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PubMed1994

Parapharyngeal teratoma in the newborn.

A parapharyngeal teratoma in a newborn was the cause of acute respiratory distress, which was relieved by tracheostomy. Subsequent investigations by soft tissue x-rays of the neck, computed tomography, and examination under anesthesia defined the anatomic location of the tumor, its extent, and its likely nature. The tumor was removed completely by the transcervical approach. Mandibulotomy was not required. Histological examination showed the presence of a large amount of mature brain tissue, a moderate amount of collagenous fibers and smooth muscle cells, and a minute amount of cartilage and epithelial structures. The postoperative course was satisfactory. No recurrence was seen 6 years after surgery. The computed tomography scan was found to be the most useful investigative method. To the authors' knowledge, this is the first comprehensive report of a teratoma occupying the parapharyngeal space in a newborn.

Female↗

PubMed1983

Transsphenoidal encephaloceles.

Transsphenoidal encephaloceles are rare congenital anomalies that may be immediately apparent in infants that present with multiple cranial midline defects. They should also be suspected in patients presenting with cerebrospinal fluid rhinorrhea, an epipharyngeal soft tissue mass, a visual defect, or an endocrinologic disturbance, especially when associated with midfacial and optic nerve anomalies. Plain x-ray films of the skull may show absence of the sellar floor and a soft tissue mass; the diagnosis is confirmed by computed tomography scanning. Surgical therapy may be indicated for persistent cerebrospinal fluid rhinorrhea, symptomatic epipharyngeal respiratory distress, or progression of neurological deficits. Two cases of transsphenoidal encephalocele are reported.

Adult↗

PubMedDate not supplied

MRI differentiation of recurrent nasopharyngeal carcinoma from postradiation fibrosis.

A prospective study was performed to determine the usefulness of magnetic imaging (MRI) in differentiating local recurrence versus post-irradiation fibrosis in 72 patients after radiotherapy of nasopharyngeal carcinoma (NPC). All patients had a soft-tissue mass in the nasopharynx demonstrated by computed tomography. A total of 29 patients had tumor recurrence; 40 patients had only radiation fibrosis; 1 patient had postradiation edema and 2 patients had inflammatory changes. Based on the differences in signal intensity on T2-weighted images, MRI may be promising as a noninvasive method for differentiating radiation fibrosis from local recurrent NPC. However, the signal intensity pattern of the tumor is not specific and may be seen in radiation edema and infection.

Adult↗

PubMed2005

Bilateral occipital condyle fractures leading to retropharyngeal haematoma and acute respiratory distress.

Injuries to the occipito-cervical junction are rare and not easily diagnosed on conventional radiographs. The authors report such a case where the diagnosis was delayed. The patient developed a significant retrophyarngeal haematoma resulting in acute respiratory distress and required emergency endotracheal intubation. The patient remained intubated for five days and received a tapered dose of intravenous dexamethazone to reduce swelling in the proximity of the airway. At six weeks the patient had developed a left hypoglossal nerve palsy that persisted at 12 months. Occipital condyle fractures and the difficulties of diagnosis are discussed. The importance of measuring pre-vertebral soft tissue swelling on lateral radiographs is emphasized. Computed tomography of the C0-C2 region should be performed to identify base of skull and upper cervical fractures.

Accidents↗

PubMed1993

Image processing of videofluoroscopy of patients with velopharyngeal insufficiency and hypernasal speech.

Eleven patients with hypernasal speech and velopharyngeal insufficiency (VPI), together with five normals, were evaluated by videofluoroscopy to assess velopharyngeal movement, velar lift and lateral pharyngeal wall movement. Computer processing of the images obtained was used to compensate for initial poor quality images by contrast and edge enhancement techniques and to provide objective measurement of the movements involved. It was demonstrated that objective computer aided analysis of videofluoroscopic images is feasible and may provide additional subtle diagnostic information when nasendoscopy is unavailable. In addition, results obtained showed an increased degree of velar lift and lateral pharyngeal wall movement for the more severely affected patients. These suggest a compensatory mechanism in operation for the more severe cases of VPI.

Child↗

PubMed1986

Subperiosteal osteoid osteoma of the talus.

We report three patients with subperiosteal osteoid osteoma of the talus. All showed an erosion of the dorsal surface of the talus with medullary bone sclerosis. Adjacent paraosseous soft tissue calcification was seen in two lesions. Computed tomography demonstrated the nidus of the osteoid osteoma in two cases.

Adolescent↗

PubMed2002

Postmenopausal intravenous leiomyomatosis with high levels of estradiol and estrogen receptor.

BACKGROUND: Intravenous leiomyomatosis is a rare variant of leiomyoma. CASE: The patient was a 49-year-old gravida 3, para 3 woman with menopause at age 46. She presented with a history of syncope. Vaginal examination revealed an enlarged and elastic-soft mass of the uterus. A pelvic ultrasound, computed tomography scan, and magnetic resonance imaging showed a heterogeneous, irregularly shaped 8- to 10-cm tumor. In addition, the inferior vena cava was almost completely occluded. Cardiac ultrasound demonstrated a mobile mass in the right atrium. The serum estradiol was 208 pg/mL (normal 0-59). Intravenous leiomyomatosis with cardiac extension was diagnosed preoperatively. A resection of the intracardiac and intracaval mass and a subtotal hysterectomy with bilateral salpingo-oophorectomy were performed. The uterine tumor weighed 600 g, and the cordlike intravascular tumor extending from the internal iliac vein into the right ventricle was 40 cm long and weighed 60 g. Pathologic examination confirmed intravenous leiomyomatosis with no evidence of atypia. The level of estrogen receptor in the tissue was 140 fmol/mg protein. The postoperative course was uneventful, and she has been in good health for 17 months after the operation. CONCLUSION: We report a case of intravenous leiomyomatosis extending into the right ventricle treated with a one-stage operation. It is possible that a high concentration of serum estradiol and high level of tissue estrogen receptor are related to the intravenous leiomyomatosis.

Estradiol↗

PubMed2000

Organic change of effusion in the mastoid in otitis media with effusion and its relation to attic retraction.

To try to solve the pathogenesis of severe attic retraction viewed from mastoid condition, we examined the residual soft tissue density (RSTD) in the mastoid by computed tomography (CT) in 85 patients (107 ears) with otitis media with effusion (OME) 3 months after tympanostomy tube insertion or later. The incidence of RSTD in the mastoid was significantly higher in OME of adults (52.6%) than in children (24.1%). Ears with severe attic retraction had RSTD significantly more frequently (80%) than those with no or mild attic retraction, and many of the mastoids with severe attic retraction were occupied totally by RSTD. The area of the mastoid (mastoid pneumatization) was significantly smaller, and CT density of the mastoid (sclerotic tendency) was significantly higher in ears with RSTD than in those without. RSTD after tympanostomy tube insertion in the mastoid indicating organic change of effusion was considered one of the important factors relating to the pathogenesis of severe attic retraction.

Adolescent↗

PubMed2003

System for upper airway segmentation and measurement with MR imaging and fuzzy connectedness.

RATIONALE AND OBJECTIVES: The purpose of this study was to evaluate whether a computerized system developed to help delineate the upper airway and surrounding structures with magnetic resonance (MR) imaging was effective for aiding in the diagnosis of upper airway disorders in children. MATERIALS AND METHODS: The authors performed axial T2-weighted MR imaging to gather information about different aspects of the airway and its surrounding soft-tissue structures, including the adenoid and palatine tonsils, tongue, and soft palate. Images were processed and segmented to compute the architectural parameters of the airway (eg, surface description, volume, central [medial] line, and cross-sectional areas at planes perpendicular to the central line). The authors built a software package for the visualization, segmentation, registration, prefiltering, interpolation, standardization, and quantitative analysis of the airway and tonsils. RESULTS: The system was tested with 40 patient studies. For every study, the system segmented and displayed a smooth three-dimensional rendition of the airway and its central line and a plot of the cross-sectional area of the airway orthogonal to the central line as a function of the distance from one end of the central line. The precision and accuracy for segmentation was 97%. The mean time taken per study was about 4 minutes and included the operator interaction time and processing time. CONCLUSION: This method provides a robust and fast means of assessing the airway size, shape, and level of restriction, as well as a structural data set suitable for use in modeling studies of airflow and mechanics.

Algorithms↗

PubMed2006

Intrathoracic paraspinal malignant peripheral nerve sheath tumor.

Schwannoma is the most common nerve sheath tumor in the posterior mediastinum, whereas intrathoracic paraspinal malignant peripheral nerve sheath tumor (MPNST) is quite rare. Both benign and malignant nerve sheath tumors may be symptomatic, rendering clinical differentiation of limited utility. On radiographic imaging, erosion of the ribs and vertebral bodies, irregularity in contour, and inhomogeneity in attenuation are not sufficiently reliable for diagnosis of MPNST. Histologically, MPNSTs reveal hypercellularity, nuclear atypia, and mitotic activity. Surgical resection is the main modality of treatment. Postoperative radiation therapy for MPNST has led to a significant reduction in local recurrence. The prognosis is unfavorable. Herein, we present an unusual case of a posterior mediastinal mass in a 50-year-old female with delayed diagnosis of 2 years. After surgical intervention, the histologic finding was MPNST. Postoperative radiation therapy was applied because of incomplete resection. The follow-up chest computed tomography 5 months later revealed a residual soft tissue mass with significant reduction in size over the parathoracic spine area. No neurologic sequelae were identified after surgery.

Female↗

PubMed1987

Comparison of cineradiographic and photodetection techniques for assessing velopharyngeal function during speech.

This study investigated the extent to which high-speed lateral-view cineradiography and a photodetector system described by Dalston (1982) provided comparable information concerning velopharyngeal activity. We observed the production of isolated utterances and running speech for 2 subjects in three contexts. A comparison was made between the times at which the velopharyngeal port was observed by each method to begin opening, reach maximal opening, begin closing, and initially attain closure. The photodetector system was found to be sensitive to changes in velar position observed by cineradiography. The correlation between the magnitude of photodetector output and the magnitude of velar displacement from the posterior pharyngeal wall was .89 for Subject 1 and .78 for Subject 2. The lack of a perfect relation between the output of the photodetector device and movements of the velum observed by cineradiography was not unexpected given the two-dimensional limitation of lateral cineradiography and the complexity of events associated with changing port size. The significance of these findings is discussed with respect to the potential research and clinical uses of this photodetector system.

Cineradiography↗

PubMed2001

Neurofibromatosis involving the urinary bladder.

We present two interesting cases of a 24-year-old man and a 14-year-old boy, uncle and nephew, with lower urinary tract symptoms, café au lait patches and subcutaneous nodules. Ultrasonography and computed tomography scans showed a large, irregular lobulated soft tissue mass between the bladder and sacrum. Cystoscopy, laparotomy and biopsies revealed neurofibromatosis involving the urinary bladder. No enlargement of the tumor or upper urinary tract obstruction has occurred during the long-term follow up. We recommend meticulous follow up of patients with giant intrapelvic neurofibromatosis.

Adolescent↗

PubMed2004

[The interesting case -- case no. 65].

Bilateral Osteomyelitis following frontal sinusitis is a rare complication in the antibiotic era. The main risk of a progredient course is mainly the formation of external subperiostal, epidural, subdural abscesses or brain abscesses with potentially life-threatening complications. This is a report on a patient who presented in our department with progredient cephalgia and swelling in the area around the glabella and frontal sinus. Macroscopical examination revealed septum deviation to the right side and nasal polyposis of the right nasal passage. A computed tomography of the paranasal sinuses showed subtotal soft tissue obstruction of all sinuses with the exception of the sphenoidal sinus. Bilateral osteolysis of the ventral osseous borders of the frontal sinus with accompanying osteosclerosis was also observed. The therapy consisted of radical frontal sinus surgery via Unterberger approach. This case demonstrates a rare case of bilateral frontal osteomyelitis together with the necessary diagnostic and therapeutic measures. The management consisted of the removal of all osteomyelitic bone and antibiotic therapy. Differential diagnostic procedures must be carried out in order to exclude orbital and intracranial complications. Regular follow-up examinations and a CT scan of the paranasal sinuses are part of the standard therapy.

Adult↗

PubMed1989

[How can one recognize a velum snorer?].

In ten habitually snoring subjects and ten patients with obstructive sleep apnea syndrome, preoperative snoring sounds above a preset sound pressure level were recorded and a frequency spectrum analysis by means of time series Fast Fourier Transformation was performed. All patients underwent uvulopalato-pharyngoplasty after which the snoring sounds were recorded again and analysed under the same conditions. Preoperative frequency spectra in heavy snorers were dominated by a component which results from the movement of the soft palate and uvula and which presents as a low-frequency vibration of 25 to 50 c/s and its harmonics up to several hundred c/s. After UPPP the sound pressure level of the snoring noise in heavy snorers was reduced by 20 to 30 decibels and could not be recorded any more. The frequency spectrum of snoring noises in patients with obstructive sleep apnea syndrome differed from those of heavy snorers. In apnea patients the snoring noise usually consisted of other and higher frequency components which masked the vibration of the soft palate and uvula to a more or less high degree. An extreme degree of masking is reached in snoring noises following apneic episodes when identification of the movement of the soft palate is impossible. After performing UPPP in an apneic patient the low-frequency content of the spectrum below about 400 Hz was reduced dramatically but higher frequency parts were still present. This resulted in only minor reduction of snoring noise sound pressure level. Our results are in agreement with other authors in showing that UPPP is not successful when the site of obstruction is not in the velo-pharyngeal plane.(ABSTRACT TRUNCATED AT 250 WORDS)

Airway Obstruction↗

PubMed1988

[The use of contrast media in magnetic resonance tomography of head and neck tumors].

The ranking of MRT was evaluated retrospectively in 37 patients with clinically confirmed malignant neoplasms of the head and neck. The results were compared with the clinical and endoscopic findings and with computed tomographic scans (CT). MR consistently showed superior soft tissue definition and extent of disease compared with CT. However, the sensitivity of both methods was comparably high. With the exception of tumours of the floor of the mouth and the anterior third of tongue the use of paramagnetic contrast material improved image quality compared with T2-sequences. MRT was superior to CT in imaging the post-treatment head and neck. Even here, contrast enhanced T1-images improved contrast between recurrent tumour and adjacent soft tissues, although in some cases false positive diagnosis was caused by postradiation oedema and inflammatory changes.

Adolescent↗

PubMed2002

Updating of form factor tabulations for coherent scattering of photons in tissues.

An updating of photon transport modelling in tissues is carried out by including the effect of molecular interference in the coherent (Rayleigh) scattering. To this end, the present tabulations--which permit us to obtain the linear differential scattering coefficient of compounds from a simple weighted sum of the elemental components--are integrated by adding files for a limited set of molecular interference functions. This set originates from a four-component model which is found to be capable of reproducing human tissues in situations involving bony and soft tissues. The proposed procedure overcomes, in the computation, the hindrance that the dependence on molecular interference effects leads every tissue to have its own diffraction pattern, which is not easily obtained by means of measurements or calculations.

Algorithms↗

PubMed2006

Utility of positron emission tomography in sarcomas.

PURPOSE OF REVIEW: Positron emission tomography using [18F]fluoro-2-deoxy-D-glucose has been studied as a tool to help predict the malignant potential of sarcomas, prognosis of patients and response to chemotherapy, and to detect disease recurrence. Recent developments in the use of [18F]fluoro-2-deoxy-D-glucose positron emission tomography in the clinical management of patients with suspected or diagnosed sarcomas are presented. RECENT FINDINGS: [18F]fluoro-2-deoxy-D-glucose positron emission tomography should not be used in lieu of histology to diagnose sarcomas, but may aid in biopsy planning. [18F]fluoro-2-deoxy-D-glucose positron emission tomography should not replace magnetic resonance imaging and computed tomography imaging for staging or surveillance. In soft tissue sarcomas, [18F]fluoro-2-deoxy-D-glucose uptake correlates with histologic grade and risk of tumor recurrence. Reduction in [18F]fluoro-2-deoxy-D-glucose uptake is an early predictor of histologic response of osteosarcoma, Ewing's and soft tissue sarcomas to chemotherapy, and has correlated with clinical outcomes in Ewing's, soft tissue sarcomas and gastrointestinal stromal tumor. SUMMARY: [18F]fluoro-2-deoxy-D-glucose positron emission tomography will likely play increasingly important prognostic and predictive roles in the management of sarcomas. Available data suggest that positron emission tomography is useful clinically in predicting response to therapy early in the course of treatment for both cytotoxic chemotherapy and kinase inhibitors. Additional study to determine the optimal semiquantitative measure of [18F]fluoro-2-deoxy-D-glucose accumulation in sarcoma and standardization of positron emission tomography methods is needed.

Fluorodeoxyglucose F18↗

PubMed2004

Primary carcinoid tumor arising in a retroperitoneal mature teratoma in an adult.

An extremely rare case of a primary carcinoid tumor arising in a mature retroperitoneal teratoma is reported. A 53-year-old woman was admitted for further examination of an incidental retroperitoneal mass with calcification. Computed tomography scans demonstrated a tumor with fat, soft tissue and bone densities on the left renal hilum. Surgical excision of the tumor was performed with a preoperative diagnosis of retroperitoneal teratoma. The pathological diagnosis was mature teratoma, including all three germ layers. A carcinoid tumor was evident among teratoid tissues and it was thought to be a teratoma with malignant transformation. The patient did not have a carcinoid syndrome and had an uneventful recovery. She has been followed for 31 months with no recurrence. Carcinoid tumors rarely occur in teratomas of the ovary and the testis and, to our knowledge, this is the first case of carcinoid arising in a retroperitoneal mature teratoma.

Carcinoid Tumor↗