The Effect of Oral Laxatives on Rectal Distension and Image Quality in Magnetic Resonance Imaging of the Prostate.

Introduction Increasing rectal size is associated with increased artefacts on magnetic resonance imaging (MRI) of the prostate and has the potential to degrade image quality. The objective of this study was to analyse the effect of oral laxative medication on rectal distension and image quality in prostate MRI. Methods Eighty patients prospectively received either 15 mg of oral senna (laxative group) or no medication (control group). Patients underwent prostate MRI according to standard local protocol and seven rectal dimensions on axial and sagittal images were measured. A subjective assessment of rectal distension was also made using a five-point Likert scale. Finally, artefacts on diffusion-weighted sequences were assessed using a four-point Likert scale. Results There was a small reduction in rectal diameter on sagittal images in the laxative group compared to the control group, with mean diameters of 27.1 mm and 30.0 mm respectively, p=0.02. There was no significant difference in rectal measurements of anteroposterior diameter, transverse diameter, or rectal circumference on axial imaging. Subjective scoring also demonstrated no significant difference in diffusion-weighted imaging quality between the laxative group and control group, p=0.82. Conclusion Bowel preparation with the oral laxative, senna, provided only a marginal decrease in rectal distension on one measure and no reduction in artefacts on diffusion-weighted sequences. The findings of this study do not support the routine use of this medication in patients undergoing prostate MRI.

Renal cell carcinoma presenting as painless jaundice and unintentional weight loss.

Painless jaundice and unexplained weight loss is an exceedingly rare presentation for renal cell carcinoma (RCC). Such a presentation is more typical of a hepatocellular pathology. Stauffer syndrome is a paraneoplastic syndrome seen in RCC and is characterized by deranged hepatic enzymes and in association with fever, fatigue and weight loss. These symptoms typically resolve following nephrectomy. The predominant picture of this syndrome is that of an anicteric patient. Here we report the case of a 48 year old man who presented with a 3 week history of painless jaundice, malaise, anorexia and unintentional weight loss of 10 kilograms. Imaging revealed a solid right renal mass measuring 11 cm × 11 cm × 14 cm. There were also findings consistent with the presence of an inferior vena cava thrombosis and multiple pulmonary lesions. Biopsy confirmed the pulmonary lesions as metastatic clear cell renal carcinoma. Following multi-disciplinary discussion, cytoreductive nephrectomy was recommended to the patient, however multiple paraneoplastic syndromes subsequently developed and the patient experienced hypertension, severe coagulopathy and hypercalcaemia. Subsequently, the patient opted for supportive and palliative care. The patient died 2 weeks after initial presentation. Paraneoplastic syndromes associated with RCC are often underdiagnosed due to their variety and often non-specific nature. Paraneoplastic syndromes may lead to patient presentation, where they often suggest advanced or metastatic disease, and those caring for such patients should remain vigilant as further syndromes may complicate patient care.

Interobserver Agreement in the Diagnosis of Parkinson Disease with Cardiac 123I-Metaiodobenzylguanidine Scintigraphy.

The aim of this study was to analyze the interobserver agreement of visual and quantitative assessment of cardiac 123I-metaiodobenzylguanidine scintigraphy. Methods: Planar images were acquired using a low-energy collimator. The heart-to-mediastinum (HM) ratio was adjusted for the use of a low-energy collimator, using a published formula. Interpretation was undertaken both visually and after the addition of adjusted HM ratios. Image findings were classified as normal, abnormal, or borderline. Results: The cohort consisted of 10 patients. On visual interpretation only, there was strong agreement on the interpretation of the scan (κ = 0.82, P < 0.01). Adjusted HM ratios led to a significant increase in mean ratios (1.79 vs. 1.36, P = 0.02) and, when utilized in reporting, resulted in perfect agreement (κ = 1.0, P < 0.01). Conclusion: The use of quantified HM ratios adjusted for low-energy collimator use improves on visual assessment alone and allowed for excellent interobserver agreement.

Subarachnoid haemorrhage rules in the decision for acute CT of the head: external validation in a UK cohort.

BACKGROUND: The Ottawa subarachnoid haemorrhage (SAH) rule and the Emerald SAH rule are clinical decision tools to aid in the decision for computed tomography (CT) of the head in patients attending an emergency department (ED) with acute non-traumatic headache. The objective of this study was to analyse the performance of these rules in a contemporary UK cohort. METHODS: We performed a retrospective external validation study. Patients undergoing CT of the head for the evaluation and treatment of non-traumatic headaches over a 6-month period in the ED at two tertiary centres were assessed. Each patient's Ottawa rule and Emerald rule were calculated and compared with their final diagnosis. RESULTS: The cohort consisted of 366 patients and there were 16 cases of SAH (based on CT findings or the presence of xanthochromia in cerebrospinal fluid). The Ottawa rule identified 288 patients requiring CT of the head. The sensitivity of the Ottawa rule was 100% (95% confidence interval (CI) 71-100%) and the specificity was 22% (95% CI 18-27%). The Emerald rule identified 267 patients who required CT, and achieved a sensitivity of 81% (95% CI 54-96%) and a specificity of 27% (95% CI 23-32%). CONCLUSIONS: The Ottawa SAH rule correctly identified all patients with SAH in this contemporary cohort. The Emerald rule did not perform as well in this cohort and is unsuitable for clinical use. The Ottawa rule is a useful tool to aid in the decision for CT of the head in patients presenting with acute non-traumatic headache to the ED.

Automated calculation of the right ventricle to left ventricle ratio on CT for the risk stratification of patients with acute pulmonary embolism.

OBJECTIVES: To assess the feasibility and reliability of the use of artificial intelligence post-processing to calculate the RV:LV diameter ratio on computed tomography pulmonary angiography (CTPA) and to investigate its prognostic value in patients with acute PE. METHODS: Single-centre, retrospective study of 101 consecutive patients with CTPA-proven acute PE. RV and LV volumes were segmented on 1-mm contrast-enhanced axial slices and maximal ventricular diameters were derived for RV:LV ratio using automated post-processing software (IMBIO LLC, USA) and compared to manual analysis in two observers, via intraclass coefficient correlation analysis. Each CTPA report was analysed for mention of the RV:LV ratio and compared to the automated RV:LV ratio. Thirty-day all-cause mortality post-CTPA was recorded. RESULTS: Automated RV:LV analysis was feasible in 87% (n = 88). RV:LV ratios ranged from 0.67 to 2.43, with 64% (n = 65) > 1.0. There was very strong agreement between manual and automated RV:LV ratios (ICC = 0.83, 0.77-0.88). The use of automated analysis led to a change in risk stratification in 45% of patients (n = 40). The AUC of the automated measurement for the prediction of all-cause 30-day mortality was 0.77 (95% CI: 0.62-0.99). CONCLUSION: The RV:LV ratio on CTPA can be reliably measured automatically in the majority of real-world cases of acute PE, with perfect reproducibility. The routine use of this automated analysis in clinical practice would add important prognostic information in patients with acute PE. KEY POINTS: • Automated calculation of the right ventricle to left ventricle ratio was feasible in the majority of patients and demonstrated perfect intraobserver variability. • Automated analysis would have added important prognostic information and altered risk stratification in the majority of patients. • The optimal cut-off value for the automated right ventricle to left ventricle ratio was 1.18, with a sensitivity of 100% and specificity of 54% for the prediction of 30-day mortality.

Chest X-ray in suspected lung cancer is harmful.

OBJECTIVES: The aim of this study was to analyse the use of the chest radiograph (CXR) as the first-line investigation in primary care patients with suspected lung cancer. METHODS: Of 16,945 primary care referral CXRs (June 2018 to May 2019), 1,488 were referred for suspected lung cancer. CXRs were coded as follows: CX1, normal but a CT scan is recommended to exclude malignancy; CX2, alternative diagnosis; or CX3, suspicious for cancer. Kaplan-Meier survival analysis was undertaken by stratifying patients according to their CX code. RESULTS: In the study period, there were 101 lung cancer diagnoses via a primary care CXR pathway. Only 10% of patients with a normal CXR (CX1) underwent subsequent CT and there was a significant delay in lung cancer diagnosis in these patients (p < 0.001). Lung cancer was diagnosed at an advanced stage in 50% of CX1 patients, 38% of CX2 patients and 57% of CX3 patients (p = 0.26). There was no survival difference between CX codes (p = 0.42). CONCLUSION: Chest radiography in the investigation of patients with suspected lung cancer may be harmful. This strategy may falsely reassure in the case of a normal CXR and prioritises resources to advanced disease. KEY POINTS: • Half of all lung cancer diagnoses in a 1-year period are first investigated with a chest X-ray. • A normal chest X-ray report leads to a significant delay in the diagnosis of lung cancer. • The majority of patients with a normal or abnormal chest X-ray have advanced disease at diagnosis and there is no difference in survival outcomes based on the chest X-ray findings.

Computed tomography appearances of the lung parenchyma in pulmonary hypertension.

Computed tomography (CT) is a valuable tool in the workup of patients under investigation for pulmonary hypertension (PH) and may be the first test to suggest the diagnosis. CT parenchymal lung changes can help to differentiate the aetiology of PH. CT can demonstrate interstitial lung disease, emphysema associated with chronic obstructive pulmonary disease, features of left heart failure (including interstitial oedema), and changes secondary to miscellaneous conditions such as sarcoidosis. CT also demonstrates parenchymal changes secondary to chronic thromboembolic disease and venous diseases such as pulmonary venous occlusive disease (PVOD) and pulmonary capillary haemangiomatosis (PCH). It is important for the radiologist to be aware of the various manifestations of PH in the lung, to help facilitate an accurate and timely diagnosis. This pictorial review illustrates the parenchymal lung changes that can be seen in the various conditions causing PH.

Pleural, pancreatic and prostatic involvement in IgG4-related disease mimicking pancreatic head malignancy.

We describe the case of a gentleman with pleural thickening. On follow-up imaging, dilatation of the main pancreatic and common biliary ducts was noted and an initial diagnosis of pancreatic malignancy was made. During his preoperative workup for pancreatic head malignancy, a PET-CT was performed, which demonstrated increased uptake in the pancreas, in the pleura and in the prostate gland. This raised the possibility of immunoglobulin G4-related disease (IgG4-RD), which was effectively treated with oral steroids. IgG4-RD is a well-described cause of autoimmune pancreatitis but can affect other regions, including the pleura and prostate. It is essential that radiologists are aware of the imaging findings in IgG4-RD and can direct clinicians towards this important multisystem diagnosis.

A risk calculator to inform the need for a prostate biopsy: a rapid access clinic cohort.

BACKGROUND: Prostate cancer (PCa) represents a significant healthcare problem. The critical clinical question is the need for a biopsy. Accurate risk stratification of patients before a biopsy can allow for individualised risk stratification thus improving clinical decision making. This study aims to build a risk calculator to inform the need for a prostate biopsy. METHODS: Using the clinical information of 4801 patients an Irish Prostate Cancer Risk Calculator (IPRC) for diagnosis of PCa and high grade (Gleason ≥7) was created using a binary regression model including age, digital rectal examination, family history of PCa, negative prior biopsy and Prostate-specific antigen (PSA) level as risk factors. The discrimination ability of the risk calculator is internally validated using cross validation to reduce overfitting, and its performance compared with PSA and the American risk calculator (PCPT), Prostate Biopsy Collaborative Group (PBCG) and European risk calculator (ERSPC) using various performance outcome summaries. In a subgroup of 2970 patients, prostate volume was included. Separate risk calculators including the prostate volume (IPRCv) for the diagnosis of PCa (and high-grade PCa) was created. RESULTS: IPRC area under the curve (AUC) for the prediction of PCa and high-grade PCa was 0.6741 (95% CI, 0.6591 to 0.6890) and 0.7214 (95% CI, 0.7018 to 0.7409) respectively. This significantly outperforms the predictive ability of cancer detection for PSA (0.5948), PCPT (0.6304), PBCG (0.6528) and ERSPC (0.6502) risk calculators; and also, for detecting high-grade cancer for PSA (0.6623) and PCPT (0.6804) but there was no significant improvement for PBCG (0.7185) and ERSPC (0.7140). The inclusion of prostate volume into the risk calculator significantly improved the AUC for cancer detection (AUC = 0.7298; 95% CI, 0.7119 to 0.7478), but not for high-grade cancer (AUC = 0.7256; 95% CI, 0.7017 to 0.7495). The risk calculator also demonstrated an increased net benefit on decision curve analysis. CONCLUSION: The risk calculator developed has advantages over prior risk stratification of prostate cancer patients before the biopsy. It will reduce the number of men requiring a biopsy and their exposure to its side effects. The interactive tools developed are beneficial to translate the risk calculator into practice and allows for clarity in the clinical recommendations.

Improving safety for medical students and patients during medical electives-a novel simulation-based course.

INTRODUCTION: The medical elective is a common component of undergraduate medical education in the UK and Ireland. These are often undertaken in varied hospitals and countries across the world, most of which are not related to their parent institutions, in order to explore specialties and regions of interest. However experiences are varied, with goals not always established beforehand, or indeed reached, when present. METHODS: Using a novel 20-item, self-administered questionnaire distributed via social media to 436 medical students and doctors in the UK and Republic of Ireland, we sought to delineate common elective experiences and establish what procedures and clinical scenarios medical students commonly undertake and manage during their medical electives, in order to ascertain their confidence level with each of these tasks at the time of their medical electives. We also looked to determine if there are any adverse effects or events related to these situations. Following this, we developed a simulation-based course to address knowledge and skill gaps identified in the above fields. This course was delivered to two groups of medical students from St George's University London and King's College London medical schools by the same faculty over two separate afternoons. RESULTS: We found that a significant proportion of medical students feel pressured to perform skills, which are beyond their competence level during their elective placements, putting both patient and student safety at risk. Our simulation course was successful in significantly improving key technical and non-technical skills, which would be useful for students during their medical electives.

Contrast-enhanced ultrasound of the kidney: a single-institution experience.

BACKGROUND: Focal renal masses are typically evaluated by means of triphasic contrast-enhanced CT or MRI scan but use of iodinated contrast or gadolinium is unsuitable for some patients. Contrast-enhanced ultrasound (CEUS) is an imaging alternative in this scenario but has limited availability in Ireland. AIM: The aim of the study was to retrospectively evaluate experience with selective use of CEUS for non-invasive characterization of focal renal masses in a tertiary referral institution in Ireland, with a particular focus on cystic renal lesions and the influence of CEUS on final Bosniak classification and treatment outcomes. METHODS: All cases of renal CEUS between 2009 and 2017 were identified. Imaging history, patient records, histopathology reports, urology conference notes, clinical follow-up details, details of lesion progression or stability on surveillance, biopsy and/or resection details and pre- and post-CEUS Bosniak scores were recorded. RESULTS: Thirty-one patients underwent renal CEUS (7 solid renal lesions, 21 cystic renal lesions and 3 'indeterminate' renal lesions). After CEUS, the CEUS-modified Bosniak score was upgraded in nine patients and downgraded in two patients. All three lesions upgraded from Bosniak III to IV were renal cell carcinomas. One of two lesions downgraded from Bosniak IV to III was resected (cystic nephroma) and the other showed no progression after 19 months of surveillance. CONCLUSION: CEUS is a valuable alternative to CT in assessing complex cystic or solid renal lesions where iodinated CT contrast or gadolinium is inappropriate. CEUS can also refine the Bosniak category of atypical cystic renal lesions and help facilitate treatment decisions.

Recurrent natalizumab-related aseptic meningitis in a patient with multiple sclerosis.

Natalizumab is a recombinant humanized monoclonal antibody that decreases T-cell migration into the central nervous system (CNS) through α4 integrin:adhesion-molecule inhibition, thereby increasing the risk for opportunistic CNS infection. Herein, we report a case of infusion-associated aseptic meningitis in a patient receiving natalizumab.

The Impact of Primary Treatment Strategy on the Quality of Life in Patients with Vestibular Schwannoma.

OBJECTIVE: To assess the quality of life (QoL) in a representative sample of patients with vestibular schwannoma and to ascertain the differences in outcomes associated with distinct management strategies. PATIENTS AND METHODS: Patients with vestibular schwannoma attending a tertiary referral center were asked to complete the Functional Assessment of Chronic Illness Therapy-Brain Questionnaire, which assesses QoL in 5 domains: physical, social, emotional and functional, and a brain cancer-specific domain. Results were analyzed in the overall cohort and in surgery, stereotactic radiosurgery, and conservative management subgroups. The relationship between patient clinical characteristics and QoL outcome also was analyzed by univariable and multivariable logistic regression. RESULTS: There were 83 survey respondents with an average age of participants of 57 years and a mean follow-up of 4.9 years. QoL was statistically significantly lower in the surgery subgroup within the Physical QoL domain (P = 0.039); however, there was no significant difference in overall QoL between the 3 subgroups of surgery, radiosurgery, and conservative management (P = 0.17). A poor QoL outcome was associated with the number of symptoms at diagnosis, greater tumor size, and a surgical management strategy. CONCLUSIONS: The QoL within this patient cohort was extremely variable in each management group, mirroring the heterogeneous natural history of this disease process. QoL in patients with vestibular schwannoma cannot be predicted based on management strategy alone, but a poor QoL outcome is more likely in patients with larger, symptomatic tumors that are treated surgically.

Signs and Symptoms of Acoustic Neuroma at Initial Presentation: An Exploratory Analysis.

Introduction The objective of this study was to describe the most common clinical features associated with an acoustic neuroma diagnosis and to identify those features associated with larger tumour size at initial diagnosis. Methods The clinical information of 945 consecutive patients diagnosed with acoustic neuroma at a single centre between 1992 and 2015 was analysed. Clinical features were examined and the relationship between these features and tumour size (>2.5 cm) was analysed using descriptive statistics and logistic regression analysis. Statistical analysis was performed in R version 3.1.1. Results The most common presenting symptom was a unilateral hearing loss in 752 patients (80%), with a progressive pattern in 90% of these cases. The second most common presenting symptom was unilateral tinnitus, accounting for 6.3%, while ataxia, vertigo and headache accounted for 3.8%, 3.4% and 2%, respectively. The diagnosis of acoustic neuroma was an incidental finding in 20 patients (2.1%). Temporal analysis demonstrated a downward trend in the number of patients presenting with hearing loss and an increased proportion of patients presenting with other symptoms. On multivariate analysis, larger tumour size was associated with abnormal tandem gait (odds ratio 8.9, p=0.02), subjective facial weakness (odds ratio 5.3, p< 0.001), abnormal facial sensation on examination (odds ratio 3.0, p=0.03) and headache (odds ratio 2.6, p< 0.001). Conclusion The majority of patients with acoustic neuroma present with the classic, progressive, unilateral hearing loss. However, the pattern of presentation in acoustic neuroma patients is changing. Features in the history indicative of a larger tumour are headaches and subjective facial weakness, whilst concerning features on examination are abnormal tandem gait and altered facial sensation.

European Randomised Study of Screening for Prostate Cancer (ERSPC) risk calculators significantly outperform the Prostate Cancer Prevention Trial (PCPT) 2.0 in the prediction of prostate cancer: a multi-institutional study.

OBJECTIVE: To analyse the performance of the Prostate Cancer Prevention Trial Risk Calculator (PCPT-RC) and two iterations of the European Randomised Study of Screening for Prostate Cancer (ERSPC) Risk Calculator, one of which incorporates prostate volume (ERSPC-RC) and the other of which incorporates prostate volume and the prostate health index (PHI) in a referral population (ERSPC-PHI). PATIENTS AND METHODS: The risk of prostate cancer (PCa) and significant PCa (Gleason score ≥7) in 2001 patients from six tertiary referral centres was calculated according to the PCPT-RC and ERSPC-RC formulae. The calculators' predictions were analysed using the area under the receiver-operating characteristic curve (AUC), calibration plots, Hosmer-Lemeshow test for goodness of fit and decision-curve analysis. In a subset of 222 patients for whom the PHI score was available, each patient's risk was calculated as per the ERSPC-RC and ERSPC-PHI risk calculators. RESULTS: The ERSPC-RC outperformed the PCPT-RC in the prediction of PCa, with an AUC of 0.71 compared with 0.64, and also outperformed the PCPT-RC in the prediction of significant PCa (P<0.001), with an AUC of 0.74 compared with 0.69. The ERSPC-RC was found to have improved calibration in this cohort and was associated with a greater net benefit on decision-curve analysis for both PCa and significant PCa. The performance of the ERSPC-RC was further improved through the addition of the PHI score in a subset of 222 patients. The AUCs of the ERSPC-PHI were 0.76 and 0.78 for PCa and significant PCa prediction, respectively, in comparison with AUC values of 0.72 in the prediction of both PCa and significant PCa for the ERSPC-RC (P = 0.12 and P = 0.04, respectively). The ERSPC-PHI risk calculator was well calibrated in this cohort and had an increase in net benefit over that of the ERSPC-RC. CONCLUSIONS: The performance of the risk calculators in the present cohort shows that the ERSPC-RC is a superior tool in the prediction of PCa; however the performance of the ERSPC-RC in this population does not yet warrant its use in clinical practice. The incorporation of the PHI score into the ERSPC-PHI risk calculator allowed each patient's risk to be more accurately quantified. Individual patient risk calculation using the ERSPC-PHI risk calculator can be undertaken in order to allow a systematic approach to patient risk stratification and to aid in the diagnosis of PCa.

Improving multivariable prostate cancer risk assessment using the Prostate Health Index.

OBJECTIVES: To analyse the clinical utility of a prediction model incorporating both clinical information and a novel biomarker, p2PSA, in order to inform the decision for prostate biopsy in an Irish cohort of men referred for prostate cancer assessment. PATIENTS AND METHODS: Serum isolated from 250 men from three tertiary referral centres with pre-biopsy blood draws was analysed for total prostate-specific antigen (PSA), free PSA (fPSA) and p2PSA. From this, the Prostate Health Index (PHI) score was calculated (PHI = (p2PSA/fPSA)*√tPSA). The men's clinical information was used to derive their risk according to the Prostate Cancer Prevention Trial (PCPT) risk model. Two clinical prediction models were created via multivariable regression consisting of age, family history, abnormality on digital rectal examination, previous negative biopsy and either PSA or PHI score, respectively. Calibration plots, receiver-operating characteristic (ROC) curves and decision curves were generated to assess the performance of the three models. RESULTS: The PSA model and PHI model were both well calibrated in this cohort, with the PHI model showing the best correlation between predicted probabilities and actual outcome. The areas under the ROC curve for the PHI model, PSA model and PCPT model were 0.77, 0.71 and 0.69, respectively, for the prediction of prostate cancer (PCa) and 0.79, 0.72 and 0.72, respectively, for the prediction of high grade PCa. Decision-curve analysis showed a superior net benefit of the PHI model over both the PSA model and the PCPT risk model in the diagnosis of PCa and high grade PCa over the entire range of risk probabilities. CONCLUSION: A logical and standardized approach to the use of clinical risk factors can allow more accurate risk stratification of men under investigation for PCa. The measurement of p2PSA and the integration of this biomarker into a clinical prediction model can further increase the accuracy of risk stratification, helping to better inform the decision for prostate biopsy in a referral population.

Unusual childhood presentations of abdominal non-Hodgkin's lymphoma.

Non-Hodgkin's lymphoma (NHL) is a relatively common childhood cancer that can present in a myriad of ways. It is essential that NHL is included in the differential diagnosis of children presenting with an abdominal complaint, especially those with unexplained or prolonged symptoms. We describe three acute pediatric presentations of abdominal NHL, two of which presented as acute abdomen (the first mimicking intussusception and the second appendicitis), and the third involving lower limb edema. This case series illustrates the array of presentations of abdominal NHL and the diagnostic challenges that they can provide.

Synchronous Subarachnoid Aneurysmal Hemorrhage and Medulloblastoma in a 6-Year-Old Girl.

BACKGROUND: Hemorrhage in medulloblastoma (MB) is a rare clinical entity with the undeniable potential for catastrophic repercussions. This case report highlights the first incidence of intraoperative subarachnoid hemorrhage (SAH) in a patient with MB secondary to an intracranial aneurysm. CASE DESCRIPTION: A 6-year-old girl with a left cerebellar mass, fourth ventricle effacement, and triventriculomegally had an external ventricular drain inserted, at which time blood stained cerebral spinal fluid was drained. After insertion of an external ventricular drain, imaging showed diffuse SAH. Post tumor resection scans showed a small residuum of tumor. At repeat tumor resection after chemoradiotherapy, a 2-mm internal carotid aneurysm was noted. CONCLUSIONS: Intraoperative hemorrhage in MB is a very rare occurrence. We describe the first case of hemorrhage in MB secondary to an intracranial aneurysm. MB has a predisposition to bleed spontaneously that can have catastrophic repercussions. Sudden clinical deterioration after insertion of external ventricular drainage should be susceptive of intracerebral hemorrhage. In cases of uncertain etiology, investigation of SAH with cerebral angiography is recommended.