Magnetic resonance imaging of the ankle: Pathology of the lateral and posterior compartments.

Magnetic resonance imaging (MRI) is the gold standard for imaging the tendons and the ligaments of the ankle. MRI combines excellent tissue contrast and accurate anatomic delineation of joint structures. In the first article of this series, we discussed a compartmental approach to the interpretation of ankle pathology focusing on the anterior and medial compartments. This article will complete the MR review of the ankle, with a focus on the lateral and posterior compartments of the ankle.

Magnetic resonance imaging of the ankle: Pathology of the anterior and medial compartments.

Magnetic resonance imaging (MRI) is the gold standard for imaging the tendons and the ligaments of the ankle. MRI combines excellent tissue contrast and accurate anatomic delineation of joint structures. In this pictorial essay, the first of two parts, we delineate the ankle into anatomic compartments and use this as a template for describing pathology in each compartment.

Friction Syndromes of the Knee.

The knee is a complex joint with many fascial and ligamentous interactions. The movement in multiple planes makes the knee a prime site for friction syndromes, especially in active individuals. The most common friction syndrome is the iliotibial band friction syndrome. This occurs commonly in runners and cyclists and can be diagnosed clinically in a patient with lateral knee pain during activity. The anterior fat pads of the knee can also be the site of friction syndromes, most often in the Hoffa fat pad. Edema here can be located in the superolateral aspect of the fat pad when associated with patellar abnormalities, or diffusely when impingement is due to other causes. Edema of the quadriceps or prefemoral fat pad may also cause anterior knee pain and may be diagnosed with magnetic resonance imaging. The posteromedial friction syndrome and medial tibial crest syndrome are rare causes of medial knee pain highly active individuals.

The Lateral Knee Radiograph: A Detailed Review.

Initial imaging evaluation for a variety of knee pathologies often begins with a radiographic series. Depending on the specific indication, this will include at least two different projections of the knee. In most cases, these are the anteroposterior and lateral radiographs of the affected knee, and sometimes with the contralateral knee for comparison. Typically, knee pathologies visible on lateral view can also be appreciated on the anteroposterior view. However, several pathologic processes occur in anatomic locations typically obscured on other projections because of superimposed osseous structures. Examples of these pathologies include injuries involving the quadriceps or patellar tendons, avulsion fractures involving anterior or posterior structures, and many soft-tissue injuries. Knowledge of the relevant anatomy and typical pathologies typically visualized on the lateral radiograph of the knee is imperative to avoid overlooking these disease processes.

An unusual case of acute otitis media resulting in Gradenigo syndrome: CT and MRI findings.

With the widespread use of antibiotics, Gradenigo syndrome is a rare complication of acute otitis media (AOM) and acute mastoiditis. It is an uncommon form of petrous apicitis and can be life-threatening. We report the case of a 14-year-old female with unresolved AOM, who developed otorrhea, ipsilateral headaches, diplopia and raised inflammatory markers. Magnetic Resonance Imaging (MRI) demonstrated features of petrous apicitis and confirmed the suspicion of Gradenigo syndrome. The objective of this clinical case report is to highlight this unusual syndrome together with its radiological appearance to improve its diagnosis and management.

Knockdown of vps54 aggravates tamoxifen-induced cytotoxicity in fission yeast.

Tamoxifen (TAM) is an anticancer drug used to treat estrogen receptor (ER)‒positive breast cancer. However, its ER-independent cytotoxic and antifungal activities have prompted debates on its mechanism of action. To achieve a better understanding of the ER-independent antifungal action mechanisms of TAM, we systematically identified TAM-sensitive genes through microarray screening of the heterozygous gene deletion library in fission yeast (Schizosaccharomyces pombe). Secondary confirmation was followed by a spotting assay, finally yielding 13 TAM-sensitive genes under the drug-induced haploinsufficient condition. For these 13 TAM-sensitive genes, we conducted a comparative analysis of their Gene Ontology (GO) 'biological process' terms identified from other genome-wide screenings of the budding yeast deletion library and the MCF7 breast cancer cell line. Several TAM-sensitive genes overlapped between the yeast strains and MCF7 in GO terms including 'cell cycle' (cdc2, rik1, pas1, and leo1), 'signaling' (sck2, oga1, and cki3), and 'vesicle-mediated transport' (SPCC126.08c, vps54, sec72, and tvp15), suggesting their roles in the ER-independent cytotoxic effects of TAM. We recently reported that the cki3 gene with the 'signaling' GO term was related to the ER-independent antifungal action mechanisms of TAM in yeast. In this study, we report that haploinsufficiency of the essential vps54 gene, which encodes the GARP complex subunit, significantly aggravated TAM sensitivity and led to an enlarged vesicle structure in comparison with the SP286 control strain. These results strongly suggest that the vesicle-mediated transport process might be another action mechanism of the ER-independent antifungal or cytotoxic effects of TAM.

Airway Pressure Release Ventilation Combined With Prone Positioning in Acute Respiratory Distress Syndrome: Old Tricks New Synergy: A Case Series.

Airway pressure release ventilation (APRV) shares several overlapping mechanisms with prone positioning in improving ventilation-perfusion mismatch in patients with acute respiratory distress syndrome (ARDS). However, the combination of APRV and prone positioning is seldom performed because assist/controlled ventilation remains the mainstay ventilatory mode. We describe 5 cases of severe ARDS where APRV and prone positioning were applied. All patients' partial pressure of arterial oxygen (PaO2):inspired oxygen concentration (FiO2) ratios improved after treatment, and 3 patients were extubated within 72 hours of turning supine. In our experience, APRV can be safely used in the prone position in a select subgroup of ARDS patients with resulting significant oxygenation improvement.

Videolaryngoscope-Assisted Double-Lumen Endotracheal Tube Intubation in an Awake Patient With Known Difficult Airway and Bronchopleural Fistula: A Case Report.

Awake endotracheal intubation is the technique of choice to secure the airway when both mask ventilation and intubation are anticipated to be difficult. We present a case of a patient with a known difficult airway, bronchopleural fistula (BPF), and acute respiratory distress syndrome (ARDS) who was intubated with a double-lumen endotracheal tube (DL ETT) under awake condition using a videolaryngoscope. Independent lung ventilation (ILV) was instituted because of the BPF. The patient was treated successfully for ARDS and discharged home. To our knowledge, this is the first reported case of successful videolaryngoscope-assisted DL ETT intubation in an awake patient.

Efficacy of intubation performed by trainees on patients in the lateral position.

INTRODUCTION: Anaesthetists may be called upon to emergently secure the airway of a laterally positioned patient. Intubating a patient's trachea in the lateral position may be difficult due to unfamiliarity. This exploratory study aimed to investigate the success rate of lateral intubation performed by novices in a controlled setting. METHODS: In this observational study, all patients who presented for elective surgery requiring the lateral position with planned lateral intubation at Singapore General Hospital were included. The trainee assigned to each patient had no prior indication of the proposed lateral intubation until the start of the case. Verbal instructions were given before the start of and during the procedure. The consultant anaesthetist in attendance could intervene at any point to prevent patient harm or if the trainee requested assistance. Time to intubation, adjuncts used and complications encountered were recorded. RESULTS: A total of 44 consecutive patients were included in this study. The trainees completed 42 of the 44 lateral intubations, with 41 being successfully performed on the first attempt. All patients were intubated successfully in a lateral position within two attempts. The mean duration of intubation was 57.3 ± 36.4 seconds. There was no difference between left and right lateral intubation. Other than one episode of transient desaturation on pulse oximetry, there were no complications. CONCLUSION: Lateral intubation by trainees had a high success rate when supervised by an experienced operator. Intubation of patients in unconventional positions using routine airway equipment should be included in airway training for trainees.

miR-335 and miR-363 regulation of neuroblastoma tumorigenesis and metastasis.

BACKGROUND: microRNA (miRNA) functions broadly as post-transcriptional regulators of gene expression, and disproportionate miRNAs can result in dysregulation of oncogenes in cancer cells. We have previously shown that gastrin-releasing peptide receptor (GRP-R) signaling regulates tumorigenicity of neuroblastoma cells. Herein, we sought to characterize miRNA profile in GRP-R silenced neuroblastoma cells, and to determine the role of miRNAs on tumorigenicity and metastatic potential. METHODS: Human neuroblastoma cell lines, BE(2)-C and SK-N-SH, were used for our study. Stably transfected GRP-R silenced cells were assessed for miRNA profiles. Cells were transfected with miR-335, miR-363, or miR-CON, a nontargeting control, and in vitro assays were performed. In vivo functions of miR-335 and miR-363 were also assessed in a spleen-liver metastasis murine model. RESULTS: GRP-R silencing significantly increased expression of miR-335 and miR-363 in BE(2)-C cells. Overexpression of miR-335 and miR-363 decreased tumorigenicity as measured by clonogenicity, anchorage-independent growth, and metastasis determined by cell invasion assay and liver metastasis in vivo. CONCLUSION: We report, for the first time, that GRP-R-mediated tumorigenicity and increased metastatic potential in neuroblastoma are regulated, in part, by miR-335 and miR-363. A better understanding of the anti-tumor functions of miRNAs could provide valuable insights to discerning molecular mechanisms responsible for neuroblastoma metastasis.

MRI and US of gluteal tendinopathy in greater trochanteric pain syndrome.

Greater trochanteric pain syndrome is commonly due to gluteus minimus or medius injury rather than trochanteric bursitis. Gluteal tendinopathy most frequently occurs in late-middle aged females. In this pictorial review the pertinent MRI and US anatomy of the gluteal tendon insertions on the greater trochanter and the adjacent bursae are reviewed. The direct (peritendinitis, tendinosis, partial and complete tear) and indirect (bursal fluid, bony changes and fatty atrophy) MRI signs of gluteal tendon injury are illustrated. The key sonographic findings of gluteal tendinopathy are also discussed.

Metastatic adenocarcinoma mimicking 'target sign' of cerebral tuberculosis.

We present a 74-year-old male ex-smoker presenting with a 6-week history of personality change, confusion and headache. Magnetic resonance imaging revealed multiple supratentorial and infratentorial parenchymal masses, predominately in the frontal and parietal lobe white matter. A thin enhancing halo was demonstrated with central low signal intensity on T(1)-and T(2)-weighted imaging compatible with calcification. A tiny extra-axial lesion was also noted near the right cerebellopontine angle. Computed tomography (CT) scan confirmed the finding of a 'target' lesion with a central core of calcification and a ring of enhancement. The 'target sign' of intracerebral tuberculomata was first described in 1979 and reported to be pathognomic for this diagnosis in 1988. However, cerebral tuberculosis was considered unlikely clinically because the patient had recently completed a 12-month course of therapy for Mycobacterium avium complex respiratory infection with agents also active against Mycobacterium tuberculosis. He was afebrile and blood tests did not support an inflammatory process. Subsequent histopathology demonstrated metastatic papillary adenocarcinoma and immunohistochemical studies revealed the origin to be that of primary lung carcinoma. A spiculated pulmonary nodule was seen on CT scan but previous bronchoscopy failed to demonstrate malignant cells. In summary, the 'target sign' is a non-specific radiologic finding but most commonly indicates cerebral tuberculoma or metastatic adenocarcinoma in the appropriate clinical context.

Tophaceous gout in the cervical spine.

Gout is a common metabolic disorder typically affecting the distal joints of the appendicular skeleton. Involvement of the axial skeleton, particularly the facet joints and posterior column of the cervical spine, is rare. This case report highlights such a presentation in a 76-year old female who presented with cervical spine pain following a fall. Her radiological findings were suggestive of a destructive metastatic process. Histological diagnosis confirmed tophaceous gout.

Small bowel perforation due to a plastic bread bag clip: the case for clip redesign.

Complications of ingested plastic bread bag clips include small bowel perforation, obstruction, dysphagia, gastrointestinal bleeding and colonic impaction. There have been at least 10 cases of small bowel perforation reported in the published literature. The present paper reports this unusual cause of bowel perforation, which we believe could be prevented by improving the design of this relatively modern device or even by changing the method of sealing bread bags altogether. Interestingly, the date on the offending bread bag clip preceded the presentation of the patient by 2.5 years.