The thumb can be opposed with any of the four other digits depending on the shape of the object to be held and the type of manipulation required generic fildena 25 mg online. However buy fildena with a mastercard, there are subtler or less easily delineated patterns of symptoms in the hand discount fildena 100mg amex, particularly when pain is diffuse or poorly localized purchase fildena 150 mg free shipping. Are there neurologic qualities to the pain or characteristics typical of a common nerve lesion? Ask about occupation and other activities that are associated with neck problems, the relationship with sleep posture, and frequent headaches. However, pain in this condition is often poorly localized at initial presentation. Tingling/pins and needles/numbness Make sure both you and the patient understand what you each mean by these terms: • Symptoms usually denote cervical nerve root or peripheral nerve compression, although they can reflect underlying ischaemia. Pain arising from bone Pain in the hands arising from bones may be difficult to discriminate. Radiographs will often lead to confirmation of the diagnosis: • The most common tumour in the hand is an enchondroma. A history suggestive of ischaemic pain in the hands is rare in rheumatologic practice. Persistent ischaemic digital pain can complicate systemic sclerosis and severe Raynaud’s (see Chapter 13): • Digital vasomotor instability (e. Patients with carpal tunnel syndrome, for example, can complain of the hand swelling at night. This most commonly affects the middle and ring fingers, and is prevalent among professional drivers, cyclists, and those in occupations requiring repeated use of hand-held heavy machinery. Examination of the hand: adults The following sequence is comprehensive, but should be considered if a general condition is suspected. Inspection of the nails and fingers • Pits/ridges and dactylitis are associated with psoriatic arthritis (see Plate 8 and Chapter 8). The skin may be initially puffy, but later shiny and tight and, with progression, atrophic with contractures. Note any deformity of digits • Deformities tend to occur with long-standing polyarticular joint disease, e. Inspect the palm and dorsum of the hand • Palmar erythema is not specific, but is associated with autoimmune disorders of connective tissue and joints. Palpation of joints and nodules Palpation of joints and nodules is best done using thumb pads with the patient’s wrist supported: • Swelling should be noted for site, consistency, tenderness, and mobility. Osteophytes and exostosis are periarticular or at sites of pressure, may be tender, but are always fixed (see Plate 7d). Palpate tendons in the palm or on the volar aspect of the phalanges • Thickening, tenderness, and crepitus suggest tenosynovitis, but tenosynovitis can be hard to spot if it is mild. Discriminate Dupuytren’s disease from flexor tendinopathy Dupuytren’s disease (a fascia contracture) typically involves the fourth and fifth fingers (40% bilateral). It is associated with epilepsy, diabetes, and alcoholism, and usually is not painful. Tc- labelled human immunoglobulin is more specific for detecting patterns of synovitis in children and adults. Management of the soft tissue lesions in the hand and wrist, like elsewhere, combines periods of rest and splinting with active physical therapy, avoidance of repetitive activity, and analgesia. In most cases, the condition will resolve spontaneously, but severe or persistent pain and disability may warrant input from a hand occupational therapist, local steroid injections, or occasionally surgical soft tissue decompression: • Conditions that respond to local steroid therapy (see Chapter 24): • tenosynovitis, e. Early use of splints, orthotics, and exercises may lead to greater functional ability and a decrease in symptoms. Upper limb peripheral nerve lesions Background • Upper limb peripheral nerve lesions are common. Occasionally, nerve trauma may present to primary care providers or rheumatologists with (primarily) regional muscle weakness. Features may be considered more specific for nerve entrapment if there is a history of acute or overuse trauma proximal to the distribution of the symptoms. Useful in this respect is knowledge of likely sites of entrapment or damage and, in the case of entrapment, the ability to elicit a positive Hoffman–Tinel sign (i. It should not be relied on to make a diagnosis in the absence of good clinical assessment. The long thoracic nerve • Entrapment is in the differential diagnosis of painless shoulder weakness. The nerve origin is at C5–C7, and its course runs beneath the subscapularis and into the serratus anterior. Winging is demonstrated by inspection from behind with the patient pressing against a wall with an outstretched arm. The suprascapular nerve • The nerve origin is at roots C4–C6; its course is lateral and deep to the trapezius, through the suprascapular notch, terminating in the supraspinatus and posteriorly in the infraspinatus. Weightlifters are prone to bilateral injury and volleyball players prone to dominant side injury. It lies along the medial side of the brachial artery in the upper arm, then above the medial humeral epicondyle where it passes posteriorly, piercing the medial intermuscular septum. It then runs behind the elbow in a groove between the olecranon and medial epicondyle, covered by a fibrous sheath and arcuate ligament (cubital tunnel). The nerve enters the hand on the ulnar side dividing into superficial (palmaris brevis and skin over the medial one and a half digits) and deep (small muscles of the hand) branches: • Lesions are usually due to entrapment. The Tinel test at the elbow may be positive and there might be sensory loss over the palmar aspect of the fifth digit. External compression, acute or recurrent trauma, and ganglia are the usual causes. Symptoms have been noted in cyclists, users of pneumatic or vibrating tools and in avid videogame players. Entrapment of the purely sensory cutaneous branch can occur from excess computer mouse use. A review of posture, repetitive activity, and a biomechanical assessment with changes in activities and technique are recommended. Radial nerve The nerve origin is at roots C5–C8, and its course runs anterior to subscapularis then passes behind the humerus in a groove that runs between the long and medial heads of triceps. It then winds anteriorly around the humeral shaft to lie between brachialis and brachioradialis. The triceps is usually unaffected as the nerve supply to the muscle leaves the radial nerve proximally. Its course from the brachial plexus runs together with the brachial artery in the upper arm (supplying nothing) then enters the forearm between the two heads of pronator teres (from medial humeral epicondyle and coronoid process of the ulna). It runs deep in the forearm dividing into median and anterior interosseous branches. The median branch enters the hand beneath the flexor retinaculum on the radial side of the wrist. There is local tenderness and reproduction of pain from resisted forearm pronation or wrist flexion. If partial remission is achieved, consider repeating the injection (see Chapter 24). Reconsider also whether there really is a mechanical/local or perhaps a subtler cause (e. Approximate area of sensory change in lesions of the median (c) and ulnar (d) nerves. Thoracic back and chest pain in adults Background • The thoracic segment (T1–T12) moves less than the lumbar and cervical spine. However, given the number of segments this can add up to appreciable mobility overall. Less segmental movement results in reduced frequency of problems overall (only 6% of patients attending a spinal clinic have thoracic spine problems). However, up to five nerve roots may contribute innervation of any one point in a truncal dermatome. Squeezing, strangling, or constriction in chest, can be aching or burning in nature. Commonly substernal, but radiates to any of anterior chest, interscapular area, arms (mainly left), shoulders, teeth, and abdomen.
The best action to take to ensure patient safety in the event of a tissue recall is to take which of the following actions? Record the fnal disposition in your log and with the supplier as wasted/discarded B buy cheap fildena 150mg on-line. Record the fnal disposition in your log and with the supplier as implanted in the patient C order fildena paypal. Record the fnal disposition in your log as wasted/discarded but inform the supplier at the monthly audit that the graft could have been implanted D discount fildena 150mg free shipping. Record the fnal disposition in your log and with the supplier as unaccounted for E order fildena 100 mg on line. Do not record a fnal disposition in your log or notify the supplier Concept: Biovigilance is a process used to ensure the safety of tissue recipients. In order for the notifcation of the recipient to occur, all tissues must be traceable from the donor to the recipient and vice versa. Answer: B—Even if it is not possible to make a defnite connection between the donor and the tissue, it is safer to err on the side of caution and track the graft as being possibly implanted in the patient so the patient can be contacted in the event of a potential recall. The other choices (Answers A, C, D, and E) do not represent good practice for documentation of the disposition of the tissue. Your facility receives a replacement graft for the tissues that the surgeon used from the spacer set, and the expiration date indicated on the packing slip does not match the expiration date on the tissue label. Accept the allograft and log the expiration date from the package label in your records B. Modify the package label to match the expiration date recorded on the packing list D. Finally, the tissue service must verify that package labels are complete, affxed, and legible. Accurate expiration dates must be available to assure that tissues are not used past the expiration date established by the tissue processor. It is not necessary to discard or reject the tissue if the distributor can provide written evidence of the correct expiration date (Answers A and D). If the discrepancy cannot be resolved, the tissue should be returned to the distributor (Answers C and E). The room temperature for allograft storage in your facility often fuctuates outside of this range. In order to meet the standards for tissue storage and provide optimal patient care you should do which of the following? Locate a device within your facility for tissue storage that can be maintained at 20–25°C B. Leave the tissues in the current storage area, but monitor and note the temperature deviations and determine if there was a signifcant risk to the tissue C. Ask the surgeon to sign a variance agreeing to use the tissue for a nonemergent surgery with knowledge of the out-of-range temperature storage Concept: Hospital tissue services are required to follow the tissue processor’s instructions for storage requirements that are listed in the package insert accompanying the tissue. Tissue storage equipment should be validated to be able to maintain desired temperatures and should have functional alarms. Answer: A—The facility should make every effort to fnd an appropriate storage device before simply refusing to all the tissue to be used (Answer D). While monitoring temperatures and documenting excursions to defned temperature ranges is required, continuing to store tissues in areas that do not routinely meet established storage temperatures does not meet the standard 444 18. The surgeon should not be put in a position to sign for tissue stored outside of recommended temperature ranges (Answer E). A month after the procedure, the supplier of the grafts informs you that three grafts that were consigned to your service have been recalled. Which of the following is the frst step that should be taken by your tissue service? Generate a list of recipients of recalled tissue Concept: Tissue recalls can occur for many reasons, of varying risk to the tissue or the recipient of the tissue. It is important to have a stepwise process in place for responding to recalls, and a robust tissue tracking system to identify the location and/or disposition of recalled tissue. Answer: D—Until a determination can be made about the implications of a recall, tissue that is in inventory should be quarantined. Further investigation may (rarely) allow the tissue to be subsequently released for the implantation. The tissue tracking system should allow identifcation of all individuals who received the tissue(s) (Answers B and E), and in consultation with the surgeon who implanted the tissue (Answer A), individual risk assessment should be conducted. The patients can then be contacted if additional testing or counseling is deemed appropriate (Answer C). Eastlund, Bacterial infection transmitted by human allograft transplantation, Cell Tissue Bank 7 (2006) 147–166. The need to process and store large amounts of data has been a driving force in the development of pathology informatics as a recognized pathology subspecialty. This chapter will provide a review of pathology informatics that is relevant to the practice of transfusion medicine, apher- esis, and hemostasis. It is used for storing information, and can have a value of true or false, or off and on. It is typically represented by the values of 0 (for false or off) or 1 (for true or on). This defnition of a kilobyte is derived from the equation 1 10 kilobyte = 2 bytes. This usage originated for multiples that needed to be expressed in powers of 2, but lacked a convenient unit prefx. In terms of information systems and computer networks, which of the following is the best description of a “client”? A device and/or software that inspects the network traffc that passes through it, and denies or permits passage of that traffc based on a set of predetermined rules B. A device or software that accepts connections to service requests by sending back responses E. A device that modulates an analog carrier signal to encode digital information Concept: Networks are made up of various components, each of which has a defned function or purpose. Once the client request has been fulflled, the connection to the server is terminated. A device or software package that inspects network traffc passing through it and denies or permits passage based on a set of predetermined rules is a frewall (Answer A). A router routes or forwards information to the appropriate location on the network (Answer B). A server is a device or software that accepts connections to service requests by sending back responses (Answer D). Finally, a device that modulates an analog carrier signal to encode digital information is a modem (Answer E). It can be defned as a collection of data organized into a structural database architecture. Answer: C—The interface type shown in the image is a query bidirectional interface. A query bidirectional interface is typically used with bar-coded labeled specimens. The analyzer then queries the host, requesting all of the information associated with the test. The key here is to note that the clinical instrument sends a test query to the information system, while the information system also queries the analyzer for additional test requests. Results are ultimately sent to the information system and then reports are generated. Bidirectional interfaces are usually found on instruments that can perform a wide variety of tests on each specimen. In this type of interface, the host downloads information to the interface subsystem in advance and stores the downloaded information into access memory. This action speeds up the query process because the interface is able to quickly respond due to having already downloaded critical information for the laboratory test (Fig. Of the following choices, which would be the frst step when deciding whether to purchase new hardware or software for the blood bank? Determine your desired functional requirements for the new hardware or software D. Generate a unique identifer so that the new hardware or software can communicate with outside systems Concept: One of the frst steps in acquiring new hardware or software for any laboratory information system is determining the functional requirements—what tasks or goals the software is supposed to accomplish. Answer: C—Of the choices offered, this choice would be the frst step in the implementation of new hardware or software.
It has been shown that the amount of coro- nary artery calcium refects the total atherosclerotic bur- den buy 100 mg fildena with mastercard, including both calcifed and noncalcifed plaques cheap fildena 100mg mastercard. The coronary artery calcium order fildena 50mg online, the area and density order 150 mg fildena, volume, or pericardium is visible as a thin line (arrowhead ). Panel A shows the apical infarction with thinning and fatty degeneration of the myocardium (arrow), while a nearby calci- ﬁcation is also visible on a four-chamber view reconstructed from the non-contrast acquisition (arrowhead ). Scientifc evi- >1,000 Extensive dence is not sufcient to validate a new Hounsfeld unit The thresholds shown here are empirical threshold or scoring system for 100 or 80 kV, and each scanner is expected to have some variation, so it is rec- ommended to acquire coronary artery calcium scans methods exist: (1) the Agatston score (Tables 11. Such patient-specifc protocols and lim- increases with age, and both are higher in men compared ited scan lengths reduce radiation exposure. Images are although both scoring methods yielded efective risk reconstructed using a 512 × 512 matrix on a small feld of stratifcation, the absolute measurement approach per- 11 view (Chap. Other calcifed tissues including In asymptomatic individuals, the absence of detectable cardiac valve leafets can resemble coronary artery calcium coronary artery calcium is associated with a very low and must be interpreted correctly in order not to falsely (less than 1 % per year) risk of major cardiovascular increase the total “coronary” calcium score (Fig. At the other extreme, up to Misinterpretation is highly unlikely in experienced centers, an 11-fold higher risk for major cardiac events has been as these diferent entities are easy to distinguish from each reported for asymptomatic people with extensive coro- other. Importantly, aortic valve calcifcation has indepen- nary calcifcation (Agatston score >1,000), and results of dent prognostic value for risk stratifcation. It is important several large population-based studies provide evidence to distinguish all of these noncoronary fndings so that for the incremental prognostic value of coronary artery they can be properly diagnosed and managed. The population-based Multi-Ethnic Study of Atherosclerosis, conducted in 6,722 asymptomatic individuals from four racial groups 11. However, in individuals classifed as very low risk by the Framingham method (<6 % 10-year risk), high coronary artery calcium scores (Agatston score>400) are uncommon, and despite increased risk, this segment of the population remains below the cur- rent risk threshold for aggressive risk factor modifca- tion. Several studies have shown the prognostic value of coronary calcium scoring for people with a low to moder- ate risk. Francis Heart Study demonstrated that low-risk patients, especially those in middle age, can have increased cardiovascular risk associated with very high coronary calcium scores. This is important to distinguish from the sonnel who had very high coronary calcium scores. Tus, calciﬁcation (arrowhead) in left circumﬂex artery, as this would the American College of Cardiology and American Heart substantially increase the coronary calcium score. In this population sample, participants with an estimated baseline Framingham risk of 16–20 % who also had a calcium score of at least 301 Agatston units were reclassiﬁed to a much higher risk group. Note that thresholds of 100 and 400 for the Agatston score have been most widely used in clinical practice. Very few studies have utilized alternative thresholds, such as 300 or 600, and these alternative thresholds are not generally clinically employed (With permission from Greenland et al. In persons with an intermediate lism as well as use and dose of calcium-based phosphate risk (>10–20 % 10-year risk), coronary artery calcium binders. In addition to the amount of coronary calcium, scoring has been shown to be the most useful additional calcifcation of the mitral annulus and noncoronary vas- risk marker for risk classifcation compared to other cular calcifcation in dialysis patients have also been markers such as carotid intima-media thickness and shown to be associated with incident cardiovascular C-reactive protein. Even in the Patients with any coronary artery calcium should switch absence of cardiac symptoms, type 2 diabetics are con- to non-calcium-based phosphate binders, so the calcium sidered at high risk for coronary artery disease, and sec- score can directly infuence clinical decision making. Coronary artery calcium scoring is not considered use- Further risk stratifcation in diabetic patients may help ful for cardiovascular risk stratifcation of patients with identify those with extensive coronary atherosclerosis chronic kidney disease, who are already considered can- and with signifcant inducible silent myocardial isch- didates for intensive cardiovascular risk modifcation. Coronary calcium scoring for risk stratifcation in asymptomatic diabetic patients is currently endorsed by 11. Data relating to asymptomatic diabetics for the presence of silent isch- coronary calcium progression demonstrate that, while emia is considered, preselection of individuals based on statins do not specifcally slow progression in short-term calcium scores >400 with the intent of performing sub- randomized trials of low-dose statins versus placebo, cal- sequent functional imaging if a substantial atheroscle- cifcation progression is consistently and strongly associ- rotic burden is identifed might be reasonable. Progression of the absolute calcium score is dependent Impaired renal function is a major cardiovascular risk on the amount of calcium present at baseline. It is also factor, and the risk gradually increases as the glomerular related to patient age, sex, family history of premature fltration rate decreases. Patients with impaired renal coronary artery disease, ethnic background, diabetes, function have elevated coronary artery calcium scores, body mass index, elevated blood pressure, and renal and the prevalence and extent of coronary calcium are insufciency. Importantly, the reliability of measurement 188 Chapter 11 ● Coronary Artery Calcium in repeat calcium scans is relatively high and may be 11. A large substudy of the T e Canadian Risk Assessment guideline was updated in Multi-Ethnic Study of Atherosclerosis showed a fourfold 2012 (published in 2013). The Guideline states: While increased risk in calcium score progressors versus non- not as sensitive as coronary angiography, coronary artery progressors, independent of statin use. Terefore, serial calcium scoring may be useful for the diferential diag- assessment may have value in assessing plaque progres- nosis of chest pain in highly selected patients. Coronary sion and identifying progressors, who are at increased artery calcium scoring, according to the Canadian risk of cardiovascular events. Practice guidelines from Guideline, is not recommended for screening asymp- several countries do not currently recommend using tomatic people. The Rotterdam calcifcation study showed that the upper percentile range refects a 12-fold increased risk of myo- 11. In addition, coronary cal- score greater than zero establishes the presence of under- cium scoring provides prognostic information in asymp- lying coronary artery disease and may be a rationale for tomatic type 2 diabetic patients without known coronary more aggressive risk factor management. Terefore, these specifc patient groups future events increases in direct proportion to the coro- may beneft from imaging strategies for risk stratifcation nary artery calcium score. Patients with diabetes and in primary prevention, and the use of coronary artery high coronary artery calcium scores may be candidates calcium scoring may be reasonable, afer consideration for cardiac stress testing to rule out the presence of silent of patient characteristics and the specifc clinical myocardial ischemia. Eur Heart J 29(18):2244–2251 Erbel R, Möhlenkamp S, Moebus S, Schmermund A, Lehmann N, Stang be at low to intermediate risk. Tus, calcium scoring A, Dragano N, Grönemeyer D, Seibel R, Kälsch H, Bröcker-Preuss has great potential for improving risk assessment. J Am Coll Perk J, De Backer G, Gohlke H et al (2012) European guidelines on car- Cardiol 53:345–352 diovascular disease prevention in clinical practice (version 2012). Eur J Cardiovasc Prev practice (constituted by representatives of nine societies and by Rehabil 16(5):541–549 invited experts). Eur Heart J 33:1635–1701 Coronary calcium score improves classifcation of coronary heart Rose G (1985) Sick individuals and sick populations. Moreover, in patients with coronary artery bypass Abstract grafs, the investigation of the native vessels can pose a challenge because of the ofen times severe coronary cal- This chapter provides practical information for optimiz- cifcations present. Reading the images is best done on axial and multiplanar reformations and should include the evaluation of graft anastomoses and run-oﬀs as 12. T ere are two main approaches for performing coronary artery bypass grafing: (1) traditional on-pump surgery, the most common form of revascularization, which usu- ally involves median sternotomy, a single period of aortic 12. This includes ing, recurrence of symptoms can be due to graf failure four subtypes: (a) port access coronary artery bypass or progression of atherosclerosis in the native vessels. The latest generation of scanners with a very the target vessel by specifc devices; and (d) minimally large detector coverage (320-row; Chap. For Depending on the approach used for revasculariza- clinical routine, at least 64 rows are recommended for 12 tion, the surgeon can utilize diferent types of arterial follow-up of patients afer coronary surgery. T e lef internal mammary artery is usually anasto- Patients who have received a mammary artery bypass mosed to the lef descending coronary artery, diagonals, graf should be scanned starting at the subclavian arteries and/or obtuse marginal branches both as a single graf (about at the middle of the clavicle, Chap. The right usually ends at the inferior border of the heart with the internal mammary artery is usually anastomosed to the exception of patients with a gastroepiploic artery graf, in lef anterior descending coronary artery crossing the whom the scan has to include the upper abdomen. An amount of approximately used as free graf to all coronary arteries as a single graf 60–100 ml of contrast agent followed by a saline fush is (Fig. For specifc recommenda- In case of a slow and stable heart rate (<65 beats per tions for scanners from diferent vendors see Chap. The assessability of the radial artery free graft is slightly impaired by the presence of the typical large number of metallic clips (Panel C , curved multiplanar reformation) 196 Chapter 12 ● Coronary Artery Bypass Grafts A ⊡ Fig. Diagnostic accuracy and evaluability depend on the technical characteristics of the scanner available with a continuous improvement of performance from 4-row to 64-row (or more) scanners. Volume-rendered images for a rapid overview of 38 % of the patent grafs could not be evaluated because graft anatomy of respiratory/motion/metallic clip artifacts. Evaluation of graft anastomoses and run-oﬀ assessable because of artifacts (Table 12. Anatomy of the thoracic aorta and left ventricle distal anastomosis and showed excellent diagnostic (diastolic dimensions) results (Table 12. Left ventricular and valve function in case of retro- venous grafs without excluding grafs from analysis. Numbers in parentheses are 95 % conﬁdence intervals segments being nondiagnostic, mostly because of severe Hamon M, Lepage O, Malagutti P et al (2008) Diagnostic performance of calcifcations. Radiology 247:679–686 sitivity and specifcity are signifcantly lower than in Hermann F, Martinof S, Meyer T et al (2008) Reduction of radiation esti- patients with suspected coronary artery disease.
Lingual Nerve off the many small dental branches that spread through trabecular (spongy) bone of the mandible in order to The next branch of the mandibular nerve order fildena 25mg mastercard, given off enter the apical foramen of all mandibular molars and inferior to the foramen ovale cheap fildena online master card, is the lingual nerve premolars buy fildena once a day. It also innervates the periodontal ligaments branch that goes to the tongue (Figs purchase fildena us. While within the It passes downward, medial to the ramus but lateral to mandibular canal, the inferior alveolar nerve splits near the medial pterygoid muscle, to the mucous membrane the roots of the premolars to become the mental nerve just lingual to the last molar. The mental nerve branch of the inferior alveo- soft tissue (mucosa) on the floor of the mouth and lar nerve exits from the body of the mandible through inner surface of the mandible and the lingual gingiva of the mental foramen (Fig. Finally, the inferior alveolar nerve comes off the man- Note that if an anesthetic solution is deposited next dibular nerve on the medial side of the lateral ptery- to the opening of the mandibular foramen, it could goid muscle (Figs. This large nerve block the passage of sensory nerve signals from all roughly parallels the direction of the lingual nerve to mandibular teeth on that side (by blocking the inferior descend between the sphenomandibular ligament and alveolar and its terminal incisive branch) and also the ramus to the mandibular foramen, where it gives off the skin of the chin and lip area (because another termi- mylohyoid nerve and then enters the mandible through nal branch, the mental nerve, has also been blocked). The mylohyoid ity to the mandibular foramen, its fibers may also be nerve (efferent) pierces the sphenomandibular liga- blocked, causing that side of the floor of the mouth, ment and travels forward in the mylohyoid groove to lingual gingiva, and anterior two thirds of the tongue to supply the mylohyoid muscle. The only part of the mandible that would Once the inferior alveolar nerve enters the mandible not be numb would be the tissue buccal to the molars, through the mandibular foramen, it is in the mandibu- which requires some additional anesthetic solution in lar canal within the body of the mandible, where it gives the cheek to block the buccal nerve. Trigeminal nerve distribution of the branches of the maxillary and mandibular divisions: The ophthalmic branches are shaded green, the maxillary nerve and branches are shaded red; the mandibular nerve and branches are blue. Other muscles supplied by the facial nerve to help summarize the distribution of the mandibular include the posterior belly of the digastric muscle and and maxillary sensory nerve branches to all teeth and stylohyoid muscle (Fig. They course portion of the temporal bone through the internal through the tympanic cavity eventually exiting of the acoustic meatus (Fig. It passes through join with the lingual nerve (branch of the mandibular the parotid gland. Nerves listed in those areas and anterior 2/3 of tongue innervate the mucosa medial to the (sensory) teeth. These are the nerves any dental student, dental hygiene student, or graduate of either profession should be most familiar with. Arrows indicate the location of the facial nerve that passes through the internal acoustic foramen (blue), the glossopharyngeal nerve that passes through the jugular foramen (green), and the hypoglossal nerve branches that pass through the hypoglossal canals (red) (not visible but on the lateral walls of the foramen magnum). Chapter 14 | Structures that Form the Foundation for Tooth Function 427 Petrotympanic fissure (facial n. One part of the facial nerve exits through the stylomastoid foramen (blue) and another small branch exits through the petrotympanic fissure (blue) where it joins up with the lingual branch of the trigeminal nerve to provide the anterior two thirds of the tongue with feeling (trigeminal nerve neurons) and taste (facial nerve neurons). Also, note the carotid canal where the internal carotid artery enters the braincase. It then passes down and for- citing a unique taste associated with monosodium glu- ward to enter the tongue. Additional taste buds can be found in other struc- area of the tongue is dependent upon the intensity of tures in the back of the mouth, such as the pillars of the fauces, hard and soft palate, epiglottis, and pharynx. Name the location where branches split sensation of touch and pain to the anterior two thirds off of the main nerves, and name the foramina (body) of the tongue. Anesthetizing nerve fibers of what nerve results in muscle fibers to contract, thus squeezing the numbness in half of the anterior two thirds of the teeth together? Which of the following nerve branches does not pain sensation to the mandibular teeth exits the need to be anesthetized in order to block the skull through what foramen? Which two nerves branch off the infraorbital nerve while it is in the infraorbital canal? Blood courses from the left ventricle nerves of the same name begin to parallel one another of the heart through the aorta to the common carotid somewhere in the neck or on the face. The external carotid artery gives jaw run a more wiggly or corkscrew course than do off the maxillary branches supplying structures in the veins. Superior vena cava Capillaries of Capillaries of mandibular pulp maxillary pulp Brachiocephalic v. Pathway of blood from the heart to the teeth *Think in terms of a drop of blood making this round trip. First, the lingual artery carotid artery enters the skull through the carotid canal (not seen on Fig. Like the lingual nerve, this of the external carotid just in front of the sternocleido- artery supplies the floor of the mouth, adjacent gingiva, mastoid muscle as required during cardiopulmonary and the sublingual gland. One example is where the right a shallow notch on the inferior border of the mandible and left superior and inferior labial arteries join at the just anterior to the insertion of the masseter muscle. As one might guess, such an anastomosis can This notch is called the antegonial notch (recall Fig. This is an important landmark to be aware of The third branch of the external carotid artery is the so that you will be able to stop the flow of blood to the maxillary artery, which is probably the most impor- lower part of the face in an emergency. It arises facial artery in the antegonial notch with your finger or from the external carotid within the parotid gland (Fig. The branches goes upward over the outer surface of the mandible to of the mandibular and pterygopalatine part (or first and the face. The ascending palatine artery comes branches of the pterygoid part (or middle part) provide off at the highest point of the first bend of the facial blood to the four pairs of muscles of mastication. Study artery before it passes onto the face, and it ascends to Figure 14-49 as you read about the following branches supply structures adjacent to the pharynx (including of each part of the maxillary artery. Also, notice the sim- the soft palate, the pharyngeal muscles, the mucosa of ilarity between the names of the vessels and the names the pharynx, and the palatine tonsil). After passing onto the face, the inferior and part of the maxillary artery supply the mandibu- superior labial arteries (Fig. Lateral correctly: branches of the maxillary artery supply nasal and angular arteries are the terminal branches of the mandible. It then conventional system whereby an artery terminates with divides into two branches: the mental artery, which many small capillaries. Maxillary artery and the branches of its three major parts: The branches of the mandibular part supply blood to the mandible and teeth, the pterygoid part supplies the muscles of mastication, and the pterygopalatine part supplies the maxillae and teeth. In many with the teeth but supply blood to the muscles of instances, they travel almost the same course as mastication (posterior and anterior deep temporalis, arteries. Veins that drain blood from • Pterygopalatine Part of the Maxillary Artery: Arteries the face on its way back to the heart are shown in to the Maxillae Figure 14-50. Branches that come off of the pterygopalatine (or Numerous veins drain blood from the maxillary and third) part of the maxillary artery supply the maxil- mandibular teeth and adjacent tissues into a pterygoid lary teeth and their periodontal ligaments. Each descending palatine of the lips and muscles around the mouth, the poste- branch of the maxillary artery supplies part of the rior part of the nasal cavity, the palate, the maxillary nasal cavity before it emerges onto the palate through alveolar process, and maxillary teeth. Its terminal part ascends that is, from the area of the oral cavity supplied by the through the incisive canal into the nasal cavity. Venous drainage of the face: The dotted lines represent deeper (less superficial) vessels. Notice how many veins come together in the pterygoid plexus of veins, an area prone to bleeding if the anesthetic syringe cuts any vessel wall within this plexus. During muscle contractions, however, blood complex when you consider that there is a deep facial is driven from the veins. The retromandibular passes into the brachiocephalic vein, to the superior vein drains into the facial vein where it becomes the vena cava, then through the heart and lungs to become short common facial vein that then empties into the oxygenated before being pumped back to the mouth internal jugular vein. An important superficial vein that also drains blood from the face is the facial vein, which roughly follows the course of the facial artery but, of course, carries blood in the opposite direction. Name It can also receive blood from the muscles of mastica- each vessel along the way. Just like the retromandibular vein, the facial vein interesting round trip, which takes place about empties through the common facial vein into the inter- every 10 to 15 seconds. Blood from the tongue drains through artery and its branches are probably the most lingual veins (not visible on Fig. Refer to Figure 14-51 capillary bed and then return this fluid to the vascu- while reading. In the arterial side of a capillary bed, blood Infection in the area of the chin and adjacent struc- pressure exceeds osmotic pressure, so fluid escapes tures including the tip of the tongue and tissues sur- into the tissue spaces. On the venous side of each capil- rounding the mandibular incisors—anterior floor of the lary bed, the blood pressure is lower, and the osmotic mouth, lower lip, and adjacent gingiva (gum tissue)— pressure becomes higher, forcing 90% of the tissue 33 all drain into the submental nodes just lingual to the fluid back into the venous capillary bed. When enlarged, these bulk of the remaining 10% of the fluid is the lymph, nodes can be palpated just posterior to the symphysis which passes into the lumen of lymph capillaries and is area of the mandible. Lymph nodes of the head and neck: These areas should be palpated during a head and neck Inferior deep cervical examination.