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PubMed2004

Hyaluronidase allergy after peribulbar anesthesia with orbital inflammation.

A 70-year-old woman previously exposed to hyaluronidase during ophthalmic surgery had excision of hypertrophic bulbar conjunctival tissue in the right eye. Hyaluronidase was added to the peribulbar anesthetic agent. Five days postoperatively, the patient presented with proptosis in the right eye, extraocular muscle restriction, and decreased visual acuity. She was apyrexial with a normal white cell count; computed tomography of the orbits showed a diffuse increase in soft tissue density. Clinical features were unchanged after 24 hours of intravenous antibiotics, but subsequent administration of high-dose oral steroids led to clinical improvement.

Aged↗

PubMed2004

Olfactory system activation from sniffing: effects in piriform and orbitofrontal cortex.

Neuroimaging studies suggest that piriform cortex is activated at least in part by sniffing. We used H(2)(15)O positron emission tomography (PET) to study 15 healthy volunteers while they participated in four conditions, two of which were sniffing odorants and odorless air. The remaining two conditions involved a constant, very low flow of either odorized or odorless air during velopharyngeal closure (VPC), a technique that prevents subject-induced airflow through the nasal passages. Contrary to expectation, sniffing under odorless conditions did not induce significant piriform and surrounding cortical (PC+) activity when compared to odorless VPC, even at a liberal statistical threshold. However, a small correlation emerged in PC+ between the difference signal of [odorless sniffing - odorless VPC] and peak rate of nasal pressure change. PC+ activity was, however, strongly evoked by odorant exposure during sniffing and VPC, with neither technique showing greater activation. Activity in orbitofrontal (olfactory association) cortex was absent during odorant stimulation (OS) with VPC, but present during odorant sniffing. Sniffing may therefore play an important role in facilitating the higher-order analysis of odors. A right orbitofrontal region was also activated with odorless sniffing, which suggests a possible orbitofrontal role in guided olfactory exploration.

Adult↗

PubMed1999

Simulation studies of optimum energies for DXA: dependence on tissue type, patient size and dose model.

Dual-energy x-ray absorptiometry (DXA) is a well established technique for measuring bone mineral density (BMD). However, in recent years DXA is increasingly being used to measure body composition in terms of fat and fat-free mass. DXA scanners must also determine the soft tissue baseline value from soft-tissue-only regions adjacent to bone. The aim of this work is to determine, using computer simulations, the optimum x-ray energies for: a number of dose models, different tissues, i.e. bone mineral, average soft tissue, lean soft tissue and fat; and a range of anatomical sites and patient sizes. Three models for patient dose were evaluated: total beam energy, entrance exposure and absorbed dose calculated by Monte Carlo modelling. A range of tissue compositions and thicknesses were chosen to cover typical patient variations for the three sites: femoral neck, PA spine and lateral spine. In this work, the optimisation of the energies is based on: (1) the uncertainty that arises from the quantum statistical nature of the number of x-rays recorded by the detector, and (2) the radiation dose received by the patient. This study has deliberately not considered other parameters such as detector response, electronic noise, x-ray tube heat load etc, because these are technology dependent parameters, not ones that are inherent to the measuring technique. Optimisation of the energies is achieved by minimisation of the product of variance of density measurement and dose which is independent of the absolute intensities of the x-ray beams. The results obtained indicate that if solving for bone density, then Elow in the range 34 to 42 keV, Ehigh in the range 100 to 200 keV and incident intensity ratio (low energy/high energy) in the range 3 to 10 is a reasonable compromise for the normal range of patient sizes. The choice of energies is complicated by the fact that the DXA unit must also solve for fat and lean soft tissue in soft-tissue-only regions adjacent to the bone. In this case the ranges of energies suggested above are acceptable only for the average phantom. In extreme cases the variance-dose product can be up to 50 times higher than for the ideal energies.

Absorptiometry, Photon↗

PubMed1988

Radiographical documentation of direct injury of the intracanalicular segment of the optic nerve in the orbital apex syndrome.

In the radiographical evaluation of the orbital apex syndrome, standard radiographs, tomograms, and computed tomographic scans have proved useful in the demonstration of the bony pathology, especially for optic canal fractures. The limitation of these methods, however, remains in their inability to provide accurate delineation of the associated soft tissue pathology, including the presence of optic nerve sheath hematoma. Recent developments in computer technology and graphic imaging are now available to provide an accurate three-dimensional radiographical analysis of the extent of skeletal and soft tissue injury in the orbital apex syndrome. The physician, in essence, can perform a radiographical "living autopsy". The technique was used to evaluate a patient with bilateral apex syndrome. It clearly showed that a severe direct injury to the intracanalicular portion of the optic nerve was responsible for the development of blindness in this patient. The progression of optic nerve injury, from perineural sheath hematoma to the ultimate development of optic nerve atrophy and fibrosis, was radiographically documented.

Adult↗

PubMed1999

Positron emission tomography with 18fluorine-labelled deoxyglucose: utility in localized and advanced prostate cancer.

OBJECTIVE: To determine the role of the positron emission tomography (PET) with 18F-labelled deoxyglucose in the identification of prostatic cancer in the iliac and obturator lymphatic nodes before radical prostatectomy, and in the localization of relapse in patients in biochemical progression. PATIENTS AND METHODS: Twenty-one patients were divided into two groups. Group A consisted of 11 men diagnosed with organ-confined prostate cancer, where attention was focused on the iliac and obturator lymphatic nodes, the results being compared with the pathological anatomy obtained from surgical procedures. Group B included 10 patients treated by radical prostatectomy, radiotherapy or orchidectomy and who were in biochemical progression, in whom the aim was to identify recurrence of the disease. RESULTS: In none of the 11 patients of group A who had undergone radical prostatectomy were deposits of radiotracer identified in the area of the iliac and obturator nodes which would indicate node metastases. However, the histopathological analysis of these nodes showed tumour in three patients. In group B the PET scans showed recurrence of prostate cancer (by deposits of radiotracer) more clearly than did computed tomography (CT) in two patients (both with recurrence in soft tissue). In one patient bone scintigraphy identified a lesion compatible with prostatic disease in the bone; this was clinically confirmed but was not identified by PET. CONCLUSION: PET, using deoxyglucose labelled with 18F, cannot reliably identify prostatic adenocarcinoma in the iliac and obturator lymph nodes before surgery; other tracers may give better results. To locate relapses in patients with biochemical progression, PET seems to have better sensitivity than CT when identifying diseases in soft tissues and is possibly inferior to bone scintigraphy in detecting bony metastases.

Adenocarcinoma↗

PubMed1996

Computed tomographic analysis of airway dimensions after carotid endarterectomy.

Airway obstruction is a rare but serious postoperative complication of carotid endarterectomy. We prospectively studied airway dimensions between the hyoid bone and cricoid cartilage in patients undergoing carotid endarterectomy using preoperative and postoperative computed tomographic (CT) scans of the neck. CT scans showed soft tissue swelling in all 19 patients. Five patients with clinical evidence of airway obstruction and a hematoma present on CT scan were intubated postoperatively. The three-dimensional reconstruction of the neck from the CT scans showed a reduction in the volume of the airway in all patients. This reduction was greater in the intubated (62% +/- 9%) compared to the nonintubated (32% +/- 7%) patients (P < 0.01). The anterior-posterior and transverse diameters of the airway were reduced, while retropharyngeal edema was increased after carotid endarterectomy. This change was greater for the upper airway at the level of the hyoid compared to the arytenoids and cricoid, and was significantly greater in the intubated than the nonintubated patients. Tracheal deviation was greater in the intubated than in the nonintubated patients. These results demonstrate significant soft tissue edema of the neck after carotid endarterectomy that reduces airway volume and can result in airway obstruction.

Aged↗

PubMed1999

[The extracapsular spread of cervical lymph node metastases: the diagnostic value of computed tomography].

OBJECTIVE: To assess the value of computed tomography in the determination of extracapsular neoplastic spread and soft tissue infiltration of cervical lymph nodes. MATERIALS AND METHODS: Prospectively 165 CT reports of patients with squamous cell carcinoma in the head-neck region were compared with the histologic specimens after neck dissection. RESULTS: CT reached a sensitivity of 80.9% in the determination of extra-capsular neoplastic spread. The infiltration of cervical muscles and the jugular vein was always determined but-often diagnosed false-positive. Therefore, the overall specificity in determining extracapsular neoplastic spread was low with 72.7%. CONCLUSIONS: The accuracy of computed tomography (76.3%) in the determination of extracapsular neoplastic spread, infiltration of cervical muscles and the jugular vein is only partially satisfying.

Carcinoma, Squamous Cell↗

PubMed1999

Extraskeletal osteochondroma of the foot.

A case of pathologically proven extraskeletal osteochondroma is presented with magnetic resonance imaging (MRI), computed tomography (CT), bone scan and radiographic findings. The diagnosis of extraskeletal osteochondroma should be considered when a discrete, ossified mass is localized in the soft tissues of the distal extremities. Nomenclature surrounding this entity is controversial and is discussed.

Adolescent↗

PubMed1997

CT and MRI evaluation of musculoskeletal infection.

While the plain film and nuclear medicine bone scan are still the traditional imaging modalities used in the evaluation of musculoskeletal infection, the cross-sectional imaging modalities, computed tomography (CT) and magnetic resonance imaging (MRI), have become critical in the delineation of many types of musculoskeletal infection. In particular, the evaluation of soft tissue infections, including cellulitus, myositis, fasciitis, abscess, and septic arthritis are often best evaluated by MRI or CT due to their excellent anatomic resolution and soft tissue contrast. Even in osseous infection, CT and MRI can give better anatomic delineation of the extent of infection. In cases where the plain film and nuclear medicine bone scan findings are complicated due to previous surgery, trauma, or underlying illness, the anatomic resolution and soft tissue contrast provided by MRI and CT are often necessary to determine if underlying infection exists. MRI's visualization of the bone marrow allows for the sensitive detection of osteomyelitis, although specificity for the diagnosis of osteomyelitis is aided by other findings, including cortical destruction. The CT and MRI findings in the spectrum of musculoskeletal infections are discussed and contrasted, and pitfalls in their evaluation of musculoskeletal infection are described.

Abscess↗

PubMed2000

MRI-guided celiac plexus block.

Celiac plexus block is used as a palliative procedure in cases of severe upper abdominal pain caused by pancreatitis or tumors of the pancreas. It can be guided by bony landmarks, fluoroscopy, ultrasound (US), or computed tomography (CT). To avoid severe complications, methods visualizing soft tissue, like CT and magnetic resonance (MR) imaging, are preferable. We describe celiac plexus blocks carried out in an open MR scanner, offering needle guidance with an optical tracking system and near real-time image acquisition. Eight patients with severe chronic abdominal pain were included. In these, 14 celiac blocks were carried out. Good or total pain relief was achieved in 8 of the 14 blocks (57%), a moderate effect in 5 blocks (36%), and no effect in 1 block (7%). The placement of the needle was easily guided with MR in all cases. The MR technique ensures good visualization of soft tissue, direct monitoring of needle movement and avoids exposure to ionizing radiation. Celiac plexus block can safely be carried out in an open MR scanner.

Abdominal Pain↗

PubMed2006

Capturing cases in workers' compensation databases: the example of neck pain.

BACKGROUND: There is a need to more accurately enumerate workers with musculoskeletal injuries who make lost-time claims to workers compensation boards. The objective of this study is to develop an approach to more accurately enumerate these workers. METHODS: Lost-time claims to the Ontario Workplace Safety & Insurance Board (WSIB) were reviewed. Using neck pain as an example, nature of injury and part of body codes were identified to classify cases. Claims of a random sample of 434 claimants were reviewed. The proportion of claimants classified as having neck pain was computed. RESULTS: The proportion of claimants classified with soft-tissue injuries to the neck varied from 0.88 for codes including "neck/cervical region," 0.69 for "back region" to 0.05 for those coded as "shoulder/upper arm." CONCLUSIONS: Restricting the enumeration of injuries to specific part of body codes can lead to a gross underestimation of the magnitude of soft-tissue disorders in epidemiological studies using workers' compensation data. The proposed approach leads to more accurate enumeration.

Accidents, Occupational↗

PubMed1999

Ossifying intramuscular metastasis from colon cancer: report of a case.

PURPOSE: This report presents a patient who developed severe buttock pain because of an ossified intramuscular metastasis from a sigmoid colon cancer. METHODS: This is a case report and review of the literature for intramuscular metastasis from colon cancer. RESULTS: Computed tomography and magnetic resonance imaging showed a soft-tissue mass with heavy calcification. Histologically, mature compact bone was observed with adenocarcinoma cells dispersed among the bony trabeculae. CONCLUSION: When an intramuscular mass is seen, even if it contains extensive calcification, metastasis from colon cancer should be included in differential diagnosis.

Adenocarcinoma↗

PubMed1989

[Documentation of surgical data with dBASE-III].

By the development of microelectronic it is nowadays possible to manage even large amounts of data by personal computers (PC). Quality control and a prescribed operationstatistics compels to use a computer. In most cases, however, the employment of a computer fails because of the lack of adequate soft-ware. As a basis of such a use the relational data bank system dBASE-III offers it's services. The introduced system OPSTAT serves to fill in and to control the operation manual and makes it possible to register and to analyse all operations, diagnoses, complications and special risk factors.

Documentation↗

PubMed2006

Axial loading with hyperflexion injury to the atlas resulting in crushed lateral masses.

A 40-year-old man was involved in an ATV accident, in which he landed on the top of his head. There was no neurological deficit. A plain radiograph showed prevertebral soft tissue swelling at the atlas and axis level. Computed tomography (CT) demonstrated vertical fractures of the anterior aspects of both lateral masses of the atlas, extending to the junction of the lateral mass with the anterior arch bilaterally. There was no lateral offset of the lateral masses. The mechanism of injury is believed to be axial loading along with hyperflexion.

Accidents↗

PubMed1982

Postpharyngeal lymphoid tissue in Angle Class I and Class II malocclusions.

Opinions differ with regard to the relationship of adenoids and type of malocclusion. To study this possible relationship, xeroradiographic lateral cephalograms were made of eighty Class I (Angle) and sixty-four Class II, Division 1 (Angle) malocclusions to obtain reliable measures of the epipharyngeal lymphoid tissue, the nasopharyngeal airway, the nasopharynx, and certain cephalometric landmarks. Xeroradiographic cephalograms provide superior visualization with edge-enhancement effect for both soft and hard tissues. Electronic digitization and a comprehensive computer analysis were used to assess the head films. Significant differences were found for some of the linear and angular cephalometric criteria between the two malocclusion categories. A sexual dimorphism was observed. These skeletal and dental differences were anticipated in this mixed malocclusion sample, as prior cephalometric studies which compare different classes of malocclusion have shown. Airway space did not appear to vary with the type of malocclusion. Some low-level correlations were found between the size of the nasopharyngeal area and certain skeletal characteristics. These correlations depended on both the malocclusion type and the sex of the individual. The lateral, two-dimensional cephalogram does not seem to offer satisfactory information relating the nasopharyngeal area to Class I or to Class II, Division 1 malocclusions.

Cephalometry↗

PubMedDate not supplied

Carcinoid tumor of the middle ear: a case report.

Middle ear (ME) carcinoid tumor is exceedingly rare. We present a case of ME carcinoid tumor in a 29-year-old woman whose chief complaints were right otalgia, aural fullness, hearing loss, and facial palsy of 5 days duration. A reddish bulging mass behind the right eardrum and right facial palsy staged as grade IV on the House-Brackmann scale were noted. The high-resolution computed tomography of the temporal bone showed a soft-tissue density mass in the right middle ear and antrum without bony invasion. Although the initial diagnosis was ME adenoma made by the intraoperative frozen section report, the tumor was resected completely by a modified conservative ossicles-preservation method. The patient's initial symptoms of otalgia, aural fullness, and hearing loss immediately improved after surgery, and facial palsy diminished in the following months. No recurrence was noted after 12 months of follow-up.

Adult↗

PubMedDate not supplied

Delayed severe airway obstruction due to hematoma following stellate ganglion block.

BACKGROUND AND OBJECTIVES: Delayed onset of airway obstruction following stellate ganglion block (SGB) may be life threatening. We treated a patient who developed a severe airway obstruction caused by a large hematoma several hours after an SGB. METHODS: A 62-year-old woman suffering from sudden deafness developed dyspnea 2 hours after undergoing her fourth SGB, and evidenced swelling and tenderness in her anterior neck and chest. Her pharyngolaryngeal tissues were edematous, and the glottis was markedly narrowed. Computed tomograms and magnetic resonance images revealed a large soft tissue mass extending from the first cervical vertebra to the diaphragm. RESULTS: Surgical tracheotomy was performed to maintain her airway. Swelling of the vocal cord disappeared on the eleventh day after the operation. CONCLUSIONS: We believe that the SGB needle injured the vertebral artery and caused massive hemorrhage anterior to the cervical vertebra, subsequently inducing pharyngolaryngeal edema by obstructing the venous and lymphatic drainage of the cervical region.

Airway Obstruction↗

PubMed2000

Standardization of the 24-hour diet recall calibration method used in the european prospective investigation into cancer and nutrition (EPIC): general concepts and preliminary results.

OBJECTIVES: Despite increasing interest in the concept of calibration in dietary surveys, there is still little experience in the use and standardization of a common reference dietary method, especially in international studies. In this paper, we present the general theoretical framework and the approaches developed to standardize the computer-assisted 24 h diet recall method (EPIC-SOFT) used to collect about 37 000 24-h dietary recall measurements (24-HDR) from the 10 countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). In addition, an analysis of variance was performed to examine the level of standardization of EPIC-SOFT across the 90 interviewers involved in the study. METHODS: The analysis of variance used a random effects model in which mean energy intake per interviewer was used as the dependent variable, while age, body mass index (BMI), energy requirement, week day, season, special diet, special day, physical activity and the EPIC-SOFT version were used as independent variables. The analysis was performed separately for men and women. RESULTS: The results show no statistical difference between interviewers in all countries for men and five out of eight countries for women, after adjustment for physical activity and the EPIC-SOFT program version used, and the exclusion of one interviewer in Germany (for men), and one in Denmark (for women). These results showed an interviewer effect in certain countries and a significant difference between gender, suggesting an underlying respondent's effect due to the higher under-reporting among women that was consistently observed in EPIC. However, the actual difference between interviewer and country mean energy intakes is about 10%. Furthermore, no statistical differences in mean energy intakes were observed across centres from the same country, except in Italy and Germany for men, and France and Spain for women, where the populations were recruited from areas scattered throughout the countries. CONCLUSION: Despite these encouraging results and the efforts to standardize the 24-HDR interview method, conscious or unconscious behaviour of respondents and/or interviewer bias cannot be prevented entirely. Further evaluation of the reliability of EPIC-SOFT measurements will be conducted through validation against independent biological markers (nitrogen, potassium).

Analysis of Variance↗