Stephen R. Watt-Smith

Comparison of arthrotomographic and magnetic resonance images of 50 temporomandibular joints with operative findings.

Arthrotomography and magnetic resonance imaging (MRI) were carried out on 50 temporomandibular joints (TMJs) in 48 patients who were being considered for surgery for clinically diagnosed internal derangement. The patients presented over a 4-year period with pain and dysfunction which had failed to respond to conservative management. Open surgery was carried out on all TMJs and operative findings compared with the results of imaging. The clinical diagnosis of internal derangement was confirmed in every case by imaging and at surgery. Arthrotomography over-diagnosed non-reducibility of an anteriorly displaced meniscus and perforation. MRI over-diagnosed non-reducibility to a lesser extent and under-diagnosed perforation. MRI demonstrated neither bony changes nor adhesions. Dynamic arthrotomography produced the best images of meniscal derangement in function and the pre-arthrogram tomograms were the best indicator of osseous abnormality. Arthrotomography was the preferred imaging technique.

Power spectral analysis of the effects of epinephrine, norepinephrine, dobutamine and dopexamine on microcirculation following free tissue transfer

Background: The use of pressor drugs after microsurgical free tissue transfer remains controversial because of potential vasoconstrictor effects on the free flap. Noninvasive monitoring of free flaps with laser Doppler flowmetry may provide further information regarding the local regulation of blood flow in the flap tissues during pressor infusions. This study evaluated the effects of four commonly used pressor agents. Methods: Twenty four patients (25 data sets) undergoing head and neck cancer resection and free flap reconstruction were recruited. Epinephrine, norepinephrine, dopexamine, and dobutamine were infused in a random order at four infusion rates, after surgery, with free flap and control area (deltoid region) laser Doppler skin blood flow monitoring. Frequency analysis of the Doppler waveform was performed utilizing the time period immediately before the first drug infusion for each patient as baseline. Results: At baseline there was less power at the 0.002–0.6 Hz frequency in the flap compared with control tissue consistent with surgical denervation. At maximum epinephrine infusion rates, the control of blood flow moved toward (i.e., proportion of power increased in) the lower frequencies, as smooth muscle mediated (myogenic) control began to dominate blood flow, an effect most marked with norepinephrine. Dobutamine and dopexamine had little effect on control of blood flow. Conclusions: Denervation of free flap tissue is demonstrable using spectral analysis of laser Doppler blood flow signals. With norepinephrine the control of blood flow shifts toward low frequency vasomotion where blood flow depends mostly on average blood pressure, making it potentially the most suitable agent following free tissue transfer.

Alveolar soft-part sarcoma of the tongue: report of a case and review of the literature

Alveolar soft part sarcoma (ASPS) accounts for less than 1% of all sarcomas. More frequently encountered within the lower limbs, the authors present a 24-year-old male with ASPS presenting as an asymptomatic swelling of the lateral tongue. At 12 months post wide local excision of the lesion, the patient remains well with no evidence of local or regional recurrence. Histological and immunohistochemical features are diagnostic of ASPS. Whilst rare, head and neck surgeons should be aware of ASPS as a potential cause of slow growing lesions, as early surgical resection is vital in view of the propensity for metastatic spread.

Cross-sectional imaging of a cadaveric human heart

The precise relationship of the components of the heart can be difficult to understand. With recent developments in cardiac ultrasound and other imaging modalities, most professionals need to be familiar with cross‐sectional cardiac anatomy. We have created a teaching technique based on a normal human heart removed at autopsy. It was scanned using a computed tomography scanner and the images examined in different planes. The images were annotated and used in a computer‐based teaching program to convey the details of cardiac anatomy. Images corresponding to planes typically used in echocardiography were also examined. The resulting images were of high resolution and illustrated many subtle structures rarely seen in conventional studies of cardiac anatomy. This system has benefits to both clinicians and anatomists. Clin. Anat. 11:75–80, 1998.

Automatic upstaging of tongue squamous cell carcinoma with lateral extrinsic muscle involvement is not justified

The TNM classification for oral malignancies has been criticized for its upstaging to T4a when tumour involves styloglossus, hyoglossus, palatoglossus and genioglossus. The aims of this study were to (1) create an anatomical computer atlas of extrinsic tongue musculature, and (2) reassess the original staging of pre-treatment archived magnetic resonance images (MRI) of tongue carcinomas using the strict extrinsic muscle criteria. The anatomy of the extrinsic tongue muscles was mapped using images from the Visible Human Project (VHP) to create a computer model of the extrinsic tongue muscles. This was co-registered with 87 archived pre-staging MRI scans of tongue carcinomas to assess tumour ingress of the extrinsic tongue muscles. Of the 87 image sets reviewed, 16 were of superficial tumours not visible on MRI. In the remaining 71 cases that showed positive extrinsic muscle tumour ingress, 52% were upstaged from T1/2/3 tumours to cT4a based upon this finding. Extrinsic lateral and genioglossus muscle invasion did not predict occult cervical lymph node invasion or disease-related survival. In conclusion, tumour invasion of styloglossus or hyoglossus would result in the majority of lateral tongue tumours being staged T4a. Such stratification is of little clinical relevance, and an alternative more reliable method is required.

The nasolabial approach: a potential alternative to the lip-splitting incision for maxillectomy

First described by Weber and later modified by Fergusson, the Weber-Fergusson incision has undergone numerous modifications, but the fundamental approach to maxillectomy has largely remained the same. We report the potential benefit of a nasolabial incision for partial maxillectomy. The incision is hidden within the nasolabial fold and obviates the need for division of the upper lip, which may undergo atrophy and shortening after radiotherapy.

Polycystic Parotid Disease in a Male Child: Report of a Case and Review of the Literature

Non-neoplastic cysts account for approximately 6% of all lesions causing salivary gland enlargement. Polycystic parotid disease (PPD) is a rare cause of parotid gland swelling, with only 10 investigating groups identified within the literature accounting for 13 reported cases. The clinical features of PPD were first reported by Mihalyka in 1962, but it was not until 981 that Seifert and Donath provided histologic confirmation and the condition termed bilateral dysgenetic polycystic parotid glands. We present the second reported male case of PPD presenting to the Department of Oral and Maxillofacial Surgery, Oxford Radcliffe Hospitals NHS Trust (Oxford, UK).

Ewings sarcoma of the zygoma reconstructed with a gold prosthesis: a rare tumor and unique reconstruction.

INTRODUCTION Ewings sarcoma (ES) is a rare tumor, most commonly encountered within the long bones during the first 20 years of life. CASE REPORT We report the sixth case of ES of the zygoma, occurring in a 31-year-old male, and presenting a unique reconstructive opportunity. Diagnosis and preoperative planning were aided by CT/MR coregistration. Surgical reconstruction using 3D reconstructed CT images to produce an anatomically correct model provided the basis for a gold prosthesis construction. DISCUSSION Delayed definitive reconstruction provided opportunity for adequate tumor recurrence surveillance, and definitive histological diagnosis. The artefact produced on MR imaging from gold implants is minimal, permitting the unrestricted identification of potential future recurrence. CONCLUSION This case highlights the benefits of coregistration of radiological imaging, and custom-made gold prostheses providing the advantage of artefact-free MR imaging, which should be considered in patients requiring resection of zygomatic tumors and subsequent reconstruction.

Three-dimensional Reconstruction of the Craniofacial Skeleton With Gradient Echo Magnetic Resonance Imaging ("black Bone"): What Is Currently Possible?

Abstract Three-dimensional (3D) reconstructed computed tomography (CT) imaging has become an integral component of craniomaxillofacial patient care. However, with increasing concern regarding the use of ionizing radiation, particularly in children with benign conditions who require repeated examinations, dose reduction and nonionizing alternatives are actively being sought. The “Black Bone” magnetic resonance imaging (MRI) technique provides uniform contrast of the soft tissues to enhance the definition of cortical bone. The aim of this study was to develop methods of 3D rendering of the craniofacial skeleton and to ascertain their accuracy. “Black Bone” MRI datasets acquired from phantoms, adult volunteers and patients were segmented and surface and/or volume rendered using 4 commercially available or open source software packages. Accuracy was explored using a custom phantom (permitting direct measurement), CT and MRI. “Black Bone” MRI datasets were successfully used to create 3D rendered images of the craniofacial skeleton in all 4 software packages. Comparable accuracy was achieved between CT and MRI 3D rendered images of the phantom. The “Black Bone” MRI technique provides a viable 3D alternative to CT examination when imaging the craniofacial skeleton.

Giant Cell Granuloma With Aneurysmal Bone Cyst Change Within the Mandible During Pregnancy: A Management Dilemma

Central giant cell granuloma (CGCG) is a benign osteolytic lesion typically arising within the mandible or maxilla. CGCG has an annual incidence of 1.1 per 1 illion persons, and it accounts for 7% of all benign umors affecting the mandible. CGCG has a propenity to develop in young female patients, with 60% of ases occurring in patients who are under 30 years of ge. Rapid growth has been reported to occur during pregnancy, suggesting that these tumors may be under hormonal control. Studies to date have only dentified estrogen receptors in peripheral giant cell ranulomas of the gingiva, and no progesterone reeptors have yet been identified. CGCGs are typically asymptomatic, with diagnosis resulting from an incidental finding on imaging. Radiologically, CGCG may mimic a variety of mandibular pathologies, including cysts, odontogenic tumors, fibroosseous lesions, vascular malformations, and malignant disease. Surgical management largely remains the