Unilateral Warthin's tumour in a patient of Afro-Caribbean descent.

Warthin's tumours are the second most common benign tumours of the parotid gland. The authors report the case of a 40-year-old man of Afro-Caribbean decent who presented with a painless mass at the angle of the right mandible. It was an incidental finding while shaving and was not associated with any symptoms. Arrangements were made for him to undergo an ear, nose and throat (ENT) evaluation. Axial contrast-enhanced CT of head and neck region revealed a well-defined cystic lesion. Fine-needle aspiration cytology was inconclusive. Right superficial partial parotidectomy was performed to remove the lesion. Histological examination confirmed a diagnosis of a Warthin's tumour.

Erratum: Primary gastric Hodgkin's lymphoma: favourable outcome following multi-agent chemotherapy without surgical intervention.

[This corrects the article DOI: 10.1136/bcr.11.2010.3476.].

Erratum: Profound and persistent painful paclitaxel peripheral neuropathy in a premenopausal patient.

[This corrects the article DOI: 10.1136/bcr.12.2010.3645.].

Wall shear stresses remain elevated in mature arteriovenous fistulas: a case study.

Maintaining vascular access (VA) patency continues to be the greatest challenge for dialysis patients. VA dysfunction, primarily due to venous neointimal hyperplasia development and stenotic lesion formation, is mainly attributed to complex hemodynamics within the arteriovenous fistula (AVF). The effect of VA creation and the subsequent geometrical remodeling on the hemodynamics and shear forces within a mature patient-specific AVF is investigated. A 3D reconstructed geometry of a healthy vein and a fully mature patient-specific AVF was developed from a series of 2D magnetic resonance image scans. A previously validated thresholding technique for region segmentation and lumen cross section contour creation was conducted in MIMICS 10.01, allowing for the creation of a 3D reconstructed geometry. The healthy vein and AVF computational models were built, subdivided, and meshed in GAMBIT 2.3. The computational fluid dynamic (CFD) code FLUENT 6.3.2 (Fluent Inc., Lebanon, NH) was employed as the finite volume solver to determine the hemodynamics and shear forces within the healthy vein and patient-specific AVF. Geometrical alterations were evaluated and a CFD analysis was conducted. Substantial geometrical remodeling was observed, following VA creation with an increase in cross-sectional area, out of plane curvature (maximum angle of curvature in AVF=30 deg), and angle of blood flow entry. The mean flow velocity entering the vein of the AVF is dramatically increased. These factors result in complex three-dimensional hemodynamics within VA junction (VAJ) and efferent vein of the AVF. Complex flow patterns were observed and the maximum and mean wall shear stress (WSS) magnitudes are significantly elevated. Flow reversal was found within the VAJ and efferent vein. Extensive geometrical remodeling during AVF maturation does not restore physiological hemodynamics to the VAJ and venous conduit of the AVF, and high WSS and WSS gradients, and flow reversal persist. It is theorized that the vessel remodelling and the continued non-physiological hemodynamics within the AVF compound to result in stenotic lesion development.

Profound and persistent painful paclitaxel peripheral neuropathy in a premenopausal patient.

The authors herein report the case of a 35-year-old woman undergoing adjuvant therapy for node positive breast cancer, who presented with short and rapidly progressive history of bilateral lower limb symptoms of peripheral neuropathy following therapy with paclitaxel. MRI of her neural axis revealed no leptomeningeal enhancement or focal metastatic lesions. Neurophysiological tests favoured toxic sensory axonal polyneuropathy. She remains symptomatic following discontinuation of therapy 20 months ago, and is under review with pain management.

Primary gastric Hodgkin's lymphoma: favourable outcome following multi-agent chemotherapy without surgical intervention.

The authors report the case of a 51-year-old man who presented with left-sided abdominal pain and weight loss associated with drenching night sweats. Preliminary blood tests yielded no specific cause for his symptoms, but abdominal ultrasound revealed multiple hepatic lesions and peripancreatic lymphadenopathy. Further imaging, including positron emission tomography (PET)/CT, revealed fludeoxyglucose 18F (FDG) avid uptake within lymphadenopathy above and below the diaphragm and also noted gastric thickening. Diagnosis was established with gastric biopsy and revealed gastric Hodgkin's lymphoma. He was started on and tolerated multi-agent chemotherapy. Repeated PET/CT and gastric biopsy showed complete metabolic and pathologic response to treatment.

Alopecia universalis, hypothyroidism and pituitary hyperplasia: polyglandular autoimmune syndrome III in a patient in remission from treated Hodgkin lymphoma.

We herein report a case of a 33-year-old man in remission from Hodgkin lymphoma, who presented with reduced potency and hair loss. Initial endocrine tests revealed autoimmune hypothyroidism. An MRI of his pituitary gland at onset revealed hyperplasia. He tolerated replacement endocrine therapy with good response, but with no improvement in his alopecia universalis. A repeat MRI, 6 months after his initial endocrine manipulation, showed resolution of his pituitary hyperplasia.

Improved assessment and treatment of abdominal aortic aneurysms: the use of 3D reconstructions as a surgical guidance tool in endovascular repair.

BACKGROUND: Endovascular repair is fast becoming the treatment of choice for abdominal aortic aneurysms in anatomically suitable patients. 3D reconstructions not only aid conventional 2D measurements but also allow further analyses of the vessel anatomy. METHODS: Computed tomography scan data for four male patients awaiting endovascular repair were obtained. 3D reconstructions were performed to determine measurements. Wall stress was determined on one particular case using finite element analysis. RESULTS: 3D reconstruction allows measurements to be obtained that can be difficult to determine using 2D images. This method complements traditional 2D approaches. Reconstructions also provided imaging of potential anatomical problems. Wall stress results showed key regions that may be possible rupture sites. CONCLUSION: 3D reconstructions greatly aid surgical planning. As stent-graft devices evolve, anatomical difficulties previously considered contraindications to endovascular repair can now be overcome with careful planning. 3D reconstruction is a useful adjunct to assessment and planning of endovascular repair.

Correlation of serum CA125 with stage, grade and survival of patients with epithelial ovarian cancer at a single centre.

To evaluate the relationship between serum CA125 tumour marker level before and after surgery of epithelial ovarian carcinoma and assess its potential role as a prognostic factor. A retrospective review of 87 patients with epithelial ovarian carcinoma at a single centre between January 2001 and December 2005 was performed. Serum CA125 levels were assessed for their relationship to pathological stage, tumour grade, tumour volume and age as well as overall survival. A total of 75 patients, mean age 58.94 years and median follow-up of 24 months were included in the analysis. While the preoperative CA125 level did not correlate significantly with stage, tumour grade or survival, the postoperative CA125 correlated to FIGO stage (p<0.0001), tumour grade (p<0.0001) and overall survival (p=0.01). Reduced survival was noted with increasing age at the time of surgery (p=0.009) and bulk of the residual disease postoperatively (p=0.011).

Use of finite element analysis in presurgical planning: treatment of mandibular fractures.

BACKGROUND: The current clinical procedure for mandible fracture fixation is plate application. 3D reconstructions are used to validate procedures numerically preceding experimental analysis. This study outlines the methods used to reconstruct a numerical model of the mandible. METHODS: A CT scan from a 22-year-old male patient with a healthy unfractured mandible was obtained. A 3D reconstruction was carried out using Mimics via thresholding and segmentation techniques. Boundary conditions and muscle forces were applied, and simulations were performed using ABAQUS. RESULTS: 3D reconstruction allows for precise anatomical dimensions, which can be used for further engineering analysis. Using the surgical Champy technique as an example, results showed that the mandible model returned to normal function post-plating. CONCLUSIONS: The study shows the clinical relevance of 3D reconstructions to plan surgical procedures. Results illustrate the benefit of carrying out numerical validations as a prerequisite to experimental modelling and as a method of pre-validating surgical procedures.

Isolated hypoglossal nerve palsy: a harbinger of malignancy.

The hypoglossal nerve is an underrated nerve usually consigned to a few words in anatomical text books, under the last four cranial nerves. However, paralysis of this nerve may be the first indication of a serious underlying disorder. Excluding previous surgery, radiotherapy and trauma, 50 per cent of cases of isolated hypoglossal nerve palsy are idiopathic. A further 20 per cent are malignant, 20 per cent are vascular and 10 per cent are due to miscellaneous causes. Presentation of an isolated hypoglossal nerve palsy is therefore an ominous sign. There is confusion over both cause and investigation, and management protocols for isolated hypoglossal nerve palsy are ill-defined. We present a case of isolated hypoglossal palsy which was due to a metastatic skull base deposit. This case illustrates the fact that magnetic resonance imaging is the investigation of choice in assessing the entire course of the hypoglossal nerve.

Does size matter? The impact of calf muscle volume on venous return in patients with venous leg ulcers.

OBJECTIVES: The calf muscle pump is recognized as an integral component of effective venous return from the lower limbs. The aim of this study was to determine if there is a correlation between calf muscle volume and venous blood flow among patients with venous leg ulcers. METHODS: Nine patients with venous leg ulceration were recruited for this study. These patients underwent haemodynamic testing using duplex ultrasound to measure peak venous velocities in response to voluntary maximum plantar flexion, with and without compression bandaging. Each patient then had magnetic resonance imaging (MRI) of the lower limbs. Calf muscle volume was calculated from the MRI images using a specially designed Matlab computer program to identify and count muscle pixels. Analyses applied Pearson's correlation coefficient to determine correlation between calf muscle volume and mean peak venous velocities in response to voluntary contraction. RESULTS: No correlation was seen between calf muscle volume and haemodynamic venous return in response to voluntary contraction, with or without compression bandaging. CONCLUSION: The volume of calf muscle available for promoting venous return alone may not be an accurate indicator of muscle functioning capability.

Vacuum ultraviolet postionization of aromatic groups covalently bound to peptides.

Experiments demonstrate that peptides with ionization potentials (IPs) above 7.87 eV can be single-photon-ionized in the gas phase with a molecular fluorine laser following prior chemical derivatization with one of several aromatic tags acting as chromophores. 4-(Dimethylamino)benzoic acid, 1-naphthylacetic acid, and 9-anthracenecarboxylic acid (denoted Benz, Naph and Anth, respectively) behave as chromophores, allowing single-photon ionization for vacuum ultraviolet (VUV) laser light by lowering the IP of the tagged peptide. Anth-tagged peptides that are laser-desorbed from a substrate and subsequently postionized produce mass spectra dominated by the intact radical cation, although protonated ions and fragmented species are also observed. Electronic structure calculations on Anth-tagged peptides indicate that in addition to lowering the ionization potential, the presence of the aromatic tag increases charge localization on and delocalization across the ring structure, which presumably stabilizes the radical cation. Measurements on several tagged peptides confirm this calculation and show that the stabilizing effect of the tag increases with the size of the conjugated system in the order Benz < Naph < Anth. The tagged hexapeptide Anth-GAPKSC exhibits the parent ion, whereas the Benz- and Naph-tagged peptides do not. These results are supported by the experimental comparison of Anth-tagged vs untagged tryptophan, further suggesting that VUV postionization of tagged high-IP species is a promising method for expanding the capabilities of mass spectrometric analyses of molecular species.

3-D numerical simulation of blood flow through models of the human aorta.

A Spiral Computerized Tomography (CT) scan of the aorta were obtained from a single subject and three model variations were examined. Computational fluid dynamics modeling of all three models showed variations in the velocity contours along the aortic arch with differences in the boundary layer growth and recirculation regions. Further down-stream, all three models showed very similar velocity profiles during maximum velocity with differences occurring in the decelerating part of the pulse. Flow patterns obtained from transient 3-D computational fluid dynamics are influenced by different reconstruction methods and the pulsatility of the flow. Caution is required when analyzing models based on CT scans.

Derivatization of surface-bound peptides for mass spectrometric detection via threshold single photon ionization.

Chemical derivatization of peptides allows efficient F2 laser single photon ionization (SPI) of Fmoc-derivatized peptides covalently bound to surfaces. Laser desorption photoionization mass spectrometry using 337-nm pulses for desorption and 157.6-nm pulses for threshold SPI forms large ions identified as common peptide fragments bound to either Fmoc or the surface linker. Electronic structure calculations indicate the Fmoc label is behaving as an ionization tag for the entire peptide, lowering the ionization potential of the complex below the 7.87-eV photon energy. This method should allow detection of many molecular species covalently or electrostatically bound to surfaces.

Optimization of soil physical and chemical conditions for the bioremediation of creosote-contaminated soil.

Mispah type soil (FAO : Lithosol) contaminated with > 250 000 mg kg(-1) creosote was collected from the yard of a creosote treatment plant. The soil's carbon, nitrogen and phosphorus contents were determined. Due to creosote contamination, the carbon content of the soil was found to be 130,000 mg C kg(-1). This concentration was found to greatly affect the nitrogen content (0.08%). The phosphorus content was less affected (4.5%). It was estimated that a nutrient amendment to bring the soil to a C : N 10 : 1 would be adequate to stimulate microbial growth and creosote degradation. The soil was amended with a range of C : N ratios below and above the estimated ratio. In one of the treatments, the phosphorus content was amended. Sterile and natural controls were also set up. The soil was incubated at 30 +/- 2 degrees C on a rotary shaker at 150 rpm in the dark for six weeks. Water content was maintained at 70% field capacity. The lowest nitrogen supplementation (C : N = 25 : 1) was more effective in enhancing microbial growth (3.12E + 05) and creosote removal (68.7%) from the soil. Additional phosphorus was not very effective in enhancing the growth of microorganisms and removal of creosote. The highest nitrogen supplementation (C : N = 5 : 1) did not enhance microbial growth and creosote removal. Phenolics and lower molecular mass polycyclic aromatic hydrocarbons (PAHs) were observed to be more susceptible to microbial degradation than higher molecular mass compounds. Nutrient concentration, moisture content and pH were thus observed to play very significant roles in the utilization of creosote in soil. These results are being used for the development of a bioremediation technology for the remediation of creosote contaminated soils in a treatment plant in South Africa.

Metastatic pulmonary ameloblastoma. An unusual case.

We present a patient who had a large metastatic pulmonary ameloblastoma resected 25 years after removal of an apparently benign primary ameloblastoma of the jaw. It highlights three areas: problems with the histopathological diagnosis of pulmonary metastases using fine needle aspiration; a noted radiological improvement after a 5-year course of oral cyclophosphamide, in keeping with occasional patients who have responded to chemotherapy; and the technical difficulties of resection of a large pulmonary metastasis, particularly when it is adherent to the mediastinum.