By X. Gorok. Bellarmine University.
Decreased pin-prick sensation over the lateral deltoid ear discount zanaflex 2 mg visa, there is no response to the cold caloric buy zanaflex 2 mg mastercard. A 49-year-old man is admitted to the hospital with a least the past 9 months and are getting progressively worse generic zanaflex 2mg with visa. He does not have a history of seizures and he cur- She has great difﬁculty walking from the waiting room to rently takes no medications trusted zanaflex 2 mg. On most notable for small, shoddy lymphadenopathy in the physical examination, her cranial nerves are intact, and cervical region. A lumbar puncture shows no white or red blood cells, Light touch sensation is normal, and she is not orthostatic. Which of the following is the best course Which test is most likely to reveal the correct diagnosis? The patient in the preceding scenario returns for re- disease presents after an embolic cerebrovascular accident evaluation after 2 weeks of appropriate therapy. She lesion has not changed in size, and he has not had any describes the pain as burning as if she had been bathed in more seizures. His only complaint is a mild, but persistent, dif- double vision for the last 3 weeks. There is no history of head trauma, prior change in her speech, and her friends tell her that she is neurologic or psychiatric disease, or family history of de- “more nasal. Physical examination is only notable for a mod- ance and difﬁculty lifting objects and getting out of a erate cognitive deﬁcit with a mini-mental examination of chair. A 49-year-old woman presents for a second opinion regarding symptoms of tremors, difﬁculty with ambula- tion, and periodic ﬂushing. At that time, she was hospitalized for a synco- pal episode, after which she was told to increase her salt in- take. Since then, she has had progressive motor difﬁculties including bilateral tremors and a stiff slow gait. Chronic subdural hematoma Despite increasing doses, she does not feel improved, but E. Normal-pressure hydrocephalus rather has recently noticed uncontrollable movements that she describes at tics of her face. You are evaluating a patient who complains of ver- tory is recent recurrent urinary tract infections. The patient complains of seeing the room spin and cations are ropinirole, 24 mg daily, and nitrofurantoin, 100 feeling faint with certain head movements to the left. On physical your ofﬁce, you perform provocative maneuvers to differ- examination, her blood pressure is 130/70 mmHg with a entiate the cause of this patient’s vertigo. Which of the following ﬁndings would be suggestive of a She has recurrent motor movements of the right side of her central positional vertigo? Her neurologic examination shows increased muscle tone in the lower extremities with bilateral 4-Hz tremor. Lessening of symptoms with repeated trials has hyperesthesia in her arms in the area of her deltoids, D. Increased severity of symptoms with provocative testing but otherwise sensation is normal. A 65-year-old man presents to your ofﬁce com- tially, but it improves with encouragement. He has difﬁculty rising to a standing posi- muscles shows joint degeneration and a partial rotator tion and states that he shufﬂes when he walks. Endomysial deposits of amyloid when not moving but states there are times when he B. Scattered inﬂammatory foci surrounding muscle ﬁbers longer because of his motor symptoms. Which of the following criteria suggests the diagno- voice, or memory difﬁculties. Deep-seated steady facial pain ezetimibe, 10 mg daily, and lovastatin, 40 mg daily. Imaging of the lateral recesses of the spinal canal about the clinical course and treatment of Parkinson’s disease? Early initiation of therapy with levodopa predis- poses an individual to a higher likelihood of dyski- A. A 45-year-old woman presents for evaluation of a pramipexole is likely to be effective in controlling tingling sensation in her feet that has become more ap- his motor symptoms for 1–3 years before the addi- parent over the past 5 months. His family’s description suggests a simple partial comes into your ofﬁce for an acute visit. He has had back- seizure involving the left hand that spread to involve the ache for a few weeks that has improved with ibuprofen but entire arm. He was brought has developed right lower abdominal pain and inguinal in 2 h after symptom onset and is currently awake, alert, pain. He has not had any further seizures but has lower thoracic spinous processes and hyperesthesia in the been unable to move his left hand since his seizure. Strength is normal in the up- electrolytes and complete blood count are within normal per extremities, but he has symmetric weakness in the limits. He also has decreased On examination, sensation is intact in the affected limb sensation below the T11 distribution symmetrically. What but his strength is 0 out of 5 in the musculature of the left is the next step in the management of this patient? A 78-year-old man with diabetes mellitus presents using keys to open doors about 2 years ago. On physical treated empirically with nonsteroidal anti-inﬂammatory exam his temperature is 40. His neck is stiff and he has His symptoms have slowly progressed to the point where photophobia. He avoids going shows 2100 cells/µL, with 100% neutrophils, glucose 10 outside because of frequent falls. Dexamethasone after antibiotics chair, but the Romberg test is not able to be performed C. Eosinophilic myofasciitis ing college, and she has always attributed her headaches to C. She also had weakness in the extraocular muscles, aches occur about seven times monthly. She estimates that which is described to you as “googly eyes” with repeat ex- the headaches occur >90% of the time on the right side and aminations. She has no aura before the onset double vision almost exclusively when she watches televi- of a headache but describes occasional visual disturbance sion in the evening. The she frequently develops sensitivity of her scalp on the side patient denies any other past medical history and has a of the headache with associated paresthesias. Formal psychiatric evaluation vertigo that resolved over the course of several hours in as- B. Serum anti-acetylcholine receptor antibodies work because of headache, but feels like her productivity is D. Slit-lamp examination aches include red wine and aged cheese, which she has restricted from her diet for this reason. A 37-year-old man is witnessed by his family to have minophen, and naprosyn sodium have no effect on the du- a generalized tonic-clonic seizure at a party. Physical exam- for a maternal aunt with classic migraine headaches with ination shows no skin abnormalities and no stigmata of aura. The physical examination is normal without any evi- chronic liver or renal disease. His white What is the most appropriate next step in evaluation and blood cell count is 19,000/µL, hematocrit 36%, and plate- management of this patient? Which next step is most appropriate in this cluding consistent sleep-wake cycle and regular ex- patient’s management? Which of the following cranial nerve physical exam- from the female parent except ination techniques represents the correct approach to the patient with suspected neurologic disease? Trigeminal nerve: Examine the motor territories on head-on motor vehicle collision. The patient is unrespon- each side of the face by testing jaw clench, eyebrow sive even to painful stimuli and is apneic; however, he elevation and forehead wrinkling. Accessory nerve: Check shoulder shrug and head ro- would exclude a diagnosis of brain death? Cardiovascular, gastrointestinal, and skin examina- reddening of the right eye as well as nasal stufﬁness.
The danger of a tooth ankylosing in an intruded position should always be borne in mind and in this respect active treatment is preferable to a conservative approach purchase zanaflex 2mg. Elective pulp extirpation will be necessary for all significant intrusive luxation injuries in closed apex teeth (Table 12 buy zanaflex 2 mg low price. Maintain non-setting calcium hydroxide in root canal during orthodontic movement before obturation with gutta percha (Fig buy 2 mg zanaflex with mastercard. At the initial examination both open and closed apex teeth should receive antibiotics zanaflex 2 mg low cost, chlorhexidine mouthwash, and a soft diet. The risk of pulpal necrosis in these injuries is high, especially in the closed apex (Table 12. Avulsion and replantation Replantation should nearly always be attempted even though it may offer only a temporary solution due to the frequent occurrence of external inflammatory resorption (e. Even when resorption occurs the tooth may be retained for years acting as a natural space maintainer and preserving the height and width of the alveolus to facilitate later implant placement. Successful healing after replantation can only occur if there is minimal damage to the pulp and the p. Understandably non-dentists may be unhappy to replant the tooth and milk is an effective iso-osmolar medium. Endodontics⎯commence prior to splint removal for categories (b) and (c): (a) open apex. If resorption is progressing unhalted keep non-setting calcium hydroxide in the tooth until exfoliation, changing it 6 monthly. However, these teeth require regular clinical and radiographic review because once e. Replantation of teeth with a dry storage time of greater than 1 h The consenus opinion is that teeth with very immature apices should not be replanted. The incidence of resorption, ankylosis, and subsequent loss is high due to the high rate of bone remodelling in this age group. The root canal is then obturated with gutta percha and the tooth replanted and splinted for a longer period of up to 6 weeks. The aim of this treatment is to produce ankylosis allowing the tooth to be maintained as a natural space maintainer, perhaps for a limited period only. Immature teeth have a better prognosis than mature teeth due to the wide apical opening where slight movements can occur without disruption of the apical neurovascular bundle. Necrosis can be diagnosed in most cases within 3 months of injury but in some cases may not be evident for at least 2 years. A combination of clinical and radiological signs are often required to diagnose necrosis. Most pulps that recover test positively within months but responses have been reported as late as 2 years after injury. Postpone endodontics until at least one other clinical and/or radiographic sign is present. A grey colour that appears for the first time several weeks or months after trauma, signifies decomposition of necrotic pulp tissue and is a decisive sign of necrosis. Colour changes are usually most apparent on the palatal surface of the injured teeth. In an injured pulp necrosis may progress from coronal to apical portion and hence residual apical vitality may result in formation of a calcific barrier across a wide apical foramen. Failure of the pulp chamber and root canal to mature and reduce in size on successive radiographs compared with contralateral uninjured teeth is also a reliable indicator of necrosis. Primary teeth which develop pathological resorptive lesions are not good candidates for conservative treatment and should be extracted. Permanent teeth on the other hand may often be successfully treated provided tissue destruction has not advanced to an unrestorable state. Two general forms of pathological root resorption are recognized, inflammatory and replacement. If giant cells are continuously stimulated, most commonly by microbial products from an infected root canal or periodontal pocket, progressive inflammatory root resorption may follow with catastrophic consequences. Inflammatory root resorption may be classified according to its site of origin as external root resorption, cervical resorption (a special form of external resorption), or internal root resorption. However, if the infected canal contents are removed, the propagating stimulus is lost and the lesion will predictably arrest. Sometimes it may present as a radiolucency overlying the root, and can be distinguished from internal resorption by its asymmetrical shape, by the superimposed contour of the intact root canal walls, and by the fact that it moves in relation to the root canal on periapical films of different horizontal angle. Provided the tooth is still restorable, external inflammatory root resorption should be treated without delay. Following access cavity preparation, the root canal should be cleaned and shaped, taking care not to weaken the root excessively, or to risk perforation into the resorbed area. It is common practice to dress the root canal with non-setting calcium hydroxide paste and to monitor the tooth for several months prior to definitive obturation to ensure that the lesion has arrested. Nevertheless, control of intracanal infection is the key determinant of success, and there is good evidence to suggest that if the canal is adequately prepared, it may be filled without protracted calcium hydroxide treatment. From a very small entry point, the resorptive process may extend widely before penetrating the pulp chamber (Fig. Extensive intracoronal extension may occasionally present cervical resorption as a clinically visible pink spot. More commonly, it is identified on routine radiographs as a characteristically sited radiolucency (Fig. If the tooth is non-vital, conventional root canal therapy should be undertaken to eliminate the propagating stimulus. Arrangements should then be made to open the resorptive defect in a similar manner to cavity preparation, and to curette away all traces of inflammatory tissue before restoring the resultant defect (Fig. Often, a flap must be raised to adequately eliminate resorptive tissue and contour the subgingival restoration. If the tooth is vital, and the pulp has not been invaded, treatment may be limited to opening and curetting the resorption lacuna before placing a setting calcium hydroxide lining and restoring the defect with an appropriate material. Infected material in the non-vital, coronal part of the canal is believed to propagate resorption by the underlying vital tissue, and rapid tissue destruction follows. Large resorptive defects affecting the coronal third of the canal may present as a pink discoloration of the affected tooth. More commonly, it is detected as a chance finding on routine radiographic examination. Radiographically, internal resorption presents as a rounded, symmetrical radiolucency, centred on the root canal. Internal resorption should be considered to be a form of irreversible pulpitis and treated without delay. Following standard access cavity preparation, the pulp chamber and coronal portion of the canal is usually found to contain necrotic debris. However, deeper penetration of the canal often provokes torrential haemorrhage as the vascular, resorptive tissue is entered. Root canal preparation is undertaken in the usual manner, and following apical enlargement, haemorrhage from the canal is greatly reduced as the blood supply to the resorptive tissue is severed. Instrumentation of the expanded, resorbed area is difficult, and can be greatly enhanced by the use of sonic or ultrasonic devices which are able to throw irrigant into uninstrumented areas. The antimicrobial and tissue solvent actions of sodium hypochlorite make it the irrigant of choice in such cases. As in the case of external inflammatory resorption, it is usual to dress the canal with non-setting calcium hydroxide following debridement. This may be highly advantageous in the internal resorption case where the antimicrobial and mild tissue solvent actions of calcium hydroxide may be exploited further to clean the resorbed area. Obturation may then be undertaken with gutta percha and sealer, usually employing a thermoplastic technique to allow satisfactory condensation and adaptation in the resorbed area (Fig. Where internal reinforcement is indicated, dual curing composite resin and fibre posts may offer some advantages over full canal filling with gutta percha and sealer. If more than 20% of the periodontal ligament is damaged or lost and the tooth is subsequently reimplanted, bone cells are able to grow into contact with the root surface more quickly than the remaining periodontal fibroblasts are able to recolonize the root surface and intervene between tooth and bone. The consequence is that the root now becomes involved in the normal remodelling process of the bone in which it is implanted, and is gradually replaced by bone over the course of the following years. In young children where the rate of bone remodelling is high, the root may be entirely lost within 3-4 years. The absence of a ligamentous joint between the tooth and its supporting bone (ankylosis) means that even when root resorption is advanced, the tooth will appear rock solid. Radiographically, the root will appear ragged in outline, with no obvious periodontal ligament space separating it from the surrounding bone (Fig.
In such cases purchase 2 mg zanaflex, round to the nearest value in the z-table or buy zanaflex 2 mg amex, to compute the precise value 2 mg zanaflex mastercard, perform “linear interpola- tion” (described in Appendix A discount zanaflex 2 mg mastercard. For example, say that we want to examine Bucky’s raw score, which transforms into the positive z-score of 11. If we seek the proportion of scores above his score, then from column C we expect that. If we seek the relative frequency of scores between his score and the mean, from column B we expect that. What is the relative frequency of scores ■ To find the raw score at a specified relative below 59? To find the score above the mean with 15% of the scores between it and the mean (or the score at the 65th percentile): From column B, the pro- portion closest to. Often, however, test results are also shared with people who do not understand z-scores; imagine someone learning that he or she has a negative personality score! To eliminate negative scores and decimals, sub-test scores are transformed so that the mean is about 500 and the standard deviation is about 100. When debating such issues as what a genius is or how to define “abnormal,” researchers often rely on relative standing. For example, the term “genius” might be defined as scoring above a z of 2 on an intel- ligence test. We’ve seen that only about 2% of any distribution is above this score, so we have defined genius as being in the top 2% on the intelligence test. Or, “abnormal” might be defined as having a z-score below 2 on a personality inventory. Such scores are statistically abnormal because they are very infrequent, extremely low scores. If the instructor defines A students as the top 2%, then students with z-scores greater than 2 receive As. If B students are the next 13%, then students having z-scores between 1 and 2 receive Bs, and so on. This procedure is very important because all inferential statistics involve computing something like a z-score for our sample data. We’ll elaborate on this procedure in later chapters but, for now, simply understand how to compute a z-score for a sample mean and then apply the standard normal curve model. The problem is the same as when we examined individ- ual raw scores: Without a frame of reference, we don’t know whether a particular sample mean is high, low, or in-between. Previously, a z-score compared a particular raw score to the other scores that occur in this situa- tion. Now we’ll compare our sample mean to the other sample means that occur in this situation. Therefore, the first step is to take a small detour and create a distribu- tion showing these other means. To evaluate our sample mean, we first create a distribution showing all other pos- sible means we might have obtained. So that we can see all possible sample means that might occur the stat- istician would sample the population an infinite number of times: She would randomly select a sample with the same size N as ours (25), compute the sample mean, replace the scores in the hat, draw another 25 scores, compute the mean, and so on. At other times, a sample would contain too many low scores and not enough high scores, so the mean would be below 500 to some degree. Therefore, over Using z-Scores to Describe Sample Means 125 the long run, the statistician would obtain many different sample means. To see them all, she would create a frequency polygon, which is called the sampling distribution of means. The sampling distribution of means is the frequency distribution of all possi- ble sample means that occur when an infinite number of samples of the same size N are randomly selected from one raw score population. This is similar to a distribution of raw scores, except that here each score on the X axis is a sample mean. To the right of are the sample means the statistician obtained that are greater than 500, and to the left of are the sample means that were less than 500. This is because most scores in the population are close to 500, so most of the time the statistician will get a sample containing scores that are close to 500, so the sample mean will be close to 500. Less frequently, the statistician will obtain a strange sample containing mainly scores that are farther below or above 500, producing means that are farther below or above 500. Once in a great while, some very unusual samples will be drawn, resulting in sam- ple means that deviate greatly from 500. The story about the bored statistician is useful because it helps you to understand what a sampling distribution is. The central limit theorem is a statistical principle that defines the mean, the standard deviation, and the shape of a sampling distribution. From the central limit theorem, we know that the sampling distribution of means always (1) forms an approximately normal distribution, (2) has a equal to the of the underlying raw score population from which the sampling distribution was created, and (3), as you’ll see shortly, has a standard deviation that is mathematically related to the standard deviation of the raw score population. The importance of the central limit theorem is that with it we can describe the sam- pling distribution from any variable without actually having to infinitely sample the population of raw scores. Then we’ll know the important characteristics of the sampling distribution of means. Remember that we took a small detour, but the original problem was to evaluate our Prunepit mean of 520. To do so, we simply determine where a mean of 520 falls on the X axis of the sampling distribution in Figure 6. But if 520 lies toward the tail of the distribution, far from 500, then it is a more infrequent and unusual sample mean (the statistician seldom found such a mean). The sampling distribution is a normal distribution, and you already know how to determine the location of any “score” on a normal distribution: We use—you guessed it—z-scores. That is, we determine how far the sample mean is from the mean of the sampling distribution when measured using the standard deviation of the distribution. This will tell us the sample mean’s relative standing among all possible means that occur in this situation. To calculate the z-score for a sample mean, we need one more piece of information: the standard deviation of the sampling distribution. The Standard Error of the Mean The standard deviation of the sampling distribution of means is called the standard error of the mean. That is, in some sampling distributions, the sample means may be very different from one another and, “on average,” deviate greatly from the average sample mean. For the moment, we’ll discuss the true standard error of the mean, as if we had actually computed it using the entire sampling distribution. The σ indicates that we are describing a population, but the subscript X indicates that we are describing a population of sample means—what we call the sampling dis- tribution of means. The central limit theorem tells us that σX can be found using the following formula: The formula for the true standard error of the mean is σX σX 5 1N Using z-Scores to Describe Sample Means 127 Notice that the formula involves σX, the true standard deviation of the underlying raw score population, and N, our sample size. This is because with more variable raw scores the statistician often gets a very different set of scores from one sample to the next, so the sample means will be very different (and σX will be larger). But, if the raw scores are not so variable, then different samples will tend to contain the same scores, and so the means will be similar (and σX will be smaller). With a very small N (say 2), it is easy for each sample to be different from the next, so the sample means will differ (and σX will be larger). How- ever, with a large N, each sample will be more like the population, so all sample means will be closer to the population mean (and σX will be smaller). This is because the bored statisti- cian will often encounter a variety of high and low scores in each sample, but they will usually balance out to produce means at or close to 500. Therefore, the sample means will not be as spread out around 500 as the individual scores are. Likewise, every sampling dis- tribution is less spread out than the underlying raw score population used to create it. Computing a z-Score for a Sample Mean We use this formula to compute a z-score for a sample mean: The formula for the transforming a sample mean into a z-score is X 2 z 5 σX In the formula, X stands for our sample mean, stands for the mean of the sampling distribution (which equals the mean of the underlying raw score population) and σX stands for the standard error of the mean. Here, however, we are measuring how far the sample mean score is from the mean of the sampling distribution, measured using the “standard devi- ation” called the standard error. For the sample from Prunepit U, X 5 520, 5 500, and σX 5 20, so X 2 520 2 500 120 z 5 5 5 511.