Adaptive radiotherapy in locally advanced esophageal cancer with atelectasis: a case report.

BACKGROUND: To the best of our knowledge, no study has reported mediastinal shift accompanied with obstructive atelectasis due to bulky primary esophageal tumor components treated with adaptive radiotherapy and concurrent chemotherapy. CASE PRESENTATION: Here we report the case of a 65-year-old male patient diagnosed with locally advanced thoracic esophageal squamous cell cancer, clinical T4bN1M0, stage IVA. Bronchoscopy and computed tomography (CT) revealed an almost complete obstruction of the lumen of the left bronchus due to compression by bulky primary esophageal tumor components. On admission, the patient presented with dyspnea and decreased arterial oxygen saturation. Chest radiography and CT on admission revealed mediastinal shift with left atelectasis, as opposed to findings from the chest radiography performed 26 days before admission. Because of the patient's overall good condition, we recommended definitive chemoradiotherapy instead of palliative bronchial stent placement. After obtaining the patient's consent, chemoradiotherapy was initiated on the following day and it comprised three-dimensional conformal radiotherapy with 60 Gy in 30 fractions with concurrent administration of cisplatin and 5-fluorouracil. During chemoradiotherapy, tumor location was monitored with cone-beam CT and chest radiography. Chemoradiotherapy on day 8 revealed no evidence of the mediastinal shift. CT simulation was reperformed to adjust the radiotherapy fields to account for geometrical changes induced by the absence of the mediastinal shift. Subsequently, the mediastinal shift and bronchial obstruction did not recur during the course of chemoradiotherapy. The patient completed the planned radiotherapy with concurrent and adjuvant chemotherapy, and no non-hematological grade ≥ 3 adverse events were observed. Complete response was confirmed 7 months after initiating chemoradiotherapy. Currently, no disease recurrence, dysphagia, or respiratory symptoms have been reported at 13 months after initiating chemoradiotherapy. CONCLUSIONS: In this study, a bulky primary esophageal tumor caused mediastinal shift due to ipsilateral bronchial obstruction. The close follow-up for monitoring resolution of the mediastinal shift during the course of chemoradiotherapy enabled adequate dose delivery to targets, thus reflecting the geometrical changes induced by the absence of the mediastinal shift. Adaptive radiotherapy technique was crucial for favorable patient outcomes in this challenging clinical situation.

Hyperbaric oxygen therapy in a case of cervical abscess extending to anterior mediastinum, with isolation of Prevotella corporis.

We present a case of an odontogenic abscess, first spreading at the lateral cervical level and then in mediastinum. We isolated an anaerobic bacterium, Prevotella corporis, rarely documented in literature. The mortality rates of cervical abscesses secondary to odontogenic infections and complicated by mediastinitis vary from 10% to 40%. Treatment of descending mediastinitis involves multidisciplinary teams such as otorhinolaryngology, thoracic surgeons, infectious disease physicians, anesthetists and intensivists. Due to the combined treatment with surgical drainage within 48 hours of hospitalisation, antibiotics and subsequent hyperbaric oxygen therapy, we have achieved complete recovery of the patient.

A case report of mediastinal ectopic parathyroid adenoma presented as parathyroid crisis localized by SPECT/CT.

INTRODUCTION: Parathyroid crisis due to ectopic parathyroid adenomas can pose diagnostic and management challenges, since it is quite rare in clinical practice. CLINICAL FINDINGS/PATIENT CONCERNS: A 67-year-old Chinese male presented as a parathyroid crisis due to an ectopic mediastinal parathyroid adenoma with his serum calcium and PTH markedly increased in short time. An ultrasonography and computed tomography (CT) scan of the neck did not reveal any parathyroid adenoma. Thoracic CT detected a contrast-enhanced mass in the mediastinum. Although the ectopic location is difficult to appreciate on anterior planar technetium-99m-sestamibi scintigraphy views but has been accurately localized with single photon-emission computed tomography/computed tomography. After fluid resuscitation, loop diuretic, and calcitonin treatment, a thoracoscope surgery was performed. The histopathology of the mediastinal nodule was consistent with a parathyroid adenoma. Hypocalcemia due to hungry bone syndrome occurred after surgery and was resolved quickly with large-dose calcium and calcitriol supplementation. He is asymptomatic and has normal serum calcium and PTH levels on regular follow-up. DIAGNOSES: The ultrasonography, CT, sestamibi, and single photon-emission computed tomography/computed tomography provide limited sensitivity in the detecting ectopic parathyroid adenomas alone. The combination of these techniques has incremental value in localizing ectopic parathyroid adenomas over either technique alone. CONCLUSION: Any parathyroid crisis without parathyroid adenoma in the neck should alert physicians to search for ectopic locations through combination of imaging techniques.

A Case of Ruptured Aneurysm of the Proper Esophageal Artery with Symptomatic Mediastinal Hematoma.

Mediastinal aneurysms are rare but potentially life-threatening. Among these, bronchial artery aneurysms are most frequently reported, whereas up to now aneurysms of the proper esophageal artery had never been reported. A 69-year-old woman was referred to our hospital for treatment of a massive mediastinal hematoma. Enhanced computed tomography and selective proper esophageal arteriography revealed a 5-mm aneurysm in the proper esophageal artery that arises from the thoracic aorta at the Th8 level and has an anastomotic branch with the bronchial artery peripherally. Transcatheter arterial embolization was successfully performed using a mixture of N-butyl cyanoacrylate and lipiodol (1:3 ratio, 0.3 ml). Post-embolization angiography showed no filling into the aneurysm. The patient recovered with no complications and was discharged on the 25th post-procedure day.

Usefulness of severe cardiac sympathetic dysfunction to predict the occurrence of rapid atrial fibrillation in patients with Wolff-Parkinson-White syndrome.

Atrial fibrillation (AF) can be a potentially life-threatening arrhythmia when it conducts rapidly through the accessory pathway, which was not predicted by the noninvasive method. We evaluated the cardiac sympathetic activity for predicting the occurrence of AF in patients with Wolff-Parkinson-White (WPW) syndrome. Iodine-123 metaiodobenzylguanidine scintigraphy was performed under stable sinus rhythm conditions at rest <1 week before an electrophysiologic study (EPS) to assess the sympathetic activity using the heart/mediastinum (H/M) ratio in 45 consecutive patients with WPW who had a history of supraventricular tachycardia (mean ± SD, age: 47 ± 17 years, 42.2% women). The study also included 15 normal healthy volunteers (56 ± 17 years, 40% women). The H/M ratio was lower in patients with WPW syndrome than in the normal control group, and in the 15 patients with AF induced during EPS than in the 30 patients without AF (p <0.0001). The sensitivity of H/M ratio ≤2.8 for predicting the AF induced during EPS was 75% in 12 of 16 patients, and the specificity was 89.7% in 26 of 29 patients. The H/M ratio was positively correlated with anterograde effective refractory period (r = 0.514, p <0.0001). The sensitivity of H/M ratio ≤2.75 for predicting the AF with a short anterograde effective refractory period (≤250 ms) was 91.7% in 11 of 12 patients, and the specificity was 90.9% in 30 of 33 patients. In conclusion, the severe cardiac sympathetic dysfunction was associated with the occurrence of AF, particularly in those with rapid AF and in patients with WPW syndrome.

The anterior mediastinum: anatomy and imaging procedures.

The mediastinum is divided into compartments (anterior, middle, posterior) on the basis of lateral chest radiographs. Several anatomical and radiological classifications of the mediastinum are reported in the literature. Most mediastinal abnormalities are initially suspected following chest radiography; the need for further investigation and the most appropriate imaging modality are largely dictated by the tentative diagnosis made on this examination. Although routine chest radiography initiates the evaluation of mediastinal disorders, it is rarely diagnostic: notable exceptions are teeth or bones within a mass, which are diagnostic of a teratoma; air/fluid levels suggest an oesophageal origin, hernia, cyst, or abscess. Chest radiography is followed by spiral computed tomography (sCT). However, even sCT with contrast material is occasionally diagnostic (a confident diagnosis can be made of some lesions such as mature teratoma and mediastinal goiter) but is usually sufficient for preoperative evaluation before mediastinotomy or mediastinoscopy: it is instrumental in planning further diagnostic workup. In certain cases, magnetic resonance imaging (MRI) may be complementary to sCT, but its use is not considered routine. Besides, although the anterior mediastinum is suitable for sonographic examination, the diagnostic value of ultrasonography has not been fully exploited. Thyroid scanning with radioactive iodine is useful in identifying and evaluating masses of suspected thyroid origin. The role of fluorodeoxyglucose positron emission tomography (FDG-PET) in mediastinal diseases continues to be evaluated: it has potential for differentiating between benign and malignant disease and is expected to play a more extensive role in the imaging of mediastinal neoplasms in the future. In this paper, the radiological features of masses located in the anterior mediastinum are discussed, with particular reference to radiographic and CT patterns useful to the clinician's everyday practice.

Mediastinal images resembling thymus following 131-I treatment for thyroid cancer.

The follow-up of Differentiated Thyroid Cancer conventionally includes serum thyroglobulin and periodic Whole Body Scans. The uptake of 131-I in normal and pathological tissues different from metastatic thyroid cancer sites is a cause of false-positive scans. Among them, mediastinal uptake caused by thymic hyperplasia can be observed. The aim of the present study was to review a series of 573 patients with differentiated thyroid cancer treated with 131-I after surgery between 1992 and 2003 looking above all for those with mediastinal images resembling thymus. This evaluation is presented together with some hypotheses on the relationships between thymus and thyroid. Moreover, some considerations are made on the differential diagnosis between thymus and mediastinal tumour thyroid residues.

Impaired Tc-99m MIBI uptake in the thyroid and parathyroid glands during early phase imaging in hemodialysis patients.

The purpose of this study is to evaluate the possible reasons of an observation of diminished uptake of Tc-99m MIBI in the early phase of parathyroid scintigraphy in the thyroid and parathyroid glands in patients with chronic renal failure who are being evaluated for hyperparathyroidism. Fourteen patients with secondary hyperparathyroidism all on hemodialysis with supplement therapy consisting of mainly vitamin D and calcium carbonate were studied. Neck and mediastinum images obtained at early and late phases were evaluated both visually and semiquantitatively. Patients with high PTH levels on hemodialysis showed diminished accumulation of radioactivity in the thyroid glands in the early phase compared to the soft tissue with a ratio of 1.54 +/- 0.39 (mean +/- std). A control group consisting of 10 patients with osteoporosis and Rickets' disease on vitamin D therapy was taken as control group A, as well as 11 patients with no problems other than cardiac who were not on any medication as control group B and 8 patients on hemodialysis only with normal PTH levels as control group C. Patients in control group A and C showed diminished accumulation of radioactivity in the thyroid glands in the early phase compared to the soft tissue with a ratio of 1.57 +/- 0.43 and 1.34 +/- 0.13, respectively, while patients in control group B showed good uptake 3.18 +/- 0.43. None of the studies showed parathyroid pathology. The results of this study show that patients with chronic renal failure under hemodialysis treatment are prone to show decreased uptake of the radioactivity. Another finding is that vitamin D supplements can cause diminished uptake of Tc-99m MIBI. A possible explanation is mentioned in the literature by an increase in PGP level and multi-drug resistance, so we suggest that it may play a role in impaired Tc-99m MIBI uptake in the thyroid phase and recommend cessation of vitamin D3 metabolites before performing parathyroid scintigraphy.

Potential pitfall in parathyroid sestamibi imaging resulting from a cardiac pacemaker.

A 47-year-old woman with a history of end-stage renal disease and hyperparathyroidism after total parathyroidectomy had Tc-99m sestamibi imaging to identify possible ectopic parathyroid tissue. This study was prompted by increasing calcium and parathyroid hormone levels after several years of taking calcium supplements necessitated by a surgically induced hypoparathyroid state and end-stage renal disease. The scan showed persistent linear activity in the upper right mediastinum in delayed images, after washout of the thyroid had occurred. Because of the unusual configuration of this finding, investigation of the patient's clinical history and other imaging studies was undertaken. The authors concluded that the unusual mediastinal uptake was not hyperactive parathyroid tissue, but rather was attributed to the presence of central venous pacemaker wires. Thus, this case illustrates a potential pitfall in parathyroid sestamibi imaging, the uptake of which may increase in the presence of a cardiac pacemaker, and it emphasizes the importance of correlative imaging.

Comparison of effects of enalapril and nitrendipine on cardiac sympathetic nervous system in essential hypertension.

OBJECTIVES: The purpose of this study was to assess the effects of enalapril and nitrendipine on the cardiac sympathetic nervous system. BACKGROUND: Angiotensin-converting enzyme inhibitors and long-acting calcium channel blockers have been widely used in the treatment of cardiovascular diseases, in some of which sympathetic overactivity plays a major role in the pathophysiology and prognosis. However, little information is available on the effects of these drugs on the cardiac sympathetic nervous system. METHODS: 123I-metaiodobenzylguanidine (MIBG) cardiac imaging was performed before and 3 months after drug administration in 46 patients with mild essential hypertension. Twenty-two patients were treated with 5 to 10 mg of enalapril once a day, and the other 24 with 5 to 10 mg of nitrendipine once a day. For comparison, 20 normotensive subjects were also studied. RESULTS: There were no significant differences between the basal characteristics in the 2 hypertensive groups. In both hypertensive groups, both systolic and diastolic blood pressures were significantly reduced to similar levels after the 3-month drug treatment. Before the drug treatment, the 2 hypertensive groups had a significantly higher washout rate and lower MIBG uptake than the normotensive subjects. The heart-to-mediastinum ratio significantly increased (p < 0.0001), with decreased (p < 0.002) washout rate after drug treatment in the enalapril group, but with no significant changes in the nitrendipine group. CONCLUSION: Enalapril could suppress cardiac sympathetic activity and nitrendipine had no effect on it. The knowledge of antihypertensive drugs on the cardiac sympathetic nervous system appears to be helpful in selecting appropriate treatment in cardiovascular diseases.

Digital radiography: comparison of different methods for imaging of the thorax and the gastrointestinal tracts.

In evaluating the image quality of the chest, four different analog and digital methods were compared. For peripheral lung field, the advanced multiple beam equalization radiography (AMBER) system was given the best score, followed in order by the storage-phosphor, conventional, and asymmetric film/screen systems. For the mediastinal field, the highest image quality was given to the AMBER system, followed by storage phosphor and asymmetric film/screen system. The best overall image quality, especially with regard to demonstration of pathologic alteration, was given to the AMBER system, followed by the storage-phosphor, conventional, and asymmetric film/screen radiography systems. In conclusion, AMBER demonstrated the highest image quality. The storage-phosphor system provided better results in the peripheral and mediastinal fields in comparison with conventional film/screen systems. Other digital systems including selenium chest radiography system and image intensifier digital radiography were also discussed.

CT evaluation of enhancing mediastinal masses.

The CT scans of 132 patients with mediastinal masses and CT scans from our teaching file were retrospectively reviewed to evaluate the role of contrast enhancement in limiting the differential diagnosis of a mediastinal mass. Ten patients with an enhancing mediastinal mass were found. Coupled with mass enhancement, location and hypertension were helpful in limiting the differential diagnosis. Four masses were of thyroid origin, and all were contiguous with neck thyroid. All patients with functioning paragangliomas were hypertensive and all intrapericardial enhancing masses were functioning paragangliomas. A normotensive patient had a nonfunctioning aortic body paraganglioma superiolateral to the aortic arch. An enhancing mass in a similar location in a hypertensive patient was a functioning paraganglioma. Castleman disease occurred posterior to the heart.

Direct cannulation and injection lymphangiography of the canine cardiac and pulmonary efferent mediastinal lymphatics in experimental congestive heart failure.

Lymphangiograms were made in dogs with experimental congestive heart failure by cannulation of the left cardiac efferent (LCE), left pulmonary efferent (LPE), or cardiopulmonary lymphatic and injection of radiopaque medium. The lymphoangiograms showed cardiac enlargement and dilated mediastinal lymphatic channels consistent with an increase in lymph flow. By consecutive injections in the LCE and LPE, wer demonstrated that a common channel, the cardiopulmonary lymphatic, is opacified by injection in either the LPE or LCE. This common channel has been called the "cardiac lymphatic" and used for the collection of "cardiac" lymph. The authors' experiments suggest that this cardiopulmonary lymphatic carries both cardiac and pulmonary lymph.

Experimental opacification of mediastinal lymph nodes by intraperitoneal injection of an iodinated fatty emulsion.

Absorption and lymphatic drainage of several lipiodol emulsions injected intraperitoneally have been studied in the rabbit and rat. Good opacification of the lymphatic channels and mediastinal lymph nodes is obtained in several hours with fine emulsions and in several days with coarse emulsions. The tolerance is related to dose, and the peritoneal reaction was moderate with the low doses, similar to that caused by the administration of physiologic saline alone. Computerized tomography in detecting low contrasts attained with small doses could render this method of indirect lymphography possible in man.

Application of direct cannulation and injection lymphangiography to the study of the canine cardiac and pulmonary efferent mediastinal lymphatics.

Lymphangiograms of canine cardiac and pulmonary efferent mediastinal lymphatics were made by cannulation and injection of Ethiodol. Injections were made singly and serially. The mediastinal lymphatics and lymph nodes, which constitute the pathways of drainage of the heart and lungs, were delineated from the point of cannulation to the right and left inferior cervical region where the right lymphatic duct and thoracic duct are located. Lymphangiography reveals that the lymphatics which drain the heart and lungs may join to form common mediastinal lymphatic channels. Interconnections between mediastinal channels were demonstrated. The lymphatics terminated in the region of both the right lymphatic duct and thoracic duct in every subject. The so-called "cardiac node of Drinker" is usually a group of pretracheal nodes rather than a single node. The pretracheal nodes and those more cephalad receive drainage of lymph from both the heart and lungs. These studies suggest that lymph collected by cannulation of a "cardiac" lymphatic adjacent to the "cardiac node" will contain pulmonary as well as cardiac lymph. Thus the high flows reported by many investigators for "cardiac" lymph probably indicates that pulmonary lymph is mixed with cardiac lymph, and that the experimental data should be interpreted with this in mind.

Hyperbaric oxygen in anaerobic infection of the medistinum.

In the last decade hyperbaric oxygen has been recognized as an important therapeutic tool in a variety of instances in which either destruction of anaerobic bacteria is urgent or an improvement in the oxygenation level is mandatory. We have used it successfully in a case of mediastinal anaerobic infection (gas gangrene) after medical and surgical measures had failed to eradicate the disease. The causative organism of gas gangrene, Clostridium perfringens (Welchii), is widely distributed. It may be cultured from the soil, house dust, human skin and faeces, etc. For this reason infection with Clostridium is practically inevitable whenever suitable conditions arise. As an anaerobic bacterium Clostridium Welchii multiplies readily in damaged tissues without contact with the air and devoid of a normal blood supply. This occurs especially in road accidents and war wounds in which broken bones and crushed muscles provide a suitable medium for the infection (Altmeier, 1965). Sometimes this infection can occur too after abdominal or gynaecological operations (Hitchcock, 1965). We present here a case of mediastinal gas gangrene which was caused by perforation of the oesophagus by a swallowed foreign body.