Fluid-filled bowel mimicking hemoperitoneum: a false-positive finding during sonographic evaluation for trauma

This case report describes a patient who presented to the Emergency Department (ED) after a high-speed motor vehicle crash (MVC), whose initial ultrasound examination was interpreted as being positive for fluid in Morison's pouch. Subsequent ultrasound examinations and computed tomography scans further delineated this finding to be fluid-filled bowel juxtaposed between the liver and right kidney. With greater implementation of ED ultrasound, it is important to identify entities that cause false-positive and false-negative examinations.

Intraperitoneal fluid in children: normal ultrasound findings depend on which scan head you use

BACKGROUND

The detection of small quantities of unsuspected free intraperitoneal fluid (IPF) at US examination in children has increased markedly in our department since linear high-frequency probes have been used routinely for gastrointestinal examinations. Its clinical significance is unknown. OBJECTIVE. This study attempted to evaluate the sonographic detection, quantification and location of IPF in an unselected paediatric population using both convex or sector scan heads and a linear US probe in all to compare the results obtained using different probes.

MATERIALS AND METHODS

We prospectively scanned 272 unselected consecutive patients using a 7- or 5-MHz multifrequency sector or convex scan head and a 7-MHz linear US probe. IPF was searched for and recorded as 0=none, 1=minimal, 2=small, 3=moderate and 4=large amounts in the cul-de-sac, Morison's pouch and between bowel loops. The patient's position on arrival, indication for the sonogram, clinical expectation of IPF and result of the US examination were recorded until 100 children (46 girls, 54 boys; age 3 days to 15 years) with IPF had been seen. Statistical analysis was done comparing all variables one by one, two by two and three by three.

RESULTS

Of the 100 children with IPF, its presence was expected in 7 and clinically explainable in 5 others. Nine of these had moderate-to-large amounts of IPF, seen well with all US scan heads. In the other 88 asymptomatic subjects, the detection of unsuspected IPF varied significantly with different probes. Fluid in the cul-de-sac was detected with similar frequency with all probes, whereas fluid between bowel loops was seen much more frequently with the linear probe ( P>0.0000). Position on arrival, age and sex had no influence.

CONCLUSIONS

Minimal and small amounts of IPF can be seen between bowel loops in up to 22% of normal children. In this location, it is often seen using a linear scan head only. In the cul-de-sac, a sector scan probe is equally as able to detect IPF as a linear probe. When scanning the bowel with a linear high-frequency US probe, small pockets of mobile anechoic IPF should be considered a normal finding.

[Ultrasound investigation and mini-invasive ultrasound-assisted technologies in diagnosis and treatment of extra-organ separate fluid formations in abdominal cavity]

The authors discuss the use of ultrasound-assisted percutaneous puncture and drainage for diagnosis and treatment of extraorganic separate fluid formations in abdominal cavity (abscess, limited non-infected fluid formation, hematoma with clotted blood), determination of their sizes and obtaining material for laboratory study. 307 patients with various extraorganic separate fluid in formations in abdominal cavity were examined. Ultrasonic symptoms of abscess were described in 54 patients, of limited non-infected fluid formation--in 234, of hematoma with clotted blood in 19 patients. 146 patients were cured conservatively, 75 patients underwent US-assisted puncture, 76--US-assisted drainage. Mean time of drainage was 14 days (ranged from 10 to 20). There were neither complications nor lethal outcomes. Ultrasound examination and US-assisted mini-invasive surgery permit to detect precisely the nature of fluid formation, to perform timely and low-traumatic treatment.

The effect of lavage on intraabdominal cell burden

BACKGROUND

Abdominal lavage is a common surgical practice, but few studies have been conducted to assess its efficacy at removing cells from the abdominal cavity, particularly during laparoscopic surgery.

METHODS

After three 12-mm trocars were inserted into six female 30-kg pigs at the umbilicus left and right iliac fossae, the abdomen was insufflated with carbon dioxide. The pelvis of each pigs was injected with 6 million radiolabeled LIM 1215 cells. Then the abdominal cavity was irrigated with either 500 ml 0.9% saline, 500 ml 10% betadine solution, or 1 L 0.9% saline. A maximum of 5 L of solution was used for each animal. The lavage fluid was suctioned into separate containers after each aliquot, and each container was measured for radioactivity.

RESULTS

Significantly greater numbers of cells were removed by lavage by the first to third lavage cycle; however, after four lavage cycles, relatively few cells were removed by each further cycle. No difference was observed between 500-ml and 1-L aliquots. Additionally, the mechanical efficacy of 0.9% saline and 10% betadine solution appeared similar.

CONCLUSION

These findings suggest that optimal lavage consists of four irrigation/suction cycles utilizing 500-ml aliquots.

The hand-held FAST: experience with hand-held trauma sonography in a level-I urban trauma center

AIMS

To describe the effectiveness of a portable hand-held ultrasound machine when used by clinicians in the early evaluation and resuscitation of trauma victims.

METHODS

The study was a prospective evaluation in a level-I urban trauma center. The focussed assessment with sonography for trauma is a specifically defined examination for free fluid known as the focused assessment with sonography for trauma (FAST) exam. Seventy-one patients had a hand-held FAST (HHFAST) examination performed with a Sonosite 180, 2.4 kg ultrasound machine. Sixty-seven examinations were immediately repeated with a Toshiba SSH 140A portable floor-based machine. This repeat scan (formal FAST or FFAST) was used as a comparison standard between the devices for study purposes. Four patients had a HHFAST only, all with positive result, two being taken for immediate laparotomy, and two having a follow-up computed tomographic (CT) scan. Patient follow-up from other imaging studies, operative intervention, and clinical outcomes were also compared to the performance of each device.

RESULTS

There were 58 victims of blunt, and 13 of penetrating abdominal trauma. One examination was indeterminate using both machines. The apparent HHFAST performance yielded; sensitivity, specificity, positive predictive value, negative predictable value, and accuracy (S, S, PPV, NPV, A) of 83, 100, 100, 98, 98%. Upon review, a CT scan finding and benign clinical course found the HHFAST diagnosis to be correct rather than the FFAST in one case. Considering the ultimate clinical course of the patients, yielded a (S, S, PPV, NPV, A) of 78, 100, 100, 97, and 97% for the HHFAST and 75, 98, 86, 97, and 96% for the FFAST. Statistically, there was no significant difference in the actual performance of the HHFAST compared to the FFAST in this clinical setting.

DISCUSSION

Hand-held portable sonography can simplify early and accurate performance of FAST exams in victims of abdominal trauma.

Isolated fluid in the cul-de-sac: how well does it predict ectopic pregnancy?

We examined the risk of ectopic pregnancy among patients with isolated abnormal cul-de-sac fluid at transvaginal ultrasound. We conducted a retrospective cohort study of all ED patients presenting January 1995 to August 1999 with abdominal pain or vaginal bleeding and a positive beta-hCG test. The risk of ectopic pregnancy in patients with a moderate volume of anechoic fluid was compared with those with either a large volume of anechoic fluid or any echogenic fluid. Ectopic pregnancy was diagnosed in 16/38: 42%(95% CI 26%-59%) of patients with isolated cul-de-sac fluid, 5/23: 22% (95% CI 7%-42%) of patients with moderate amount of anechoic fluid, and 11/15: 73% (95% CI 45%-92%) of patients with a large volume of fluid or any echogenic fluid. These differences were significant (P =.005). Patients with isolated abnormal cul-de-sac fluid are at moderate risk for ectopic pregnancy. The risk increases if the fluid is echogenic or the volume is large.

Accuracy of emergency department bedside ultrasonography

OBJECTIVES

To determine which focused ultrasound examinations can be interpreted accurately by emergency physicians who have limited training and experience. To determine whether image quality and/or the operator's level of confidence in the findings correlates with accurate scan interpretation.

METHODS

A prospective sample of consenting adult emergency department patients with the conditions was selected for study. Scans were performed by emergency physicians who had attended a 3-day focused ultrasound examinations instruction course. All scans were videotaped and subsequently reviewed by a radiologist. Accuracy was determined by comparing the emergency physicians scan interpretation with preselected gold standards. Chi-squared tests were employed to determine if the individual performing the scan, the type of scan, patient's body habitus, image quality and/or operator confidence were reliable predictors of accuracy.

RESULTS

Between September 1997 and January 1999, 221 scans were studied. Accuracy varied widely depending on the type of scan performed: aortic scans were 100% accurate whereas renal scans had 68% accuracy. On bivariate analyses, there was little variation in the various operators' levels of proficiency and accuracy of interpretation was not associated with patient body habitus, image quality or operator confidence.

CONCLUSIONS

Neophytes can accurately perform and interpret aortic scans; additional training and/or experience appear to be necessary to achieve proficiency in conducting most of the other scans studied. Inexperienced operators are unable to discern whether their scan interpretations will prove accurate.

Minimal pelvic fluid in blunt abdominal trauma in children: the significance of this sonographic finding

PURPOSE

The aim of this study was to evaluate the significance of the ultrasonographic finding of pelvic fluid after blunt abdominal trauma in children as a predictor of an abdominal organ injury.

METHODS

The clinical and imaging data of 183 children with blunt abdominal trauma were reviewed retrospectively. All children had an abdominal sonography as the primary screening study. The ultrasound results were divided into 3 groups: group A, normal examination; group B, pelvic fluid only; group C, peritoneal fluid outside the pelvis. The results of the initial ultrasound examinations were compared with the findings of the CT scan, or a second ultrasound examination or the clinical course during the hospitalization.

RESULTS

Group A included 87 children; group B, 57, and group C, 39. Four abdominal organ injuries were missed by the ultrasound examination. The sensitivity and specificity of the ultrasound examinations to predict organ injury in presence of peritoneal fluid outside the pelvis were, respectively, 89.5% and 96.6%; the positive and negative predictive value were 87.2% and 97.3%. No statistically significant difference was seen between group A and group B, whereas the presence of peritoneal fluid outside the pelvic cavity (group C) was associated strongly with an organ injury (P <.001).

CONCLUSIONS

A normal ultrasound examination or the presence of pelvic fluid are associated with a low probability of an organ injury. In the presence of peritoneal fluid outside the pelvis, the probability of an organ injury is very high.

Sonographic diagnosis of pelvic adhesions in patients after ovum pickup

OBJECTIVE

To evaluate the use of transvaginal sonography for the detection of pelvic adhesions by using clear free fluid in the pouch of Douglas found after ovum pickup.

METHODS

A prospective clinical study was performed in an infertility unit of an academic research facility. Sonography was performed in 50 women with infertility 3 days after ovum pickup, and the visceral peritoneum of the uterus, the ovaries, and the fallopian tubes was scanned for possible pelvic adhesions.

RESULTS

The serosal surfaces of the uterus, ovaries, and fallopian tubes were successfully observed for the presence of adhesions in 86%, 68%, and 20% of the patients, respectively. Improved visualization was associated with an increased amount of pelvic fluid for the uterus (P = .01) but not for the ovaries and fallopian tubes. The amount of fluid in the pelvis correlated with an increased number of retrieved oocytes (P = .07) and a decreased need for manual manipulation to achieve proper imaging of the uterus (P = .001).

CONCLUSION

Transvaginal sonography performed in the presence of fluid in the pelvis may show adhesions mainly attached to the uterus and ovaries. Assessment of possible mechanical factors is important in planning treatment of patients with infertility.

The UHP ultrasound protocol: a novel ultrasound approach to the empiric evaluation of the undifferentiated hypotensive patient

This report describes a novel sonographic protocol for the evaluation of the undifferentiated hypotensive patient. This protocol combines components of 3 sonographic applications: free fluid, cardiac, and abdominal aorta into a single protocol. We believe this protocol and its underlying principles should be a routine part of the empiric evaluation of the patient with undifferentiated hypotension or pulseless electrical activity.

Emergency department ultrasonography in the evaluation of hypotensive and normotensive children with blunt abdominal trauma

PURPOSE

The aim of this study was to evaluate the accuracy of emergency department (ED) ultrasound scan in identifying which children with blunt torso trauma have intraperitoneal fluid associated with intraabdominal injuries (IAI).

METHODS

The authors conducted a prospective, observational study of children (< 16 years old) with blunt trauma who presented to a level 1 trauma center over a 29-month period and underwent abdominal ultrasound scan while in the ED. Ultrasound examinations were ordered at the discretion of the trauma surgeons or ED physicians caring for the patients, performed by trained sonographers, and interpreted at the time of the ultrasound. Ultrasound examinations were interpreted solely for the presence or absence of intraperitoneal fluid. Hypotension was defined as > or = 1 standard deviation below the age-adjusted mean. Patients underwent follow-up to identify those with intraperitoneal fluid and IAI.

RESULTS

A total of 224 pediatric blunt trauma patients had ultrasound scan performed and were enrolled. Thirty-three patients had IAI with intraperitoneal fluid, and ultrasound scan was positive in 27. The accuracy of abdominal ultrasound for detecting intraperitoneal fluid associated with IAI was sensitivity, 82% (95% confidence interval [CI] 65% to 93%); specificity, 95% (95% CI 91% to 97%); positive predictive value, 73% (95% CI 56% to 86%); and negative predictive value, 97% (95% CI 93% to 99%). In the 13 patients who were hypotensive, ultrasound scan correctly identified intraperitoneal fluid in all 7 patients (sensitivity 100%) with IAI, and hemoperitoneum and was negative in all 6 patients (specificity 100%) who did not have hemoperitoneum. Nine patients had IAI without intraperitoneal fluid, and ultrasound scan result was negative for fluid in all 9.

CONCLUSIONS

ED abdominal ultrasound scan used solely for the detection of intraperitoneal fluid in pediatric blunt trauma patients has a modest accuracy. Ultrasonography has the best test performance in those children who are hypotensive and should be obtained early in the ED evaluation of these patients.

Operative versus nonoperative management of blunt abdominal trauma: Role of ultrasound-measured intraperitoneal fluid levels

This study's objective was to analyze whether the quantity of free intraperitoneal fluid on ultrasonography, alone or in combination with unstable vital signs, is sensitive in determining the need for laparotomy in patients presenting with blunt trauma. Adult patients who presented with blunt abdominal trauma to 2 level I trauma centers were enrolled. Combined intraperitoneal fluid levels (anechoic stripe) of 5 intraperitoneal areas were measured and defined as small (< 1.0 cm), moderate (> 1.0 cm, < 3.0 cm), or large (> 3.0 cm). Unstable vital signs were defined as pulse > 100 bpm or systolic blood pressure < 90 mmHg. Exploratory laparotomy or computed tomography scan confirmed hemoperitoneum. Of 270 patients entered into the study, ultrasound detected free intraperitoneal fluid in 33 patients. Of the 18 patients with a large fluid accumulation, 16 underwent exploratory laparotomy (89% sensitivity), and all 8 patients with unstable vital signs underwent exploratory laparotomy (100% sensitivity). Of the 10 patients with a moderate fluid accumulation, 6 underwent exploratory laparotomy (60% sensitivity), and 4 of the 6 patients with unstable vital signs underwent exploratory laparotomy (67% sensitivity). A large intraperitoneal fluid accumulation on ultrasonography in combination with unstable vital signs, is sensitive for determining the need for exploratory laparotomy in patients presenting with blunt trauma.

Absent peritoneal fluid on screening trauma ultrasonography in children: a prospective comparison with computed tomography

BACKGROUND

Although the accuracy of focused abdominal sonography for trauma (FAST) in adults has been demonstrated, results of this technique in children have been conflicting with few comparisons against computed tomography (CT), the imaging gold standard.

METHODS

A total of 160 hemodynamically stable pediatric trauma victims referred for abdominal CT initially underwent rapid screening sonography looking for free fluid. Both studies were interpreted in blinded fashion.

RESULTS

Forty-four of the 160 patients had an intraabdominal injury on CT, 24 (55%) of which had normal screening sonography. Fifteen of the 44 (34%) had no free fluid on either modality. Accuracy of sonography compared with CT was 76% with a negative predictive value 81%.

CONCLUSIONS

Sonography for free fluid alone is not reliable to exclude blunt intraabdominal injury in hemodynamically stable children given the considerable percentage of injured patients without free fluid. J Pediatr Surg 36:565-569.

Patterns of fluid accumulation on screening ultrasonography for blunt abdominal trauma: comparison with site of injury

The objectives of this study were to define where fluid accumulation is shown on screening ultrasonography after blunt abdominal trauma and to determine how fluid accumulation patterns are associated with the site of injury. From 1994 to 1998, 2,693 screening examinations for blunt abdominal trauma were performed, in which 7 regions were examined for fluid. On the basis of a preliminary analysis of patients with solitary injuries, all 194 patients with sonographically detected fluid were grouped by fluid accumulation pattern. Fluid patterns were compared with sites of injury. The patterns differed between hepatic and splenic injuries. Fluid in the left upper quadrant, in both upper quadrants, or diffusely distributed suggested splenic injury, whereas fluid in the right upper quadrant or the right upper quadrant and lower recesses suggested hepatic injury (P < .0001). Fluid accumulation was random after enteric injury. Patients with extraperitoneal injury had no fluid or had fluid focally at the injury site. The ability to predict the injury site on the basis of fluid patterns should expedite treatment of hemodynamically unstable patients with blunt abdominal trauma.

Quantification of fluid on screening ultrasonography for blunt abdominal trauma: a simple scoring system to predict severity of injury

A simple ultrasonographic method of fluid quantification, which counted the number of fluid recesses, was developed to predict the severity of injury after blunt abdominal trauma. From 1994 to 1998, 2,693 screening ultrasonographic examinations were performed for blunt abdominal trauma. Of this group, 2,499 patients had a fluid score of 0 (no fluid), and 1.4% had injuries (0.4% requiring surgery); 110 had a score of 1 (fluid in a single examined region), and 59% had injuries (13% requiring surgery); 33 had a score of 2, and 85% had injuries (36% requiring surgery); 30 had a score of 3, and 83% had injuries (63% requiring surgery); and 21 had a score of 4, and 95% had injuries (81 % requiring surgery). Patients with scores of 3 or greater had significantly higher rates of injury (P < .002) and injury requiring surgery (P < .0001) than patients with lower scores. The ability to predict injury severity on the basis of a simple ultrasonographic scoring system should expedite treatment of patients with severe trauma.

Abdominal ultrasound examination in pregnant blunt trauma patients

BACKGROUND

The ability of abdominal ultrasound to detect intraperitoneal fluid in the pregnant trauma patient has been questioned.

METHODS

Pregnant blunt trauma patients admitted to a Level I trauma center during an 8-year period were reviewed. Ultrasound examinations were used to detect intraperitoneal fluid and considered positive if such fluid was identified.

RESULTS

One hundred twenty-seven (61%) of 208 pregnant patients had abdominal ultrasound during initial evaluation in the emergency department. Seven patients had intra-abdominal injuries, and six had documented hemoperitoneum. Ultrasound identified intraperitoneal fluid in five of these six patients (sensitivity, 83%; 95% confidence interval, 36-100%). In the 120 patients without intra-abdominal injury, ultrasound was negative in 117 (specificity, 98%; 95% confidence interval, 93-100%). The three patients without intra-abdominal injury but with a positive ultrasound had the following: serous intraperitoneal fluid and no injuries at laparotomy (one) and uneventful clinical courses of observation (two).

CONCLUSION

The sensitivity and specificity of abdominal ultrasonography in pregnant trauma patients is similar to that seen in nonpregnant patients. Occasional false negatives occur and a negative initial examination should not be used as conclusive evidence that intra-abdominal injury is not present. Ultrasound has the advantages of no radiation exposure.

Ultrasound detection of free intraperitoneal fluid associated with hepatic and splenic injuries

BACKGROUND

The objective of this study was to compare the sensitivity and specificity of 5 abdominal views for detecting free intraperitoneal fluid in trauma patients later diagnosed with hepatic or splenic injuries.

METHODS

This retrospective study conducted over a 17-month period enrolled patients with trauma. A Focused Abdominal Sonogram for Trauma (FAST) examination was done using 5 abdominal views. Exploratory laparotomy or computed tomography (CT) confirmed the presence of intraperitoneal fluid and associated injuries. The sensitivity and specificity were determined.

RESULTS

Of the 245 study patients, 29 had injuries to the liver or spleen or both. The 5-view FAST examination's sensitivity for detecting free intraperitoneal fluid associated with hepatic, splenic, or combined injuries was 77%, 90%, and 100%, respectively. The sensitivity of the single Morison's pouch view in detecting free intraperitoneal fluid associated with hepatic, splenic, or combined injuries was 38%, 20%, and 67%, respectively.

CONCLUSION

For identifying free intraperitoneal fluid associated with hepatic or splenic injuries, no single view of the FAST examination could match the sensitivity provided by the 5-view technique.

Estimation of ascitic fluid volume using 99Tcm labelled macroaggregated albumin

We have assessed the usefulness of a radionuclide dilution method for estimation of ascitic fluid volume. 99Tc(m) macroaggregated albumin (10 MBq) was injected into the peritoneal fluid. Multiple samples were taken using a trocath peritoneal dialysis catheter over a 4-h period. Blood samples were taken at the same time and a 4-h urine collection was made during the study. At 4 h a controlled drainage of ascitic fluid, followed by suction drainage, was used and a total drained volume measured. For comparison, peritoneal volumes were measured from the radioactivity of peritoneal fluid activity samples using dilution techniques. The estimated peritoneal fluid volume using the radionuclide method was consistently higher than the drained volume. This was attributed to either a lack of uniform distribution of the activity in the peritoneal cavity by 4 h or early breakdown and absorption of activity from the peritoneal cavity. In two patients it was not possible to measure a volume due to poor distribution of the radionuclide in the peritoneal fluid. We found that in our group of patients the radionuclide dilution is of little value in estimating the peritoneal fluid volume.

Fluid collections detected by ultrasound following uncomplicated colorectal surgery

The aim of the study was to assess the incidence and site of intraperitoneal fluid collections following uncomplicated colorectal surgery and to identify factors relating to the presence of such collections. 38 patients (22 males) with a mean age of 67 years (range 38-85 years) undergoing uncomplicated colorectal procedures were studied prospectively. Patients underwent abdominal and pelvic ultrasound on Day 3 and Day 7 following surgery. The number, site and volume of collections were recorded. Ultrasound-detected fluid collections were present in 26% on Day 3 and 25% on Day 7 following laparotomy. The presence of a collection was not related to the amount of residual volume after peritoneal lavage with normal saline prior to operative closure, to intraoperative blood loss or to the presence of drains. The right upper quadrant was the commonest site of intraperitoneal collections. In the absence of additional clinical signs, the presence of such collections is not an indication for intervention.

Significance of minimal or no intraperitoneal fluid visible on CT scan associated with blunt liver and splenic injuries: a multicenter analysis

BACKGROUND

The use of ultrasound (U/S) for the evaluation of patients with blunt abdominal trauma is gaining increasing acceptance. Patients who would have undergone computed tomographic (CT) scan may now be evaluated solely with U/S. Solid organ injuries with minimal or no free fluid may be missed by surgeon sonographers.

OBJECTIVE

The purpose of this study was to describe the incidence and clinical importance of liver and splenic injuries with minimal or no free intraperitoneal fluid visible on CT scan. We hypothesized that these solid organ injuries occur infrequently and are of minor clinical significance.

METHODS

Patient records and CT scans were reviewed for the presence of and outcome associated with blunt liver and splenic injuries with minimal (<250 mL) or no free fluid detected by an attending radiologist. Data were collected from six major trauma centers during a 4-year period before the introduction of U/S and included demographics, grade of injury (American Association for the Surgery of Trauma scale), need for operative intervention, and outcome.

RESULTS

A total of 938 patients with liver and splenic injuries were identified. In this group, 11% of liver injuries and 12% of splenic injuries had no free fluid visible on CT scan and could be missed by diagnostic peritoneal lavage or U/S. Of the 938 patients, 267 (28%) met the inclusion criteria; 161 had injury to the spleen and 125 had injury to the liver. In the 267 patients studied, 97% of the injuries were managed nonoperatively. However, 8 patients (3%) required operative intervention for bleeding. Compared with the liver, the spleen was significantly more likely to bleed (p = 0.01), but the grade of splenic injury was not related to the risk for hemorrhage (p = 0.051).

CONCLUSION

Data from this study suggest that injuries to the liver or spleen with minimal or no intraperitoneal fluid visible on CT scan occur more frequently than predicted but usually are of minimal clinical significance. However, patients with splenic injuries may be missed by abdominal U/S. We found a 5% associated risk of bleeding. Therefore, abdominal U/S should not be used as the sole diagnostic modality in all stable patients at risk for blunt abdominal injury.

A prospective study of Tc-99m MIBI in the differential diagnosis of pelvic masses in female patients

PURPOSE

This study evaluated the feasibility of Tc-99m MIBI scintigraphy in the differential diagnosis of pelvic masses in female patients before operation.

METHODS

Seventy-one patients with pelvic masses were studied with planar imaging over the abdomen and pelvis 5, 15, 30, and 60 minutes after injection of 740 MBq (20 mCi) Tc-99m MIBI. The uptake of the masses was graded, and other abnormal signs, such as intestinal involvement, lymph node involvement, or peritoneal fluid collection, were also considered in image interpretation. An exploratory laparotomy was performed 3 days to 2 weeks after imaging. The scintigraphic diagnosis was compared with that of computed tomography (CT), CA-125 measurement, and pathologic analysis.

RESULTS

Forty-one of 46 pelvic masses with no activity were proved benign. Eighteen of 25 with a fixed, focal uptake were malignant. In 19 of 23 masses, intestinal activity noted within 30 minutes was caused by metastases. All three cases with lymph node involvement and six cases with ascites were confirmed malignant. Combining focal uptake with intestinal involvement correctly indicated 22 of 23 malignant conditions before operation, whereas negative scans identified 41 of 48 benign lesions. Four of seven false-positive lesions had a higher cellular component. The diagnostic performance of Tc-99m MIBI is better than that of CT and CA-125 tests, because CT had eight false-positive and three false-negative results, whereas CA-125 had 12 false-positive and 3 false-negative results, respectively.

CONCLUSIONS

Tc-99m MIBI is useful for differentiating benign and malignant pelvic masses in female patients. A fixed focal uptake or intestinal uptake of the radiotracer suggests malignancy, with diagnostic sensitivity, specificity, accuracy, and positive and negative predictive values of 95.6%, 85.4%, 88.7%, 75.9%, and 97.6%, respectively, in the current prospective study.

Transcatheter arterial embolization in blunt hepatic trauma

Patients with blunt hepatic injury can safely be managed nonoperatively if they show hemodynamic stability. Transcatheter arterial embolization (TAE) is a useful adjunct in the treatment of patients who show evidence of continued hemorrhage or who have pooling of contrast material on computed tomography (CT). In these patients, TAE may reduce transfusion requirements and allow healing of the injury without operation. Complications are uncommon and are usually managed nonoperatively.

Free fluid on abdominal computed tomography scan after blunt trauma does not mandate exploratory laparotomy in children

BACKGROUND/PURPOSE

The isolated finding of free intraperitoneal fluid on abdominal computed tomography (CT) scan after blunt trauma in adults is considered an indication for laparotomy by many trauma surgeons. The authors wished to determine if these guidelines are applicable to children.

METHODS

A retrospective chart review was conducted. The authors included all children (< or =12 years of age) sustaining blunt abdominal trauma who were admitted to our institution between January 1, 1994 and November 1, 1998.

RESULTS

There were 814 children admitted, and 437 had abdominal CT scans. Thirty-four studies showed free fluid associated with solid organ injuries, spine or pelvic fractures, or pneumoperitoneum, and were excluded. Thirty-two children had free fluid without associated injuries and formed the basis for the study. Five of these children underwent laparotomy based on the CT finding alone. The remaining 27 were observed with serial abdominal examinations and did not require surgical intervention. Only 1 of the 5 children who underwent surgery for the finding of isolated free fluid had a therapeutic laparotomy. In comparison, during the same period, 38 children underwent laparotomy after blunt injury based only on physical examination findings with a therapeutic laparotomy rate of 68%. The therapeutic laparotomy rate was significantly higher when the procedure was based solely on clinical examination as compared with the isolated finding or free fluid on the abdominal CT (26 of 38 v 1 of 5, P < .05).

CONCLUSION

In contrast to adults, finding isolated free fluid on abdominal CT scans in children after blunt trauma does not dictate immediate surgical exploration.

Acute hemoperitoneum in children: prevalence of low-attenuation fluid

BACKGROUND

Recent evidence indicates that acute hemoperitoneum may have lower than expected attenuation values at CT.

OBJECTIVE

To characterize the attenuation of acute hemoperitoneum at CT in children following blunt abdominal trauma and to assess the prevalence of low-attenuation fluid.

MATERIALS AND METHODS

The CT scans of 19 consecutive children with isolated hepatic or splenic injury and associated peritoneal fluid were retrospectively analyzed. The attenuation value of peritoneal fluid was assessed in all peritoneal spaces.

RESULTS

Fluid was noted in 53 peritoneal spaces (27 abdominal, 26 pelvic). Fluid attenuation ranged from 20 to 64 HU. The mean fluid attenuation in pelvic spaces (37.5 +/- 9.4 HU) was significantly lower than in abdominal spaces (444.9 +/- 10.2 HU) (P = 0.008). Fluid in 8/26 (31 %) pelvic spaces and 2/27 (7 %) abdominal spaces had attenuation values < or = 30 HU. Fluid surrounding the site of injury (perihepatic or perisplenic space) was significantly higher in attenuation than fluid at other sites (P < 0.001). There was no correlation between the mean attenuation value of peritoneal fluid in each patient and the admission hematocrit (r = -0.14, P = 0.55).

CONCLUSIONS

There is great variability in the attenuation of acute hemoperitoneum. Blood in pelvic spaces has significantly lower attenuation than blood in abdominal spaces. Hemoperitoneum in the pelvis has values of < or = 30 HU in approximately one-third of spaces. The attenuation of acute hemoperitoneum does not correlate with hematocrit.