The role of MR imaging in detecting nodal disease in thyroidectomy patients with rising thyroglobulin levels.

BACKGROUND AND PURPOSE: One of the dilemmas facing clinicians treating patients with thyroid cancer is the evaluation of postthyroidectomy patients with rising serum thyroglobulin levels and indeterminate or normal findings on neck sonography. In this study, we examine the role of MR imaging in this subgroup of patients. MATERIALS AND METHODS: We retrospectively reviewed MR images of patients with thyroid cancer with abnormal lymph nodes in the retropharyngeal and parapharyngeal spaces and determined the size and signal-intensity characteristics of these nodes. We reviewed patient charts for the following history: 1) thyroidectomy, 2) rising thyroglobulin levels, 3) iodine-131 radiation therapy, 4) neck dissection, and 5) pathology on neck sonography and chest CT. We reviewed pathology findings to determine if thyroid cancer metastases were present in these lymph nodes. RESULTS: Eight patients had abnormal retropharyngeal space nodes, and 1 patient had a parapharyngeal space mass. Lymph nodes ranged from 7 to 25 mm. On MR imaging, 1 patient had a cystic node, 2 had complex nodes, and 6 had solid nodes. Eight patients had rising serum thyroglobulin levels and a history of thyroidectomy, radioiodine therapy, and neck dissection. Two of these patients had no pathologic nodes on sonography and normal findings on chest CT. Six patients had tissue sampling of their skull base node, and metastatic thyroid cancer was present in 5. CONCLUSIONS: MR imaging of the neck should be considered in thyroidectomy patients with rising serum thyroglobulin levels and a history of radioiodine therapy and neck dissection. Radiologists should carefully examine the retropharyngeal and parapharyngeal spaces in these patients because nodal metastases may occur there more commonly than realized.

Levosimendan in patients with acute myocardial ischaemia undergoing emergency surgical revascularization.

BACKGROUND AND OBJECTIVE: Levosimendan is a calcium-sensitizing drug that enhances myocardial contractility without increasing intracellular calcium. By activating adenosine triphosphate-dependent potassium channels it exerts cardioprotective and vasodilatory effects. METHODS: A retrospective matched pair analysis was performed in 52 patients undergoing emergency coronary artery bypass grafting for acute myocardial ischaemia with or without cardiogenic shock. A total of 27 patients received levosimendan (bolus 6 microg kg(-1); continuous infusion 0.2 microg kg(-1) min(-1)) in addition to catecholamines, while 25 patients were treated with catecholamines only. RESULTS: Predicted mortality by logistic EuroSCORE was 42% (14-90%) in the levosimendan group and 38% (9-90%) in the control group (median, range). Cardiogenic shock was diagnosed in 52% of the patients in both groups. Compared to the control group, levosimendan-treated patients had fewer intra-aortic balloon pumps inserted (33% vs. 76%, P 0.05) and need for dialysis (11% levosimendan; 32% control, P > 0.05) did not reach statistical significance. Length of hospital stay did not differ (14 +/- 18 days, levosimendan; 13 +/- 19 days, control; P > 0.05) between the two groups. CONCLUSION: In this retrospective matched pair analysis of 52 patients undergoing emergency coronary artery bypass grafting for acute ischaemia, levosimendan reduced morbidity. The reduced morbidity did not translate into reductions in mortality or length of stay. A larger, prospective randomized trial is warranted to confirm the potentially beneficial effects of levosimendan in patients with acute ischaemia.

Medical applications of electronic nose technology: review of current status.

Electronic noses, or artificial sensors of odorants. have been developed over the last ten years to perform a variety of identification tasks in various industries. This powerful technology is only beginning to be introduced in the field of medicine, but is promising in its potential to assist in diagnosis. This article reviews electronic nose technology and some initial investigations of potential applicability of the technology in the field of medicine.

[Is measuring the depth of anesthesia sensible? An overview on the currently available monitoring systems]. / Ist es sinnvoll, die Narkosetiefe zu messen? - Ein Versuch der Marktübersicht über die kommerziell erhältlichen Geräte zur Messung der Narkosetiefe.

Without any doubt there is an increasing need for accurately measuring depth of anesthesia - from the viewpoint of the anesthesiologist and also of the patient. The ideal monitoring should fulfill the following criteria: It should be applicable for any type of anesthesia (intravenous as well as inhalative anesthesia); the monitor must have an extremely high sensitivity (each patient being awake must be recognized by the device).If the monitor does not have a high sensitivity, the monitor itself might lead to an increasing number of patients being awake during anaesthesia, because the anesthesiologist might rely on the monitor and does not deepen anesthesia while the patient is awake. Specificity is not as important as sensitivity. As incidence of interoperative awareness is low, one must monitor more than 750 patients to recognize only one patient who is awake. Finally, the monitoring device must be economic. If costs are considerably increased by measuring depth of anesthesia in today's climate of cost consciousness, the monitoring has to be restricted to special high risk groups of patients. If monitoring depth of anesthesia will become simple, safe, and economic, each anesthesia should be monitored for its depth, as today each patient needs pulseoxymetry. We try to give an orientation about the available devices for monitoring depth of anesthesia. Since the introduction of BIS interest in measuring depth of anesthesia is growing very dynamically. Due to the dynamic growth we hope that we were able to present an actual and complete overview about the monitoring systems for measuring depth of anesthesia. Until today no monitoring system has proven to fulfill the mentioned criteria. Monitoring of the depth of anesthesia will be based on any processing of the spontaneous EEG or its evoked potentials. Which type of monitoring, entropy, BIS, PSI, or MLAEP will be used in clinical routine will be shown in the future. All available monitors are no predictors, whether depth of anesthesia is sufficient for the next painful surgical stimulus. They can only monitor the anesthetic state at the time of measurement. There is no "golden number" predicting absolutely safely that the patient is in adequate anesthesia. The anesthetist must consider any technique for monitoring of the depth of anesthesia as an additional help in improving care for his patient.

Feasibility and outcome of endoscopic staple-assisted esophagodiverticulostomy for Zenker's diverticulum.

OBJECTIVES/HYPOTHESIS: Endoscopic staple-assisted esophagodiverticulostomy (ESED) is a newly described method of surgically correcting Zenker's diverticulum. Initial reports on the ease and success of the surgery have been quite enthusiastic, making it seem the procedure of choice. We initiated the procedure in an algorithm of treatment of Zenker's diverticulum, to further explore the feasibility and outcome of this new technique. STUDY DESIGN: This is a case series of 23 patients with Zenker's diverticulum who have undergone surgical repair. For each patient, an attempt at ESED was made. If unsuccessful, an open approach was then taken. RESULTS: Seven of 23 patients (30%) were unable to be treated with ESED because of inability to expose the diverticulum or unfavorable anatomy of the diverticulum itself. Of the remaining 16 patients, ESED was successful in resolving the symptoms of diverticulum in 14 (87%). Two patients (13%) were somewhat improved but had persistent dysphagia. No significant complications occurred. All patients resumed oral diet within the first 24 hours after surgery. CONCLUSION: Esophagodiverticulostomy is an excellent method of surgically correcting Zenker's diverticulum in many patients, but anatomical considerations may prevent its use, making open approaches of continued importance in a surgeon's armamentarium.

Target-controlled infusion or manually controlled infusion of propofol in high-risk patients with severely reduced left ventricular function.

OBJECTIVE: To compare hemodynamics, time to extubation, and costs of target-controlled infusion (TCI) with manually controlled infusion (MCI) of propofol in high-risk cardiac surgery patients. DESIGN: Prospective, randomized. SETTING: Major community university-affiliated hospital. PARTICIPANTS: Twenty patients undergoing first-time implantation of a cardioverter-defibrillator with severely reduced left ventricular function (left ventricular ejection fraction <30%). INTERVENTIONS: Anesthesia was performed using remifentanil, 0.2 to 0.3 microg/kg/min, and propofol. Propofol was used as TCI (plasma target concentration, 2 to 3 microg x mL; n = 10) or MCI (2.5 to 3.5 mg/kg/hr; n = 10). MEASUREMENTS AND MAIN RESULTS: Hemodynamics were measured at 6 data points: T1, before anesthesia; T2, after intubation; T3, after skin incision; T4, after first defibrillation; T5, after third defibrillation; and T6, after extubation. There were no significant hemodynamic differences between the 2 groups. Dobutamine was required to maintain cardiac index >2 L/min/m(2) in significantly more patients of the TCI group than of the MCI group. Mean dose of propofol was higher in the TCI patients (6.0 +/- 1.0 mg/kg/hr) than in the MCI patients (3.0 +/- 0.4 mg/kg/hr) (p < 0.05), whereas doses of remifentanil did not differ. Time to extubation was significantly shorter in the MCI (11.9 +/- 2.4 min) versus the TCI group (15.6 +/- 6.8 min). Costs were significantly lower in MCI patients (34.73 dollars) than in TCI patients (44.76 dollars). CONCLUSIONS: In patients with severely reduced left ventricular function, TCI and MCI of propofol in combination with remifentanil showed similar hemodynamics. TCI patients needed inotropic support more often than MCI-treated patients. Although extubation time was longer in TCI patients and costs were higher, both anesthesia techniques can be recommended for early extubation after implantation of a cardioverter-defibrillator.

A comparison of monopolar electrosurgery to a new multipolar electrosurgical system in a rat model.

OBJECTIVES/HYPOTHESIS: The purpose of this study is to compare collateral tissue damage and wound healing in incisions created by electro-dissociation and conventional electrosurgery. Conventional electrosurgery has been used as an alternative to the scalpel to improve hemostasis. However, the heat generated by this instrument can cause tissue damage surrounding the incision, limiting its use around nerves and large blood vessels. A new technology, Coblation (Arthrocare Corp., Sunnyvale, CA), uses "electro-dissociation" to achieve similar results by creating charged particles from a conductive medium to make an incision while simultaneously achieving hemostasis. This new approach to electrosurgery may reduce soft tissue damage. METHODS: Two prospective, matched design experiments were performed. In experiment I, both devices were set at the same electrical power in watts and then used to create an incision on the tongue of rats. In experiment II, the electrical power settings of both devices were adjusted until they created incisions of the same size. Epithelial destruction and collateral tissue damage were measured in histologically prepared tissue in both experiments, and the wound healing process was observed in experiment II at 0, 3, 7, and 14 days after surgery. RESULTS: The results showed that the electro-dissociation method created significantly less epithelial destruction and collateral tissue damage in both experiments. Granulation tissue formation was also significantly less extensive in the electrodissociation-induced incision after 7 and 14 days of recovery. CONCLUSIONS: Wound healing may be faster than with conventional electrosurgery if the Coblation device is used.

Compression stockings prophylaxis of emergent varicose veins in pregnancy: a prospective randomised controlled study.

QUESTIONS UNDER STUDY: To determine the efficacy of compression stockings in preventing emergent varicose veins in pregnancy. METHODS: A prospective randomised controlled study in the outpatient department of the University Hospital of Zurich, Switzerland, including women with uncomplicated pregnancies <12 weeks at outset of study. A no-stockings control group (n = 15) was compared with two treatment groups: group 1 (n = 12) wore compression class I stockings (18-21 mm Hg) on the left leg and class II stockings (25-32 mm Hg) on the right; in group 2 (n = 15), the compression classes were reversed. Stockings were worn from study entry to term. Endpoints were emergence and worsening of superficial varicose veins, long saphenous vein reflux at the sapheno-femoral junction, and leg symptoms (pain, discomfort, cramps) during pregnancy. RESULTS: Both classes of compression stockings failed to prevent the emergence of superficial varicose veins. However, long saphenous vein reflux at the sapheno-femoral junction was observed in the third trimester in only 1/27 treated women vs. 4/15 controls (p = 0.047); in addition, more treated women reported improved leg symptoms (7/27 vs. 0/15 controls; p = 0.045). Emergent varicose changes, however, did not differ significantly (7/14 controls vs. 5/12 in group 1 and 8/14 in group 2; 3x3 table, Fisher's exact = 0.94). CONCLUSIONS: Although compression stockings do not prevent the emergence of gestational varicose veins, they significantly decrease the incidence of long saphenous vein reflux at the sapheno-femoral junction and improve leg symptoms. Our results also suggest that superficial varices and deep venous insufficiency may have a different aetiology.

Comparison of two different anesthesia regimens in patients undergoing aortocoronary bypass grafting surgery: sufentanil-midazolam versus remifentanil-propofol.

OBJECTIVE: To compare intraoperative hemodynamics and depth of anesthesia using sufentanil-midazolam (SM) versus remifentanil-propofol (RP) anesthesia. DESIGN: Prospective, randomized study. SETTING: Clinical investigation in an urban, university-affiliated hospital. PARTICIPANTS: Forty patients undergoing elective first-time coronary artery bypass graft surgery. INTERVENTIONS: Twenty patients were anesthetized using SM and 20 patients using RP. MEASUREMENTS AND MAIN RESULTS: Hemodynamic monitoring included a 5-lead electrocardiogram, a radial artery catheter, and a pulmonary artery catheter. Depth of anesthesia was assessed using bispectral index (BIS). Data were obtained after induction of anesthesia (T1), after sternotomy (T2), after pericardiotomy (T3), 5 minutes after cardiopulmonary bypass (CPB) (T4), after closure of thorax (T5), and at the end of surgery (T6). The 2 groups were comparable with regard to demographic and perioperative data. There were no significant differences of any hemodynamic parameter at any time between the 2 groups. In both groups, systemic vascular resistance increased at T2 and decreased at T4 from baseline value (p < 0.05). Cardiac index increased at T4 in both groups from baseline value (p < 0.05); 55% of the patients of both groups needed low-dose dobutamine after CPB. During CPB, 40% of the RP patients needed norepinephrine versus 35% of the SM patients. BIS was lower in the RP than in the SM group at T2 and T3 (p < 0.05). BIS values indicating intraoperative awareness were not noted. CONCLUSION: Both anesthesia regimens provided stable hemodynamics and adequate anesthesia in patients undergoing coronary artery bypass graft surgery.

Preoperative imaging to predict orbital invasion by tumor.

BACKGROUND: Our purpose was to examine the accuracy of preoperative imaging in assessing tumor invasion of the orbit and nasolacrimal system. METHODS: Nineteen preoperative CT and 17 preoperative MR images from patients at risk for orbital invasion were retrospectively reviewed. Invasion was corroborated by pathologic and intraoperative assessment. RESULTS: Tumor adjacent to the periorbita was the most sensitive predictor of orbital invasion (90%) for both CT and MRI. Extraocular muscle involvement on MRI (100%) and orbital fat obliteration (80% MRI, 86% CT) had the highest positive predictive values of the criteria evaluated. Extraocular muscle displacement and enhancement were less accurate (<65%) predictors. No one criterion was >79% accurate in predicting orbital invasion. Six or more positive criteria predicted invasion with 67% sensitivity and 80% specificity (accuracy, 72%). CT was more accurate than MRI in seven of nine criteria. Invasion of the nasolacrimal system was predicted accurately (89%). CONCLUSIONS: Although preoperative imaging can aid in surgical planning, it should not replace intraoperative assessment in ambiguous cases of orbital invasion.

Use of an electronic nose to distinguish cerebrospinal fluid from serum.

BACKGROUND: Efforts to mimic the biologic olfactory system have resulted in the development of an electronic nose, whereby volatile gases may be identified by means of organic semiconductors. Such devices have been used in the food and beverage industry for quality-control purposes, but to date have not been used in the field of medicine. OBJECTIVE: To present the application of an electronic nose for clinical decision making by assessing the ability of an electronic nose to distinguish cerebrospinal fluid (CSF) from serum. DESIGN: Randomized, prospective, masked study. SUBJECTS: Nineteen matched sets of CSF and serum from inpatients at a university hospital. RESULTS: The electronic nose was able to distinguish CSF from serum in 18 of 19 patients. The data points for 18 of 19 CSF and 18 of 19 serum samples were within statistically distinct cluster groups, suggesting that the device is able to identify an unknown sample as CSF or serum. CONCLUSIONS: This new technology is able to distinguish CSF from serum with a high degree of accuracy and speed, and with small sample quantity, potentially allowing the physician to identify reliably CSF otorrhea or rhinorrhea. This revolutionary diagnostic approach may have further, widespread application in the field of otorhinolaryngology and in medicine as a whole.

Clinical care pathways: decreasing resource utilization in head and neck surgical patients.

In this era of decreasing reimbursement, health systems have been forced to become more efficient and decrease resource utilization to remain financially viable. One of the methods of internal cost control has been the use of clinical pathways. Given the complexity of treatment of head and neck cancer patients, clinical pathways can help to standardize decision making and introduce uniformity in resource utilization. The objective of this study is to compare resource utilization and outcomes before and after implementation of a clinical pathway for head and neck surgical patients. We observed significant decreases in hospital costs as well as shorter lengths of stay after pathway implementation. It is our belief that a uniform management tool is beneficial in this complex disease.

Endoscopically assisted anterior cranial skull base resection of sinonasal tumors.

The traditional approach to sinonasal tumors involving the base of skull has been the anterior craniofacial resection. Endoscopic techniques have created the potential to approach the intranasal aspect of skull base lesions without external incisions and still develop an en bloc resection when removed. We report our initial experience with skull base neoplasms in which the otolaryngic portion of the standard resection was accomplished instead through an endoscopic approach. The nature of lesions favorable for this approach and associated technical issues are discussed. Although we do not consider this approach a replacement for the traditional anterior craniofacial resection, it is an important adjunct in the skull base surgeon's armamentarium.

Superficial siderosis of the CNS associated with multiple cavernous malformations.

Superficial siderosis of the CNS due to chronic, recurrent subarachnoid hemorrhage is an uncommon and potentially debilitating disorder. The classic clinical manifestation is progressive bilateral sensorineural hearing loss (SNHL), although ataxia and pyramidal signs also are observed frequently. Cavernous malformations rarely present with subarachnoid hemorrhage. We describe an unusual case of a young patient who presented with progressive, bilateral SNHL who was found to have superficial CNS siderosis associated with multiple cavernous malformations.

Dynamic cardiomyoplasty in patients with end-stage heart failure: anaesthetic considerations.

Dynamic cardiomyoplasty is used increasingly for patients with chronic heart failure, with approximately 500 cases having been performed. The latissimus dorsi muscle is prepared maintaining its vascular supply and the muscle flap is wrapped around the heart and connected to a cardiomyostimulator. The muscle is later stimulated synchronously with ventricular systole to augment the heart. Our experience of 22 patients with chronic heart failure (NYHA III-IV) undergoing dynamic cardiomyoplasty is described from the anaesthetist's point of view. Two patients are reported as case reports. The challenge is to manage patients with severely impaired left ventricular function, who do not obtain immediate benefit from the operation. Our experience supports the importance of early use of inotropic agents.

Total intravenous anesthesia with remifentanil and propofol for implantation of cardioverter-defibrillators in patients with severely reduced left ventricular function.

OBJECTIVE: To determine the cardiocirculatory effects of total intravenous anesthesia (TIVA) using remifentanil and propofol in high-risk cardiac surgical patients. DESIGN: Prospective study of 20 patients undergoing first-time implantation of a cardioverter-defibrillator (ICD). SETTING: Major, community, university-affiliated hospital. PARTICIPANTS AND INTERVENTIONS: In 20 patients with severely reduced left ventricular function (left ventricular ejection fraction <30%) undergoing first-time implantation of an ICD, TIVA using remifentanil and propofol was performed. MEASUREMENTS AND MAIN RESULTS: Extensive hemodynamic monitoring using a pulmonary artery catheter was performed: (T1) before induction of anesthesia, (T2) after intubation, (T3) after skin incision, (T4) after first defibrillation, and (T5) 10 minutes after extubation. Propofol, 3.0 +/- 0.6 mg/kg/h (range, 1.9 to 4.4 mg/kg/h), and remifentanil, 0.30 +/- 0.05 microg/kg/min (range, 0.21 to 0.40 microg/kg/min), were used. Total costs added up to US $44.60 per patient. Patients could be extubated within 12.5 +/- 4.2 minutes after stopping anesthesia. There were significant decreases in heart rate (HR; from 77 +/- 12 to 57 +/- 10 beats/min [T3]), mean arterial blood pressure (MAP; from 98 +/- 14 to 70 +/- 12 mmHg [T2]), and systemic vascular resistance (from 1,551 +/- 309 to 1,233 +/- 274 dyne x s x cm(-5) [T2]). Cardiac index (CI) slightly decreased only at T3 (from 2.46 +/- 0.42 to 1.92 +/- 0.29 L/min/m2; p = 0.04). The decrease in MAP could easily be treated by volume infusion in most patients (17 patients). Sixty-five percent of the patients needed dobutamine to increase CI to greater than 2.0 L/min/m2 (mean dose, 2.2 +/- 1.8 microg/kg/min). Dobutamine could be stopped before extubation in all patients. No patient needed sustained inotropic or ventilatory support and intensive care therapy could be avoided. CONCLUSION: TIVA using remifentanil and propofol in patients with severely reduced left ventricular function is safe, well-controllable, and allows early extubation after implantation of an ICD. Because patients without complications did not need a postoperative intensive care stay, costs may be considerably reduced.

Endoscopic management of sinonasal inverted papilloma.

Since 1992, 42 patients at the University of Pennsylvania have been treated for inverted papilloma (IP). Thirty-three patients were managed endoscopically with or without a Caldwell Luc approach (CLA) and retrospectively analyzed. The CLA, which involves a gingivobuccal incision for access to the maxillary sinus, is distinguished from a formal Caldwell Luc procedure. These 33 patients with histologically confirmed IP were without evidence of malignancy. They also did not have evidence of intracranial, orbital, or frontal sinus IP. Seventeen of 33 patients (17/33) were without prior treatment (primary). Sixteen of 33 (16/33) presented from an outside institution with recurrent IP (secondary). The recurrence rate using this method to treat primary IP was 6% (1/17), and for secondary IP was 25% (4/16). Scheduled postoperative endoscopic surveillance permitted early detection of recurrence and continued endoscopic control of IP. All 33 patients were endoscopically free of disease at the end of the study. These preliminary data are encouraging for the use of intranasal endoscopy with and without CLA as a means of managing and controlling IP in selected cases.

Pain management in cardiac surgery patients: comparison between standard therapy and patient-controlled analgesia regimen.

OBJECTIVE: To compare standard nurse-based pain therapy with a patient-controlled analgesia (PCA) regimen. DESIGN: Prospective, randomized study. SETTING: Single-institutional, clinical investigation in an urban, university-affiliated hospital. PARTICIPANTS: Sixty patients undergoing elective first-time cardiac surgery were included. INTERVENTIONS: In 30 patients, a standard analgesic regimen was used, and in 30 patients, a PCA regimen was used. The perioperative and postoperative management was similar for all patients. MEASUREMENTS AND MAIN RESULTS: Degree of sedation, satisfaction, and pain (by visual analog scale [VAS]) was assessed within the first 3 postoperative days. Vital capacity (VC) and forced expiratory volume in 1 second (FEV1) were measured using a portable spirometry system. Cortisol and troponin T (TnT) plasma levels were also measured. The expectation of pain was similar in both groups, and the postoperative pain score was significantly lower in the PCA than in the standard group throughout the study period. Significantly more piritramid was used in the PCA (total, 75.6 +/- 33.4 mg) than in the standard group (total, 20.1 +/- 31.9 mg). VC and FEV1 were significantly lower in the standard group compared with the PCA patients. Cortisol and TnT plasma levels were similar in both groups. Frequency of side effects were similar for both groups. CONCLUSION: Because of the beneficial effects with regard to degree of pain and satisfaction, pain management using PCA systems can be recommended for cardiac surgery patients. It appears to be superior to standard nurse-based pain therapy.

Neoplastic fixation to the prevertebral compartment by squamous cell carcinoma of the head and neck.

OBJECTIVE: The purpose of this study was to determine the accuracy of MR imaging in determining fixation of squamous cell carcinomas to the prevertebral space. MATERIALS AND METHODS: MR images of 15 patients with large pharyngeal carcinoma (n = 13) or laryngeal carcinomas with pharyngeal extension (n = 2) were retrospectively reviewed independently by two head and neck radiologists who were unaware of the surgical findings. MR images were evaluated for four criteria in the prevertebral longus muscle complex: muscle concavity, irregular tumor-muscle interface, T2 hyperintensity, and enhancement. All patients underwent panendoscopy where fixation or mobility of the tumor relative to the prevertebral fascia was assessed by manual manipulation. Tumors in six patients were fixed to the prevertebral space and inoperable. In nine patients whose tumors were not fixed, open neck explorations were performed and tumors were resected in seven patients. MR findings were compared with panendoscopy in all patients and with intraoperative assessment in nine patients. RESULTS: Eleven of 15 patients had at least two of the MR imaging criteria present. None of the MR findings were both sensitive and specific for tumor fixation. Although muscle concavity and enhancement each had a sensitivity of 88%, both criteria suffered from low specificity (14% and 29%, respectively). An irregular tumor-muscle interface and muscle T2 hyperintensity were criteria that suffered from both low sensitivity and specificity. Accuracy of the imaging criteria independently ranged from 53% to 60%. CONCLUSION: Although abnormal muscle contour, T2 hyperintensity, and enhancement are frequently present in neck carcinomas that are fixed to the prevertebral space, these findings may also be present in patients in whom the tumor is mobile and resectable. MR imaging may not be able to differentiate between neoplastic fixation and nonneoplastic changes in the prevertebral space.