Current Medical Imaging - Volume 15, Issue 9, 2019

Background: The skeleton is one of the frequent site of metastases in advanced cancer. Prostate, breast and renal cancers mostly metastasize to bone. Discussion: Malignant tumors lead to significant morbidity and mortality. Identification of bone lesions is a crucial step in diagnosis of disease at early stage, monitoring of disease progression and evaluation of therapy. Diagnosis of cancer metastases is based on uptake of bone-targeted radioactive tracer at different bone remodeling sites. Conclusion: This manuscript summarizes already established and evolving nuclear medicine modalities (e.g. bone scan, SPECT, SPECT/CT, PET, PET/CT) for imaging of bone metastases.

Background: Cancer is a disease which involves the abnormal cell growth that has the potential of dispersal to other parts of the body. Among various conventional anatomical imaging techniques for cancer diagnosis, Magnetic Resonance Imaging (MRI) provides the best spatial resolution and is noninvasive. Current efforts are directed at enhancing the capabilities of MRI in oncology by adding contrast agents. Discussion: Recently, the superior properties of nanomaterials (extremely smaller in size, good biocompatibility and ease in chemical modification) allow its application as a contrast agent for early and specific cancer detection through the MRI. The precise detection of cancer region from any imaging modality will lead to a thriving treatment for cancer patients. The better localization of radiation dose can be attained from MRI by using suitable image processing algorithms. As there are many works that have been proposed for automatic detection for cancers, the effort is also put in to provide an effective survey of Computer Aided Diagnosis (CAD) system for different types of cancer detection with increased efficiency based on recent research works. Even though there are many surveys on MRI contrast agents, they only focused on a particular type of cancer. This study deeply presents the use of nanocontrast agents in MRI for different types of cancer diagnosis. Conclusion: The main aim of this paper is to critically review the available compounds used as nanocontrast agents in MRI modality for different types of cancers. It also includes the review of different methods for cancer cell detection and classification. A comparative analysis is performed to analyze the effect of different CAD systems.

Background: The many causes of Intracerebral Haemorrhage (IH) can be difficult to differentiate. However, there are imaging features that can provide useful clues. This paper aims to provide a pictorial review of the common causes of IH, to identify some distinguishing diagnostic features and to provide guidance on subsequent imaging and follow up. It is hoped that this review would benefit radiology and non-radiology consultants, multi-professional workers and trainees who are commonly exposed to unenhanced CT head studies but are not neuroradiology specialists. Discussion: In the absence of trauma, Spontaneous Intracerebral Haemorrhage (SIH) can be classified as idiopathic or secondary. Secondary causes of IH include hypertension and amyloid angiopathy (75-80%) and less common pathologies such as vascular malformations (arteriovenous malformations, aneurysms and cavernomas), malignancy , venous sinus thrombosis and infection. SIH causes between 10 to 15% of all strokes and has a higher mortality than ischaemic stroke. Trauma is another cause of IH with significant mortality and some of the radiological features will be reviewed. Conclusion: Unenhanced CT is a mainstay of acute phase imaging due to its availability and, sensitivity and specificity for detecting acute haemorrhage. Several imaging features can be identified on CT and, along with clinical information, can provide some certainty in diagnosis. For those suitable and where diagnostic uncertainty remains CT angiogram, time-resolved CT angiography and catheter angiography can help identify underlying AVMs, aneurysms, cavernomas and vasculitides. MRI is more sensitive for the detection of subacute and chronic haemorrhage and identification of underlying mass lesions.

Background: Breast cancer is the commonest cancer affecting Malaysian women, accounting for an estimated 30% of all new cancer diagnosed annually. Improvements in breast cancer management have increased the breast cancer survival rate in Malaysia. Clinical and radiological surveillance of the treated breast is vital, as early detection of recurrence improves patient’s survival rate. Discussion: As surgery and radiotherapy alter the appearance of the breasts, distinguishing between recurrence and benign post-surgical changes can be challenging radiologically due to overlapping features. Despite this, differentiation between these two entities is usually possible by recognizing characteristic features of post-treatment sequelae and the evolution of the appearance of the conservatively treated breast by comparing interval findings on serial studies. Conclusion: This pictorial review aims to describe the typical and unusual features of post-treated breasts in the multimodality imaging workup of an established breast care centre in a teaching hospital in Malaysia.

Background: Lung cancers or (Bronchogenic-Carcinomas) are the disease in certain parts of the lungs in which irresistible multiplication of abnormal cells leads to the inception of a tumor. Lung cancers consisting of two substantial forms based on the microscopic appearance of tumor cells are: Non-Small-Cell-Lung-Cancer (NSCLC) (80 to 85%) and Small-Cell-Lung-Cancer (SCLC) (15 to 20%). Discussion: Lung cancers are existing luxuriantly across the globe and the most prominent cause of death in advanced countries (USA & UK). There are many causes of lung cancers in which the utmost imperative aspect is the cigarette smoking. During the early stage, there is no perspicuous sign/symptoms but later many symptoms emerge in the infected individual such as insomnia, headache, pain, loss of appetite, fatigue, coughing etc. Lung cancers can be diagnosed in many ways, such as history, physical examination, chest X-rays and biopsy. However, after the diagnosis and confirmation of lung carcinoma, various treatment approaches are existing for curing of cancer in different stages such as surgery, radiation therapy, chemotherapy, and immune therapy. Currently, novel techniques merged that revealed advancements in detection and curing of lung cancer in which mainly includes: microarray analysis, gene expression profiling. Conclusion: Consequently, the purpose of the current analysis is to specify and epitomize the novel literature pertaining to the development of cancerous cells in different parts of the lung, various preeminent approaches of prevention, efficient diagnostic procedure, and treatments along with novel technologies for inhibition of cancerous cell growth in advance stages.

Objective: This study evaluated how much of the myocardium was hibernating in patients with left ventricle dysfunction and/or comorbidities who planned to undergo either surgical or interventional revascularization. Furthermore, this study also identified which irrigation areas of the coronary arteries presented more scar and hibernating tissue. Methods: At rest, Tc-99m MIBI SPECT and cardiac F-18 FDG PET/CT images collected between March 2009 and September 2016 from 65 patients (55 men, 10 women, mean age 64±12) were retrospectively analyzed in order to evaluate myocardial viability. The areas with perfusion defects that were considered metabolic were accepted as hibernating myocardium, whereas areas with perfusion defects that were considered non-metabolic were accepted as scar tissue. Results: Perfusion defects were observed in 26% of myocardium, on average 48% were associated with hibernation whereas other 52% were scar tissue. In the remaining Tc-99m MIBI images, perfusion defects were observed in the following areas in the left anterior descending artery (LAD; 31%), in the right coronary artery (RCA; 23%) and in the Left Circumflex Artery (LCx; 19%) irrigation areas. Hibernation areas were localized within the LAD (46%), LCx (54%), and RCA (64%) irrigation areas. Scar tissue was also localized within the LAD (54%), LCx (46%), and RCA (36%) irrigation areas. Conclusion: Perfusion defects are thought to be the result of half hibernating tissue and half scar tissue. The majority of perfusion defects was observed in the LAD irrigation area, whereas hibernation was most often observed in the RCA irrigation area. The scar tissue development was more common in the LAD irrigation zone.

Aim: The aim of our study was to determine whether the diffusion properties of the auditory pathways alter between patients with Neurofibromatosis type 1 (NF1) and the healthy subjects. DTI can well demonstrate FA and ADC changes in auditory tracts and it may be a guide to identify the candidates for hearing loss among NF1 children. Methods: The study population consisted of 43 patients with NF1 and 21 healthy controls. Diffusion tensor imaging (DTI) was used to measure apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values from lemniscus lateralis, colliculus inferior, corpus geniculatum mediale and Heschl's gyrus. The results were compared with those of the control group. Results: The ADC values of lateral lemniscus, colliculus inferior and corpus geniculatum mediale were significantly higher in NF1 compared to those of the control group. On the other hand, decreased FA values were observed in lateral lemniscus and colliculus inferior in patients with NF1. Conclusion: The increase in ADC and reduction in FA in the auditory pathways of patients with NF1 may suggest microstructural alterations, such as a decrease in the number of axons, edema or inflammation in the auditory tracts.

Background: Autism Spectrum Disorder (ASD) is a complex developmental disorder in which neurological basis is largely unknown. The Corpus Callosum (CC) is the main commissure that connects the cerebral hemispheres. Previous evidence suggests the involvement of the CC in the pathophysiology of autism. Aim: The aim of our study is to assess whether there were any changes in Corpus Callosum (CC) area and volume and to reveal the relationship between Diffusion Tensor Imaging (DTI) features in genu and splenium of corpus callosum in children with ASD. Methods: Eighteen patient and 15 controls were recruited. The volumetric sagittal TI images were used to provide measurements of midsagittal corpus callosum surface area while FA, MD, RD, and ADC values were extracted from genu and splenium of corpus callosum after which the correlation in the area and volume in ASD children was examined. Results: CC area and volume in children with ASD were decreased than controls. FA values obtained from the genu and splenum of CC were significantly lower and RD values were significantly higher. A positive correlation was observed between the FA of the genu and splenium and area and volume of the CC. There was a negative correlation between ADC, MD and RD of CC and area and volume measurements. Conclusion: The conclusions in the interrelations of morphometric and DTI data may demonstrate a likelihood of damages in the axons and cortical neurons. The results showed that there existed microstructural damages from the DTI findings. Furthermore, the decrease in FA could be a representation of the reduction in the myelination in nerve pathways, impaired integrity, reduced axonal density, and organization. Indeed, the changes in volumetric and microstructural of CC could be useful in evaluating underlying pathophysiology in children with autism.

Background: The exact morbidity of myocarditis is unknown, as the treatment is generally delayed in virtue of misdiagnosis or missed diagnosis. Aim: The aim of this study was to identify prognostic factors of left-ventricular remodeling on CMRI performed in patients with pathological proven myocarditis. Methods: Sixty-two cases with various presentations of myocarditis (39 cases with heart failure; 23 cases with arrhythmias) were selected. All patients, who underwent coronary angiography, endomyocardial biopsy, were divided into positive-remodeling and negative-remodelling groups to analyse LGE and cardiac cine parameters at presentation and subsequent to 3 months. Results: Comparison of two subgroups in CMRI is as follows: positive LGE (65.6% vs. 86.7%; p<0.05), LVEF (41.3±14.8% vs. 37.6±10.1%; p=0.62), (25.7±2.0% vs. 24.0±2.5%; p=0.81), (44.5±3.9mm vs. 46.3±5.4mm; p=0.76), (129.1±8.5ml vs. 135.3±12.2ml; p=0.26), (74.8±7.3ml vs. 79.1±10.0ml; p=0.55), (52.0±5.7g vs. 49.6±6.5g; p=0.71), (34.9±3.5ml vs. 32.4±6.2ml; p=0.68), (3.8±0.7L/min vs. 3.1±0.5L/min; p=0.64), (2.9±0.6L/min*m2 vs. 2.7±0.5L/min*m2; p=0.79). Conclusion: LGE-MRI is rewarding as an independent predictor in left-ventricular positive and negative remodelling of myocarditis.

Background: Cutis Verticis Gyrata (CVG) is a rare skin disease caused by overgrowth of the scalp, presenting as cerebriform folds and wrinkles. CVG can be classified into two forms: primary (essential and non-essential) and secondary. The primary non-essential form is often associated with neurological and ophthalmological abnormalities, while the primary essential form occurs without associated comorbidities. Discussion: We report on a rare case of primary essential CVG with a 4-year history of normal-colored scalp skin mass in the parietal-occipital region without symptom in a 34-year-old male patient, retrospectively summarizing his pathological and Computer Tomography (CT) and magnetic resonance imaging (MRI) findings. The major clinical observations on the CT and MR sectional images include a thickened dermis and excessive growth of the scalp, forming the characteristic scalp folds. With the help of CT and MRI Three-dimensional (3D) reconstruction techniques, the characteristic skin changes could be displayed intuitively, providing more evidence for a diagnosis of CVG. At the 5-year followup, there were no obvious changes in the lesion. Conclusion: Based on our observations, we propose that not all patients with primary essential CVG need surgical intervention, and continuous clinical observation should be an appropriate therapy for those in stable condition.