Can computed tomography scan findings predict "impending'' aneurysm rupture?

Several findings on computed tomography (CT) scans of intact aneurysms have been taken to suggest "imminent' or "impending' aneurysm rupture. Often these are identified incidentally in asymptomatic patients when an urgent operation was not planned and may even be ill advised. The authors evaluated whether these signs can truly predict short-term aneurysm rupture. A computerized medical archival system was reviewed from August 1994 to August 2004. Patients with aortic aneurysms and official CT scan reports of "impending rupture' were reviewed. CT films and reports were reviewed for aneurysm characteristics, while computerized medical records were reviewed for patient demographics, comorbidities, symptoms, documented subsequent rupture, and operative findings. Signs of "impending rupture' included the crescent sign, discontinuous circumaortic calcification, aortic bulges or blebs, aortic draping, and aortic wall irregularity. Rupture occurring within 2 weeks of the index CT was defined as supporting the "imminent' label. Forty-five patients with aortic aneurysms and CT stigmata of "impending rupture' were identified. Five patients with additional signs of suspicious leak and 1 with an infected previously repaired aneurysm were excluded. Of 39 intact aneurysms, 26 (67%) were infrarenal, 2 (5%) were suprarenal, and the remaining 11 (28%) were thoracoabdominal. The patient group had more women than expected (19/39, 49%) and larger aneurysms (mean diameter, 6.8 +/- 1.4 cm). Mean age was 74 years. Ten patients underwent elective repair within the first 2 weeks after the index CT scan (mean, 4 days), precluding adequate observation for early rupture. None had intraoperative signs of rupture. Early rupture: 2 of the 29 remaining patients ruptured within 72 hours of the CT scan, for a positive predictive value of 6.9%. One additional patient ruptured 7 months later after declining an early intervention. No Rupture: 26 patients were observed an average of 246 days (range, 14 days to 3 years) without evidence of rupture. Fourteen were repaired electively 2 weeks to 3 years after the index CT scan, and 12 never underwent repair, mostly because of severe associated comorbidities, and were observed a mean of 394 days without rupture. Although they should be taken seriously, CT signs of "impending rupture' alone are poor predictors of short-term aortic aneurysm rupture, and alternative terminology is needed until better predictors can be identified.     

Can a computed tomography scoring system predict the need for surgery in small-bowel obstruction?

BACKGROUND: Small-bowel obstruction (SBO) is a common dilemma faced by general surgeons. A timely and accurate diagnosis is crucial, based on history, physical examination, and radiographic studies. A computed tomography (CT) scan has become an increasingly common diagnostic modality. The aim of this study was to define a set of CT criteria that may help determine whether a patient would require operative intervention. METHODS: A retrospective chart review was performed over an 18-month period. Patients diagnosed with SBO or partial SBO (PSBO) who had a CT scan performed were included. CT scans were then reviewed independently by a staff radiologist blinded to the clinical outcome. A scoring system based on 7 radiographic criteria was then developed. Statistical analysis was performed on the data. RESULTS: From March 1, 2004, to August 30, 2005, 96 patients were found to have the diagnosis of SBO or PSBO and a documented CT scan. Seventy-four patients had undergone prior intra-abdominal procedures. Fifty-five percent were taken to the operating room (OR) over an average of 1.9 days (range 1-12 days). Seventy-nine percent of these patients went to the OR within the first 24 hours. Lysis of adhesions was performed in 38%, small bowel was resected in 47%, and incarcerated ventral hernias were found in 11%. Ischemic bowel was found in 11% of the cases. The CT scoring system was then correlated with the actual treatment. A score of 8 or higher predicted the need for surgery 75% of the time. When looking at the criteria individually, patients with a CT reading of complete obstruction, dilated small bowel, or free fluid were operated on 77%, 66%, and 65% of the time, respectively. CONCLUSION: A CT scoring system can successfully predict the need for surgery 75% of the time. Likewise, specific criteria, when present in combination, can predict the need for operative intervention in 79% of cases with SBO.     

Can clinical prediction tools predict the need for computed tomography in blunt abdominal? A systematic review

IntroductionBlunt abdominal trauma is a common reason for admission to the Emergency Department. Early detection of injuries is an important goal but is often not straightforward as physical examination alone is not a good predictor of serious injury. Computed tomography (CT) has become the primary method for assessing the stable trauma patient. It has high sensitivity and specificity but there remains concern regarding the long term consequences of high doses of radiation. Therefore an accurate and reliable method of assessing which patients are at higher risk of injury and hence require a CT would be clinically useful. We perform a systematic review to investigate the use of clinical prediction tools (CPTs) for the identification of abdominal injuries in patients suffering blunt trauma.Materials and methodsA literature search was performed using Medline, Embase, The Cochrane Library and NHS Evidence up to August 2014. English language, prospective and retrospective studies were included if they derived, validated or assessed a CPT, aimed at identifying intra-abdominal injuries or the need for intervention to treat an intra-abdominal after blunt trauma. Methodological quality was assessed using a 14 point scale. Performance was assessed predominantly by sensitivity.ResultsSeven relevant studies were identified. All studies were derivative studies and no CPT was validated in a separate study. There were large differences in the study design, composition of the CPTs, the outcomes analysed and the methodological quality of the included studies. Sensitivities ranged from 86 to 100%. The highest performing CPT had a lower limit of the 95% CI of 95.8% and was of high methodological quality (11 of 14). Had this rule been applied to the population then 25.1% of patients would have avoided a CT scan.ConclusionsSeven CPTs were identified of varying designs and methodological quality. All demonstrate relatively high sensitivity with some achieving very high sensitivity whilst still managing to reduce the number of CTs performed by a significant amount. Further studies are required to validate the results obtained by the highest performing CPTs before any firm recommendation can be used regarding their use in routine clinical practice.     

Can cervical spine computed tomography assist in detecting occult pneumothoraces?

IntroductionScreening CT often detects posttraumatic pneumothoraces that were not diagnosed on a preceding supine anteroposterior chest radiograph (occult pneumothoraces (OPTXs)). Because abdominal CT imaging misses OPTXs in the upper thorax, the objective of this study was to evaluate the utility of cervical spine (C-spine) CT screening for diagnosing OPTXs.MethodsA dual-institution (Foothills Medical Centre and Grady Memorial Hospital) retrospective review of consecutive OPTXs was performed. The accuracy of various CT screening protocols in detecting OPTXs was compared.ResultsOPTXs were detected in 75 patients. Patient demographics and injury characteristics were similar between centres (65% male; 97% blunt mechanism; 29% hemodynamically unstable; mean ISS = 27; mean length of stay = 22 days; mortality = 9%)(p > 0.05). Patients received either abdominal (41%) or thoraco-abdominal (59%) CT imaging. Most patients (89%) also underwent C-spine CT imaging. OPTXs were evident on thoracic CT in 100% (44/44), abdominal CT in 83% (62/75), and C-spine CT in 82% (55/67) of cases. All patients with OPTXs identified solely on thoracic CT (i.e. not abdominal) who also underwent imaging of their C-spine could have had their OTPXs diagnosed by using the pulmonary windows setting of their C-spine CT series. Combining C-spine and abdominal CT screening diagnosed all OPTXs (67/67) detected on thoracic CT, for patients who also underwent these investigations.ConclusionsOPTXs were evident on thoracic (and not abdominal) CT in 17% of severely injured patients. For patients who also underwent C-spine imaging, all OPTXs isolated to thoracic CT could be diagnosed by using the pulmonary windows setting of their C-spine CT imaging protocol. All OPTXs, regardless of intra-thoracic location, could also be detected by combining C-spine and abdominal CT screening.     

Can preoperative computed tomography of the chest predict completeness of the major pulmonary fissure at surgery?

Background

An incomplete major pulmonary fissure can make anatomic lung resection technically more difficult and may increase the risk of complications, such as prolonged postoperative air leak. The objective of this study was to determine if preoperative computed tomography (CT) of the chest could accurately predict the completeness of the major pulmonary fissure observed at the time of surgery.

Methods

From October 2008 to June 2009, patients at a single university institution were enrolled if they underwent surgery for a pulmonary nodule, mass or known cancer. At the time of surgery, completeness of the major pulmonary fissure was graded 1 if pulmonary lobes were entirely separate, 2 if the visceral cleft was complete with an exposed pulmonary artery at the base with some parenchyma fusion, 3 if the visceral cleft was only evident for part of the fissure without a visible pulmonary artery and 4 if the fissure was absent. The preoperative CT scan of each patient was graded by a single, blinded chest radiologist using the same scale. We used the Pearson χ² test with 2-tailed significance to test the independence of the operative and radiologic grading.

Results

In 48% (29 of 61) of patients, the radiologic and operative grading were the same. Of those graded differently, 94% (30 of 32) were within 1 grade. Despite this agreement, we observed no statistically significant correlation between the operative and radiologic grading (p = 0.24).

Conclusion

The major fissure can often be well-visualized on a preoperative CT scan, but preoperative CT cannot accurately predict the completeness of the major pulmonary fissure discovered at surgery.     

Can computed tomography in the protocol for renal colic be interpreted by urologists?

OBJECTIVE: To examine the ability of urologists to independently (with no radiology consultation) interpret non-contrast-enhanced spiral computed tomography (CT) in patients with acute renal colic. PATIENTS AND METHODS: One hundred consecutive patients presenting to the emergency department with suspected renal colic and evaluated with non-contrast spiral CT were retrospectively reviewed. The CT films of each patient were assessed separately by a first-year urology registrar and by a consultant urologist (neither of whom were subspecialized in uroradiology or endourology). The acute presentation details were provided to mimic the emergency situation. RESULTS: Ureteric calculi causing acute renal colic were evident in 54 patients. The consultant radiologist reported 51 ureteric calculi, and had a sensitivity, specificity and positive predictive value of 94.5%, 100% and 100%, respectively. The consultant urologist correctly identified 52 calculi, with sensitivity, specificity and positive predictive values of 96.3%, 82.7% and 86.7%. The urology registrar detected 51 stones with sensitivity, specificity and positive predictive values of 94.5%, 93.5% and 94.5%, respectively. CONCLUSION: Non-contrast spiral CT in patients with acute renal colic is an effective diagnostic tool which allows rapid and accurate evaluation of the urinary tract, thereby facilitating the acute management of patients with renal colic.     

Can conventional examinations contribute to the diagnostic power of unenhanced helical computed tomography in urolithiasis?

INTRODUCTION: To investigate whether ordinary tests used in urolithiasis can increase the diagnostic value of unenhanced helical computed tomography (HCT). MATERIALS AND METHODS: Of all patients admitted with acute flank pain, 137 without radiocontrast allergy, pregnancy and renal insufficiency were included in the study. After urinalysis (Ur) and ultrasonography (USG), HCT without a contrast agent was taken by 5-mm collimation, thereafter excretory urography (EU) was obtained. Confirmation of a stone was done by various tests and/or treatment methods. Statistically, the predictive values of HCT, USG, EU and Ur and their combinations were evaluated using the area under the receiver operating characteristic curve (AROC). RESULTS: The patients' mean age was 38 (range 4-72) years. Sensitivity values of HCT, USG, EU and Ur were 97, 69, 71 and 81%, respectively. Their specificity values were 96, 87, 91 and 65%, respectively. The widest AROC was found for HCT (97%). The best test combination was [HCT or USG] according to the AROC value (93%), but none of the AROC values of the test combinations was higher than that of HCT. However, 95% confidence intervals of the AROC values of these tests and their combinations overlapped. CONCLUSIONS: Because the HCT combinations with other tests improved the diagnostic value of HCT, they should be preferred in some individuals suspected of having urolithiasis. However, the most feasible single test meeting the all usage purposes was HCT in terms of the AROC value, and the combination was [HCT or USG] in which either HCT or USG was positive.     

Can assessment for obstructive sleep apnea help predict postadenotonsillectomy respiratory complications?

BACKGROUND: The aim of this study was to determine the frequency and type of respiratory complications after adenotonsillectomy in children. A second aim was to assess the ability of preoperative sleep studies to identify children at risk for respiratory complications. METHODS: Children referred for sleep studies between 1992 and 1998, who underwent adenotonsillectomy within 6 months of the preoperative study, were reviewed. The study focused on two variables: the obstructive apnea and hypopnea index and the oxygen saturation nadir. Medical charts were reviewed for postoperative respiratory complications. RESULTS: Three hundred forty-nine children were referred for sleep studies, and 163 met the inclusion criteria. Thirty-four children (21%) had postoperative respiratory complications requiring a medical intervention. Children experiencing respiratory complications were younger (aged < 2 yr; adjusted odds ratio, 4.3; 95% confidence interval, 1.7-11) and had an associated medical condition (odds ratio, 3; 95% confidence interval, 1.4-6.5). A preoperative obstructive apnea and hypopnea index of 5 or more events per hour increased the chance of postoperative respiratory complications (odds ratio, 7.2; 95% confidence interval, 2.7-19.3), as did a preoperative oxygen saturation nadir of 80% or less (odds ratio, 6.4; 95% confidence interval, 2.8-14.5). A preoperative oxygen saturation nadir of 80% or less had a likelihood ratio of 3.1, increasing the probability of postoperative respiratory complications from 20 to 50%. CONCLUSIONS: The data suggest, but do not prove, that preoperative nocturnal oximetry could be a useful preoperative test to identify children who are at increased risk for postoperative respiratory complications.     

Does pelvic hematoma on admission computed tomography predict active bleeding at angiography for pelvic fracture?

Pelvic angiography plays an increasing role in the management of pelvic fractures (PFs). Little has been written regarding the size of pelvic hematoma on admission computed tomography (CT) and how it relates to angiography results after PF. This is a retrospective review of trauma patients with PF who underwent an admission abdominal/pelvic CT scan and pelvic angiography from 2001 to 2003. CT pelvic hematoma was measured and classified as minimal or significant based on hematoma dimensions. Presence of a contrast blush on CT scan was also documented. Thirty-seven patients underwent an admission CT scan and went on to pelvic angiography. Of the 22 patients with significant pelvic hematoma, 73 per cent (n = 16) had bleeding at angiography. Fifteen patients had minimal pelvic hematoma, with 67 per cent (n = 10) showing active bleeding at angiography. In addition, five of six patients (83%) with no pelvic hematoma had active bleeding at angiography. Six patients had a blush on CT scan, with five of these (83%) having a positive angiogram. But, 22 of 31 (71%) patients with no blush on CT scan had bleeding at angiography. The absence of a pelvic hematoma or contrast blush should not alter indications for pelvic angiography, as they do not reliably exclude active pelvic bleeding.     

Do signs of abdominal wall injury on computed tomography predict intra-abdominal injury in trauma patients with a seatbelt sign?

BackgroundA seatbelt sign in patients with blunt abdominal injury is associated with both abdominal wall and intra-abdominal injuries. This study aimed to assess the association between signs of abdominal wall injury on computed tomography (CT) and rates of intra-abdominal injury in patients with a blunt abdominal injury and a clinical seatbelt sign.MethodsThis study includes hemodynamically stable trauma patients with blunt abdominal injury and a clinical seatbelt sign who were hospitalized in two regional trauma centers in Israel, during 2014–2019. All data were collected via the medical center's trauma registry in both centers.ResultsWe identified 123 stable blunt abdominal trauma patients with a seatbelt sign, of which 101 (82.1%) and 22 (17.9%) had a low-grade and high-grade abdominal wall injury according to CT findings, respectively. Laparotomy rates were significantly higher in patients with signs of high-grade abdominal wall injury (p<0.0001). No differences in the timing of laparotomy between low and high-grade injuries were found.ConclusionsIn stable patients with blunt abdominal trauma and a clinical seatbelt sign, the severity of abdominal wall injury, as represented by CT findings, may predict a need for surgical treatment.     

Can negative appendectomy rate be decreased by using spiral computed tomography without contrast material?

Approximately 15-20% of error in the diagnosis of acute appendicitis argues for new diagnostic methods. In recent years it has been proposed that Computed Tomography be used in the diagnosis of acute appendicitis with high sensitivity and specificity. In our study, the effect of Computed Tomography on the diagnosis of acute appendicitis and on negative appendectomy was investigated on patients with suspected acute appendicitis. In the last 18 months, spiral Computed Tomography without contrast material has been used for 65 patients. The history, physical findings, laboratory results and Computed Tomography images of patients were compared and the final decision to operate was always made by an attending surgeon. The results of Computed Tomography have been correlated with the reports of pathology and operation findings. Other patients who have not been operated on have been followed up clinically. Correlating Computed Tomography results with operation findings revealed; 42 true positive, 3 false positive, 17 true negative and 3 false negative results. The sensitivity and specificity of CT have been found to be 93.3% and 85% respectively. Forty-eight out of 65 patients have been operated on for acute appendicitis and the negative appendectomy rate has been calculated as 6.25%. As a consequence, it was thought that in the diagnosis of acute appendicitis the use of Computed Tomography could decrease the negative appendectomy rate when used together with clinical follow-up.