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Objective comparison of physical dysfunction after neck dissection.

Thirty-five patients who underwent a total of 44 neck dissections of various types were prospectively studied to compare differences in postoperative shoulder function. Those who underwent a radical neck dissection suffered the greatest reduction in shoulder movement and had severely abnormal electromyograms. Those who underwent modified neck dissection with preservation of the spinal accessory nerve suffered less loss of shoulder function than the radical neck dissection group, but not to a significant degree at 16 weeks; however, the electromyograms of patients who underwent modified neck dissection were significantly better than those of the radical neck dissection group, which suggests that these patients may improve with time. Indeed, a reevaluation of several patients at 1 year showed improvement in both shoulder function and electromyograms in those who underwent modified neck dissection. Patients who underwent supraomohyoid neck dissection that involved minimal dissection of the spinal accessory nerve had minimal loss of shoulder function and usually, normal electromyograms at 16 weeks that documented less injury to the spinal accessory nerve. Again, these patients had improvement with time. A correlational analysis revealed that the physical parameters correlated well with the electromyographic findings, whereas each patient's perception of disability did not. These findings suggest that, in patients in whom it is oncologically sound, a neck dissection that spares the spinal accessory nerve offers significant benefit in terms of shoulder function.

Accessory Nerve

Predictability of aortic dissection as a function of aortic diameter.

The role of aortic diameter on the occurrence of type A dissection was investigated in 73 patients with dilated ascending aorta at the time of pre-operative evaluation. Using transthoracic echocardiography for diagnosis and measurements, 54 patients were identified with type A dissection (group 1) and 19 without dissection (group 2). The true mean aortic diameters were identical (6.0 +/- 1.3 cm in group 1 and 6.4 +/- 1.4 cm in group 2; mean +/- SD; ns) as were the indexed aortic diameters (ratio of diameter/body surface area; 3.2 +/- 0.8 cm.m-2 and 3.4 +/- 0.7 cm.m-2, respectively; ns). However, the individual diameters showed a pronounced scatter in both groups (range from 3.6 +/- 11.0 cm). Of the 73 patients, 66 had surgery (47/54 with and 19/19 without dissection) and seven patients were treated medically. Emergency surgery was performed in 45/66 patients (all with acute type A dissection) and elective repair in 21/66 (19 without and two with chronic type A dissection). In-hospital mortality was 18% in the emergency group, 5% in the elective group and 57% in the medical group. It is concluded that patients with dilated ascending aorta have a substantial incidence of acute dissection. Their clinical course is unpredictable: acute dissection occurs in some, and in others the ascending aorta continues to enlarge without dissection. Because patients with dissection often arrive too late for elective repair and have to be operated on as emergencies with a higher operative risk, we recommend elective surgery before the diameter of the ascending aorta has reached 6 cm.

Aortic Dissection

Malaria sporozoite detection by dissection and ELISA to assess infectivity of afrotropical Anopheles (Diptera: Culicidae).

Malaria infection rates determined by dissection and Plasmodium falciparum enzyme-linked immunosorbent assay (ELISA) were compared for 26,935 Anopheles gambiae Giles sensu lato and 17,739 Anopheles funestus Giles collected during 20 mo in western Kenya. ELISA infection rates were about 43% higher than dissection sporozoite rates. In dissection-negative Anopheles, circumsporozoite (CS) protein was detected by ELISA in 5.2% of 10,017 salivary gland samples and in 12.2% of 237 thorax samples. The accuracy of dissection and ELISA techniques was compared by the following tests on a group of 352 field-collected Anopheles (held 10 d to ensure sporogonic development): salivary gland dissection, examination of Giemsa-stained dissection slides, ELISA tests on salivary gland and thorax body parts, and microscopic techniques for determining sporozoite loads. Respective infection rates were 9.9%, 10.8%, and 15.6% for dissection, stained slides, and ELISA. Sporozoite loads were associated significantly with ELISA absorbance values (r = 0.76). Compared with Giemsa-stained dissection slide results, the sensitivity of sporozoite detection was 92.1% for dissection compared with 78.9% for ELISA; specificity was 100.0% for dissection versus 92.0% for ELISA. Immunological detection of CS protein in head-thorax samples of Afrotropical vectors overestimated the proportion of infective Anopheles because the comparison of techniques indicated that 45.4% of the ELISA positive Anopheles did not contain salivary gland sporozoites.

Animals

Usefulness of transesophageal echocardiography in assessment of aortic dissection.

BACKGROUND: The value of transesophageal echocardiography in the assessment of patients with aortic dissection was studied. METHODS AND RESULTS: Group 1 (34 patients) represented all patients studied at our institution with this technique in whom aortic dissection was proven by aortography, surgery, or autopsy. Group 2 (27 patients) represented all patients studied with this technique at our institution in whom aortic dissection was excluded by aortography. Transesophageal echocardiography made a correct diagnosis of aortic dissection in 33 of 34 patients (sensitivity, 97%; specificity, 100%). It also correctly demonstrated the type of dissection in all 29 patients with aortographic or surgical proof. On the other hand, computed tomography scanning, performed in 24 of 34 patients in group 1, made a correct diagnosis in only 67% of patients and misclassified the type of dissection in 33%. Transesophageal echocardiography correctly identified involvement of the coronary arteries by aortic dissection in six of seven patients as well as absence of both left and right coronary artery involvement in 10 patients with aortic dissection. This technique was also useful in detecting communications between the true and false lumens, presence of thrombi in the false lumen, and, in two patients, localized dissection rupture with formation of a false aneurysm. In both groups 1 and 2, transesophageal echocardiography correctly identified patients with moderate to severe aortic regurgitation. CONCLUSIONS: Transesophageal echocardiography is very useful in the assessment of aortic dissection.

Aortic Dissection

[Meta-analysis of the prognosis of thoracic aortic dissection: changing mortality in the last four decades].

The acute dissection of the thoracic aorta is a potentially lethal event with a death rate of 1 to 2% per hour urging for undelayed diagnosis and adequate treatment. First, this paper highlights both the demographic characteristics and the classification according to anatomical and prognostic criteria, i.e. class I to III according to DeBakey and type A and B according to Daily (or Stanford). Moreover, the etiology of aortic dissection is explained, including factors such as degenerative changes of the aortic media layer, chronic trauma from hypertension, primary connective tissue disease and acute deceleration trauma. Second, the clinical criteria of acute (within 14 days of the index event) and chronic dissection (> 14 days) is discussed with respect to the current literature. The dominant part of this paper represents a meta-analytic approach comprising all available literature sources with respect to emerging changes in the prognosis of thoracic aortic dissection over 40 years as a function of either the type, the anatomic location, the acuity or the impact of medical or surgical treatment of this disorder. The meta-analysis revealed that in acute and chronic type A dissection medical treatment alone failed to lead to a significant improvement of 30 day-mortality rate (Tables 1 and 2, Figure 1). However, with surgical interventions the 30 day-mortality rate was continuously lowered from 60% to 10% within the past 30 years. A similar evolution was observed for the chronic type A dissection (Tables 3 and 4, Figure 2). Furthermore, the meta-analysis revealed that the acute type B dissection benefits from medical treatment, especially antihypertensive medication since the 30 day-mortality of 40% in 1960 decreased to less than 10% at present with monitoring and effective medication (Tables 1 and 2, Figure 3). In case of chronic type B dissection the literature survey revealed mortality numbers fluctuating between 2% and 20% without a clearcut beneficial effect of medical therapy throughout these years, though possibly revealing some advantage over surgical treatment. Thus, both for the acute and chronic type B dissection the antihypertensive therapy is considered treatment of first choice, whereas surgical interventions may be necessary for complicated and progressive cases. In summary, compared to the natural course of thoracic aortic dissection with only 10% survival-rate after one year of onset (Table 9, Figure 5), any effective mode of treatment may significantly lower the high spontaneous death rate.(ABSTRACT TRUNCATED AT 400 WORDS)

Aortic Dissection

A balloon-expandable intravascular stent for obliterating experimental aortic dissection.

Acute aortic dissection is a life-threatening condition. Aggressive hypotensive drug therapy is the initial treatment of choice, although emergent surgical intervention is often warranted. We evaluated the efficacy of a balloon-expandable intravascular stent for the internal obliteration of aortic dissection. It is a flexible, continuous, complex coil cut to the length needed at the time of insertion. It can be positioned in curved vessels, including the aortic arch. The stent was inserted in the thoracic and abdominal aorta of 12 dogs (group I). Six weeks after implantation the dogs underwent angiography and the stents were explanted for light and scanning electron microscopy. There were no instances of stent migration or change in configuration. The aortas did not rupture. All branch vessels remained patent. Light and scanning electron microscopy illustrated neointimal incorporation into the vascular wall except at orifices. Thoracic dissections were created surgically in an additional 24 mongrel dogs. Twelve dogs received stents immediately after creation of the dissection (group II). All 12 dissections were obliterated. Twelve dogs were allowed to recover after creation of the dissection to observe the natural history of that lesion (group III). Within 1 week, in group III, there were three deaths because of aortic rupture; eight dissections persisted, and one resealed spontaneously. Stents were placed in the eight persistent dissections. All eight dissections were obliterated. In both groups, after 6 weeks of stent placement, aortography was repeated, and stents were explanted for light and scanning electron microscopy. There were no instances of rupture. All branch vessels remained patent with no evidence of thrombosis. We conclude that because of its unique characteristics, the stent effectively obliterates the false lumen of experimental acute aortic dissections without occlusing side branches, damaging the aorta, or inducing thrombosis.

Aortic Dissection

Use of a morphologic classification to predict clinical outcome after dissection from coronary angioplasty.

To determine if morphology of procedure-associated dissections could help predict clinical outcome, angiograms of 691 coronary artery dissections resulting from percutaneous transluminal coronary angioplasty were categorized according to the National Heart, Lung, and Blood Institute classification system. Classes of dissection were then correlated with clinical outcome: 543 patients with type B dissections had no increase in morbidity and mortality when compared with patients without dissection, with a similar success rate of 93.7%. Complications in this group were low and compared favorably with complication rates in procedures not associated with dissection. One hundred forty-eight procedures associated with dissections of types C to F had a significant increase in in-hospital complications, including acute closure (31%), need for emergency coronary bypass surgery (37%), myocardial infarction (13%) and repeat angioplasty (24%). The overall clinical success rate for those with types C to F dissection was 38%. The differences in clinical success and acute complications between type B and types C to F dissections were statistically significant at p less than 0.0005 for all variables studied. The angiographic morphology of a dissection during coronary angioplasty can predict clinical outcome, aiding in selection of effective therapy.

Aged

Antegrade approach to radical retropubic prostatectomy in patients with difficult apical dissection.

Among 335 radical retropubic prostatectomies an antegrade dissection was used in 30 because of difficulty in developing the usual planes of dissection during apical dissection. The adequacy of tumor resection, preservation of sexual potency and urinary continence were compared in patients who underwent the antegrade dissection and those who underwent the standard retrograde nerve-sparing radical retropubic prostatectomy. Histopathological evaluation revealed no significant difference in the over-all completeness of tumor excision between the group having an antegrade dissection (16 of 30, 53% completely excised) and those having a retrograde dissection (177 of 305, 58% completely excised) (p = 0.62). Patients with clinically localized but pathological stage C disease undergoing an antegrade dissection and a nerve-sparing procedure had a significantly higher incidence of positive lateral margins (9 of 12, 75%) than the comparable group undergoing a retrograde dissection (40 of 99, 40%) (p = 0.02). The incidence of positive apical margins was similar in both groups, with 5 of 14 (36%) of the antegrade stage C cases (36%) having positive apical margins compared to 37 of 117 of the retrograde stage C cases (32%) (p = 0.65). Sexual potency was preserved in 5 of 6 patients (83%) treated with an antegrade dissection who had both neurovascular bundles preserved and were followed for at least 6 months, compared to 86 of 142 (61%) who underwent retrograde dissection (difference not significant, p = 0.26). Potency was preserved in 6 of 13 evaluable patients (46%) undergoing unilateral antegrade nerve-sparing procedure compared to 21 of 48 evaluable patients (44%) undergoing unilateral retrograde nerve-sparing procedure (p = 0.88). Of 22 patients followed for 1 year 21 (95%) have regained urinary continence. We conclude that the antegrade approach to radical retropubic prostatectomy provides results that are comparable to those achieved with the standard retrograde approach but that when an antegrade approach is chosen because of periprostatic fibrosis, bilateral preservation of the neurovascular bundles may result in a higher incidence of positive surgical margins.

Adenocarcinoma

Pathology of spontaneous dissection of intracranial arteries.

Spontaneous dissection of a major subarachnoid artery is an uncommon cause of stroke in young and apparently healthy individuals. Such dissection does not correlate well with systemic conditions such as emboli, thrombotic or hemorrhagic tendencies or hypertension, nor with disease of blood vessels such as atherosclerosis, fibromuscular dysplasia, cystic medial necrosis or Moya-Moya disease. Unusual exertion has been implicated as a factor in some cases. Gap defects were found in the internal elastic lamina near the site of dissection in three of four cases of spontaneous dissection reported here. It is suggested that such defects, because of their unusual size or number, may be responsible for initiating dissection in susceptible individuals. A detailed study of the major cerebral arteries in cases of dissection and control cases to document the size and frequency of such defects could shed light on the pathogenesis of spontaneous dissection. The subsequent course of events tends to differ in the internal carotid and vertebro-basilar systems. In most cases, the dissection in the internal carotid system is sub-intimal leading to thrombosis and cerebral infarction, while in the vertebrobasilar system dissection lies between the media and adventitia leading to subarachnoid hemorrhage. It is not known what structural differences of the two arterial systems may underlie this difference in the pattern of arterial dissection.

Adult

Aortic dissection: current expectations and treatment. Experience with 258 patients over 20 years.

Aortic dissection, the most common acute disease of the thoracic aorta, is associated with high mortality and morbidity. The authors reviewed their experience over the last 20 years with 258 patients who had aortic dissection (259 dissections). The diagnosis was made at autopsy in 69 (27%) patients (59 type A, 10 type B). Of the remainder, 97 patients had type A dissection (78 acute, 19 chronic) and 93 had type B dissection (56 acute, 37 chronic). The sudden onset of severe, unremitting chest pain associated with hyper- or hypotension or a history of hypertension are suggestive of acute aortic dissection. The diagnosis should be followed by prompt investigation and treatment. The 30-day survival rate for patients with type A dissection who underwent surgical treatment was 62%; survival rates for patients with type B dissection, acute and chronic, were 70% and 86% respectively with pharmacotherapy and 66% and 91% with surgery. The authors stress the importance of early, accurate diagnosis and immediate surgical treatment for all patients who have type A dissection and complicated or unresponsive (carefully monitored pharmacologic control of blood pressure) type B dissection.

Adult

Discontinuous vs in-continuity neck dissection in carcinoma of the oral cavity.

We compared the results of transoral excision of the primary tumor with discontinuous neck dissection with the results of in-continuity dissection of primary tumor and neck nodes in anteriorly localized squamous cell carcinoma of the oral cavity. We analyzed 27 patients who underwent 28 discontinuous dissections and 34 patients who underwent 40 in-continuity dissections for T2 anterior tongue or floor-of-mouth carcinoma. The overall ipsilateral neck recurrence rate was 11%. The discontinuous dissection group did significantly worse than the in-continuity dissection group, with a neck recurrence rate of 19%. Consequently, the actuarial 5-year survival of patients who underwent a discontinuous dissection was substantially decreased (63%) compared with patients who were treated by an in-continuity dissection (80%). Discontinuous neck dissection, thus, is not to be recommended in oral cancer.

Adult

Accuracy of M-mode and two-dimensional echocardiography in the diagnosis of aortic dissection: an experience with 128 cases.

The accuracy of combined M-mode and two-dimensional echocardiography in the diagnosis of aortic dissection was evaluated in 673 patients with a clinical suspicion of aortic dissection, over a six-year period. In 128 cases, the diagnosis of aortic dissection was confirmed by angiographic, tomographic (CT scan), or autopsy findings, or during surgery. Two echocardiographic features were found to support a diagnosis of aortic dissection: a dilation of at least one segment of the aorta (sensitivity 95%, specificity 51%) and a typical abnormal linear intraluminal echo corresponding to the intimal flap (sensitivity 67%, specificity 100%). This pathognomonic intimal flap was observed in 86 cases, of which three types could be distinguished: (1) a long oscillating flap (n = 15), (2) a long but minimally mobile linear echo which was duplicated and parallel to one or two aortic walls (n = 64), (3) a short, double linear image with a rapid systolic motion and high frequency oscillations. These features were found to have a high sensitivity in type I aortic dissection (88%), although in types II and III the sensitivity was much lower. In some cases, a fourth type of abnormal image could be detected: a small intraluminal echo moving in parallel to the aortic wall. This feature should be interpreted with caution since its predictive value for a positive examination was low (48%). Out of 23 cases in which the diagnosis of aortic dissection was suspected on the basis of this doubtful abnormal echo, it was confirmed in only 11 patients. The results in these 128 cases of aortic dissection indicate that two-dimensional echocardiography, which is easily performed at the patient's bedside, could take priority in investigations of this condition. It is extremely sensitive in the diagnosis of ascending aortic dissection, but much less so in the diagnosis of descending aortic dissection.

Aortic Dissection

Utility of two-dimensional echocardiography in suspected ascending aortic dissection.

The value of 2-dimensional echocardiography (2-D echo) in patients with suspected ascending aortic dissection was assessed. During a 5.5-year period, 56 consecutive patients underwent bedside 2-D echo for unexplained chest pain possibly due to ascending aortic dissection. Patients with obvious aortic dissection who proceeded directly to aortography were excluded and in all 56 study cases, 2-D echo was the initial diagnostic test. Using standard criteria, 2-D echo correctly identified all 13 patients with ascending aortic dissection. There were 5 false-positive study results and 38 true-negative results, yielding a sensitivity of 100%, specificity of 88% and overall diagnostic accuracy of 91%. In the group of 13 patients with confirmed ascending aortic dissection, 2-D echo identified 4 with pericardial fluid, and 3 of these patients (75%) died within 24 hours. In comparison, 7 patients in the group of 43 without confirmed dissection had pericardial fluid by 2-D echo and only 1 died (p less than 0.001). Finally, in the group of 38 patients with true-negative results, 2-D echo provided useful information in 16 (42%) that assisted or was essential in establishing an alternative diagnosis. However, 5 patients in this group had type III dissection and in none was it identified by 2-D echo. Thus, our data indicate that 2-D echo represents a reliable noninvasive method for rapidly diagnosing ascending aortic dissection at the bedside; offers important prognostic information which is directly related to the presence of pericardial fluid, and provides useful additional information which assists or establishes an alternative diagnosis when ascending aortic dissection is absent.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged

Spectrum of conditions initially suggesting acute aortic dissection but with negative aortograms.

Between 1963 and 1983, 55 patients presented to our hospital with a clinical picture that suggested aortic dissection but with aortograms that were interpreted as negative for that entity. In 4 patients, the aortographic findings subsequently proved to be false negative. The remaining 51 patients had the following diagnoses: myocardial infarction in 9 patients; aortic regurgitation in 5; thoracic nondissecting aneurysm in 4; musculoskeletal pain in 4; mediastinal tumor in 4; pericarditis in 3; acute coronary insufficiency in 3; cholecystitis in 2; miscellaneous in 3; and unknown in 14. The clinical features in these patients were compared with those of 125 patients with true aortic dissection. Three features were significantly more prevalent in patients with than without dissection: prior systemic hypertension, pain for 24 hours or less, and migratory pain. Patients without dissection were younger than those with distal dissection and had significantly less systemic hypertension, posterior thoracic pain and migratory pain. Patients without dissection had significantly less frequent congestive heart failure, pulse deficits and aortic regurgitation, and more frequent hypertension and pain for more than 24 hours than patients with proximal dissection. This study defines the actual differential diagnosis of aortic dissection at our hospital, the frequency of false-negative aortographic findings and contrasts the clinical features of patients with and without dissection.

Age Factors

Factors in the propagation of aortic dissections in canine thoracic aortas.

Factors were examined which altered the propagation of aortic dissections in canine aortas. Thoracic aortas were removed from sacrificed dogs from the distal end of the arch to the diaphragm. An intimal tear was created at the proximal end of the aorta. The dissection was propagated using a pulsatile pressure system with no flow. The aorta was perfused with a dilute black paint solution, which allowed both video monitoring of the extension of the dissection and measurement of the dissection rate. The dependence of the dissection rate on the variables peak pressure, (dP/dt)max and intimal tear depth was examined. The dissection rate was found to be dependent on (dP/dt)max (p less than 0.005) and the intimal tear depth, expressed as a percentage of wall thickness (p less than 0.01), but not on the peak pressure or intimal tear length. The equation relating the significant variables was log (dissection rate) = (-0.034) X % tear depth +(1.89 +/- 0.56) X (dP/dt)max -(4.3 +/- 1.8); r = 78. Thus a higher (dP/dt)max was associated with a more rapid dissection rate and a deeper intimal tear was associated with a slower dissection rate.

Aortic Dissection

Aortic dissection: magnetic resonance imaging.

Fifteen patients with suspected or known aortic dissection were imaged with magnetic resonance (MR). Thirteen of these patients were eventually shown to have dissection. In most instances the diagnosis was established by aortography and/or computed tomography (CT) prior to the MR study. Surgical proof (6/13) and/or aortographic proof (10/13) were available in 11/13 patients with aortic dissection. MR demonstrated the intimal flap and determined whether the dissection was type A or type B. In addition, MR: differentiated between the true and false lumens; determined the origins of the celiac, superior mesenteric, and renal arteries from the true or false lumen in the cases where the dissection extended into the abdominal aorta (8/12); allowed post-surgical surveillance of the dissection; and identified aortoannular ectasia in the three patients who had Marfan syndrome. In addition to the 13 cases with dissection, there were two cases in whom the diagnosis of dissection was excluded by MR. Our early experience suggests that MR can serve as the initial imaging test in clinically suspected cases of aortic dissection and that the information provided by MR is sufficient to manage many cases. Additionally, MR obviates the use of iodinated contrast media.

Adult

Neck dissection: radical or conservative.

Four hundred and forty-five neck dissections for epidermoid carcinoma over a 10-year period are reviewed as to local recurrence of neck disease. Three hundred and forty-seven dissections were radical en bloc procedures and in 98 a modified conservative technique was utilized. Cervical lymph node classification was applied and a comparison made of the two techniques. A review of the anatomy of cervical fascias and the technique of conservative neck dissection is given. Evaluation of this series of cases indicate that the control of local disease in the neck in the N0 and N1 groups is is accomplished as well with conservative dissection as with radical neck dissection. The number of conservative neck dissections for N2 disease was too limited for accurate comparison. There were no conservative neck dissections done for N3 disease. We suggest that conservative neck dissection be utilized for subclinical and N1 disease and that the classic en bloc dissection be reserved for N2 and N3 situations.

Carcinoma, Squamous Cell

The conservation neck dissection.

This study compares the neck tumor recurrence rate between patients treated with radical neck dissection and those treated with conservation neck dissection. A standard radical neck dissection modified by sparing at least the internal jugular vein or the spinal accessory nerve is defined as a conservation dissection. Six hundred ninety-one neck dissections performed on 631 patients in the Department of Otolaryngology-Head and Neck Surgery of the University of Illinois College of Medicine at Chicago were reviewed retrospectively. All patients had been followed postoperatively for at least 24 months. Group I consisted of 422 radical neck dissections. Group II contained 269 conservation neck dissections. We found no statistically significant difference in the rate of neck recurrence between the group of patients who underwent radical neck dissection and the group who underwent conservation neck dissection.

Adult