Limitations of computed tomography in the evaluation of acute abdominal trauma: a prospective comparison with diagnostic peritoneal lavage

There has been recent enthusiasm for computed tomography (CT) to supplant diagnostic peritoneal lavage (DPL) in the detection of abdominal injuries. We prospectively compared CT to DPL following acute blunt trauma or stab wound to the abdomen. Patients with hemodynamic instability or overt signs of intraperitoneal pathology underwent urgent laparotomy and were excluded from study. Those with indications for DPL had lavage catheter insertion via open technique and attempted aspiration for gross blood. This was followed by contrast CT of the abdomen with a Technicare 2010 scanner. Lavage fluid, when required, was then instilled, recovered, and analyzed. CT interpretations were made in a blind fashion by a single staff radiologist. Decision for laparotomy was based on clinical, DPL, and CT data. In blunt trauma (N = 65), DPL detected 5/5 (100%) injuries discovered at laparotomy and CT 2/5 (40%). Following stab wounds (N = 35), DPL was true positive in 7/7 (100%) and CT in 1/7 (14.3%), with one false positive CT leading to negative laparotomy and one false positive DPL which prompted unnecessary celiotomy. Overall, the sensitivity of DPL was 100% versus 25% for CT and specificity 98.9% for both DPL and CT. In particular, CT missed seven solid visceral (five liver, two spleen), five hollow visceral, one major vascular, and three diaphragmatic lesions requiring operative intervention. In our experience, CT demonstrated an alarming incidence of false-negative studies. Given the widespread variability of CT equipment and personnel we would argue strongly against the use of CT alone in the evaluation of acute abdominal trauma and continue to support DPL as the most accurate and reliable instrument of detection.     

Minilaparoscopy in the diagnosis of peritoneal tumor spread: prospective controlled comparison with computed tomography

Background Early diagnosis of peritoneal spread in malignant disease prevents unnecessary laparotomies. Minimally invasive laparoscopy with the patient under conscious sedation is a new, easily feasible diagnostic technique. This study compares prospective and controlled diagnostic minilaparoscopy with computed tomography (CT) scan for the diagnosis of peritoneal metastases.Methods In this study, 56 patients with malignant disease were prospectively investigated with diagnostic minilaparoscopy and CT scan.Results The study criteria were fulfilled by 54 patients. Minilaparoscopy detected peritoneal carcinosis in 28 of 54 cases, whereas CT detected the disease in 14 of 54 cases. For 36 patients, the diagnosis could be verified by histologic examination of peritoneal biopsies or laparotomy. In this group, minilaparoscopy detected peritoneal carcinosis in 25 of 36 cases, whereas CT detected the dispose in 12 of 36 cases.Conclusions Minilaparoscopy was more sensitive than CT in detecting peritoneal carcinosis (100% vs 47.8%; p < 0.01). Considering its low grade of invasiveness and superior sensitivity, minilaparoscopy should be regarded as the procedure of choice for the early detection of peritoneal carcinosis.     

Acute pyelonephritis: comparison of diagnosis with computed tomography and contrast-enhanced ultrasonography

OBJECTIVE

To assess the value of contrast‐enhanced ultrasonography (US) with the contrast pulse‐sequence (CPS) technique for detecting renal parenchymal changes in acute pyelonephritis (APN), compared with contrast‐enhanced computed tomography (CT) as the reference standard.

PATIENTS AND METHODS

We examined 100 patients (82 women, 18 men; mean age 30.2 years, range 18–67); children (those aged <18 years) were excluded from the study. All patients had clinical symptoms suggestive of APN. For the US a Sequoia 512 (Acuson, Mountain View, CA, USA) unit including Cadence^TM CPS technology, with a 6C2 probe, was used. A bolus of a 2.4‐mL US contrast agent SonoVue (Bracco, Milan, Italy) was injected. For CT a multislice 16‐row unit was used (Sensation 16, Siemens, Erlangen, Germany), at a table speed of 2.5 mm/s and a slice thickness of 3 mm; 100 mL of intravenous iodinated contrast agent (flow 3 mL/s) was injected.

RESULTS

On contrast CT, 84 patients (84%) had renal parenchymal changes suggestive of APN; on contrast US, 82 of the 84 (98%) showed renal parenchymal changes, and APN was correctly diagnosed. Seventy‐six patients (90%) had unilateral and eight (10%) had bilateral APN, and in two (2%) with APN the diagnosis could not be confirmed by US/CPS (false‐negative). No false‐positive findings were detected on US/CPS, which had a sensitivity of 98%, a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 89%.

CONCLUSION

CPS/US is accurate for detecting parenchymal changes in APN; it is very sensitive and specific, and allows small renal parenchymal changes to be detected with no radiation exposure.     

Indications for computed tomography in children with blunt abdominal trauma

This investigation was undertaken to identify clinical variables, alone or in combination, that could be used to assign children to high- and low-risk categories for intra-abdominal injury following blunt trauma. Six hundred consecutive children who were examined with computed tomography (CT) following blunt trauma were enrolled. Complete data sets were available on 375 children. Stepwise logistic regression was used to identify predictor variables for the presence of abdominal injury. There were 174 children with abdominal injury detected by CT. Of these, 95 were classified as having significant injury. Indicators associated with significantly higher risk of abdominal injury included the following: more than three clinical indications given (odds likelihood ratio [OLR] = 4.60, 95% confidence interval [95% Cl] = 2.29, 9.21, p less than 0.001); gross hematuria (OLR = 5.80, 95% Cl = 2.51, 13.4, p less than 0.001); lap belt injury (OLR = 12.2, 95% Cl = 2.22, 66.8, p less than 0.01); assault or abuse as the mechanism of injury (OLR = 5.08, 95% Cl = 1.07, 24.2, p less than 0.05); abdominal tenderness (OLR = 2.73, 95% Cl = 1.296, 5.82, p less than 0.01); and Trauma Score less than or equal to 12 (OLR = 2.27, 95% Cl = 1.006, 5.13, p less than 0.01). No child with asymptomatic hematuria (n = 56), regardless of grade or neurologic impairment in the absence of abdominal findings (n = 15), had an abnormal CT examination. These data are useful as an adjunct to clinical judgment in triage when the availability of CT equipment is limited or there are competing extra-abdominal injuries.     

Abdominopelvic computerized tomography and open peritoneal lavage in patients with blunt abdominal trauma: a prospective study

This prospective trial compares abdominopelvic computerized tomography and open peritoneal lavage in the diagnosis of blunt abdominal trauma. Fifteen patients (group 1) were evaluated by both methods. Another 15 patients (group 2) had only computerized tomography. Criteria for a "positive" scan were hemoperitoneum and evidence of solid organ injury. Criteria for "positive" lavage were a grossly bloody return, erythrocyte count greater than 20.0 X 10(9)/L and leukocyte count greater than 0.5 X 10(9)/L. At laparotomy, only injuries requiring repair or excision were considered "true positive". Patients who did not have laparotomy and had an uncomplicated clinical course were considered "true negative". With tomographic criteria alone for diagnosis there would have been one false-positive and three false-negative results, compared with three false positive and no false negatives for open peritoneal lavage alone. None of the three patients who had negative findings on laparotomy suffered any morbidity or died. Results of computerized tomography and open peritoneal lavage agreed in 8 of 15 patients (kappa value = 0.52), indicating a low level of agreement between the two. The authors believe that open peritoneal lavage remains the diagnostic procedure of choice in blunt abdominal trauma.     

Evaluation of a diagnostic protocol using screening diagnostic peritoneal lavage with selective use of abdominal computed tomography in blunt abdominal trauma.

BACKGROUND: The optimal method of evaluating blunt abdominal trauma remains controversial. A combination of a sensitive screening test, diagnostic peritoneal lavage (DPL), and a specific test, abdominal computed tomography (CT), may be a safe, efficient approach to adult blunt abdominal trauma. METHODS: A prospective cohort study compared a protocol using screening DPL followed by selective use of abdominal CT (DPL/abdominal CT) and the use of abdominal CT alone in the evaluation of hemodynamically stable, adult blunt trauma patients. RESULTS: One hundred sixty-seven adult blunt trauma patients were initially evaluated by DPL (n = 71) or abdominal CT (n = 96). Emergency department evaluation required less time in the DPL/abdominal CT group than in the abdominal CT alone group (41 minutes vs. 2.5 hours; p < 0.001). There were no missed injuries in the DPL/abdominal CT group versus seven missed injuries in the abdominal CT group (p = 0.02). There were no nontherapeutic celiotomies in either study group. CONCLUSION: Screening DPL, followed by abdominal CT if positive, is a safe, efficient method of evaluating adult blunt abdominal trauma that reduces the time required to evaluate the abdomen, does not result in increased nontherapeutic celiotomies, results in fewer missed injuries, and reduces the overall use of abdominal CT.     

A prospective study of 91 patients undergoing both computed tomography and peritoneal lavage following blunt abdominal trauma

Recent reports comparing computed tomography of the abdomen (CTA) and diagnostic peritoneal lavage (DPL) following trauma have been contradictory. A 10-month prospective study was conducted at our trauma center comparing both methods. Criteria for entry into the study included suspected blunt abdominal trauma without indication for immediate laparotomy, with either equivocal abdominal examination, diminished sensorium, or neurologic deficit. Ninety-one patients meeting these criteria underwent CTA followed by DPL. CTA was performed using both oral and intravenous contrast; DPL was performed by the open technique with RBC greater than 100,000 mm3 or WBC greater than 500 mm3 as criteria for a positive examination. CTA was interpreted initially by available radiology staff and residents and retrospectively reviewed by an experienced tomographer blind to DPL and surgical results. Twenty patients in whom either test was positive underwent laparotomy; all others were admitted for observation and/or extra-abdominal surgery. Laparotomy revealed 26 organs injured in the 20 patients explored at admission; none of the observed patients required delayed laparotomy. The results of CTA and DPL were compared to the findings at laparotomy or the clinical course of those not explored. The sensitivity, specificity, and accuracy for initial CTA were 60%, 100%, and 91%; for review CTA 85%, 100%, and 97%; for DPL 90%, 100%, and 98%. We conclude that: even with experienced examiners, CTA offers no diagnostic advantage over DPL in blunt trauma; because of relative costs, we do not recommend the routine application of CTA; CTA is a reliable alternative when circumstances prevent the performance of DPL.     

Evaluation of computed tomography and diagnostic peritoneal lavage in blunt abdominal trauma

Three hundred one hemodynamically stable patients with equivocal abdominal examinations following blunt abdominal trauma had a CT scan followed by DPL. Both studies were negative in 194 patients (71.6%) and positive in 51 patients (27.1%). Seven of the 51 patients (13.7%) had an additional significant injury at operation that was not seen on the CT scan. Nineteen patients had a negative CT scan, a positive DPL, and a significant injury confirmed at celiotomy. In this group of 19 patients, the CT failed to identify seven splenic, three hepatic, and three small bowel injuries. There were two complications attributed to DPL. Three patients had a false negative DPL. Diagnostic peritoneal lavage continues to be a reliable study (sensitivity--95.9%, specificity--99%, accuracy--98.2%). The CT scan is not as sensitive (sensitivity--74.3%, p less than 0.001; specificity--99.5%, accuracy--92.6%). It is concluded that selective use of both procedures is appropriate as long as one recognizes the inherent limitations of each.     

The role of computed tomography in blunt abdominal trauma in children

This study was performed in order to test the hypothesis that abdominal computed tomography (CT) can assist in the decision to perform laparotomy in children following blunt trauma to the abdomen. Three hundred forty children with blunt abdominal trauma underwent evaluation with CT. Abdominal injuries were detected in 84 children (25%). These included: 75 injuries to solid viscera in 60 patients (30 splenic, 29 hepatic, 13 renal, and three pancreatic); four injuries to hollow viscera (three small bowel transections, and one rupture of the urinary bladder); and 23 skeletal injuries (21 fractures of the pelvis, and two lumbar spine subluxations). Injury to solid viscera was categorized as minor in 32 (43%), moderate in 18 (24%), or severe in 25 (33%) according to an assessment of the percentage of parenchyma involved. Hemoperitoneum was detected in 42 patients, and characterized as small in 18 (43%), moderate in nine (21%), and large in 15 (36%). CT was useful in establishing the location and extent of injuries, and in detecting the presence of blood or air in the peritoneal cavity. However, the extent of injury to solid viscera detected on CT did not correlate with the need for laparotomy. Of 46 moderate to severe anatomic injuries of the liver, spleen or kidney, only five (9%) required surgical intervention because of persistent bleeding or infection. Although laparotomy occurred more frequently in the presence of a large hemoperitoneum, only 6/24 (25%) with moderate to large hemoperitoneum required surgical exploration. This analysis confirms the usefulness of CT for detection of location and extent of injury in pediatric blunt abdominal trauma.(ABSTRACT TRUNCATED AT 250 WORDS)     

Blunt abdominal trauma: a prospective study with selective peritoneal lavage.

To determine the effectiveness of clinical evaluation and peritoneal lavage in blunt abdominal trauma, a prospective study was undertaken in 315 consecutive patients suspected of having this injury. Conscious patients with obvious physical findings were operated on without peritoneal lavage, and a diagnostic accuracy of 96% was achieved. In patients with altered states of consciousness, peritoneal lavage was studied prospectively for equivocal physical findings. An overall accuracy of 97% was achieved in such patients by peritoneal lavage. Peritoneal lavage was helpful in reducing the rate of normal findings at laparotomy by 50% in patients with altered states of consciousness and equivocal physical findings. Patients with normal findings on peritoneal lavage and subsequent deterioration had normal findings at laparotomy, which points to the value of further evaluation in such patients before laparotomy is carried out. Mortality is ultimately determined by the severity of the injury, despite early and definitive diagnosis and aggressive management.     

Incidental findings on whole-body trauma computed tomography: Experience at a major trauma centre

IntroductionThe use of total-body computed tomography (CT) scanning in the evaluation of multiply injured patients is increasing, and their liberal use has stirred debate as to the added benefit relative to the risk of radiation exposure and inappropriate use of limited healthcare resources. Findings unrelated to the clinician's reasons for requesting the radiological examination are often uncovered due to the comprehensive nature of the evaluation at a trauma centre. However, some of these findings are outside the expertise of the trauma team who initially organised the scan and this may lead to uncertainty over who is best qualified to follow-up the incidental finding. We aim to evaluate the frequency of incidental findings on whole body trauma CT scans in a consecutive series of trauma admissions to our unit.Materials and methodsWe identified 104 consecutive major trauma patients who received a whole-body trauma CT (head, cervical spine, chest, abdomen and pelvis) from Jan 2013 to Dec 2013 in our unit (out of a total of 976 trauma admissions in the same year). Patient-specific information was extracted from computerised hospital databases containing admission and progress notes, radiological reports, operation notes and pathology reports.Results57 patients (54.8%) had incidental findings identified on the radiologist report, with a total of 114 individual incidental findings. 6 (5.8%) patients had potentially severe findings that required further diagnostic work up; 65 (62.5%) patients had diagnostic workup dependant on their symptoms, and 43 (41.3%) patients had incidental findings of minor concern which required no follow up.Discussion and conclusionsOur findings reflect the literature noting that incidental findings are increasingly common due to the central diagnostic role of CT imaging in trauma care, but also due to advances in imaging techniques and quality. In keeping with published literature, we note that increased age is associated with an increased incidence of “incidental findings” and this will continue to rise with the ageing population and the mandatory nature of trauma CTs.     

Clinical significance of isolated intraperitoneal fluid on computed tomography in pediatric blunt abdominal trauma

Purpose

The finding of isolated free intraperitoneal fluid (FIPF) on computed tomography of the abdomen (CTA) in children after blunt trauma is of unclear clinical significance and raises suspicion for a solid or hollow viscus injury. In our institution, pediatric blunt trauma patients presenting with isolated FIPF on CTA who are hemodynamically stable and have no peritoneal signs on initial physical examination (iPE) have been historically approached nonoperatively. We reviewed our level 1 trauma center experience with this subset of the trauma population and sought to (1) justify an initial nonoperative approach and (2) identify early predictors of the eventual need for surgical exploration.

Methods

Data on all trauma patients less than 14 years of age admitted to our hospital from 2001 to 2006 after Blunt Abdominal Trauma (BAT) whose screening CTA showed FIPF and no other radiographic signs of solid or hollow viscus injury were retrieved from the local trauma registry. Clinical progress, operative findings, and follow-up were obtained by hospital and office chart review, as well as telephone contact. Mechanism of injury (MOI); Injury Severity Score (ISS); Revised Trauma Score; Pediatric Trauma Score (PTS); the presence of abdominal tenderness or external signs of injury on iPE; and quantity, location, and density of the FIPF were statistically analyzed as possible early predictors of the eventual need for surgical exploration.

Results

A total of 670 children admitted to our institution after blunt trauma were evaluated with CTA during the time of enrollment. Isolated FIPF was found in 94 individuals (14%). Mean age was 9.7 (±SD 3.2) years; 52% were males. Motor vehicle crash was the most common MOI. Mean PTS was 10.6 (±SD 1.8). Mean ISS was 10.2 (±SD 7.2). Free intraperitoneal fluid was most commonly found in only one intraperitoneal region (93%). Most patients (97%) were discharged home without undergoing a surgical procedure. Three other patients developed peritonitis on serial physical examination and were surgically explored. Hollow viscus injuries were found in 2 of these individuals and treated with primary repair or segmental bowel resection. All surgical patients enjoyed a full recovery, with no postoperative complications. The presence of abdominal tenderness on iPE and the quantity of FIPF on initial CTA were the only studied variables to reach statistical significance as predictors of the eventual need for operative intervention. Follow-up after hospital discharge was obtained in 46.8% (44/94) and averaged 124.9 weeks.

Conclusion

To the best of our knowledge, this is the largest series of pediatric blunt trauma patients with isolated FIPF on CTA ever reported. Our findings justify an initial nonoperative approach for the management of these individuals. Abdominal tenderness on iPE and the quantity of FIPF on initial CTA were predictors of the eventual need for operative intervention.     

Noncontrast computed tomography in obstructive anuria: a prospective study

Objectives. To evaluate the role of noncontrast computed tomography (NCCT) in the determination of the cause of obstructive anuria and to compare its accuracy with that of the traditional methods of combined plain abdominal x-ray (KUB) and gray-scale abdominal ultrasonography (US).Methods. The study included 40 consecutive patients with obstructive anuria. In addition to the routine evaluation, which included history, clinical examination, biochemical profile, KUB, and US, all patients underwent NCCT. The study patients were tested against an age and sex-matched control group that included the normal contralateral kidneys of 57 consecutive patients who underwent KUB, US, and NCCT for acute flank pain during the same study period. The reference standard for the determination of the cause of obstruction was retrograde or antegrade ureterography with or without ureteroscopy or open surgery. The absence of obstruction in the control group was confirmed by nonequivocal normal intravenous urography of the side free of flank pain. Both NCCT and combined KUB and US were compared regarding the sensitivity, specificity, and overall accuracy.Results. The study group had 48 renal units, because obstruction was bilateral in 8 patients and of a solitary kidney in 32. Of the 42 renal units with calculus obstruction, the site of stone impaction was identified in all renal units by NCCT (sensitivity 100%) and in only 25 by combined KUB and US (sensitivity 59.5%)—a significant difference (P = 0.0001). Of the 6 renal units with noncalcular obstruction, both NCCT and US diagnosed the cause of obstruction in 3. The overall sensitivity of NCCT in the determination of the cause of obstructive anuria was 94% and that of combined KUB and US was 58%—a significant difference (P = 0.0001). The specificity of NCCT was not significantly different from that of combined KUB and US (96.5% versus 93%, respectively). The overall accuracy of NCCT was 95% and that of combined KUB and US was 77%—a significant difference (P = 0.0003).Conclusions. In patients with obstructive anuria, conventional KUB and US could not identify the cause of ureteral obstruction in about 40% of the patients. Under such conditions, NCCT can accurately provide the diagnosis, obviating the need of invasive and expensive diagnostic procedures.     

Compliance with evidence-based guidelines for computed tomography of children with head and abdominal trauma

Introduction

Recently, two large prospective clinical trials developed and validated prediction rules for children at very low risk for clinically important traumatic brain injuries (ciTBI) or abdominal injury for whom CT is unnecessary. Specific criteria/guidelines were identified which if met would obviate the need for CT scanning. The purpose of this study was to assess compliance at a level one pediatric center with these guidelines as a tool for quality improvement.

The management of blunt abdominal trauma patients with computed tomography scan findings of free peritoneal fluid and no evidence of solid organ injury

Modalities available for the diagnosis of blunt abdominal traumatic (BAT) injuries include focused abdominal sonography for trauma, diagnostic peritoneal lavage, and computed tomography (CT) of the abdomen/pelvis. Hollow viscous and/or mesenteric injury (HVI/MI) can still be challenging to diagnose. Specifically, there is debate as to the proper management of BAT when CT findings include free peritoneal fluid but no evidence of solid organ injury (SOI). Our objective was to determine the incidence of HVI/MI and to evaluate the management of BAT patients with CT findings of peritoneal fluid without evidence of SOI. An Institutional Review Board-approved retrospective chart review was conducted of all BAT patients with peritoneal fluid on CT admitted to Kern Medical Center from January 1, 2003 to July 31, 2004. A total of 2651 trauma admissions yielded 79 patients. Fourteen of these had no evidence of SOI. Nonoperative management was successful in only 2 of these 14, whereas 12 required an operation, with 11 being therapeutic. Trigger to operate and time from presentation to laparotomy was hypotension in three patients (164 minutes), signs of HVI/MI on CT in two patients (235 minutes), diaphragm injury on CT in one patient (95 minutes), and for peritoneal signs in six patients (508 minutes). In BAT patients with peritoneal fluid on CT without evidence of SOI, there should be a high suspicion of HVI/MI. Relying on increasing abdominal tenderness to trigger laparotomy can result in delayed treatment.     

Oral contrast with computed tomography in the evaluation of blunt abdominal trauma in children.

BACKGROUND: The use of oral contrast in evaluating children by computed tomography (CT) following blunt trauma is controversial. The aim of this study was to evaluate retrospectively the use of oral contrast with abdominal CT in children with suspected abdominal injury. METHODS: The medical records of 101 children who underwent CT for abdominal trauma between 1993 and 1997 were reviewed for data pertaining to the mechanism of injury, clinical findings and management. Scans were reviewed by a paediatric radiologist and criteria of intestinal injury on CT described by Cox and Kuhn were used: (1) extraluminal air or contrast material, (2) focal area of thickening of bowel wall and mesentery, and (3) free intraperitoneal fluid in the absence of solid organ injury. RESULTS: CT was performed within a median time of 2.4 (range 1-48) h after the injury. On 37 (62 per cent) of 60 scans in children who had oral contrast, the duodenum was not opacified after a mean delay of 30 min. Intestinal injury was suspected on CT in four children. In two children with CT evidence of intestinal injury (with/without oral contrast) rupture of the duodenojejunal flexure (n = 1) or ileal perforation (n = 1) was found at laparotomy. Two children had a false-positive scan, leading to negative laparotomy; one scan with oral contrast incorrectly suggested a duodenal leak and in another child CT without oral contrast showed thickening of bowel wall with free intraperitoneal fluid but no specific intestinal injury was identified at laparotomy. One patient had two negative CT scans (with and without oral contrast) and underwent laparotomy for clinical suspicion of bowel injury; rupture of the splenic flexure of the colon was found at laparotomy. CONCLUSION: CT is not reliable for diagnosing intestinal injuries and this is not improved by use of oral contrast. Omission of oral contrast was not associated with delay in the diagnosis of intestinal injury. Since intestinal injuries are uncommon in children, a prospective multicentre study would determine more precisely the role of the routine use of oral contrast.