Volume 1, Issue 2 US $4.50 Editor: Panoramic radiology and the Allan G. Farman, BDS, PhD (odont.), DSc (odont.), detection of carotid atherosclerosis Diplomate of the American Board of Oral By Dr. Allan G. Farman inferior-posterior to the angle of and Maxillofacial the mandible.6Similar The most common manifestations Radiology, Professor of calcifications are found in the of atherosclerosis are coronary Radiology and Imaging coronary arteries of individuals Sciences, Department of artery disease, peripheral vascular having ischemic heart disease.10 Surgical and Hospital disease and cerebrovascular Atherosclerosis is not the only Dentistry, The University of accidents - stroke.1 In the USA, Louisville School of cause of soft-tissue calcifications 731,000 suffer a stroke each year Dentistry, Louisville, KY. seen anterior to the cervical with 165,000 not surviving.2 There vertebrae in panoramic are approximately 4 million stroke radiographs (Fig. 4). Care needs to Featured Article: survivors. Lifelong disabilities such be applied to differentiate as loss of mobility, aphasia, and carotid calcifications from Detecting Carotid depression often afflict survivors.3 Atherosclerosis calcified triticeous or thyroid Estimated healthcare costs cartilages, calcified lymph nodes related to acute and chronic and non-carotid phleboliths.8 For management of strokes are $40 In the Recent Literature: this reason, it is important to have billion annually. Atheroma-related an Anterior-Posterior (AP) formations of thrombi and emboli Mandibular Trauma radiograph of the neck made in the carotid artery is the most using soft tissue exposure settings. Age Determination frequent cause of stroke.4 Early Calcifications within the carotid detection of carotid Prevalence of Dental arteries will appear lateral to the atherosclerosis has the potential to Anomalies in Down spine, whereas calcifications in save lives and reduce medical Syndrome Patients the thyroid gland, thyroid expenditures. cartilage, triticeous cartilage or Locating Unerupted Teeth Since 1981, Friedlander and his epiglottis will be in the midline, colleagues have actively Stylohyoid Ligament superimposed over the spine. promoted panoramic radiology as Calcification Other calcifications that can be an aid in detecting patients at risk superimposed over the same part of stroke.5 Calcified of the panoramic film include atherosclerotic lesions at the F.A.Q.s phleboliths (sclerosing Film Reimbursement carotid bifurcation can be seen in hemangiomata), and calcified the lower corners of the panoramic acne or lymph nodes. The radiograph adjacent to the stylohyoid and stylomandibular cervical spine and hyoid bone (Fig. ligaments are situated posterior 1-3). Such atheroma may appear as rather than inferior to the a nodular radiopaque mass or as mandibular ramus – and therefore double radio-opaque vertical lines should be readily differentiated. within the neck. These calcifications are found at the level Associations of the lower margin of the third and Factors predisposing carotid Panoramic Corporation the entirety of the fourth cervical atherosclerosis include advancing [email protected] vertebra, about 1.5 to 2.5 cm age, male gender, systolic “Unfortunately, atherosclerosis is an insidious disease, often providing few signs and symptoms before life threatening catastrophic failure ensues in the form of a stroke or heart attack.” hypertension, hypercholester- Friedlander et al. (1999) studied olaemia, cigarette smoking, the prevalence of carotid atheroma diabetes mellitus, physical in male patients with obstructive inactivity, obesity, hemostatic sleep apnea.12 Detectable carotid factors, and coronary artery atheroma was found in 22 % of the disease. 1,3 Patients with diabetes study subjects compared to 4% in mellitus, those who have received age and gender matched controls. radiation therapy for head and neck cancer, and patients having Management obstructive sleep apnea have a While atherosclerosis-related greater prevalence of calcified maladies are perhaps the most carotid atheromas visible on prevalent cause of life-threatening panoramic radiographs than do human disease, there is still not a healthy, age-matched persons. thorough understanding of its Friedlander and Maeder (2000) causes. Associations are known, and examined the panoramic where these can be changed, the radiographs of men aged 55 to 81 progression of atheroma can be years who were receiving insulin to halted and even reversed. Such treat type 2 diabetes mellitus, and associations include hypertension, compared these to radiographs excessive dietary intake of from age-matched nondiabetic unsaturated fats, obesity, lack of controls.9 The incidence of physical activity, diabetes mellitus, detected carotid atheroma and tobacco habits. approximated 20% among the Unfortunately, atherosclerosis is diabetics compared to 4% for an insidious disease, often providing controls. few signs and symptoms before life Friedlander et al. (1998) studied threatening catastrophic failure the detection by panoramic ensues in the form of a stroke or radiography of radiation-induced heart attack. It is for this reason that accelerated atherosclerosis in the dentist’s careful evaluation of 10 patients with osteoradio-necrosis. the panoramic dental radiograph Fig. 1. Case #1: Carotid atherosclerosis The prevalence for carotid might be instrumental in saving a occur most frequently at the bifurcation calcifications in patients who had patient’s life. Individuals with of the common carotid. Initially there is received on averaged a dose of 60 panoramic radiographs intimal thickening. This is followed by varying degrees of obstruction. The Gy radiation therapy to the carotid demonstrating possible carotid atherosclerotic plaque often calcifies, artery disease should be followed bifurcation was 28%. The prevalence and it is the calcific deposits that can was 5% in a matched sample of up using an Anterior-Posterior (AP) be seen on panoramic radiography. non-irradiated patients. The head film with exposure settings difference was statistically highly sufficiently low to show the soft significant (p = 0.001). Chen et al. tissues (fig. 5). If calcification is (2001) found the prevalence of confirmed to be in the region of the calcified carotid atheroma in carotid arteries on the AP view, the panoramic radiographs for head patient should be referred to a and neck cancer patients prior to physician for confirmation of irradiation to be 7% giving further carotid atherosclerosis. Doppler support to irradiation promoting duplex sonogaphy is a noninvasive carotid artery atherosclerosis.11 method of choice for reevaluation “ It is for this reason that the dentist’s careful evaluation of the panoramic dental radiograph might be instrumental in saving a patient’s life.” of such individuals. images. Unless one can see the Patients with more than 60% anterior outline of the third and blockage of the carotid artery can fourth cervical vertebrae to the have the likelihood of stroke side of the panoramic image, one reduced by more than half if is probably missing details of the endarterectomy is performed to relevant region. Taking a radiograph surgically remove the plaque.13,14 with the patient one centimeter Those with less extensive lesions can anterior and one centimeter be treated using a drug regimen superior to the instructions of the such as aspirin (which is an manufacturer of the panoramic antiplatelet agent) or triflusal to system would optimize the image stem atherosclerosis progression for carotid calcification detection and reduce embolus formation.15,16 – as would underexposure; however, Modification in life-style is usually this is not recommended as it is necessary to increase daily suboptimal for evaluation of the exercise, avoid foods high in teeth and jaws. The panoramic Fig. 2. Case #2: Calcified atheroma of the carotid artery saturated fats and, where technique modification described bifurcation. There are extensions applicable, to be treated for would be best left to follow-up to a into both the internal and the hypertension and/or to cease regularly performed panoramic external carotid arteries in this smoking.2,17,18 radiograph. case. (Detail from panoramic (3) Viewing conditions are radiograph.) Cautions critical to detecting carotid (1) It is possible for a carotid artery atheroma using panoramic images. to be occluded by atheromatous The radiograph should be viewed plaque in the absence of on a view box with a variable noticeable calcification. While one rheostat to adjust the intensity of can question the possibility of the transmitted light. The ambient carotid disease when finding lighting should be subdued. A hot suspicious calcifications, one light is also helpful when looking for should never use the panoramic carotid calcifications. radiograph as a test for carotid atherosclerosis; you should not give the patient the “all clear” based References upon a panoramic radiograph 1. Tegos TJ, Kaldodiki E, Sabetai MM, Nicolaides AN. The genesis of alone. It is the patient’s physician, atherosclerosis and risk factors: a not his or her dentist that should be review. Angiology 2001;52:89-98. the final diagnostician. 2. Gorelick PB, Sacco RL, Smith DB, Fig. 3. Case #3: Calcified atheroma of (2) Different panoramic systems the carotid artery bifurcation. (Detail Alberts M, Mustone-Alexander L, from panoramic radiograph.) result in nonidentical radiographic Rader D, Ross JL, Raps E, Ozer MN, images. Some machines are likely to Brass LM, Malone