Imaging the posterior mediastinum: a multimodality approach

Dysphagia With Unusual Etiology: A Case Report

Here, we present a case of dysphagia with a very unusual etiology. Dysphagia is a symptom of concern and can occur secondary to multiple etiologies. Therefore, prompt and appropriate evaluation is necessary, as treatment varies depending on the underlying cause. Our patient was a 73-year-old female admitted for dysphagia associated with recent significant weight loss and a history of long-term smoking. A CT scan of her neck revealed a mass that was compressing the esophagus, but the etiology of the mass was unexpected. This case highlights the importance of considering rare causes of dysphagia and underscores the need for physicians to be aware of them.

[Lesions of the paravertebral mediastinum]

BACKGROUND

Lesions of the paravertebral mediastinum are rare, and knowledge of possible differential diagnoses is essential for clinical practice.

OBJECTIVE/METHODS

To review common lesions of the paravertebral mediastinum.

RESULTS

The paravertebral mediastinum mainly includes fatty tissue and neurogenic structures. Imaging is commonly performed using computed tomography (CT) and magnetic resonance imaging (MRI). Neurogenic tumors are the most common lesions of the paravertebral mediastinum. Other pathologies include extramedullary hematopoiesis, lipomatous, lymphogenic, inflammatory, and cystic lesions. Moreover, also diaphragmatic hernias, vascular and esophageal pathologies may be found in the paravertebral mediastinum.

The surgical anatomy of a (robot-assisted) minimally invasive transcervical esophagectomy

BACKGROUND

Transcervical esophagectomy allows for esophagectomy through transcervical access and bypasses the thoracic cavity, thereby eliminating single lung ventilation. A challenging surgical approach demands thorough understanding of the encountered anatomy. This study aims to provide a comprehensive overview of surgical anatomy encountered during the (robot-assisted) minimally invasive transcervical esophagectomy (RACE and MICE).

METHODS

To assess the surgical anatomy of the lower neck and mediastinum, MR images were made of a body donor after, which it was sliced at 24-μm intervals with a cryomacrotome. Images were made every 3 slices resulting in 3.200 images of which a digital 3D multiplanar reconstruction was made. For macroscopic verification, microscopic slices were made and stained every 5 mm (Mallory-Cason). Schematic drawings were made of the 3D reconstruction to demonstrate the course of essential anatomical structures in the operation field and identify anatomical landmarks.

RESULTS

Surgical anatomy 'boxes' of three levels (superior thoracic aperture, upper mediastinum, subcarinal) were created. Four landmarks were identified: (i) the course of the thoracic duct in the mediastinum; (ii) the course of the left recurrent laryngeal nerve; (iii) the crossing of the azygos vein right and dorsal of the esophagus; and (iv) the position of the aortic arch, the pulmonary arteries, and veins.

CONCLUSIONS

The presented 3D reconstruction of unmanipulated human anatomy and schematic 3D 'boxes' provide a comprehensive overview of the surgical anatomy during the RACE or MICE. Our findings provide a useful tool to aid surgeons in learning the complex anatomy of the mediastinum and the exploration of new surgical approaches such as the RACE or MICE.

Isolated Posterior Mediastinal Thyroid Nodule Simulating Esophageal Pathology: A Multi-Modality Diagnosis

Posterior mediastinal goiter is not a common cause of dysphagia, and symptoms can simulate esophageal malignancy. This case report highlights two critical clinical aspects. First, the patient's symptoms of gradually worsening dysphagia to solids and liquids, odynophagia, and hoarseness of voice secondary to retrosternal thyroid nodule extension can simulate esophageal malignancy. Second, a barium swallow study can effectively rule out esophageal pathology even though more advanced studies, like High-resolution computed tomography (HRCT), are inconclusive. We present a unique case of isolated posterior mediastinal exophytic thyroid nodule simulating the symptoms of esophageal pathology.

Multimodality Image-Guided Embolization of Bronchial Artery Pseudoaneurysm in a Patient With Aortopathy

A 59-year-old man received an incidental diagnosis of a 5-cm right para-aortic mass that was initially thought to be of venous origin. Multimodality imaging revealed a right bronchial artery pseudoaneurysm that was treated with endovascular embolization. Bronchial artery pseudoaneurysms are extremely rare and can be fatal if ruptured. (Level of Difficulty: Advanced.)

A Case of Esophageal Duplication Cyst Identified on Cardiac Point-of-Care Ultrasound

ABSTRACT

Esophageal duplication cysts are rare congenital anomalies that are often symptomatic because of compression of surrounding structures. They are commonly diagnosed during childhood, with affected patients often presenting with abdominal pain or chest pain. Point-of-care ultrasound can be used as part of the emergency department evaluation of pediatric chest pain. We present a case of a 6-year-old boy who presented to the emergency department with worsening abdominal and chest pain, where point-of-care cardiac ultrasound identified a cystic structure in the posterior mediastinum.

Computed Tomographic Evaluation of Mediastinal Masses - An Experience at a Tertiary Care Centre in Bareilly, India

BACKGROUND Mediastinal lesions are one of the most common lesions of the chest in children and adults. Multidetector computed tomography (MDCT) is the most common investigation done in patients with suspected abnormalities on X-ray. Crosssectional imaging visualises complex anatomy, helps in predicting the tissue of origin, characterises lesions and depicts the extent of involvement of adjacent structures. Complications of mediastinal lesions and emergent conditions, for example, sealed pneumo-mediastinum, tracheoesophageal / pulmonary fistula, a peri-lesional abscess can be well assessed on CECT. The possibility of the lesion as benign or malignant and can be well predicted. Vascular lesions like aneurysms, dissections, and embolism can be evaluated and stable lesions requiring to follow up and unstable lesions requiring emergent treatment are differentiated using MDCT. The objectives of the study were to characterize and identify features pathognomic of specific mediastinal masses on computed tomography and find out diagnostic accuracy of MDCT in mediastinal masses and compare them with pathological results wherever possible. METHODS A prospective study was done in the Department of Radiodiagnosis, Rohilkhand Medical College and hospital, Bareilly for a span of 1 year from November 2018 to October 2019. Our study included 51 patients. Mediastinal lesions were assessed based on size, compartmental localisation, and attenuation and enhancement patterns. RESULTS In our study with 51 patients, 16 lesions were non-neoplastic and 35 were neoplastic lesions. Anterior mediastinal lesions constituted maximum lesions followed by middle and posterior mediastinal lesions. Lymph nodal masses were the commonest lesions out of which 4 cases were tubercular in origin, 4 were lymphomatous and 4 were metastatic. Neurogenic tumours were most common in the posterior mediastinum consisting of 6 cases. 2 vascular lesions were seen, 1 of aortic aneurysm and 1 aortic dissection. The diagnostic accuracy of MDCT was 93 % compared to histopathological results. Computed tomography (CT) plays a major role in evaluating mediastinal masses by virtue of its excellent multiplanar reconstruction capabilities and demonstration of exact anatomic relationships. However, in many situations, histopathological examination is needed to know the exact tissue of origin and for further management. CONCLUSIONS We conclude that CT has a major role in evaluating mediastinal masses regarding location, extent and tissue characterization. It can display certain features pathognomic for particular masses thus obviates the need for invasive procedures. KEY WORDS Mediastinal Lesions, MDCT, Imaging Modality, Histopathology

Paraganglioma with highly malignant potential involving the rib - Case report and review of the literature

Paragangliomas are rare neuroendocrine tumors arising from paraganglion cells in sympathetic or parasympathetic chains, which may develop in the abdomen, chest, skull base, and neck. As paragangliomas have a wide range of imaging features, the diagnosis often requires tissue sampling. We present a unique case of a paraganglioma which originally presented as a rib tumor.

A 64-year-old male with right flank pain for 2 months’ was referred for a noncontrast renal colic CT. He was found to have a 3.7 × 3.5 cm soft tissue mass invading the left posterior 9th rib and paraspinal muscle. This was fluorodeoxyglucose F 18, (¹⁸F-FDG) avid, with no other distant metabolic activity. He underwent ultrasound-guided core biopsy which revealed a diagnosis of paraganglioma. A right thoracotomy with chest wall resection of 8, 9, and 10 ribs were subsequently performed. The tumor was removed along with a small portion of adherent lung. The tumor was positive for CD56, synaptophysin and chromogranin. S-100 highlighted occasional sustentacular cells, consistent with a pathologic diagnosis of a paraganglioma. The patient remains symptom free for 6 months’ after the operation.

Our case highlights that, when paragangliomas occur within the chest wall, they may present as a rib tumor and can mimic metastasis, myeloma or other primary neoplastic etiologies originating from ribs. Both imaging and pathologic diagnosis can be challenging.

A comparison of computed tomography with magnetic resonance imaging for the diagnosis of thoracic extramedullary hemopoiesis in patients with leukemia: A non-inferiority retrospective diagnostic study

At present, MRI is the primary choice of examination for the diagnosis of thoracic extramedullary hemopoiesis. When thoracic extramedullary hemopoiesis presents as posterior mediastinum masses in specific clinical contexts, the diagnosis is not challenging. Other radiological presentations may be more difficult for diagnosis and require biopsy. Needle biopsy is typically preferred for the diagnosis of extramedullary hemopoiesis however, the high vascularization of tissues is one of the complications of this method thus, it is avoided. The aim of the present study was to compare the diagnostic parameters of CT with MRI for the diagnosis of thoracic extramedullary hemopoiesis in patients with leukemia, with an open lung biopsy as a reference standard. Chest CT, chest MRI and open lung biopsy data from a total of 912 patients with leukemia with a sign(s) and symptoms of suspected paravertebral and/or pulmonary extramedullary hemopoiesis were reviewed. In the present study, thoracic extramedullary hemopoiesis was defined as diffusivity of both lung fields being increased compared with the blood pool and no other abnormal focal of lungs being increased compared with the blood pool. The beneficial score was calculated for CT and MRI and plotted for the decision making of irradiation. With respect to open lung biopsy, MRI had a higher sensitivity compared with CT (0.865 vs. 0.809; P<0.0001; q=1691) however, CT had a higher accuracy compared with MRI (0.833 vs. 0.733; P<0.0001; q=3020). The low rate of overdiagnosis was observed for both methods for the detection of thoracic extramedullary hemopoiesis however, the working area for detecting thoracic extramedullary hemopoiesis at least once in images was higher for MRI compared with CT. CT and MRI both have diagnostic importance in the detection of thoracic extramedullary hemopoiesis in patients with leukemia however, chest MRI misdiagnoses the condition while CT can confirm it (level of evidence, 3).

Mediastinal epithelioid angiosarcoma arising in schwannoma: The first case in the literature

Angiosarcoma arising in a long-standing schwannoma is extremely rare and only a few cases were reported in the English literature. Besides tumors arising from vagus, sciatic or adrenal nerves, tumors growing on neck, foot or kidney were also described. To the best of our knowledge, in this article, we report the first mediastinal case occurring in longstanding schwannoma in a 53-year-old female patient. The patient was admitted to our clinic with severe dyspnea and palpitation. Her medical history showed a progressive right-sided paramediastinal mass which was first diagnosed in 2002. Three transthoracic needle biopsies performed in 2002, 2015 and 2016 were all non-diagnostic. An operation was suggested since 2002, but the patient has not accepted. Thorax computed tomography and magnetic resonance imaging revealed a huge mediastinal mass nearly fulfilling the right hemithorax. A diagnosis of "malign spindle cell tumor" was established with the last transthoracic biopsy and total surgical resection via posterolateral throcatomy was performed. Microscopically, tumor was composed of two components: a benign schwannoma and an epithelioid angiosarcoma. Endothelial and neural cell differentiations were confirmed immunohistochemically.

Assessment of paraspinal neurogenic tumors with diffusion-weighted MR imaging

PURPOSE

To assess paraspinal neurogenic tumors with diffusion-weighted MR imaging.

METHODS

Retrospective analysis was done upon 34 patients with paraspinal neurogenic tumors that underwent diffusion-weighted MR imaging. The ADC values of the mediastinal neurogenic tumors were calculated and correlated with biopsy results.

RESULTS

The ADC of benign paraspinal neurogenic tumors (1.5 ± 0.28 × 10^-3 mm²/s) was significantly higher (P = 0.001) than that of malignant peripheral nerve sheath tumors (0.995 ± 0.198 × 10^-3 mm²/s). Selection of 1.15 × 10^-3 mm²/s as a cut-off point for differentiating malignant from benign neurogenic tumors revealed an area under the curve of 0.885, an accuracy of 91.1%, a sensitivity of 90.9%, and specificity of 91.3%. There was significant difference (P = 0.04) in the ADC of schwannomas (1.55 ± 0.29 × 10^-3 mm²/s) from neurofibromas (1.33 ± 0.08 × 10^-3 mm²/s). The cut-off ADC value of 1.44 × 10^-3 mm²/s was used to differentiate schwannomas and neurofibromas with an area under the curve of 0.86, an accuracy of 82.6%, a sensitivity of 100%, and a specificity of 76.5%.

CONCLUSION

Diffusion-weighted MR imaging is imaging parameter that can be used for differentiation of benign from malignant paraspinal neurogenic tumors.

Imaging of spaces of neck and mediastinum by endoscopic ultrasound

Endoscopic ultrasound (EUS) of the mediastinum was pioneered by gastroenterologists, and it was taken up by pulmonologists when the smaller-diameter endobronchial ultrasound (EBUS) scope was designed after a few years. The pulmonologists’ approach remained largely confined to entry from the trachea, but they soon realized that the esophagus was an alternative route of entry by the EBUS scope. The new generations of interventionists are facing the challenge of learning two techniques (EUS and EBUS) from two routes (esophagus and trachea). The International Association for the Study of Lung Cancer (IASLC) proposed a classification of mediastinal lymph nodes at different stations that lie within the boundaries of specific spaces. These interventionists need clear definitions of landmarks and clear techniques to identify the spaces. There are enough descriptions of spaces of the neck and the mediastinum in the literature, yet the topic mentioned above has never been discussed separately. The anatomical structures, landmarks, and boundaries of spaces will be important to interventionists in the near future during performances of endosonography. This article combines the baseline anatomy of the spaces with the actual imaging during EUS.