stable vision during head movement and is a manifestation of eye-head coordination. The dynamic vision test measures eye movement responsiveness to rapid head motions while the athlete attempts to focus on a static object. An instrument detects and records the movements of the eyes and the head. Examples of machines that test the vestibular ocular reflex include the Vorteq® from Micromedical Technologies, Inc.,™ and the VAT® from Western Systems Research, Inc.™ The resulting data establishes the gain (i.e., the overshoot or undershoot) and the latency of the vestibular ocular reflex in the athlete.  
     [0048] In block  172 , a balance test is performed to evaluate the coordination (or mismatch) between the vestibular system and the body&#39;s somasensatory system. When operating normally, the vestibular spinal reflex stabilizes the head and the body, and is manifested by movements of the skeleto-muscular system to maintain postural balance. There are a variety of different tests which may be used to test the vestibular spinal reflex, including moving platform posturagraphy which measures the relative movements of the ankles and hips of a person attempting to balance on a moving platform. Other vestibular spinal reflex tests evaluate posture, gait, sway and extremity drift. The vestibular spinal reflex test is useful in detecting dysfunctions involving the otolith organs, which provide inertial gravitational sensory data to the brain for maintaining balance.  
     [0049] The advanced evaluative process of this exemplary embodiment separately quantifies damage to each component of the balance system (the vestibular, visual, and somatosensory systems).  
     [0050] Although this exemplary embodiment provides for three initial assessment tests, five subjective sideline tests, five objective sideline tests, and three clinical evaluation tests, one or more of these particular tests may be omitted or substituted, and one or more other tests may be added, without detracting from many of the aspects of the present invention. Moreover, while the exemplary embodiment utilizes athletic terminology and customized tests for athletes performing in a contest, an equivalent procedure for assessing vestibular dysfunction may be applied to any individual suffering symptoms such as dizziness, nausea, imbalance, or cognitive difficulty without departing from many of the aspects of the present invention.  
     [0051]FIG. 2 is a functional flow diagram of one embodiment of a procedure for assessing and treating an athlete&#39;s balance system. In block  210 , an athlete who has just suffered a minor head injury, or who is due for a routine vestibular condition evaluation, is provided. In block  215 , an initial evaluation is performed on the athlete. This initial evaluation may comprise the tests discussed in FIG. 1. This preliminary evaluation may additionally comprise other tests such as pulse rate and blood temperature. If the athlete fails this initial evaluation, in block  255  the athlete is promptly referred for emergency medical treatment. If the athlete passes this initial evaluation, in block  220 , various sideline evaluation tests are performed. These sideline evaluation tests include a plurality of subjective and objective tests, such as those illustrated and described in FIG. 1. If the athlete passes these sideline evaluation tests, he or she is released to the team doctor for follow-up care, and is possibly returned to play. In block  230 , follow-up sideline testing is performed on the athlete over the next three days. If the athlete passes these tests for three consecutive days, in block  250 , the athlete is released.  
     [0052] If the athlete fails either the initial evaluation, the sideline evaluation, or the follow-up sideline testing, then in block  240 , a more in-depth clinical evaluation is administered. (If the athlete failed the initial evaluation, then the clinical evaluation is performed only if and after the athlete has been released from emergency medical treatment.) This clinical evaluation comprises a vestibular ocular reflex test and a vestibular spinal reflex test. This clinical evaluation may further comprise other tests, such as a hearing test or an oto-acoustic emission test.  
     [0053] If, in block  240 , the athlete passes the clinical evaluation, in block  260 , the athlete is given follow-up sideline testing. Else, in block  245 , the athlete is treated and retested every two days until his or her vestibular functioning is satisfactory. Once the athlete&#39;s vestibular performance is deemed satisfactory, and that performance is confirmed by follow-up sideline testing, then the athlete is released.  
     [0054] Of course, various functions illustrated and described in FIG. 2 may be modified, abbreviated, supplemented and to some extent even rearranged without detracting from many of the aspects of the present invention. Moreover, while this exemplary embodiment illustrates and describes the administration of a procedure to an athlete, an equivalent procedure would be useful to any patient suffering vestibular dysfunction. The procedure of the exemplary embodiment is useful not only for treating severe vestibular dysfunctions, but also for precisely calibrating a person&#39;s seemingly satisfactory vestibular system. Combined with the diagnostic procedures of the present invention, various training exercises can help refine and perfect the vestibular function of the body, giving the athlete a competitive edge.  
     [0055]FIG. 3 is a functional flow diagram of one embodiment of an administrative procedure for evaluating an athlete&#39;s vestibular functioning and for providing a treatment and research program. In block  310 , the athlete completes a form consenting to treatment or consenting to the use of the athlete&#39;s results for research purposes. In block  320 , the athlete completes a questionnaire. In the exemplary embodiment, the athlete accesses and complete both the consent form and questionnaire on-line from a computer connected to a global computer network.  
     [0056] In block  330 , the vestibular ocular and vestibular spinal reflexes of the athlete are tested. In the exemplary embodiment, these tests are performed at a sports health facility or an outpatient clinic by a clinician or athletic trainer. Machinery then records, in an electronically transferrable form, the vestibular ocular and vestibular spinal reflexes of the patient in response to various movements and stimuli.  
     [0057] In block  340 , an off-site physician retrieves and evaluates the patient questionnaire answers and the test results. Because the test results and questionnaire answers are recorded in electronically transferrable form, the tests do not have to be performed in the presence or at the location of a physician. Accordingly, in the exemplary embodiment, the questionnaire answers and test results are transmitted electronically over a computer network to a network-accessible database. Then the physician, at a time (within 24 hours of the test) and place convenient to the physician, retrieves and evaluates the test results, prescribing a recommended course of treatment.  
     [0058] In block  350 , the off-site physician relays, via the global computer network, his evaluation and treatment recommendation to the athletic trainer, physical therapist, coach, and team doctor. If, in block  360 , the test results are normal, then in block  365 , no further action is needed. Else, in block  370 , the team doctor, physical therapist, athletic trainer, and coach establish an appropriate treatment regimen for the athlete. In block  380 , the team doctor, physical therapist, athletic trainer, and coach regularly evaluate the athlete&#39;s progress.  
     [0059] Again, as with FIGS. 1 and 2, equivalent embodiments can help most persons, not just athletes, suffering vestibular abnormalities. Other aspects of the exemplary embodiment may be eliminated, modified, substituted, or supplemented, without detracting from many of the aspects of the present invention.  
     [0060]FIG. 4 is a functional flow diagram of one embodiment of a procedure for sideline evaluation of a person suffering from a central nervous abnormality, such as a recent head trauma. This embodiment, as applied to an athlete, permits one to objectively predict an athlete&#39;s concussional potential, and to predict whether it is safe for the athlete to return to play. Another benefit is that it allows an athletic trainer to make an accurate and immediate prediction of the athlete&#39;s potential for additional injury if he or she is returned to play.  
     [0061] In block  410 , the subject is observed for loss of consciousness. If the subject is not fully conscious, then a grade III concussion is likely, and, in block  450 , the subject is immediately referred to an emergency room. Else, in block  415 , up to five subjective sideline tests are administered. The subjective sideline tests comprise those discussed in FIG. 1 or their equivalents.  
     [0062] If, in block  420 , a subject fails two of these subjective sideline tests, then a grade three concussion is likely, and, in block  450 , the subject is immediately referred to an emergency room.  
     [0063] If, in block  425 , the subject has failed just one of the subjective sideline tests, then, in block  455 , the subject is removed from the contest. In block  460 , the test is repeated on the subject, and his or her condition reevaluated at regular intervals, or approximately every fifteen minutes. Additionally, the subject&#39;s blood pressure and heart rate are evaluated at regular intervals, or approximately every 15 minutes. If, in block  465 , the subject&#39;s condition declines, then a grade three concussion is likely and the subject is immediately referred to the emergency room.  
     [0064] If the subject has passed all of the subjective tests, then, in block  430 , one or more objective sideline tests are administered. If, in block  435 , the subject fails a Romberg sway test, then, as illustrated in block  455 , the subject is removed from the contest and, in block  460 , retested and reevaluated at regular intervals, or approximately every 15 minutes. Again, any decline in the subject&#39;s status counsels that the subject be referred to the emergency room immediately.  
     [0065] If, in block  440 , the subject passes all of the subjective sideline tests and the Romberg sway tests, but fails one or more of the other objective sideline tests, then, in block  470 , the subject is removed from the contest. In block  475 , these subjective tests are repeated after a brief interval of time, or approximately fifteen minutes. If, in block  480 , there is an improvement in those test results, then it is probable, as illustrated in block  485 , that the subject has merely suffered a grade-one concussion. Else, it is likely that the subject has suffered a grade-two concussion, and return to play is not advised.  
     [0066] If the subject passes all of the subjective and objective sideline tests, then the subject is cleared and returned to play in block  445 .  
     [0067] The advanced evaluative processes of the present invention integrate a plurality of diagnostic methods that permit an athletic or physical trainer to make a relatively accurate and immediate prediction of a subject&#39;s potential for additional injury, and whether the subject can return to play.  
     [0068] While particular embodiments of the invention have been illustrated and described, it will be obvious to those skilled in the art that various changes and modifications may be made without sacrificing the advantages provided by the methods and apparatuses disclosed herein.