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PubMedDate not supplied

Percutaneous biopsy of periarterial soft tissue cuffs in the diagnosis of pancreatic carcinoma.

Pancreatic cancer may present on computed tomography (CT) as an isolated cuff of tumor surrounding the superior mesenteric artery (SMA) or celiac trunk, without an identifiable pancreatic mass. We reviewed our experience with imaging-guided biopsy of the soft tissue cuff in this patient group. A retrospective review of our interventional database identified 163 patients referred for biopsy of suspected pancreatic carcinoma. Of these, eight patients underwent biopsy of an isolated cuff of soft tissue encasing the SMA (n = 6) or celiac trunk (n = 2). None of these eight patients had an identifiable pancreatic mass. The mean width of tissue cuff biopsied was 1.3 cm (range, 0.9-2.0 cm). Nine imaging-guided biopsies were performed in eight patients. Five biopsies were performed with color Doppler ultrasound and four with CT fluoroscopy. There was a median of two needle passes per procedure (range, 1-4). In six cases, a diagnosis of pancreatic adenocarcinoma was made at the first biopsy session. In one patient, ultrasound-guided biopsy was negative, but subsequent CT-guided biopsy was positive. In one additional patient with chronic pancreatitis, biopsy revealed benign fibrous tissue. There were no procedure-related complications. In patients with suspected pancreatic cancer (but without a focal parenchymal mass), imaging-guided biopsy of isolated periarterial tissue cuffs of tumor is accurate and safe.

Adenocarcinoma↗
PubMed2004

Giving form to the function of the heart: embedding cellular models in an anatomical framework.

A computational framework is presented for integrating the electrical, mechanical, and biochemical functions of the heart. The construction of efficient finite element representations of canine and porcine ventricular geometry and microstructure is outlined. Computational techniques are applied to solve large deformation soft tissue mechanics by using orthotropic constitutive laws for myocardial tissue and models of active tension generation embedded at the Gauss points in the finite element mesh. The reaction-diffusion equations governing electrical current flow in the heart are solved on a grid of deforming material points that access systems of ordinary differential equations representing the cellular processes underlying the cardiac action potential. Navier-Stokes equations are solved to predict coronary blood flow in a system of branching blood vessels embedded in the deforming myocardium.

Animals↗
PubMed1988

Magnetic resonance imaging of soft tissue masses.

Twenty-nine soft tissue masses were studied with magnetic resonance imaging (MRI) which proved to be useful in the preoperative evaluation of these lesions. Other imaging modalities employed had significant limitations. Plain films were of little value because of the intrinsically low contrast of soft tissues. Angiography was not necessary unless MRI suggested a vascular lesion or proximity to major blood vessels. Computed tomography (CT) and MRI both readily identified fatty lesions and their relationship to adjacent structures. Some soft tissue tumors could not be delineated from normal muscle with CT, but were easily seen with MRI. MRI is ideally suited for the study of suspected soft tissue tumors because of its excellent soft tissue contrast and its ability to image directly in any plane. Optimum evaluation required imaging in at least two planes with spin echo sequences chosen to bring out both T1 and T2 features.

Adolescent↗
PubMed1980

Radiological evaluation of orbital metastases, with emphasis on computed tomography.

Metastases to the orbit are found in the choroid, retrobulbar soft tissues, or bony orbit. Choroidal metastases result in retinal detachment and are best evaluated with fundoscopy and ultrasound. Retrobulbar metastases can involve both extraconal and intraconal spaces; they appear as masses having a high absorption value and irregular margins on plain CT scans and show slight contrast enhancement. The greater wing of the sphenoid is the most common site of bone metastases. These lesions often have soft-tissue components in both the lateral extraconal space of the orbit and the middle cranial fossa.

Breast Neoplasms↗
PubMed2002

Rapid expansion of benign scalp neurofibroma caused by massive intratumoral hemorrhage--case report.

A 62-year-old man with neurofibromatosis type 1 presented with rapid growth of a scalp mass. Head computed tomography demonstrated a large extracranial tumor of soft tissue density with massive intratumoral hematoma. Cerebral angiography demonstrated remarkable hypervascularity of the tumor. Preoperative embolization and total removal of the tumor was performed. The tumor contained a large amount of intratumoral hematoma (500 ml). The histological diagnosis was neurofibroma without malignant transformation. Benign scalp neurofibroma showing massive intratumoral hemorrhage is rare. Rapid growth or intratumoral hemorrhage in neurofibroma may be an indicator of malignant transformation.

Hemorrhage↗
PubMed2005

[Four cases of idiopathic retroperitoneal fibrosis markedly responsive to steroid therapy].

We report four cases of idiopathic retroperitoneal fibrosis (IRPF) effectively treated with steroid therapy. Computed tomographic (CT) scan showed the density of soft tissue mass enveloping the abdominal aorta in four cases. From radiographic findings we made a diagnosis of IRPF. Management with steroid therapy over three months improved general symptoms and radiographic findings. Prominent calcification in the wall of the abdominal aorta indicated that the arteriosclerosis was related to IRPF. We measured serum antibodies for Chlamydia pneumoniae in four cases.

Aged↗
PubMed2004

Healing, post-operative morbidity and patient perception of outcomes following regenerative therapy of deep intrabony defects.

AIM: This prospective multicenter randomized controlled clinical trial was designed to compare the clinical outcomes of papilla preservation flap surgery with or without the application of enamel matrix derivatives (EMD). This article reports on early healing events, post-operative morbidity and patient perceptions of the surgical outcomes. MATERIAL AND METHODS: One hundred and seventy-two patients with advanced chronic periodontitis and at least one intrabony defect of > or =3 mm were recruited in 12 centres in seven countries (European Research Group on Periodontology (ERGOPERIO)). Papilla preservation flaps were used to obtain access and primary closure. After debridement, and root conditioning, EMD was applied in the test subjects, and omitted in the controls. Healing was monitored 1, 2, 3, 4, 6 and 12 weeks after surgery. During the first 12 weeks of healing, supracrestal soft-tissue density was evaluated with a computer-assisted densitometric image analysis system (CADIA) using underexposed radiographs taken on a subset of 34 patients. Patient perceptions were evaluated with a questionnaire immediately after the procedure, at suture removal 1 week later and at 1 year. RESULTS: Subjects reported little intraoperative or post-operative pain or discomfort for both test and controls. Twenty-four percent of controls and 30% of tests (p=0.64) reported a degree of interference with daily activities for an average of 3 and 3.5 days, respectively. Post-surgical edema was noted in 25% of tests and 28% of controls. Wound dehiscence in the interdental portion of the flap was uncommon (14% of tests and 12% of controls at week 1) and of limited size. Root sensitivity was the most frequent post-operative adverse event: it affected 45% of test and 35% of controls (p=0.55). Up to 6 weeks post-operatively, soft-tissue densities were significantly higher in subjects treated with EMD with respect to controls. One year after completion of the surgery, patients reported high levels of satisfaction with the outcomes. The most frequently reported benefits included the ability to preserve a tooth/dentition and to maintain/improve chewing ability. The cost and need for frequent follow-ups were cited as significant drawbacks. CONCLUSIONS: This study portrayed the early healing events, pain, discomfort and adverse events of papilla preservation flap surgery and the 1-year patient perceptions of the benefits and disadvantages of periodontal surgery in intrabony defects. Earlier gains in soft-tissue density were observed following application of EMD. In terms of patient-centered outcomes, however, both procedures performed in a similar manner.

Alveolar Bone Loss↗
PubMed2001

Karyometric features differentiate early invasive cervical squamous cell carcinoma from preinvasive carcinoma.

The aim of the study was to investigate whether karyometric features reflect phenotypic change from preinvasive to early invasive squamous cell carcinoma of the cervix uteri. The material for the study was obtained from 12 patients diagnosed in the Chair of Pathomorphology. Each specimen contained both preinvasive and microinvasive lesions. The system of image acquisition and analysis consisted of a microscope coupled with a CCD camera and a PC computer. The software based on AnalySIS 3.0 system (Soft Imaging Systems GmbH) automatically detected cell nuclei and measured the preselected parameters. In each case 250 cell nuceli from both preinvasive and invasive components were analyzed. Significant differences in basic karyometric parameters were found both within individual cases and especially between groups studied. The present findings confirm the presence of early cytological changes at the onset of invasion. From the practical viewpoint the results suggest that karyometric features measured by image analysis might be used as a diagnostic tool, especially in cases where the diagnosis of microinvasion is difficult.

Carcinoma, Squamous Cell↗
PubMed2006

[Advances in soft tissue management in total knee arthroplasty. The use of imageless navigation systems].

Computer aided surgery has become established in the clinical routine over the past years. There are some very good studies which show that navigation optimizes reconstruction of the leg axis in total knee replacement. The question of why outliers occur in spite of navigation has to be asked. It is clear that total knee replacement is not only a bony procedure, but the soft tissues have an immense influence on postoperative stability of the prosthesis over the full range of movement. Current navigation systems allow visualization of the leg axis and size of the extension and flexion gap, and support the surgeon during soft tissue management. The current paper shows how the anatomic approach and the position of the patella influence soft tissue tension and support the surgeon during release of soft tissues in severe leg axis deformities.

Arthroplasty, Replacement, Knee↗
PubMed1999

Detecting hepatic lesions: the added utility of CT liver window settings.

PURPOSE: To prospectively evaluate the utility of adding computed tomographic (CT) liver windows to conventional soft-tissue windows for the detection of hepatic disease. MATERIALS AND METHODS: One of four radiologists experienced in abdominal imaging interpreted 1,175 consecutive abdominal CT scans from one institution. Hepatic images were first interpreted by using standard soft-tissue windows. The number of lesions and confidence in lesion detection were recorded. The liver-window images were then interpreted in conjunction with the soft-tissue-window images, and the number of lesions and confidence in detection were recorded again. The proportion of patients in whom additional lesions were found by using liver windows was determined. RESULTS: On soft-tissue-window and liver-window scans interpreted together, 869 (74%) patients had no hepatic lesions. Thirty-six (3.1%) patients had new lesions seen with the addition of liver windows. Twelve of these 36 patients had no lesions seen on soft-tissue-window scans. Twenty-six of the 36 patients with additional lesions seen had a history of neoplasm. There was a change in diagnosis in 1.7% of the patients with the addition of liver windows and a change in recommendation for follow-up in 0.85%. CONCLUSION: Routine interpretation of liver-window scans for all abdominal CT scans has limited added utility in detecting hepatic disease.

Adolescent↗
PubMed2006

A case with sinonasal teratocarcinosarcoma in the nasal cavity and ethmoid sinus.

Sinonasal teratocarcinosarcoma (SNTCS) is a rare and aggressive malignant neoplasm histologically characterized by the combination of one or more epithelial elements and mesenchymal components. We report a 61-year-old man with SNTCS involving left nasal cavity and ethmoid sinus. He complained of left epistaxis for 1 week. Computed tomography and magnetic resonance imaging revealed a soft tissue filling the left middle meatus and ethmoid sinus, and effusion in the left sphenoid sinus but no invasion to the orbit or skull base. Tumor was completely removed with lateral rhinotomy, and post-operative radiation therapy (Liniac 60 Gy) was performed. Follow-up examination for 3 years and 5 months after the radiation therapy has shown no evidence of recurrence or metastasis. This report describes his clinical course, etiology, diagnosis and management of SNTCS with a review of literature.

Carcinosarcoma↗
PubMed1995

CT doses in cylindrical phantoms.

A single CT scan of thickness T in a cylindrical phantom produces a three-dimensional dose distribution, which depends primarily on the photon energy spectrum, the x-ray beam shaping filter and the size and composition of the irradiated phantom. Monte Carlo simulations employing monoenergetic photons were employed to investigate the effect of each of these factors on phantom dose distributions. The fractional energies scattered, imparted and transmitted through the CT phantom were calculated. A dose index (D(r)), which is a function of phantom radius r, was computed. Phantom materials investigated included lung, fat, water, soft tissue, acrylic and bone with calculations performed for head (160 mm diameter) and body (320 mm diameter) phantoms. All dose and energy imparted data generated for CT phantoms were normalized using an 'in air' dose (Dair), which is defined as the axial dose (in acrylic) at the isocentre in the absence of any phantom. Results obtained show how CT parameters impact on doses in cylindrical phantoms. These dosimetry data are likely to be useful to estimate energy imparted to phantoms (and patients) undergoing CT examinations.

Biophysical Phenomena↗
PubMed2000

Enlargement of mandibular canal without hypesthesia caused by extranodal non-Hodgkin's lymphoma: a case report.

A rare condition of enlargement of the mandibular canal caused by an extra-nodal non-Hodgkin's lymphoma in a 59-year-old Japanese woman was reported. The patient had a swelling of the hard palate and protrusion of both ocular bulbs, which had been present for 10 years. A panoramic radiograph revealed that the right mandibular canal was widely enlarged, extending from the mandibular foramen to the mental foramen, without bone destruction. The continuous dilation of the mandibular canal to an approximate 15-mm width was associated with peripheral bony sclerosis. Computed tomography and magnetic resonance imaging showed a soft tissue tumor inside the mandibular canal. The lesion demonstrated expansive growth in the orbits, extending to the skull base through the superior orbital fissures and cavernous sinus. The lymphoma was suspected to have grown so slowly that the adjacent mandibular canal and ocular bulbs enlarged without destroying the normal bone and nervous tissue.

Dilatation, Pathologic↗
PubMed1982

[CT diagnosis of glomus-jugulare tumours].

Glomus-jugulare tumours (chemodectomas, non-chromaffin paragangliomas) are semi-malignant tumours arising from the glomus structures of the jugular bulb. They are soft tissue tumours which usually expand the jugular foramen and destroy its bony margins. Conventional methods of examination are therefore very effective. However, they only demonstrate the bone destruction and are therefore an indirect method for showing the tumour. The actual size and extent of the tumour, which are important for the surgeon or radiotherapist, cannot be demonstrated by simple x-rays. Computer tomography is very effective in the diagnosis of soft tissue lesions in the skull. CT is therefore of great importance in the diagnosis of glomus-jugulare tumours.

Female↗
PubMed1991

Malignant melanoma of the biliary tract: a case report.

A 58-year-old man was seen with obstructive jaundice and discomfort in the upper abdomen. Computed tomographic and ultrasound examinations revealed a soft-tissue mass in the gallbladder. Cholecystectomy and choledochotomy revealed a soft black mass in the gallbladder and a second one in the intrapancreatic portion of the common bile duct. Each was diagnosed as malignant melanoma. Subsequently, a Whipple resection of the pancreas, duodenum, and distal bile duct revealed a melanoma circumferentially invading and obstructing the distal common duct. No lymph node or distant metastasis was identified. Repetitive searches for another primary site have been negative. The tumor apparently originated in the biliary tract. The patient remains almost well 2 years after diagnosis.

Bile Duct Neoplasms↗
PubMed2003

An intratemporal facial nerve neuroma: a case report.

A forty-one-year-old man presented with right-sided progressive facial nerve paralysis of one year duration. Computed tomography of the temporal bone showed a soft tissue mass in relation with the tympanic segment of the facial nerve with destructive changes in the facial recess region. Magnetic resonance images before and after gadolinium injection revealed a contrast-enhancing mass lesion in the tympanic cavity. The tumor was removed through a transmastoid approach and a cable graft from the greater auricular nerve was used to repair the defect. Histopathologic diagnosis was facial nerve schwannoma. At the end of one-year follow-up, the patient had moderately severe facial nerve dysfunction.

Adult↗
PubMed1999

Comparison of perceptions of computer-animated left- and right-facing profiles.

PURPOSE: Although scientific publications differ in displaying left- or right-facing profiles, there are few systematic studies of the possible effects of directional biases and laterality on patients' and clinicians' perceptions of treatment need, outcomes, and satisfaction. As part of a research program to quantitate the physical bases of the perceived zone of acceptability and most-pleasing facial profiles, responses to computer-animated left- and right-facing soft-tissue profile images were compared and related to eye and hand preference. MATERIALS AND METHODS: Standardized left-facing, soft-tissue profile images were captured in color and digitized. The right-facing profile was created by reversing the left profile image to display a mirror image. Using imaging and customized morphing software, retrusive and protrusive extremes were created, from which transitional frames were developed to display five features of the soft-tissue profile: upper lip, chin, bimaxillary position, lower face height, and mandible. One left- and one right-facing profile for a Class II division 1 female, and Class III male were randomly presented to 24 subjects who were asked to indicate: 1) acceptability by pressing a mouse button and releasing the button when the images were no longer acceptable; and 2) most-pleasing image by pressing the mouse button once. RESULTS: No differences were found between left- and right-profile images for zone of acceptability, midpoint of the zone of acceptability, or most pleasing; nor was there any relation to laterality measures. However, consistently higher intercorrelations among the features for the zone of acceptability were found for the left- than for the right-facing profiles for retrusive to protrusive and protrusive to retrusive excursions measured in millimeters (p < .001). The bimaxillary position accounted for most of the variance in judgments of acceptability with greater influence on the left than on the right profile. CONCLUSION: With the increasing use of computer-imaging in dental practices, the influence of psychophysical and other environmental variables on perception must be considered.

Adolescent↗