MRI with DWI for the Detection of Posttreatment Head and Neck Squamous Cell Carcinoma: Why Morphologic MRI Criteria Matter.

BACKGROUND AND PURPOSE: Although diffusion-weighted imaging combined with morphologic MRI (DWIMRI) is used to detect posttreatment recurrent and second primary head and neck squamous cell carcinoma, the diagnostic criteria used so far have not been clarified. We hypothesized that precise MRI criteria based on signal intensity patterns on T2 and contrast-enhanced T1 complement DWI and therefore improve the diagnostic performance of DWIMRI. MATERIALS AND METHODS: We analyzed 1.5T MRI examinations of 100 consecutive patients treated with radiation therapy with or without additional surgery for head and neck squamous cell carcinoma. MRI examinations included morphologic sequences and DWI (b=0 and b=1000 s/mm2). Histology and follow-up served as the standard of reference. Two experienced readers, blinded to clinical/histologic/follow-up data, evaluated images according to clearly defined criteria for the diagnosis of recurrent head and neck squamous cell carcinoma/second primary head and neck squamous cell carcinoma occurring after treatment, post-radiation therapy inflammatory edema, and late fibrosis. DWI analysis included qualitative (visual) and quantitative evaluation with an ADC threshold. RESULTS: Recurrent head and neck squamous cell carcinoma/second primary head and neck squamous cell carcinoma occurring after treatment was present in 36 patients, whereas 64 patients had post-radiation therapy lesions only. The Cohen κ for differentiating tumor from post-radiation therapy lesions with MRI and qualitative DWIMRI was 0.822 and 0.881, respectively. Mean ADCmean in recurrent head and neck squamous cell carcinoma/second primary head and neck squamous cell carcinoma occurring after treatment (1.097 ± 0.295 × 10-3 mm2/s) was significantly lower (P < .05) than in post-radiation therapy inflammatory edema (1.754 ± 0.343 × 10-3 mm2/s); however, it was similar to that in late fibrosis (0.987 ± 0.264 × 10-3 mm2/s, P > .05). Although ADCs were similar in tumors and late fibrosis, morphologic MRI criteria facilitated distinction between the 2 conditions. The sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios (95% CI) of DWIMRI with ADCmean < 1.22 × 10-3 mm2/s and precise MRI criteria were 92.1% (83.5-100.0), 95.4% (90.3-100.0), 92.1% (83.5-100.0), 95.4% (90.2-100.0), 19.9 (6.58-60.5), and 0.08 (0.03-0.24), respectively, indicating a good diagnostic performance to rule in and rule out disease. CONCLUSIONS: Adding precise morphologic MRI criteria to quantitative DWI enables reproducible and accurate detection of recurrent head and neck squamous cell carcinoma/second primary head and neck squamous cell carcinoma occurring after treatment.

Imaging algorithms and CT protocols in trauma patients: survey of Swiss emergency centers.

OBJECTIVES: To identify imaging algorithms and indications, CT protocols, and radiation doses in polytrauma patients in Swiss trauma centres. METHODS: An online survey with multiple choice questions and free-text responses was sent to authorized level-I trauma centres in Switzerland. RESULTS: All centres responded and indicated that they have internal standardized imaging algorithms for polytrauma patients. Nine of 12 centres (75 %) perform whole-body CT (WBCT) after focused assessment with sonography for trauma (FAST) and conventional radiography; 3/12 (25 %) use WBCT for initial imaging. Indications for WBCT were similar across centres being based on trauma mechanisms, vital signs, and presence of multiple injuries. Seven of 12 centres (58 %) perform an arterial and venous phase of the abdomen in split-bolus technique. Six of 12 centres (50 %) use multiphase protocols of the head (n = 3) and abdomen (n = 4), whereas 6/12 (50 %) use single-phase protocols for WBCT. Arm position was on the patient`s body during scanning (3/12, 25 %), alongside the body (2/12, 17 %), above the head (2/12, 17 %), or was changed during scanning (5/12, 42 %). Radiation doses showed large variations across centres ranging from 1268-3988 mGy*cm (DLP) per WBCT. CONCLUSIONS: Imaging algorithms in polytrauma patients are standardized within, but vary across Swiss trauma centres, similar to the individual WBCT protocols, resulting in large variations in associated radiation doses. KEY POINTS: • Swiss trauma centres have internal standardized imaging algorithms for trauma patients • Whole-body CT is most commonly used for imaging of trauma patients • CT protocols and radiation doses vary greatly across Swiss trauma centres.

[Acute abdominal pain of the upper abdomen: which imaging to choose?]. / Douleurs abdominates aiguës hautes: quelle imagerie?

The aim of this article is to review the imaging modalities to be performed in patients with acute diffuse upper abdominal pain. Conventional radiography, ultrasound and computerized tomography (CT) are most often used in this setting. The choice of the initial imaging technique will depend from the localization of the pain and the probability of a particular pathology in the involved area.

[What imaging to choose for low abdominal pain?]. / Douleurs abdominales basses: quelle imagerie?

Nowadays, we need to counterbalance the excellent diagnostic yield of the abdominal CT Scan, with the significant risks of X irradiation. The Low Dose CT Scan allows confirmation of a diagnosis of appendicitis or nephrolithiasis with comparable precision and a much lower irradiation dose. In the case of appendicitis, the ultrasound is particularly useful, provided that the patient's BMI is <30. If there is suspicion of diverticulitis, the standard CT Scan remains the first line test. The Ultrasound is the first choice exam for a woman in childbearing age presenting with an acute abdominal pain.

CT scan-based modelling of anastomotic leak risk after colorectal surgery.

AIM: Prolonged ileus, low-grade fever and abdominal discomfort are common during the first week after colonic resection. Undiagnosed anastomotic leak carries a poor outcome and computed tomography (CT) scan is the best imaging tool for assessing postoperative abdominal complications. We used a CT scan-based model to quantify the risk of anastomotic leak after colorectal surgery. METHOD: A case-control analysis of 74 patients who underwent clinico-radiological evaluation after colorectal surgery for suspicion of anastomotic leak was undertaken and a multivariable analysis of risk factors for leak was performed. A logistic regression model was used to identify determinant variables and construct a predictive score. RESULTS: Out of 74 patients with a clinical suspicion of anastomotic leak, 17 (23%) had this complication confirmed following repeat laparotomy. In multivariate analysis, three variables were associated with anastomotic leak: (1) white blood cells count > 9 × 10(9) /l (OR = 14.8); (2) presence of ≥ 500 cm(3) of intra- abdominal fluid (OR = 13.4); and (3) pneumoperitoneum at the site of anastomosis (OR = 9.9). Each of these three parameters contributed one point to the risk score. The observed risk of leak was 0, 6, 31 and 100%, respectively, for patients with scores of 0, 1, 2 and 3. The area under the receiver operating characteristic curve for the score was 0.83 (0.72-0.94). CONCLUSION: This CT scan-based model seems clinically promising for objective quantification of the risk of a leak after colorectal surgery.

Assessment of recurrence and complications following uncomplicated diverticulitis.

BACKGROUND: The natural history of sigmoid diverticulitis has been inferred from population-based or retrospective studies. This study assessed the risk of a recurrent attack following the first episode of uncomplicated diverticulitis. METHODS: Patients admitted between January 2007 and December 2011 with a first episode of uncomplicated sigmoid diverticulitis confirmed on computed tomography were enrolled in this prospective study. After successful medical management of the first episode, follow-up was conducted through yearly telephone interviews. Cox proportional hazards regression was performed to model the impact of various parameters on eventual recurrences and complications. RESULTS: During a median follow-up of 24 (range 3-63) months, 46 (16·4 per cent) of 280 patients experienced a second episode of diverticulitis. Six patients (2·1 per cent) subsequently developed complicated diverticulitis and four (1·4 per cent) underwent emergency surgery for peritonitis. In multivariable analysis, a raised serum level of C-reactive protein (over 240 mg/l) during the first attack was associated with early recurrence (hazard ratio 1·75, 95 per cent confidence interval 1·04 to 2·94; P = 0·035). CONCLUSION: Uncomplicated sigmoid diverticulitis follows a benign course with few recurrences and little need for emergency surgery. REGISTRATION NUMBER: NCT01015378 (http://www.clinicaltrials.gov).

A clinical and radiological comparison of sigmoid diverticulitis episodes 1 and 2.

AIM: After an initial uncomplicated attack, sigmoid diverticulitis may recur, but the morphological characteristics of recurrent diverticulitis have not been investigated. We compared the clinical and radiological severity, the respective location and clinical outcome of the first two episodes of sigmoid diverticulitis. METHOD: We reviewed the charts of 60 patients [median age 61 (range 31-90) years] who were admitted initially for a first episode of uncomplicated left colonic diverticulitis, and who were eventually readmitted for a second episode, both being documented by abdominal computed tomography (CT) scan. RESULTS: The median delay between the two episodes was 19 (3-97) months. Six (10%) patients developed a second complicated episode of diverticulitis [Hinchey II (n = 2), CT-guided percutaneous drainage; Hinchey III (n = 3), emergency Hartmann's operation; colovesical fistula (n = 1), elective sigmoid resection]. Fifty-four (90%) patients were admitted for a second episode of uncomplicated diverticulitis. In this group, the duration of hospital stay [11 (4-22) vs 10 (1-39) days, P = 0.28], serum levels of C-reactive protein [131 (31-350) vs 112 (22-333) mm, P = 0.62] and CT scan-based severity score [3 (1-6) vs 3 (0-7) points, P = 0.07] were similar between the two episodes. In 19 out of 54 (35%) patients with simple recurrent diverticulitis, although disease severity was similar, the disease topography differed and recurrence involved another segment of the left colon. CONCLUSION: The majority of patients who develop recurrence do so in a similar mode and location. However, 10% develop complicated diverticulitis and in 35% of patients recurrent diverticulitis occurs at a different location.

[Testicular torsion: a tricky diagnosis]. / Torsion testiculaire: une urgence piège.

In common urological practice, testicular torsion is one of the most serious emergencies. Consequences can be devastating for the patient, both physically and psychologically. The primary care physician should be able to quickly identify the pathology and refer immediately the patient to a center with surgical facilities. Rapid diagnosis provides the best chances to save the patient's testicle, which may suffer irreversible damage as soon as 6 hours after the onset of the symptoms. History and clinical examination remain the cornerstones of the diagnosis, and are often sufficient to select patients who need surgical exploration. If time allows it, Doppler Ultrasound can often help distinguish torsion from other scrotal conditions, but cannot be considered as a 100% diagnostic tool.

Clinicoradiological score for predicting the risk of strangulated small bowel obstruction.

BACKGROUND: Intestinal ischaemia as a result of small bowel obstruction (SBO) requires prompt recognition and early intervention. A clinicoradiological score was sought to predict the risk of ischaemia in patients with SBO. METHODS: A clinico-radiological protocol for the assessment of patients presenting with SBO was used. A logistic regression model was applied to identify determinant variables and construct a clinical score that would predict ischaemia requiring resection. RESULTS: Of 233 consecutive patients with SBO, 138 required laparotomy of whom 45 underwent intestinal resection. In multivariable analysis, six variables correlated with small bowel resection and were given one point each towards the clinical score: history of pain lasting 4 days or more, guarding, C-reactive protein level at least 75 mg/l, leucocyte count 10 x 10(9)/l or greater, free intraperitoneal fluid volume at least 500 ml on computed tomography (CT) and reduction of CT small bowel wall contrast enhancement. The risk of intestinal ischaemia was 6 per cent in patients with a score of 1 or less, whereas 21 of 29 patients with a score of 3 or more underwent small bowel resection. A positive score of 3 or more had a sensitivity of 67.7 per cent and specificity 90.8 per cent; the area under the receiver operating characteristic curve was 0.87 (95 per cent confidence interval 0.79 to 0.95). CONCLUSION: By combining clinical, laboratory and radiological parameters, the clinical score allowed early identification of strangulated SBO.

Comparison of organ doses and image quality between CT and flat panel XperCT scans in wrist and inner ear examinations.

The aim of this study was to evaluate and compare organ doses delivered to patients in wrist and petrous bone examinations using a multislice spiral computed tomography (CT) and a C-arm cone-beam CT equipped with a flat-panel detector (XperCT). For this purpose, doses to the target organ, i.e. wrist or petrous bone, together with those to the most radiosensitive nearby organs, i.e. thyroid and eye lens, were measured and compared. Furthermore, image quality was compared for both imaging systems and different acquisition modes using a Catphan phantom. Results show that both systems guarantee adequate accuracy for diagnostic purposes for wrist and petrous bone examinations. Compared with the CT scanner, the XperCT system slightly reduces the dose to target organs and shortens the overall duration of the wrist examination. In addition, using the XperCT enables a reduction of the dose to the eye lens during head scans (skull base and ear examinations).

[Acute renal colic: which radiological exam in the GP daily practice?]. / Colique néphrétique au cabinet: quel bilan radiologique pour quel patient?

Nephrolithiasis is a common disease. Acute renal colic due to migration of stone is a frequent cause of admission in emergencies departements (ED). Diagnostic procedures in such centers are already well codified. This article discuss the diagnostic management and particularly the question of the radiological evaluation in patients presenting with renal colic to the general practitioner (GP). Because of the high risk of recurence and in order to identify patients with high stone burden, every patient presenting a first episode of renal colic should undergo radiological investigation. Considering sensitivity, irradiation rate, cost and diagnostic information, we recommend the (low-doses CT-SCAN as exam of choice for initial radiological evaluation of patient with renal colic.

Vascular invasion in pancreatic cancer: evaluation of endoscopic ultrasonography, computed tomography, ultrasonography, and angiography.

PRINCIPLES: Current methods for detecting vascular invasion in pancreatic cancer can be inaccurate, invasive, and expensive. The aim of this study is to assess the value of current imaging modalities in determining vascular invasion by pancreatic cancer. METHODS: The results of Endoscopic Ultrasonography (EUS), Computed Tomography (CT), Ultrasonography (US), and Angiography performed in 170 patients, suffering from pancreatic cancer, were retrospectively studied and correlated with intra-operative findings and surgical anatomopathological diagnosis after resection. We assessed sensitivity, specificity, positive and negative predictive values, and accuracy for detecting vascular invasion. RESULTS: EUS turned out to be the most reliable imaging technique for detecting vascular invasion in pancreatic cancer, with a sensitivity of 55%, specificity of 90%, positive predictive value of 61.1%, negative predictive value of 87.5%, and accuracy of 82.2%. CT results were 39.4%, 90%, 52%, 84.4%, and 79.1% for the respective categories, with however, better results with multislice CT. The US results were 3.7% for the sensitivity, 96.3% for the specificity, 25% for the positive predictive value, 75.2% for the negative predictive value, and 73.4% for the accuracy. For angiography, the sensitivity, the specificity, the positive predictive value, the negative predictive value, and the accuracy were 52.6%, 72.3%, 43.5%, 79.1%, and 66.7% respectively. CONCLUSION: In this study, EUS was the most valuable imaging modality in assessing vascular invasion (especially for venous invasion) for pancreatic cancer, with an accuracy of more than 80%. A further prospective study should be carried out to evaluate the combination of imaging modalities for the detection of vascular involvement, especially with multi-slice CT which almost reached the performances obtained by EUS.

Prospective study of 310 patients: can early CT predict the severity of acute pancreatitis?

BACKGROUND: This study was designed to determine the most important early CT parameters predictive of acute pancreatitis severity. METHODS: Three hundred and seventy-one consecutive patients with acute abdominal pain and hyperamylasemia were enrolled. Three hundred and ten of the 371 patients met our inclusion criteria. Acute pancreatitis severity was evaluated using the 1992 Atlanta criteria. Different CT parameters were reported from the admission abdominal CT by two radiologists blinded from any clinical parameter, but the patients' age and gender. These variables were fitted in a binary logistic regression model. RESULTS: Acute pancreatitis was mild in 80% cases, severe in 20% cases and lethal in 12.69% cases. The following CT parameters were significantly associated with the severity of acute pancreatitis: the objective size of the pancreas (P = 0.001), the peripancreatic fat abnormalities (P = 0.001) and the extent of necrosis (P = 0.007). Moreover, the age of the patient revealed itself a highly significant (P = 0.001) indicator of disease severity. The association of the four CT criteria eventually showed a sensitivity of 73% and a specificity of 81% to predict acute pancreatitis severity. CONCLUSION: Although these criteria correlated with disease severity, our study identified that morphological CT criteria cannot be used to triage patients with severe and mild acute pancreatitis.

Percutaneous CT scan-guided drainage vs. antibiotherapy alone for Hinchey II diverticulitis: a case-control study.

PURPOSE: CT-scan-guided percutaneous abscess drainage of Hinchey Stage II diverticulitis is considered the best initial approach to treat conservatively the abscess and to subsequently perform an elective sigmoidectomy. However, drainage is not always technically feasible, may expose the patient to additional morbidity, and has not been critically evaluated in this indication. This study was undertaken to compare the results of percutaneous drainage vs. antibiotic therapy alone in patients with Hinchey II diverticulitis. METHODS: This was a case-control study of all patients who presented in our institution with Hinchey Stage II diverticulitis between 1993 and 2005. Thirty-four patients underwent abscess drainage under CT-scan guidance (Group 1), and 32 patients were treated with antibiotic therapy alone (Group 2), in most cases because CT-scan-guided abscess drainage was considered technically unfeasible by the interventional radiology team. Initial conservative treatment was considered a failure when: 1) emergency surgery had to be performed, 2) signs of worsening sepsis developed, and 3) abscess recurred within four weeks of drainage. RESULTS: The median size of abscess was 6 (range, 3-18) cm in Group 1 and 4 (range, 3-10) cm in Group 2 (P = 0.002). Median duration of drainage was 8 (range, 1-18) days. Conservative treatment failed in 11 patients (33 percent) of Group 1, and in 6 patients (19 percent) of Group 2 (P = 0.26). Ten patients (29 percent) in Group 1 and five patients (16 percent) in Group 2 underwent emergency surgery (P = 0.24); there were four postoperative deaths (26.6 percent) in this subgroup. Twelve patients (35 percent) in Group 1 and 16 patients (50 percent) in Group 2 subsequently underwent an elective sigmoid resection (P = 0.31). In this subgroup of patients, there was neither anastomotic leakage nor postoperative death. CONCLUSIONS: Emergency surgery for Hinchey Stage II diverticulitis carries a high mortality rate and should be avoided. To achieve this, antibiotic therapy alone seems to be a safe alternative, whenever percutaneous drainage is technically difficult or hazardous. Actually, our data did not demonstrate any benefit of CT scan-guided percutaneous abscess drainage, suggesting that the role of interventional radiology techniques in this indication deserves further critical evaluation.

Results from percutaneous drainage of Hinchey stage II diverticulitis guided by computed tomography scan.

BACKGROUND: Percutaneous abscess drainage guided by computed tomography scan is considered the initial step in the management of patients presenting with Hinchey II diverticulitis. The rationale behind this approach is to manage the septic complication conservatively and to follow this later using elective sigmoidectomy with primary anastomosis. METHODS: The clinical outcomes for Hinchey II patients who underwent percutaneous abscess drainage in our institution were reviewed. Drainage was considered a failure when signs of continuing sepsis developed, abscess or fistula recurred within 4 weeks of drainage, and emergency surgical resection with or without a colostomy had to be performed. RESULTS: A total of 34 patients (17 men and 17 women; median age, 71 years; range, 34-90 years) were considered for analysis. The median abscess size was 6 cm (range, 3-18 cm), and the median duration of drainage was 8 days (range, 1-18 days). Drainage was considered successful for 23 patients (67%). The causes of failure for the remaining 11 patients included continuing sepsis (n = 5), abscess recurrence (n = 5), and fistula formation (n = 1). Ten patients who failed percutaneous abscess drainage underwent an emergency Hartmann procedure, with a median delay of 14 days (range, 1-65 days) between drainage and surgery. Three patients in this group (33%) died in the immediate postoperative period. Among the 23 patients successfully drained, 12 underwent elective sigmoid resection with a primary anastomosis. The median delay between drainage and surgery was 101 days (range, 40-420 days). In this group, there were no anastomotic leaks and no mortality. CONCLUSION: Drainage of Hinchey II diverticulitis guided by computed scan was successful in two-thirds of the cases, and 35% of the patients eventually underwent a safe elective sigmoid resection with primary anastomosis. By contrast, failure of percutaneous abscess drainage to control sepsis is associated with a high mortality rate when an emergency resection is performed. The current results demonstrate that percutaneous abscess drainage is an effective initial therapeutic approach for patients with Hinchey II diverticulitis, and that emergency surgery should be avoided whenever possible.

Diagnosis of occult scaphoid fracture with high-spatial-resolution sonography: a prospective blind study.

BACKGROUND: Evaluation of diagnostic accuracy of high-spatial-resolution sonography (HSR-S) in occult scaphoid fractures. PATIENTS AND METHODS: HSR-S was performed in 24 patients with clinically suspected fracture and normal radiographs. Three levels of clinical suspicion were considered (high, intermediate, and low). Three levels of sonographic suspicion were defined on the basis of cortical interruption, radiocarpal effusion, and scapho-trapezium-trapezoid effusion. Three positive criteria were interpreted as being highly indicative of fracture. Data from sonograms were compared with computed tomography (CT) scans. RESULTS: CT scanning demonstrated a fracture of the scaphoid in five patients. The global sensitivity of HSR-S for detection of occult scaphoid fracture was 100% and the specificity 79%. All patients with demonstrated occult fracture had a high sonography index of suspicion. A high sonography index of suspicion was correlated with 100% sensitivity, specificity, positive predictive value, and negative predictive value. CONCLUSION: HSR-S is a reliable, available, and cost-effective method in early diagnosis of occult fractures of the scaphoid. The presence of three defined criteria is required to assess the diagnosis.

Bleeding Meckel's diverticulum diagnosis: an unusual indication for computed tomography.

Despite the wide use of modern investigation techniques, the diagnosis of complications related to Meckel's diverticulum (MD) remains difficult. Arteriography is commonly indicated for acute bleeding, and radionuclide scans may help in identifying the site of intestinal hemorrhage. In contrast, computed tomography (CT) is usually considered little use in the diagnosis of bleeding MD. We present the case of a young patient with massive gastrointestinal hemorrhage, in whom the diagnosis of MD bleeding was preoperatively made with contrast-enhanced CT after two negatives arteriographies.

Helical computed tomography of bowel and mesenteric injuries.

BACKGROUND: The role of computed tomography in diagnosing hollow viscus injury after blunt abdominal trauma remains controversial, with previous studies reporting both high accuracy and poor results. This study was performed to determine the diagnostic accuracy of helical computed tomography in detecting bowel and mesenteric injuries after blunt abdominal trauma in a large cohort of patients. METHODS: One hundred fifty patients were admitted to our Level I trauma center over a 4-year period with computed tomographic (CT) scan or surgical diagnosis of bowel or mesenteric injury. CT scan findings were retrospectively graded as negative, nonsurgical, or surgical bowel or mesenteric injury. The CT scan diagnosis was then compared with surgical findings, which were also graded as negative, nonsurgical, or surgical. RESULTS: Computed tomography had an overall sensitivity of 94% in detecting bowel injury and 96% in detecting mesenteric injury. Surgical bowel cases were correctly differentiated in 64 of 74 cases (86%), and surgical mesenteric cases were correctly differentiated from nonsurgical in 57 of 76 cases (75%). CONCLUSION: Helical CT scanning is very accurate in detecting bowel and mesenteric injuries, as well as in determining the need for surgical exploration in bowel injuries. However, it is less accurate in predicting the need for surgical exploration in mesenteric injuries alone.

Successful treatment of a ruptured mycotic aneurysm of the ileocolic artery with transcatheter embolization and antibiotic therapy.

We report a case of mycotic aneurysm of the ileocolic artery due to Streptococcus bovis endocarditis and acute septicemia complicated by active hemorrhage, that was treated successfully with transcatheter embolization and subsequent intravenous antibiotic treatment. This case suggests that a mycotic aneurysm can be treated successfully by percutaneous embolization in an emergent situation (active bleeding, septicemia) even without previous antibiotic therapy.