A primer on rectal MRI in patients on watch-and-wait treatment for rectal cancer.

Total neoadjuvant treatment (TNT) for rectal cancer is becoming an accepted treatment paradigm and is changing the landscape of this disease, wherein up to 50% of patients who undergo TNT are able to avoid surgery. This places new demands on the radiologist in terms of interpreting degrees of response to treatment. This primer summarizes the Watch-and-Wait approach and the role of imaging, with illustrative "atlas-like" examples as an educational guide for radiologists.

Follow-up imaging of anal cancer after treatment.

Anal cancer treatment response assessment can be challenging with both magnetic resonance imaging (MRI) and clinical evaluation considered essential. MRI, in particular, has shown to be useful for the assessment of treatment response, the detection of recurrent disease in follow up and surveillance, and the evaluation of possible post-treatment complications as well as complications from the tumor itself. In this review, we focus on the role of imaging, mainly MRI, in anal cancer treatment response assessment.

Nodal drainage pathways in primary rectal cancer: anatomy of regional and distant nodal spread.

Nodal involvement is a significant prognostic factor in rectal cancer and difficult to assess preoperatively. An understanding of the patterns of nodal spread from different regions of the rectum can assist in this process and is essential for the purposes of surgical planning. In this article we define patterns of spread to mesenteric and pelvic sidewall nodal subgroups and discuss the importance of accurate anatomic localization of nodes for the purposes of staging and surgical planning.

MR staging of anal cancer: what the radiologist needs to know.

Anal canal cancer is a rare disease and squamous cell carcinoma is the most common histologic subtype. Traditionally, anal cancer is imaged with CT and PET/CT for purposes of TNM staging. With the increased popularity of MRI for rectal cancer evaluation, MRI has become increasingly utilized for local staging of anal cancer.

Diagnosis and Diagnostic Imaging of Anal Canal Cancer.

Anal canal cancer is an uncommon malignancy but one that is often curable with optimal therapy. Owing to its unique location, histology, risk factors, and usual presentation, a careful diagnostic approach is warranted. This approach includes an excellent history and physical examination, including digital rectal examination, laboratory data, and comprehensive imaging.

Variation in positron emission tomography use after colon cancer resection.

Purpose: Colon cancer surveillance guidelines do not routinely include positron emission tomography (PET) imaging; however, its use after surgical resection has been increasing. We evaluated the secular patterns of PET use after surgical resection of colon cancer among elderly patients and identified factors associated with its increasing use.

Patients And Methods: We used the SEER-linked Medicare database (July 2001 through December 2009) to establish a retrospective cohort of patients age ≥ 66 years who had undergone surgical resection for colon cancer.

Intraoperative sonography during open partial nephrectomy for renal cell cancer: does it alter surgical management?

Objective: The purpose of this study is to evaluate whether intraoperative ultrasound (IOUS) during open partial nephrectomy alters the surgical management for renal cell cancer (RCC).

Materials And Methods: One hundred ninety-eight consecutive patients undergoing IOUS during open partial nephrectomy for RCC were selected for retrospective review of clinical and imaging data. Patient age and sex, the local extent of the primary lesion, and the presence of additional lesions were recorded.

Optimization of MR imaging for pretreatment evaluation of patients with endometrial and cervical cancer.

Endometrial and cervical cancer are the most common gynecologic malignancies in the world. Accurate staging of cervical and endometrial cancer is essential to determine the correct treatment approach. The current International Federation of Gynecology and Obstetrics (FIGO) staging system does not include modern imaging modalities.

Pretreatment high-resolution rectal MRI and treatment response to neoadjuvant chemoradiation.

Background: Use of rectal MRI evaluation of patients with rectal cancer for primary tumor staging and for identification for poor prognostic features is increasing. MR imaging permits precise delineation of tumor anatomy and assessment of mesorectal tumor penetration and radial margin risk.

Objective: The aim of this study was to evaluate the ability of pretreatment rectal MRI to classify tumor response to neoadjuvant chemoradiation.

MR imaging for preoperative evaluation of primary rectal cancer: practical considerations.

High-resolution magnetic resonance (MR) imaging plays a pivotal role in the pretreatment assessment of primary rectal cancer. The success of this technique depends on obtaining good-quality high-resolution T2-weighted images of the primary tumor; the mesorectal fascia, peritoneal reflection, and other pelvic viscera; and superior rectal and pelvic sidewall lymph nodes. Although orthogonal axial high-resolution T2-weighted MR images are the cornerstone for the staging of primary rectal cancer, high-resolution sagittal and coronal images provide additional value, particularly in tumors that arise in a redundant tortuous rectum.

Quality initiatives: CT radiation dose reduction: how to implement change without sacrificing diagnostic quality.

The risks and benefits of using computed tomography (CT) as opposed to another imaging modality to accomplish a particular clinical goal should be weighed carefully. To accurately assess radiation risks and keep radiation doses as low as reasonably achievable, radiologists must be knowledgeable about the doses delivered during various types of CT studies performed at their institutions. The authors of this article propose a process improvement approach that includes the estimation of effective radiation dose levels, formulation of dose reduction goals, modification of acquisition protocols, assessment of effects on image quality, and implementation of changes necessary to ensure quality.

MR imaging in the triage of pregnant patients with acute abdominal and pelvic pain.

Purpose: To retrospectively assess the performance of MR imaging in the evaluation and triage of pregnant patients presenting with acute abdominal or pelvic pain.

Method And Materials: MRI studies of pregnant patients who were referred for acute abdominal pain between 2001 and 2007 were included. MR images were retrospectively reviewed and compared with surgical and pathologic findings and clinical follow-up data.

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia.

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia is an extremely rare pulmonary lesion, with only 39 cases reported in the literature. We report an additional case and review the literature. The patient is a 41-year-old man with a 5-year history of progressive dyspnea, cough, and wheezing.

Localization of appendix with MDCT and influence of findings on choice of appendectomy incision.

Objective: The purpose of this study was to show the relation between McBurney's point and the appendix in patients undergoing 3D MDCT and to investigate the effect of this information on a surgeon's choice of appendectomy incision.

Material And Methods: Among 142 adults undergoing consecutive MDCT studies, 100 patients (35 women, 65 men; mean age, 52.1 years) with an identifiable appendix on abdominopelvic MDCT examinations were selected for the study group.

Mimicks of pancreatic malignancy in patients with chronic pancreatitis: correlation of computed tomography imaging features with histopathologic findings.

Differentiation of chronic pancreatitis and pancreatic carcinoma can be a clinical and radiologic dilemma. Several patients with chronic pancreatitis can undergo unnecessary major abdominal surgery for benign lesions. This pictorial review illustrates the computed tomographic findings and histopathologic features of lesions mimicking pancreatic neoplasm in patients with chronic pancreatitis.

Medical qualification of a commercial spaceflight participant: not your average astronaut.

Background: Candidates for commercial spaceflight may be older than the typical astronaut and more likely to have medical problems that place them at risk during flight. Since the effects of microgravity on many medical conditions are unknown, physicians have little guidance when evaluating and certifying commercial spaceflight participants. This dynamic new era in space exploration may provide important data for evaluating medical conditions, creating appropriate medical standards, and optimizing treatment alternatives for long-duration spaceflight.

Revisiting MRI for appendix location during pregnancy.

Objective: The purpose of this study is to determine the location of the appendix in pregnant patients by MRI and to investigate the possibility of gradual upward displacement of the appendix during pregnancy.

Conclusion: The gradual upward displacement of the appendix during pregnancy was confirmed. MRI can be used for determination of the appendix localization in pregnant patients.

Rapid CT diagnosis of acute appendicitis with IV contrast material.

The purpose of this study was to determine the sensitivity and specificity of computed tomography (CT) without administration of oral contrast in confirming suspected acute appendicitis. One hundred seventy-three patient studies were retrieved by a computer-generated search for the word "appendicitis" in radiology reports. Patients presenting to the emergency department over an 8-month period were examined for acute abdominal pain or suspected acute appendicitis.

Magnetic resonance imaging of maternal diseases causing acute abdominal pain during pregnancy: a pictorial review.

Evaluation of acute abdominal pain in a pregnant patient is a clinical challenge. In these patients, magnetic resonance imaging (MRI) can allow a systematic cross-sectional evaluation of the entire abdomen and can provide clinically useful information in a short enough time for emergent diagnosis. This pictorial essay demonstrates MRI findings of various maternal diseases that can present as acute abdominal pain in pregnant patients.

Right-lower-quadrant pain and suspected appendicitis in pregnant women: evaluation with MR imaging--initial experience.

Purpose: To determine if there is a role for magnetic resonance (MR) imaging in evaluation of pregnant women with acute right-lower-quadrant pain in whom acute appendicitis is suspected.

Materials And Methods: Informed consent and institutional review board approval were obtained. Images obtained with a 1.

Traumatic diaphragmatic rupture: can oral contrast increase CT detectability?

Traumatic diaphragmatic rupture is a frequently missed diagnosis. We present a patient with traumatic diaphragmatic hernia. Diagnosis was suggested by a emergent computed tomography (CT) examination without oral contrast.

Alternative diagnoses to stone disease on unenhanced CT to investigate acute flank pain.

Acute flank pain is a common problem in emergency medicine. The most frequent cause is urolithiasis, but many other entities can cause the same clinical presentation. In many institutions unenhanced computed tomography (CT) of the abdomen is used in this setting.

Computerized tomographic colonography: performance evaluation in a retrospective multicenter setting.

Background & Aims: No multicenter study has been reported evaluating the performance and interobserver variability of computerized tomographic colonography. The aim of this study was to assess the accuracy of computerized tomographic colonography for detecting clinically important colorectal neoplasia (polyps >or=10 mm in diameter) in a multi-institutional study.

Methods: A retrospective study was developed from 341 patients who had computerized tomographic colonography and colonoscopy among 8 medical centers.