X-Ray and CT Scan Based Prediction of Best Fit Tracheostomy Tube-A Pilot Study.

Tracheostomy is a commonly performed intervention in patients requiring ventilatory support. The insertion of inappropriately sized tracheostomy tubes carries a risk of decannulation, tissue damage, ventilatory difficulties, premature tube change or discomfort. Currently, no clear guidelines exist in determining the most appropriate size tube. Imaging of the airway preoperatively could aid clinical judgement and reduce risk. Patients included adult critical care patients who had appropriate preoperative imaging. The computed tomography scans and chest radiographs of patients were reviewed. Measurements of the airway were taken and scaled to the known internal diameter of an endotracheal tube. A four-point scoring system was developed to identify patients better suited to a non-standard sized tracheostomy tube. Data from 23 patients was analyzed using the Statistical Package for Social Sciences™ (SPSS). Four measured points on imaging corresponded to the patients' appropriate tracheostomy tube size. Appropriate tracheostomy size correlates with tracheal diameter at endotracheal tube tip (r2 = 0.135), carina (r2 = 0.128), midpoint of larynx to carina (r2 = 0.146), bronchial diameter at the left mainstem (r2 = 0.323), and intrathoracic tracheal length (r2 = 0.23). Among our cohort, a score of 4 predicts the need for a larger tracheostomy tube. Simple imaging provides accurate measurement of patients' airway dimensions. Our method ensures tube size is selected according to patient airway size, and potentially reduces the risks associated with inappropriate sizing.

Unusual Sites of High-Grade Neuroendocrine Carcinomas: A Case Series and Review of the Literature.

BACKGROUND Neuroendocrine tumors (NETs) encompass a diverse group of varying clinicopathological entities arising from cells of the endocrine and nervous systems. The presentation of these unique tumors can range from occult disease discovered incidentally to hyperactive, metastatic secretory tumors. NETs most commonly originate in the gastrointestinal and respiratory tract, although they may occur at any site in the body due to the wide distribution of neuroendocrine cells. Their classification system is complex and continues to evolve, and the current system uses histological grade in defining these subtypes. Neuroendocrine carcinomas (NECs), or high-grade, poorly-differentiated NETs, are the most aggressive subtype. Surgical resection remains the primary treatment modality and may be curative, thus early diagnosis is paramount. Management of advanced NETs remains both a diagnostic and therapeutic challenge; however, advances in our understanding of these unique neoplasms as well as an evolving classification system has led to the development of adjunctive therapeutic approaches aimed to minimize morbidity and improve patient outcomes. CASE REPORT We present 6 cases of unusual sites of high-grade neuroendocrine carcinomas involving the cervix, gallbladder, oesophagus, ovary, prostate, and urinary bladder. CONCLUSIONS Our case series highlights the heterogenous and aggressive nature of this subtype of NETs as well as their diagnostic and therapeutic difficulties. We also review the evolution of the NET classification system and its impact on the management of these malignancies.

Repeatability of two-dimensional chemical shift imaging multivoxel proton magnetic resonance spectroscopy for measuring human cerebral choline-containing compounds.

AIM: To investigate the repeatability of proton magnetic resonance spectroscopy in the in vivo measurement of human cerebral levels of choline-containing compounds (Cho). METHODS: Two consecutive scans were carried out in six healthy resting subjects at a magnetic field strength of 1.5 T. On each occasion, neurospectroscopy data were collected from 64 voxels using the same 2D chemical shift imaging (CSI) sequence. The data were analyzed in the same way, using the same software, to obtain the values for each voxel of the ratio of Cho to creatine. The Wilcoxon related-samples signed-rank test, coefficient of variation (CV), repeatability coefficient (RC), and intraclass correlation coefficient (ICC) were used to assess the repeatability. RESULTS: The CV ranged from 2.75% to 33.99%, while the minimum RC was 5.68%. There was excellent reproducibility, as judged by significant ICC values, in 26 voxels. Just three voxels showed significant differences according to the Wilcoxon related-samples signed-rank test. CONCLUSION: It is therefore concluded that when CSI multivoxel proton neurospectroscopy is used to measure cerebral choline-containing compounds at 1.5 T, the reproducibility is highly acceptable.

Lipomas of the submandibular space: case report of a sialolipoma and review of diagnostic investigations available.

This report describes and discusses the radiologic investigations available for the investigation of fatty tumors of the submandibular triangle, with a focus on sialolipomas. A 33-year-old woman presented with a 3-year history of a slowly growing, painless mass in her right submandibular region. She underwent multiple imaging modalities before having a histologic diagnosis of a sialolipoma. To the best of the authors' knowledge, this is the first reported case using ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI) for investigation of a sialolipoma of the submandibular gland region. Ultrasound and fine-needle aspiration offer a tentative diagnosis of a lipoma without the associated radiation and cost associated with CT and MRI, respectively. CT and MRI offer the definite diagnosis of a lipoma, with MRI depicting better delineation and the ability to identify glandular elements of the tumor. Importantly, the development of sarcomatous change within the lipoma cannot be out ruled at imaging and requires a histologic specimen.

Good clinical and radiological response to BRAF inhibitor in patient with metastatic thin melanoma.

The authors herein report the case of a 32-year-old man with advancing metastatic malignant melanoma, who has progressed through all previous lines of therapy, presenting with ongoing respiratory tract symptoms of exertional shortness of breath and cough. CT restaging confirmed clinical findings of deteriorating pulmonary disease; histological review revealed V600E BRAF mutation. He was started on targeted biological therapy with BRAF inhibitor GSK2118436, and is having a good clinical and radiological response without significant lasting toxicity.

Postoperative magnetic resonance imaging characterization of slings for female stress urinary incontinence.

PURPOSE: The aim was to characterize different types of slings such as autologous rectus fascia (ARF), porcine dermis (PD) and tension-free vaginal tape (TVT) in the early postoperative period with regard to its visibility and location by using magnetic resonance imaging (MRI). MATERIALS AND METHODS: Between October 2003 and June 2007, total of 60 patients underwent MRI after a sling procedure. Thirty-six patients had ARF slings. Twelve patients had a PD sling and 12 had a TVT. All patients had pelvic MRI 6-8 hr postoperatively. Six patients in the ARF sling group had both preoperative and postoperative images at 6 hr and 3 months. MRI images were analyzed with regard to visibility and location. All data were collected prospectively. RESULTS: ARF slings were clearly visible in both T1W and T2W images. ARF appeared as low signal intensity area with surrounding high signal intensity due to fat attached to the rectus fascia in the MRI images obtained 6 hr after the procedure. Although the fatty component of the sling was diminished but was still visible on MRI scan 3 months postoperatively. On the other hand PD and TVT sling materials were not visible by MRI. Most of the ARF slings were located just below the bladder neck. CONCLUSIONS: The ARF sling is easily identifiable on MRI in the early postoperative period primarily because of the fat attached to the autologous rectus fascia. However, depiction of the PD and TVT slings in the early postoperative period is very poor.

Advanced and rapidly progressing head and neck cancer: good palliation following intralesional bleomycin.

The authors herein report the case of a 61-year-old man undergoing adjuvant therapy for locally advanced laryngeal cancer, who developed parastomal recurrence in his radiation field around his tracheotomy site, while he was undergoing radiation therapy, and compromised the secure placement of his tracheotomy tube and maintenance of his upper airway. MRI restaging and biopsy confirmed recurrence and progressive disease in his mediastinum. He underwent local therapy with intralesional bleomycin with good palliation, and ability to maintain the patency of his upper airway.

An anatomical study of the parasacral block using magnetic resonance imaging of healthy volunteers.

BACKGROUND: The parasacral approach to sciatic blockade is reported to be easy to learn and perform, with a high success rate and few complications. METHODS: Using magnetic resonance imaging, we evaluated the accuracy of a simulated needle (perpendicular to skin) in contacting the sacral plexus with this approach in 10 volunteers. Intrapelvic structures encountered during the simulated parasacral blocks were also recorded. RESULTS: The sacral plexus was contacted by the simulated needle in 4 of the 10 volunteers, and the sciatic nerve itself in one volunteer. The plexus was accurately located adjacent to a variety of visceral structures, including small bowel, blood vessels, and ovary. In the remaining five volunteers (in whom the plexus was not contacted on first needle pass), small bowel, rectum, blood vessels, seminal vesicles, and bony structures were encountered. Historically, when plexus is not encountered, readjustment of the needle insertion point more caudally has been recommended. We found that such an adjustment resulted in simulated perforation of intrapelvic organs or the perianal fossa. CONCLUSIONS: These findings question the reliability of the anatomical landmarks of the parasacral block and raise the possibility of frequent visceral puncture using this technique.

A technique for the computation of lower leg muscle volume from MRI images in the context of venous return.

A technique to automatically calculate the volume of a patient's calf muscle using MRI scans in the context of venous insufficiency is presented. Rather than giving a quantifiable measurement of volume, the technique provides a pixel count which can be used to compare the calf muscle volume of one leg of a patient against the other in the context of unilateral leg ulcers or to compare one patient's calf muscle volume against another patient. A custom MATLAB program reads the MRI scans (in the form of JPEG images) and determines the number of pixels (right and left limbs separately) that fall within a user defined gray-scale band, designated as being muscle. The output from the MATLAB program was compared with a manual counting method. The pixel counting algorithm was found to have an acceptable accuracy with results indicating a percentage difference from the manual method of between 2 and 9.5%.

A magnetic resonance imaging-based study of retropubic haematoma after sling procedures: preliminary findings.

OBJECTIVE: To determine, using magnetic resonance imaging (MRI), the incidence of retropubic haematoma and any associated clinically significant effects after a xenograft (porcine dermis) sling (XS) or the tension-free vaginal tape (TVT) procedure. PATIENTS AND METHODS: Between October 2003 and March 2004, 24 consecutive patients presenting with stress urinary incontinence (SUI) were enrolled in this prospective study; 12 each underwent an XS or TVT procedure. A vaginal balloon pack was used for only 3 h after XS and not after TVT. All patients had pelvic MRI 6-8 h after surgery. The primary outcome measure was the incidence and distribution of retropubic haematoma after each sling technique. Secondary outcome measures included the interval to the first three spontaneous voids, the bladder emptying efficiency of the first three voids, a visual analogue scale pain score at 24 h after surgery, and the short-term (6-month) cure rate for SUI. RESULTS: Overall, six (25%) patients (four XS and two TVT) developed a retropubic haematoma. Most commonly, they spread along the right paravesico-urethral space between the right half of the levator ani and the bladder neck. Patients with large haematomas took significantly longer to void (median 14.5 vs 6.0 h, P = 0.048). There was no difference in pain score in patients with or with no haematoma. None of the patients had clinically detectable haematomas in the suprapubic wound. All six patients with haematomas were cured or improved at the 6-month follow-up. CONCLUSIONS: MRI is a useful noninvasive method for detecting retropubic haematomas soon after surgery. There was a surprisingly high incidence of retropubic haematomas, especially after the XS procedure. Retropubic haematomas may influence postoperative voiding efficiency.

Axillary lymph node metastases: a statistical analysis of various parameters in MRI with USPIO.

PURPOSE: To assess the value of plain vs. iron oxide-enhanced MRI vs. the combined study (plain + postcontrast) based on qualitative and quantitative parameters of three pulse sequences. MATERIALS AND METHODS: Data from two sites were acquired using the same technique; therefore, this data could be pooled. T1W-SE, T2W-FSE, and 3D-PSIF were used before and 24-36 hours after MRI with ultra small particles of iron oxide (USPIO) was performed. A total of 52 lymph nodes (LNs) in nine patients (25 benign, 27 malignant) were evaluated by two readers who were visually and quantitatively blinded to the histology. Combinations of the following diagnostic parameters were compared using logistic regression analysis: the short-axis diameter of the LN, the signal distribution of the LN on postcontrast agent MRI (homogeneous or heterogeneous), and qualitatively and quantitatively determined signal changes of the LN following administration of contrast agent in the three evaluated sequences. RESULTS: Using pre- and postcontrast data, the optimized accuracy based on the statistically most significant parameters (LN diameter > 6 mm, visual assessment of signal change on T2W-SE) was 87% (81% sensitivity, 92% specificity). Precontrast data alone yielded 75% accuracy (63% sensitivity, 86% specificity). Postcontrast data alone yielded 75% accuracy (56% sensitivity, 96% specificity). CONCLUSION: Based on our results, USPIO-MRI improved the diagnosis of metastatic axillary LNs compared with precontrast MRI alone. Both pre- and postcontrast studies are needed. T1W-SE and T2W-PSIF did not yield significant additional information. This study may help to further improve the technique of USPIO imaging.