Multimodality imaging in primary hyperparathyroidism.

Institutional variations in parathyroid adenoma localisation are largely dictated by local experience and availability of imaging investigations, with no consensus on the optimal approach. This review evaluates the role of multiple imaging techniques in primary hyperparathyroidism and highlights their advantages and limitations in different clinical contexts. A clinico-radiological review of parathyroid imaging techniques is illustrated with example cases and data from the literature. These include high-resolution ultrasound, 99mTc-sestamibi planar scintigraphy with and without thyroid subtraction techniques, integrated 99mTc-sestamibi single-photon-emission computed tomography (SPECT)/computed tomography (CT), four-dimensional (4D) CT, and other techniques, such as magnetic resonance imaging, integrated 18F-choline/11C-methionine positron-emission tomography (PET)/CT and angiographic selective venous sampling. The crucial role of parathyroid embryological and gross anatomy in informing the surgical approach to parathyroidectomy is discussed. Finally, a systematic approach to imaging is proposed to maximise the accuracy of imaging localisation of parathyroid lesions, which is crucial for optimal patient management.

Protocol-driven multidetector SPECT/CT: integration of hybrid imaging into the routine workflow of whole-body bone scintigraphy in oncology patients.

AIM: To analyse the additional clinical value of protocol-driven and selective use of multidetector single-photon-emission tomography/computed tomography (SPECT/CT) in oncology patients undergoing whole-body bone scintigraphy (BS) and to analyse reporter confidence in diagnosis with and without SPECT/CT. MATERIALS AND METHODS: During a 2-year period, 2,954 whole-body BS examinations were performed in oncology patients, with 444 (15%) undergoing additional protocol-driven SPECT/CT. Retrospective evaluation of planar BS and SPECT/CT images was performed by two experienced dual-trained nuclear medicine radiologists. The BS and SPECT/CT images were graded blindly using a five-point scale designed to evaluate the likelihood of a lesion being benign or malignant. Interpretation was applied on a per-patient basis. RESULTS: There was a 74.5% increase in definitive diagnostic classification and a 26.6% reduction in equivocal findings with SPECT/CT when compared to BS alone (p<0001). Of cases initially classified as "probably benign" on BS, 5.1% (10/193) were reclassified to "probably malignant" (1%) or "malignant" (4.1%) using the SPECT/CT data. The highest impact in reporter confidence was seen with SPECT/CT in the interpretation of lesions within the pelvis (34%), ribs (23%), lumbar spine (22%), and thoracic spine (21%). CONCLUSION: Protocol-driven, selective use of SPECT/CT imaging to augment planar BS reduces equivocal findings and improves reporter confidence whilst minimising the impact on patient and reporting workflows.

Family physicians' perceptions of pharmacists prescribing in Alberta.

Canadian pharmacists now have prescribing authority and little is documented about the physicians' perception, experience and relational dynamics evolving around the pharmacists' prescribing practice. The objective of this study was to explore Albertan family physicians' perceptions and experiences of pharmacists' prescribing practice. We used purposeful and maximum variation sampling method and semi-structured face to face or telephone interviews to collect data. From October 2014 to February 2016, we interviewed 12 family physicians in Alberta, having experience with pharmacist prescribing. Interviews were audio recorded and transcribed verbatim for analysis using an interpretive description method, guided by "Relational Coordination" theory. NVivo software was used to manage the data. Three key beliefs (i.e., renewal versus initiate new prescription, community versus team pharmacists, and "I am responsible") about pharmacist prescribing were identified. Trust and communication were prominent themes which shaped participants' collaboration with pharmacist prescribers. Participants were classified as either "collaborative" or "consultative". Participants had greater collaboration with the team pharmacist prescribers compared to community pharmacists due to a higher level of trust and ease of communication. Renewal prescribing by any pharmacist was well accepted but participants showed hesitancy in accepting pharmacist-initiated prescriptions. Our findings provide insight into interprofessional collaboration and communication between physician and pharmacist prescribers.

Clinical impact and diagnostic accuracy of 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography/computed tomography (PET/CT) brain imaging in patients with cognitive impairment: a tertiary centre experience in the UK.

AIM: To evaluate the clinical impact of combined 2-[18F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography/computed tomography (PET/CT) brain imaging performed in selected patients with cognitive impairment at a tertiary referral centre in the UK, and to assess the accuracy of FDG PET/CT to correctly establish the diagnosis of Alzheimer's dementia (AD) in "real-world" clinical practice. METHODS AND MATERIALS: Using an institutional radiology database, 136 patients were identified for inclusion in the study. FDG PET/CT was performed using a standard technique and interpreted by dual-trained radiologists and nuclear medicine physicians. Standardised questionnaires were sent to the referring clinicians to establish the final clinical diagnosis and to obtain information about the clinical impact of FDG PET/CT. RESULTS: There was a 72% questionnaire return (98/136), with mean patient follow-up of 471 (standard deviation 205) days. FDG PET/CT had an impact on patient management in 81%, adding confidence to the pre-test diagnosis in 43%, changing the pre-test diagnosis in 35%, reducing the need for further investigations in 42%, and resulting in a change in therapy in 32%. There was substantial correlation between the PET/CT diagnosis and final clinical diagnosis with a correlation (k) coefficient of 0.78 (p<0.0001). The accuracy of FDG PET/CT in diagnosis of AD was 94% (95% confidence interval [CI]: 87-99), with a sensitivity of 87% (95% CI: 75-92) and a specificity of 97% (95% CI: 87-99). CONCLUSION: FDG PET/CT brain imaging has a significant clinical impact when performed selectively in patients with cognitive impairment and shows high accuracy in the diagnosis of AD in "real-world" clinical practice.

Role of Serum Pepsinogen I and II Ratio in Screening of Gastric Carcinoma.

In spite of the global decline in its incidence and mortality, gastric carcinoma still remains a major cause of death due to cancer. Early detection of gastric carcinoma is expected to reduce mortality rates. The applications of measuring of pepsinogen I and pepsinogen II are useful in screening of gastric carcinoma. This cross sectional comparative study was done to find out the correlation of histopathological pattern of gastric carcinoma with serum pepsinogen I & II ratio in the Department of Pathology, Sylhet MAG Osmani Medical College, Sylhet, Bangladesh from January 2010 to December 2010. For these purpose 40 patients with gastric carcinoma, endoscopically visible and histopathologically proved malignant lesions were enrolled as case group. Forty subjects with normal upper GI endoscopy were taken as control. Five ml of venous blood was taken from both case and control subjects to determine serum pepsinogen I and pepsinogen II level by ELISA method, subsequently pepsinogen I and II ratio was calculated. In this study different cut off values of serum pepsinogen I and II ratio was determined and the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 70.0%, 97.5% 96.6% 76.5% and 83.8% respectively, at cut off value of 6. Which is the most suitable cut off point of serum pepsinogen I and II ratio for gastric cancer screening.

HER2 status in Gastric and Gastroesophageal Junction Adenocarcinoma.

Gastric carcinoma is a biologically heterogenous disease and survival varies among the patients with same stage. Recent studies have shown that a subset of gastric and gastroesophageal junction adenocarcinoma over express the HER2/neu protein and these patients can be treated by monoclonal antibody against HER2/neu protein. The purpose of this study was to detect the frequency of HER2 expression in gastric and gastroesophageal junction adenocarcinoma and to evaluate the relationship between HER2 expression and clinicopathological features in these patients. This descriptive cross sectional study was carried out at the Department of Pathology, Dhaka Medical College, from January 2013 to December 2014. A total of 130 patients with primary gastric and gastroesophageal junction adenocarcinomas were included in this study. All the cases were evaluated for routine histological examination and immunohistochemical examination was done for HER2/neu protein. Among the 130 cases, HER2 over expression was found in 12.3% cases and was more frequent in gastroesophageal junction (28%) than in gastric carcinoma (8.6%) (P=0.026). HER2 positivity was found significantly more in intestinal type carcinoma (19%), papillary carcinoma (63%) and in fungating growth pattern (P=0.003, 0.001 and 0.001 respectively). HER2 expression was also positive in grade-I or grade-II tumor but negative in grade-III tumor (P=0.001). No significant association of HER2 expression was found with age, sex, lymph node metastasis and extent of tumor. In conclusion it can be stated that gastric and gastroesophageal junction adenocarcinoma of intestinal type or papillary and tubular type with well to moderate differentiation can be targeted for therapy using Herceptin.

Utility of additional abdominopelvic CT in detecting occult cancer in patients with unprovoked venous thromboembolism.

AIM: To analyse the positive rate for cancer on additional abdominopelvic computed tomography (CT) in patients with unprovoked venous thromboembolism (VTE), evaluate the subsequent emergence of a cancer diagnosis in the clinical follow-up period, and identify any possible predictive factors of cancer in this cohort, which may allow better selection of patients for additional imaging. MATERIALS AND METHODS: Consecutive adult patients with VTE were retrospectively identified in two large teaching hospitals between January 2013 and June 2014, including a subset of those with unprovoked VTE. Relevant demographic data were extracted and analysed. All patients had a minimum of 12 months clinicoradiological follow-up. RESULTS: One thousand four hundred and forty-six patients with VTE were deemed eligible, of which 699 (48%) were male; the median age (range) was 66 (16-102) years. The prevalence of pre-existing cancer in these patients was 343/1446 (24%), and 388/1446 (27%) were classified as unprovoked VTE. In 12/1446 (0.8%), cancer was diagnosed synchronously with VTE on the initial imaging investigation. Additional screening imaging was performed in 232/388 (60%) including abdominopelvic CT in 205 (53%) patients with unprovoked VTE. Only five additional cancers were identified, all of these occurring in patients with clinical symptoms suspicious for cancer. None of the additional CT examinations identified any clinically occult cancer in asymptomatic patients, and subsequent mean follow-up of 22 (SD=6) months also failed to reveal any further cancer diagnosis. CONCLUSION: Contrary to the National Institute of Health and Care Excellence (NICE) guidance, the yield of performing additional abdominopelvic CT as a screening tool for occult cancer in asymptomatic patients with unprovoked VTE is negligible. A more selective and clinically-driven assessment of these patients is recommended.

Dye-sensitized InGaN nanowire arrays for efficient hydrogen production under visible light irradiation.

Solar water splitting is a key sustainable energy technology for clean, storable and renewable source of energy in the future. Here we report that Merocyanine-540 dye-sensitized and Rh nanoparticle-decorated molecular beam epitaxially grown In0.25Ga0.75N nanowire arrays have produced hydrogen from ethylenediaminetetraacetic acid (EDTA) and acetonitrile mixture solution under green, yellow and orange solar spectra (up to 610 nm) for the first time. An apparent quantum efficiency of 0.3% is demonstrated for wavelengths 525-600 nm, providing a viable approach to harness deep-visible and near-infrared solar energy for efficient and stable water splitting.

Lack of BCG vaccination and other risk factors for bacteraemia in severely malnourished children with pneumonia.

We sought to examine the factors associated with bacteraemia and their outcome in children with pneumonia and severe acute malnutrition (SAM). All SAM children of either sex, aged 0-59 months, admitted to the Dhaka Hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh with radiologically confirmed pneumonia from April 2011 to July 2012 were enrolled (n = 405). Comparison was made between pneumonic SAM children with (cases = 18), and without (controls = 387) bacteraemia. The death rate was significantly higher in cases than controls (28% vs. 8%, P < 0·01). In logistic regression analysis, after adjusting for potential confounders, the SAM children with pneumonia and bacteraemia more often had a history of lack of bacillus Calmette-Guérin (BCG) vaccination (odds ratio 7·39, 95% confidence interval 1·67-32·73, P < 0·01). The results indicate the importance of continuation of BCG vaccination which may provide benefit beyond its primary purpose.

FDG PET/CT in infection and inflammation--current and emerging clinical applications.

Integrated positron emission tomography/computed tomography (PET/CT) with the glucose analogue, 2-[(18)F]-fluoro-2-deoxy-d-glucose (FDG), is an evolving hybrid imaging technique in the evaluation of an important and diverse group of pathological conditions, which are characterised by infection and aseptic inflammation. With a rapidly expanding body of evidence, it is being increasingly recognised that, in addition to its established role in oncological imaging, FDG PET/CT also has clinical utility in suspected infection and inflammation. The technique can identify the source of infection or inflammation in a timely fashion ahead of morphological changes on conventional anatomical imaging techniques, such as computed tomography (CT) and magnetic resonance imaging (MRI), map the extent and severity of disease, identify sites for tissue sampling, and assess therapy response. FDG PET/CT exhibits distinct advantages over traditional radionuclide imaging techniques in terms of shorter duration of examination, higher spatial resolution, non-invasive nature of acquisition, ability to perform quantitative analyses, and the provision of a synergistic combination of functional and anatomical imaging. With the use of illustrative clinico-radiological cases, this article discusses the current and emerging evidence for the use of FDG PET/CT in a broad spectrum of disorders, such as fever of unknown origin, sarcoidosis, large vessel vasculitis, musculoskeletal infections, joint prosthesis or implant-related complications, human immunodeficiency virus (HIV)-related infections, and miscellaneous indications, such as IgG4-related systemic disease. It will also briefly summarise the role of more novel tracers such as FDG-labelled leukocytes and gallium-68 PET tracers in this arena.

Management of gallbladder dyskinesia: patient outcomes following positive 99mtechnetium (Tc)-labelled hepatic iminodiacetic acid (HIDA) scintigraphy with cholecystokinin (CCK) provocation and laparoscopic cholecystectomy.

AIMS: To evaluate clinical outcomes in patients with typical biliary pain, normal ultrasonic findings, and a positive (99m)technetium (Tc)-labelled hepatic iminodiacetic acid analogue (HIDA) scintigraphy with cholecystokinin (CCK) provocation indicating gallbladder dyskinesia, as per Rome III criteria, undergoing laparoscopic cholecystectomy (LC). METHODS AND MATERIALS: Consecutive patients undergoing LC for gallbladder dyskinesia were identified retrospectively. They were followed up by telephone interview and review of the electronic case records to assess symptom resolution. RESULTS: One hundred consecutive patients (median age 44; 80% female) with abnormal gallbladder ejection fraction (GB-EF <35%) were followed up for a median of 12 months (range 2-80 months). Following LC, 84% reported symptomatic improvement and 52% had no residual pain. Twelve percent had persisting preoperative-type pain of either unchanged or worsening severity. Neither pathological features of chronic cholecystitis (87% of 92 incidences when histology available) nor reproduction of pain on CCK injection were significantly predictive of symptom outcome or pain relief post-LC. CONCLUSION: In one of the largest outcome series of gallbladder dyskinesia patients in the UK with a positive provocation HIDA scintigraphy examination and LC, the present study shows that the test is a useful functional diagnostic tool in the management of patients with typical biliary pain and normal ultrasound, with favourable outcomes following surgery.

Development of an ELISA for the Pharmacokinetic Evaluation of a Murine Anti CD66 Monoclonal Antibody in Human Serum.

An enzyme-linked immunosorbent assay (ELISA) was needed to assist in the pharmacokinetic evaluation of the murine antibody conjugate CHX A" DTPA Besilesomab in serum samples in a clinical trial . A search failed to locate a validated assay that quantified murine antibodies in human serum so the purpose of this article was to develop a robust assay, validated against current guidelines. A detailed method for an ELISA to measure a murine antibody in human serum is described. The assay was validated as fit for purpose against the target values of coefficient of variation < 20% and accuracy ± 20%.

Clinical impact of FDG PET-CT on the management of patients with locally advanced cervical carcinoma.

AIM: To evaluate the impact of staging FDG PET-CT on the initial management of patients with locally advanced cervical carcinoma (LACC) and any prognostic variables predicting survival. MATERIALS AND METHODS: Retrospective analysis of consecutive patients undergoing FDG PET-CT for staging of LACC in a single tertiary referral centre, between April 2008 and August 2011. Comparison was made between MRI and PET-CT findings and any subsequent impact on treatment intent or radiotherapy planning was evaluated. RESULTS: Sixty-three patients underwent FDG PET-CT for initial staging of LACC. Major impact on management was found in 20 patients (32%), a minor impact in five (8%), and no impact in 38 (60%). In those patients where PET-CT had a major impact, 12 had more extensive local nodal involvement, five had occult metastatic disease, two had synchronous tumours, and one patient had equivocal lymph nodes on MRI characterized as negative. PET-positive nodal status at diagnosis was found to be a statistically significant predictor of relapse-free survival (p < 0.05). CONCLUSION: Staging FDG PET-CT has a major impact on the initial management of approximately one-third of patients with LACC by altering treatment intent and/or radiotherapy planning. PET-defined nodal status is a poor prognostic indicator.

Effect of compaction on bisulfide diffusive transport through MX-80 bentonite.

Canada's deep geological repository (DGR) design includes an engineered barrier system where highly compacted bentonite (HCB) surrounds the copper-coated used fuel containers (UFCs). Microbial-influenced corrosion is a potential threat to long-term integrity of UFC as bisulfide (HS-) may be produced by microbial activities under anaerobic conditions and transported via diffusion through the HCB to reach the UFC surface, resulting in corrosion of copper. Therefore, understanding HS- transport mechanisms through HCB is critical for accurate prediction of copper corrosion allowance. This study investigated HS- transport behaviour through MX-80 bentonite at dry densities 1070-1615 kg m-3 by performing through-diffusion experiments. Following HS- diffusion, bromide (Br-) diffusion and Raman spectroscopy analyses were performed to explore possible physical or mineralogical alterations of bentonite caused by interacting with HS-. In addition, accessible porosity ε was estimated using extended Archie's law. Effective diffusion coefficient of HS- was found 2.5 × 10-12 m2 s-1 and 5.0× 10-12 m2 s-1 for dry densities 1330 and 1070 kg m-3, respectively. No HS- breakthrough was observed for highly compacted bentonite (1535-1615 kg m-3) over the experimental timeframe (170 days). Raman spectroscopy results revealed that HS- reacted with iron in bentonite and precipitated as mackinawite and, therefore, it was immobilized. Finally, results of this study imply that HS- transport towards UFC will be highly controlled by the available iron content and dry density of the buffer material.

Comparison of Pain Control and Analgesic Consumption With or Without Infiltration of Bupivacaine at Port Sites after Laparoscopic Cholecystectomy.

Pain management is an essential component of all surgical procedures. Analgesics are used for this purpose but there are some complications in using them. Local anesthetics like bupivacaine can be used to reduce postoperative pain as well as analgesics consumption. The objective of this study is to observe the result of infiltration of bupivacaine at port sites and to compare the postoperative pain relief with that of opioids and NSAID administration following laparoscopic cholecystectomy for chronic calculus cholecystitis. This is a cross sectional study was conducted over one year in the Department of Surgery of Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from September 2018 to August 2019. Here total 40 patients were enrolled by purposive sampling. They were divided in two groups. One group received bupivacaine while other did not. A numerical pain scale was used as tool. Data will be recorded by peer reviewed interview and observation based semi structured data collection sheet. Data analysis was done by SPSS version 23.0. P-value was significant at (p<0.05) and determined by chi square test. Written informed consent was taken from the patient. The mean Numerical Rating Scale (NRS) score of pain at 6 hour was 2.55±0.6 in Group I and 6.8±1.15 in Group II. The mean NRS score of pain at 12 hour was 4.1±1.21 in Group I and 7.95±0.6 in Group II. The mean time of 1st analgesic administration was 13.85±1.57 hours in Group I and 2.75±0.72 hours in Group II. The mean repeat dose of analgesic was in 22±2.29 hours in Group I and 9.5±1.15 hours in Group II. In Group I one third patients (30.0%) single dose analgesic required in 1st 12 hours while in Group II almost 90.0% patients needed analgesics in 1st 12 hours. In Group I, total doses of analgesics required were 2 in 75.0% patients while in Group II at least 3 doses of analgesics were needed. In Group I only one patient needed analgesic in first 6 hours (5.0%) while in Group II, all the patients (100.0%) needed analgesics. The difference was statistically significant (p<0.05) between two groups. The patients receiving bupivacaine at port sites will experience less pain at postoperative period and will need less analgesic medications.

Demographic Characteristics of Patients with Breast Cancer in Bangladesh: A Single-Centre Study.

We performed this study to investigate the socio-demographic factors of breast cancer patients of Bangladesh. This cross-sectional study was conducted in the Department of General Surgery at Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from July 2018 to September 2019 for a period of one (1) year. All consecutive cases of breast carcinoma admitted in hospital and attended at outpatient department during the study period were selected as study population. Total 50 patients were selected. The mean age of the study patients was 51.1. Maximum number (70.0% cases) of breast cancer was belonged in 4th to 5th decade aged group. 70.0% breast cancer patients were housewives. The most of the breast carcinoma was reported in the urban people which were 78.0% cases. The percentage of educated study population was 80.0%. On religious background, 86.0% cases of breast cancer patients were Muslim. Most of breast cancer patients were sporadic in origin 94.0% cases, had no family history of breast cancer. Breast cancer was mostly distributed in pre-menopausal aged group with 82.0% cases. Ninety percent (90.0%) of the study population was come from middle class socio-economic group. In western countries, incidence of breast cancer is more in elderly aged menopause women with high socio-economic class. In this study the breast carcinoma was most prevalent among educated urban Muslim pre-menopausal housewives of age group 4th to 5th decade and most of them belonged to middle socio-economic class. The socio-demographic factors of breast cancer patients in Bangladesh are disparate from western countries in age standard, social class group and menstrual status.

Prediction of Coronary Artery Disease Severity by Using CHA2DS2-VASC-HSF Score in Patients with ST-Elevation Myocardial Infarction.

CHADS2 and CHA2DS2-VASc scores are widely used in clinical practice and include similar risk factors for the development of coronary artery disease (CAD). It is known that the factors comprising the newly defined CHA2DS2-VASC-HSF score promote atherosclerosis and associated with severity of CAD. Objective of the study was to find out the association of the CHA2DS2-VASC-HSF score with the severity of CAD in patients with ST elevation myocardial infarction (STEMI). One hundred (100) patients with STEMI were enrolled in this study after considering inclusion and exclusion criteria over a one year period from October, 2017 to September, 2018 in the Department of Cardiology, National Institute of Cardiovascular Diseases, Dhaka, Bangladesh. Coronary angiogram was done within index hospitalization and coronary artery disease severity was assessed by SYNTAX score system. Patients were divided into two groups on the basis of SYNTAX score. Patients with SYNTAX score ≥23 assigned as Group I and SYNTAX score <23 assigned as Group II. The CHA2DS2-VASC-HSF score was calculated. Cut-off value of high CHA2DS2-VASC-HSF score was ≥4.0. In this study mean age of study population was 51.8±9.8, male patients were predominant (79.0%). Among the studied patients, highest percentage had history of smoking followed by hypertension, diabetes mellitus and family history of CAD in Group I patients. It was found that DM and family history of CAD and history of stroke/TIA were significantly higher in Group I than Group II. An increasing trend of SYNTAX score was observed according to the CHA2DS2-VASc-HSF score. SYNTAX score was significantly higher in CHA2DS2-VASc-HSF score ≥4 than CHA2DS2-VASc-HSF score <4 (26.3±6.3 vs. 12.1±7.7, p<0.001). Patients with CHA2DS2-VASC-HSF score ≥4 had severe coronary artery disease than CHA2DS2-VASC-HSF score <4 assessed by SYNTAX score with 84.4% sensitivity and 81.9% specificity (AUC:0.83, 95% CI: 0.746-0.915, p<0.001). CHA2DS2-VASc-HSF score was positively correlated with the severity of CAD. This score could be considered as a predictor of coronary artery disease severity.

Imaging slit-coupled surface plasmon polaritons using conventional optical microscopy.

We develop a technique that now enables surface plasmon polaritons (SPPs) coupled by nano-patterned slits in a metal film to be detected using conventional optical microscopy with standard objective lenses. The crux of this method is an ultra-thin polymer layer on the metal surface, whose thickness can be varied over a nanoscale range to enable controllable tuning of the SPP momentum. At an optimal layer thickness for which the SPP momentum matches the momentum of light emerging from the slit, the SPP coupling efficiency is enhanced about six times relative to that without the layer. The enhanced efficiency results in distinctive and bright plasmonic signatures near the slit visible by naked eye under an optical microscope. We demonstrate how this capability can be used for parallel measurement through a simple experiment in which the SPP propagation distance is extracted from a single microscope image of an illuminated array of nano-patterned slits on a metal surface. We also use optical microscopy to image the focal region of a plasmonic lens and obtain results consistent with a previously-reported results using near-field optical microscopy. Measurement of SPPs near a nano-slit using conventional and widely-available optical microscopy is an important step towards making nano-plasmonic device technology highly accessible and easy-to-use.

Factors associated with nonadherence to thiopurines in adolescent and adult patients with inflammatory bowel disease.

OBJECTIVES: We hypothesised that nonadherence to thiopurines is more common in adolescents than in adults with inflammatory bowel disease. METHODS: We sought factors associated with thiopurine nonadherence defined by thiopurine metabolite levels. RESULTS: Multivariate logistic regression confirmed that adolescents (odds ratio [OR] 4.6 [95% confidence interval [CI] 1.9-11.5]; P < 0.01) compared with adults, patients with Crohn disease (OR 3.3 [CI 1.1-10.5] P = 0.04) compared with ulcerative colitis, and patients living in more socially deprived areas (OR 1.03 [CI 1.0-1.1] P = 0.02) were more likely to be nonadherent to thiopurines. CONCLUSIONS: Adolescents are more frequently nonadherent than adults: prospective studies are required to determine the reasons for nonadherence in adolescents.

Delayed response assessment with FDG-PET-CT following (chemo) radiotherapy for locally advanced head and neck squamous cell carcinoma.

AIMS: To analyse the diagnostic accuracy of delayed response assessment 2-[¹8F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography-computed tomography (PET-CT) following (chemo)radiation for locally advanced head and neck squamous cell carcinoma (HNSCC). MATERIAL AND METHODS: Forty-four consecutive patients who underwent a baseline and response assessment using FDG PET-CT for HNSCC following (chemo)radiation between August 2008 and April 2011 were identified retrospectively. Clinicopathological findings and serial clinical follow-up provided the reference standard. RESULTS: Median follow-up was 14 months (range 5-43 months). Response assessment FDG PET-CT was performed at 16.8 weeks (inter-quartile range 15.8-18.6 weeks). Thirty-one out of 44 (70%) response assessment examinations showed a complete metabolic response. Seven out of 40 (18%) assessable primary tumours were positive. Eight out of 41 (20%) patients with pre-treatment nodal disease had equivocal or positive FDG uptake at response assessment. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for primary disease and nodal disease were 100, 89, 43, 100, and 100%, and 92, 63, and 100%, respectively. Seven patients had residual FDG-negative soft tissue detectable on the unenhanced CT component of the response assessment images; all remained disease free after clinical observation. Distant metastases were detected on response assessment FDG PET-CT in four out of the 44 patients (10%). CONCLUSION: The diagnostic accuracy of response assessment with FDG PET-CT performed at approximately 16 weeks post-(chemo)radiotherapy is good. The very high NPV of a complete metabolic response can be used to guide management decisions. Although the PPV is limited for local residual disease, FDG PET-CT is a powerful screening tool for the detection of interim metastatic disease.