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PubMed1982

The role of high resolution computed tomography in evaluating disease of the middle ear.

Successful temporal bone imaging demands appropriate modifications of the computed tomography (CT) scanner. While CT has been shown to be useful for demonstrating the detailed anatomy of the temporal bone, its role in the evaluation of middle ear pathology has not been investigated. Selective cases are presented to highlight the advantages of CT. Computed tomography is excellent in demonstrating soft tissue masses in the middle ear in inflammatory disease. It is also useful in accurately localizing bony fragments in trauma, as well as determining the status of the ossicles. Disease solely involving the tympanic membrane can be diagnosed on CT without subjecting the patient to surgical exploration.

Adult↗

PubMed2004

Musculoskeletal system.

Diagnostic imaging has played a major role in the evaluation of patients with cancers of the bone and soft tissue. The imaging modalities have included radiography, computed tomography, magnetic resonance imaging, and bone scintigraphy. Current experience suggests that functional imaging with positron emission tomography (PET) and [F-18]fluorodeoxyglucose (FDG) may also have an important role in the imaging evaluation of patients with bone and soft tissue sarcoma, including guiding biopsy, detecting local recurrence in amputation stumps, detecting metastatic disease, predicting and monitoring response to therapy, and assessing for prognosis. Prospective studies with large patient groups will be essential to define the exact diagnostic role of FDG PET in this clinical setting, which should also include an evaluation of the cost-effectiveness and the short-term and long-term benefits in clinical decision making and management. In this article, we review the diagnostic utility of dedicated PET and PET combined with computed tomography imaging system in the evaluation of patients with bone and soft tissue malignancies.

Bone Neoplasms↗

PubMedDate not supplied

Extra-nodal lymphoma presenting as a mimic of soft-tissue sarcoma.

BACKGROUND: A variety of soft-tissue tumours result in soft-tissue masses, which are all differential diagnoses of soft-tissue sarcomas. A rare cause is extra-nodal lymphoma which, unlike a soft-tissue sarcoma which it mimics, should not be excised, but rather treated by chemotherapy and/or radiotherapy. The aim of the present study was to identify clinical, radiological, biopsy and management features of lymphoma when presenting as a soft-tissue mass. METHODS: A review of 17 cases of soft-tissue lymphoma presenting as a soft-tissue mass from a total database of 295 soft-tissue tumours was undertaken. Lymphomas arising in cervical, axillary and inguinal nodes were excluded. RESULTS: All patients presented with a soft-tissue mass but none had the symptoms of lymphoma. Computed tomography scanning identified seven (54%) of 13 with regional lymphadenopathy, six (46%) of 13 with encasement of major vascular structures and three with invasion across major soft-tissue boundaries. Core biopsy established a diagnosis in 13 patients (sensitivity 93%). All patients were treated with either chemotherapy and/or radiotherapy and all are alive with a mean follow up of 19 months. None underwent major resectional surgery. CONCLUSION: The present series highlights a rare subgroup of patients with extra-nodal soft-tissue lymphoma mimicking soft-tissue sarcoma. Core biopsy is accurate in their diagnosis. Computed tomography scanning may show features suggesting the diagnosis.

Adult↗

PubMed2004

How predictable is orthognathic surgery?

There are a number of increasingly sophisticated techniques available for orthognathic treatment planning. All are based on the determination of the skeletal pattern and the position of the dentition. However, they all suffer from difficulties associated with predicting the soft tissue profile. The aim of this retrospective cephalometric investigation was, therefore, to compare the ability to predict accurately the outcome of orthognathic treatment using the 'hand planning' technique and the orthognathic planning and analysis (OPAL) computer program, with an emphasis on the soft tissue profile. Seventy adult subjects were divided into two groups not specific for gender or age: the Class III patients had undergone bimaxillary surgery and the Class II patients sagittal split mandibular advancement. In each group, the pre-treatment and post-debond lateral cephalograms were utilized to calculate the actual orthodontic and surgical movements. These values were then used to produce a prediction using both the hand planning technique and the OPAL program. The resultant predictions were digitized using a customized computer program and compared with the actual outcome. The results show that there was marked individual variation when planning by hand and using the OPAL program. In the mandibular surgery group, hand planning and OPAL were of similar accuracy and few points differed significantly between prediction and outcome. However, for the bimaxillary group, a number of points showed bias and the hand planning technique appeared to be more accurate than the OPAL program, particularly in the region of the lips. Although the usefulness of predictions is acknowledged, these results suggest that they should be used with a certain amount of caution.

Adult↗

PubMed1985

[Computed tomographic diagnosis of liposarcoma].

One hundred and eighty-two fat-containing soft tissue tumours have been found in 27 400 CT examinations. Amongst these there were 22 malignant liposarcomas. CT is unable to give a tissue diagnosis but, nevertheless, provides some important criteria which make it possible to differentiate benign lipomas from lipomatous tumours, particularly liposarcomas, which require surgical intervention.

Adult↗

PubMed1995

Surgical correction of skeletal Class III malocclusions using cranial base length (corrected and uncorrected) as a reference.

This study was an attempt to show how a variation in the anteroposterior position of nasion, or length of the anterior cranial base, when used as a reference line, affects the esthetic outcome of surgically repositioned bony bases. Five white female subjects exhibiting a short anterior cranial base and characterized by maxillary retrusion were included in this study. Lateral cephalograms and 35-mm photographs of each subject were digitized into a computer imaging system, and computer-simulated surgical procedures were performed. Soft tissue profiles were then generated to reflect the skeletal changes that took place. When three groups of respondents were asked to choose the most pleasing profile, the majority (65%) chose the maxillary (Le Fort I) surgical procedure, in which the cranial base was extended to a range of corrected "normals." These results indicate that when cephalometrics are used to formulate a diagnosis and treatment plan, the most esthetic result may be obtained if the landmarks that are important to the analysis, in this case, the anterior cranial base length, are normalized.

Cephalometry↗

PubMed1987

Inferior pulmonary ligament lymphadenopathy: demonstration by computed tomography.

Inferior pulmonary ligament lymphadenopathy is common in bronchogenic carcinoma and may also occur in lymphoma and potentially in any condition which may cause intrathoracic lymphadenopathy. Despite the apparent frequency with which inferior pulmonary ligament lymphadenopathy occurs, we have been unable to find a description of the computed tomographic findings of this condition. In a patient with lymphoma, we found inferior pulmonary ligament lymphadenopathy by computed tomography as an oval, elongated soft-tissue density arising within the inferior pulmonary ligament and still attached to the mediastinum by a piece of the normal ligament. We believe that this appearance should be sufficient for the correct computed tomographic diagnosis of inferior pulmonary ligament lymphadenopathy.

Aged↗

PubMed2004

Synovial chondromatosis of the acromioclavicular joint.

A 53-year-old woman presented with swelling of 3 years' duration on the right anterior chest wall. A radiograph showed coarse calcifications around the subclavicular region and erosion of the ipsilateral acromioclavicular joint. Computed tomography also showed calcifications in soft tissue. Magnetic resonance imaging revealed a tumor around the clavicle extending to the anterior aspect of chest wall, which had low signal intensity on T1-weighted imaging and high signal intensity on T2-weighted imaging. The histologic findings were of a hyaline cartilage-like mass consisting of mature chondrocytes and an extracellular matrix. The histologic diagnosis of synovial chondromatosis was made. The present case is unusual in respect of the location and size of the tumor.

Acromioclavicular Joint↗

PubMed2002

Chondrosarcoma of the larynx: treatment with radiotherapy.

The case of a 50-year-old man with chondrosarcoma of the larynx treated with radiotherapy is reported. The patient presented with hoarseness and dyspnea. He underwent computed tomography (CT), which demonstrated a soft tissue mass of the larynx. Direct laryngoscopy with biopsy established the diagnosis of chondrosarcoma. Although experience with radiotherapy in these cases has been lacking in the literature, it was considered and eventually used, as radical surgery would result in severe cosmetic and functional impairment. Radiation therapy alone resulted in long-term remission of the tumour for more than 3 years. The patient has been followed up using CT and direct laryngoscopy for early detection of recurrence or metastases.

Chondrosarcoma↗

PubMed1992

Sclerosing hemangioma of the lung: radiographic and pathological study.

The clinical, radiographic, and pathological features of 10 patients with sclerosing hemangioma of the lung seen between 1974 and 1990 were reviewed. The incidence of sclerosing hemangioma was 22.2% of benign tumors surgically resected during that time. There were 2 male and 8 female patients aged 15 to 77 years at operation, and 9 patients were asymptomatic. All 10 patients had a solitary tumor with a well-defined homogeneous round or oval shadow on chest roentgenograms. Chest computed tomography revealed a homogeneous soft-density mass in 4 patients and a low-density portion within the tumor because of a cystic change in 1 patient. Microscopically, 5 patients had a preponderantly solid pattern, 3 had a preponderantly papillary pattern, and 1 patient had a preponderantly sclerotic pattern. One patient had an equal mixture of solid and papillary patterns. Nine of the 10 tumors consisted of a mixture of at least three of the four major patterns. Regarding treatment, thoracotomy is indicated for a definite diagnosis. If a benign tumor is suspected at operation, an intraoperative frozen section is recommended. Once the diagnosis has been established as sclerosing hemangioma, a limited resection is indicated.

Adolescent↗

PubMed1997

Imaging findings of lipomas in the orofacial region with CT, US, and MRI.

OBJECTIVE: The aim of this study was to document retrospectively the imaging findings of lipomas with the use of computed tomography, ultrasonography, and magnetic resonance imaging. STUDY DESIGN: Thirteen patients with 11 lipomas and 2 lipomatoses were evaluated. Eleven cases were examined by computed tomography, 9 by ultrasonography, and 3 by magnetic resonance imaging. RESULTS: Lipomas had a density ranging from -134 to -83 Hounsfield units, (mean-108) on the computed tomography images. The margins were ill defined in 9 of 10 cases. The superficial muscles were displaced externally in 8 cases and internally in 2 cases. With ultrasonography, 8 lesions were hypoechoic, and one was hyperechoic. All three lesions had a high signal intensity on both T1- and T2-weighted images. CONCLUSIONS: Lipomas had a specific range of computed tomography Hounsfield unit values and also displaced the surrounding soft tissue. Although some variation in the ultrasonographic appearance was observed, the lesions tended to be hypoechoic. These findings may be useful for diagnosing lipomas in the orofacial region.

Adolescent↗

PubMed1995

Orbital barotrauma.

A 24-year-old man sustained orbital and facial injury when an industrial suction device attached to his face. Hemorrhage and edema within the orbital soft tissues were clinically evidenced by proptosis and restricted ocular motility and confirmed by computed tomography. No retinal hemorrhages or exudates were noted. Orbital soft tissue injury caused by sudden extreme decrease in extravascular atmospheric pressure (i.e., orbital barotrauma) is not well described in the ophthalmic literature. The findings in our case are remarkably similar to those seen with traumatic asphyxia and the ophthalmological hydrostatic pressure syndrome, two conditions attributed to an increase in intravascular pressure. Physiologically, our case and these conditions share a similar increase in transmural pressure at the capillary level that is responsible for fluid transudate and hemorrhage in the orbital soft tissues. Intraretinal hemorrhages and exudates typical of Purtscher's retinopathy were conspicuously absent in our patient.

Adult↗

PubMed2001

Columnar-cell carcinoma of the thyroid.

A case of columnar-cell carcinoma of the thyroid gland occurring in a 77-year-old female is described. Tracheal deviation and calcified anterior neck lesion were showed in X-ray examination. A computed tomography (CT) scan revealed a soft tissue density mass with calcification of the right thyroid lobe and isthmus. A (99m)Tc scintiscan showed a 'cold' nodule, whereas a (201)Tl scintiscan showed a 'hot' in the right thyroid lobe and isthmus. Subtotal thyroidectomy and dissection of paratracheal adipose tissue were performed after fine needle aspiration cytology (FNA) of the thyroid mass had been done. On the FNA smears, there were many papillary fragments, which contained pseudostratified columnar cells. Histopathologically, the tumor had three different types of neoplasm including papillary carcinoma of usual feature, columnar-cell carcinoma and follicular carcinoma. Transitional changes were observed between columnar-cell carcinoma and follicular carcinoma. The patient has been followed up for 3 years, with no evidence of recurrence or metastasis.

Aged↗

PubMed2004

Sarcoma of follicular dendritic cells in the dorsal mediastinum.

Follicular dendritic cell sarcomas (FDCSs) are very rare and usually originate in lymph nodes. We report an exceedingly rare case with localization in the dorsal mediastinum and, for the first time, provide positron emission tomography (PET) data for this tumor. This report describes the case of a 76-year-old man with a clinically aggressive tumor in the dorsal mediastinum. Computed tomography scan revealed displacement of soft tissue and lymph nodes. PET showed that the tumor had a high proliferation rate. Investigation of the successfully removed tumor mass revealed reactivity of the tumor cells for follicular dendritic cell markers and desmosomes linking adjacent tumor cells at the ultrastructural level. Marked atypia, a high mitotic rate, and areas of coagulative necrosis were found. The tumor in our case revealed the typical features and thus was classified as FDCS. In contrast to previous reports in the literature, preoperative imaging, histology, and immunohistochemistry studies indicated at least an intermediate degree of malignancy. Nevertheless, the patient made a good postoperative recovery and remained apparently disease-free 2 years later.

Aged↗

PubMed2005

Squamous papillomatosis of the bilateral nasal cavities.

The term "papillomatosis" indicates the tendency towards multicentricity and recurrence that these tumors exhibit (Snyder et al. 1972). A typical squamous papilloma arises from the nasal vestibule and is characterized by the epithelial proliferation growing an exophytic manner. We report a rare case of squamous papillomatosis of the bilateral nasal cavities. A 65-year-old man presented with a 2-year-history of bilateral nasal obstruction. Computed tomographic (CT) scans revealed a soft density mass in the bilateral nasal cavities and ethmoid sinuses. Because the tumors were limited to the nasal cavities and anterior ethmoid sinuses, total removal of the tumors was performed endoscopically. On the basis of the clinicopathological findings, the tumors were diagnosed as squamous papillomas. His post-operative course was uneventful, and he is currently free from disease 13 months after surgery. Nasal papillomas usually arise from the unilateral nasal cavity or paranasal sinus. While some cases of inverted (inverting) papillomas arising from the bilateral nasal cavities have been reported, bilateralism of the nasal squamous papillomas is quite rare. Diagnosis, clinical behavior and treatment of squamous papillomatosis of the bilateral nasal cavities are reviewed.

Aged↗

PubMed2005

Clinics in diagnostic imaging (102).

A 19-year-old man presented with cough and haemoptysis of ten days duration. He also had mild right hypochondrial pain. Chest radiograph and computed tomography (CT) showed a rounded soft tissue density opacity with an air crescent sign. CT showed multiple cystic lesions in the liver with a daughter cyst in its lateral wall. Diagnosis of hydatid disease of lung and liver was made. The contents of the liver cyst were aspirated, hypertonic saline instilled, re-aspirated, and absolute alcohol injected. Hydatid disease is endemic in certain parts of the world. Although the lungs and liver are most frequently affected, the disease can arise in any part of the body and should be kept in differential diagnosis whenever a cystic lesion is encountered. Hydatid cysts typically demonstrate characteristic imaging findings, however, the appearances may become complicated due to cyst rupture or secondary infection. Ultrasonography is the imaging modality of choice particularly in hepatic disease. CT best demonstrates cyst wall calcification and cyst infection.

Adult↗

PubMed1992

Intracranial osteolytic malignant meningiomas appearing as extracranial soft-tissue masses.

Malignancy is rare in intracranial meningiomas. Although the topic is widely discussed, there is little agreement in the literature as to the histological and radiological features that warrant the diagnosis of malignant meningioma. Three patients are described who had soft-tissue masses and underlying osteolytic lesions on computed tomography. All three patients also had a large intracranial component that proved to be a malignant meningioma. Rarely do meningiomas have all three of these features. We propose that a meningioma causing osteolysis and soft-tissue extension should be considered malignant until proven otherwise.

Aged↗

PubMed2003

Evaluation of F18-deoxyglucose positron emission tomography (FDG-PET) to assess the nature of neurogenic tumours.

AIMS: Benign neurofibromas and malignant peripheral nerve sheath tumours (MPNST) commonly develop in patients with neurofibromatosis. Differentiation of benign from malignant tumours by conventional preoperative imaging is unreliable. FDG-PET is a non-invasive technique for biological tumour evaluation. The aim of this study was to assess the value of FDG-PET in patients with neurogenic tumours suspicious for MPNST. METHODS: Benign and malignant neurogenic soft tissue tumours were prospectively evaluated by computed tomography or magnetic resonance imaging. Three-dimensional qualitative and quantitative FDG-PET was performed. Standard uptake value (SUV) was analyzed with respect to histological diagnosis and follow-up data. RESULTS: Twenty-five neurogenic soft tissue tumours were included. FDG-PET identified all primary (n=6) and recurrent MPNST (n=7). Benign lesions (n=12) did not demonstrate high FDG uptake. The SUV was significantly higher in MPNST (median 2.9; range 1.8-12.3), than in benign tumours (median 1.1; range 0.5-1.8) (p<0.001). At a cut-off value of 1.8 SUV measured 1 h post-injection FDG-PET distinguished between MPNST and benign neurogenic tumours with 100% sensitivity and 83% specificity. CONCLUSIONS: FDG-PET allows discrimination of benign from malignant neurogenic tumours. This should be particularly useful in patients with neurofibromatosis as FDG-PET may help to avoid multiple surgical procedures for benign tumours.

Adult↗