Radiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

DOI: 10.1148/radiol.2312030027
This Article
Right arrow Abstract Freely available
Right arrow Figures Only
Right arrow Full Text (PDF)
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Múnera, F.
Right arrow Articles by Velez, G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Múnera, F.
Right arrow Articles by Velez, G.
(Radiology 2004;231:399-405.)
© RSNA, 2004

Emergency Radiology

Gunshot Wounds of Abdomen: Evaluation of Stable Patients with Triple-Contrast Helical CT1

Felipe Múnera, MD, Carlos Morales, MD, Jorge A. Soto, MD2, Hector I. Garcia, MD, MS, Tatiana Suarez, MD, Vanessa Garcia, MD, Mauricio Corrales, MD and Guillermo Velez, MD

1 From the Departments of Radiology (F.M., J.A.S., T.S., V.G., G.V.), Surgery, Division of Trauma Surgery (C.M., M.C.), and Epidemiology and Biostatistics (H.I.G.), Universidad de Antioquia, Hospital Universitario San Vicente de Paúl, Medellín, Colombia. From the 2002 RSNA scientific assembly. Received January 7, 2003; revision requested March 14; final revision received August 15; accepted September 29. Address correspondence to F.M., Department of Radiology, West Wing 279, University of Miami School of Medicine, Jackson Memorial Hospital/Ryder Trauma Center, 1611 NW 12th Ave, Miami, FL 33136 (e-mail: fmunera@med.miami.edu).


   ABSTRACT
TOP
 ABSTRACT
INTRODUCTION
 MATERIALS AND METHODS
RESULTS
 DISCUSSION
 REFERENCES
 
PURPOSE: To assess helical computed tomography (CT) with contrast material administered intravenously, orally, and rectally (triple contrast helical CT)) in the prospective evaluation of stable patients with abdominal gunshot wounds in whom there is no clinical indication for immediate exploratory laparotomy.

MATERIALS AND METHODS: The study was conducted for 19 months. All patients met the following inclusion criteria: age of 16 years or older, hemodynamic stability, no clinical signs of peritoneal irritation, and signed consent to participate. Patients with obvious indications for laparotomy, such as gastrointestinal bleeding or evisceration, were excluded from the study. Forty-seven patients fulfilled the criteria and underwent abdominal triple-contrast helical CT. CT findings were evaluated by one of four radiologists for evidence of peritoneal penetration and injury to solid organs or hollow viscera. Patients were followed up clinically for 13 weeks. CT findings were compared with those at surgery and/or clinical follow-up.

RESULTS: CT demonstrated abnormalities in 27 (57%) patients. Laparotomy was performed in 11 (23%) patients; 10 procedures were therapeutic and one was nontherapeutic. The remaining 20 patients had a negative CT scan. These patients were treated conservatively. One injury was missed at CT. For prediction of the need for laparotomy, sensitivity of CT was 96%; specificity, 95%; positive predictive value, 96%; negative predictive value, 95%; and accuracy, 96%.

CONCLUSION: In stable patients with gunshot wounds to the abdomen in whom there is no indication for immediate surgery, triple-contrast helical CT can help reduce the number of cases of unnecessary or nontherapeutic laparotomy (negative laparotomy) and can help identify patients with injuries that may be safely treated without surgery.

© RSNA, 2004

Index terms: Abdomen, CT, 70.12115 • Abdomen, injuries, 70.41 • Computed tomography (CT), clinical effectiveness, 70.12115 • Gunshot injuries, 70.41 • Trauma, 70.41


   INTRODUCTION
TOP
 ABSTRACT
 INTRODUCTION
MATERIALS AND METHODS
RESULTS
 DISCUSSION
 REFERENCES
 
Exploratory laparotomy traditionally has been considered mandatory for diagnosis and treatment of patients with gunshot wounds to the abdomen (1,2). This surgical approach is based on the following assumptions: Laparotomy is necessary to exclude intraabdominal injuries; diagnostic laparotomy is associated with little morbidity; and increased morbidity and mortality are associated with delayed treatment of injuries to the hollow viscus (3,4). The downside to this approach is that, in reality, it results in a high percentage of cases of unnecessary or nontherapeutic laparotomy (negative laparotomy) (5). Since the 1970s, selective treatment of these patients on the basis of clinical criteria has been attempted to decrease the number of cases of unnecessary laparotomy (6). More recently, there has been growing interest in selective treatment with the help of diagnostic procedures such as peritoneal lavage, laparoscopy, ultrasonography (US), and computed tomography (CT).

In the setting of blunt trauma, CT depicts injuries to solid viscera with high accuracy and helps guide clinicians in conservative nonsurgical treatment of many lesions (7). However, the role of CT in the diagnosis of injuries to the hollow viscus remains controversial, and researchers (8) in some studies report poor results. In other studies, investigators (9) who have used helical CT have reported a high accuracy for detection of bowel andmesenteric injuries. Helical CT has also been proposed for evaluation of victims of penetrating trauma to the neck, extremities, mediastinum, and abdomen (10–16). The purpose of our study was to assess helical CT with intravenously, orally, and rectally administered contrast material (triple-contrast helical CT) in the prospective evaluation of stable patients with abdominal gunshot wounds in whom there is no clinical indication for immediate exploratory laparotomy.


   MATERIALS AND METHODS
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
RESULTS
 DISCUSSION
 REFERENCES
 
Patients
The study was conducted prospectively for 19 months (August 1, 2000, to March 1, 2002). Our institutional review board approved the study, and informed consent was obtained from each patient or a close relative. The study included all patients 16 years or older who presented to our level 1 trauma center with abdominal gunshot wounds regardless of their anatomic location (anterior or posterior abdomen, flank, lower thorax, pelvis, or gluteal region). Other inclusion criteria for enrollment in this study were hemodynamic stability, defined as systolic blood pressure of 90 mm Hg or greater, and heart rate of 50–110 beats per minute at the time of admission or after administration of 2 L of crystalloid fluids; absence of clinical signs of peritoneal irritation; and no indication for immediate laparotomy, such as gastrointestinal bleeding, evisceration, or leakage of bile or gastrointestinal fluid from the wound. Patients who had superficial injuries that did not require further evaluation (adjacent entry and exit orifices and obvious subcutaneous trajectory or palpable subcutaneous bullet in proximity to the entry orifice), as well as those patients with a known allergy to iodinated contrast material, were excluded.

During the study period, 645 patients were admitted to our level 1 trauma center with gunshot injuries to the abdomen. Five hundred ninety-eight patients did not fulfill the study criteria and were excluded: patients who underwent surgery because of hemodynamic instability, those who had a clinical indication for exploratory laparotomy, or those who were observed clinically because they had obvious superficial injuries. The remaining 47 patients (43 male and four female patients) represent the patient population included in our study. Mean age was 23.5 years (range, 16–44 years). Mean age for male patients was 23.44 years (range, 16–44 years), and that for female patients was 24 years (range, 16–43 years). Differences between the age distributions according to sex were not statistically significant. Forty-six patients had single gunshot wounds, and one patient had multiple gunshot wounds.

Triple-Contrast Helical CT
All CT examinations were performed with a helical CT scanner (Prospeed SX; GE Medical Systems, Milwaukee, Wis), and images were acquired from the diaphragm to the femoral lesser trochanter. CT scans were obtained during the initial 4 hours after patient admission to the emergency room. Scanning parameters were as follows: 10-mm collimation, pitch of 1.5, 28–36-second exposure at one revolution of the x-ray tube per second, 200-mAs tube current, and 120-kVp tube voltage. We injected 100 mL of iopamidol (Iopamiron, 300 mg of iodine per milliliter; Schering, Erlangen, Germany) at a rate of 3.0 mL/sec by means of a power injector (Vistron CT Injection System; Medrad, Pittsburgh, Pa) through an 18-gauge catheter placed in an antecubital vein, with a scanning delay of 60 seconds. In addition, all patients received 800 mL of iodinated contrast material (Gastroview; Mallinckrodt Medical, St Louis, Mo) orally and 800 mL rectally. Contrast material was administered rectally by means of gravity flow through a Foley catheter, with the balloon inflated with sterile water. No complications resulted from the contrast material administration.

Helical CT Scan Interpretation
CT scans were interpreted prospectively by one of four radiologists (F.M., J.A.S., T.S., V.G.) who were fellowship-trained in body imaging or trauma radiology. Radiologists were informed of the mechanism of injury, physical examination findings, or clinical status of the patients. All examinations were considered adequate for diagnosis. Interpretation of CT scans was performed at an independent workstation (Advantage Windows; GE Medical Systems). CT scans were evaluated at standard soft-tissue window settings (level, 40 HU; width, 360 HU), as well as at lung window settings (level, –700 HU; width, 1,100 HU). The latter were used primarily for detection of pneumoperitoneum.

The radiologists evaluated the trajectory of the projectile; the abdominal wall for evidence of penetration of the peritoneum; and the peritoneal cavity for presence and location of free fluid, air, and injury to the solid organs, hollow viscera, and mesentery. Peritoneal penetration was diagnosed when CT scans showed an intraperitoneally located bullet or bullet fragment; evidence of intraperitoneal organ, mesenteric, or vascular injuries; pneumoperitoneum; or intraperitoneal free fluid. Injuries to solid organs were classified as laceration or subcapsular hematoma. Active extravasation of intravenous contrast material was defined as a focal fluid collection with attenuation values similar to those of the vascular structures. Presence of extraluminal oral or rectal contrast material or focal wall thickening greater than 5 mm was considered evidence of injury to the hollow viscus. Mesenteric injuries were diagnosed if there was interloop fluid, focal increase in attenuation of the mesentery, or mesenteric hematoma. CT scans that demonstrated any of these findings were considered positive, whereas scans that showed tangential abdominal wounds with an extraperitoneal trajectory were considered negative (nonpenetrating).

Findings at helical CT were disclosed to the trauma surgeons and were used in conjunction with the clinical findings and clinical status, as well as clinical follow-up, to determine patient care. Our institutional review board required this disclosure. The decision to perform exploratory laparotomy was made on the basis of the clinical evaluation and the results of the CT scan interpretation. Patients with positive CT results for injuries to hollow viscera underwent surgery, regardless of clinical status. For patients with positive CT results limited to the solid viscera and for patients with negative CT results, the decision to perform laparotomy was made by the trauma surgeon in charge of the patient’s care on the basis of clinical information. The clinical information included the patient’s clinical condition at admission, as well as during the observation period (24 hours for patients with negative CT results and 24–72 hours for patients with isolated injuries to solid viscera).

Standard of Reference
For patients who required laparotomy, surgical findings were used as the standard of reference for comparison of CT findings. For patients who did not require laparotomy immediately after admission, clinical outcome was used as the standard of reference. Patients with negative helical CT results were admitted for observation and discharged 24 hours later if their clinical status remained stable. After discharge, these patients were scheduled to be followed up clinically with physical examinations every 48 hours during the 1st week, every 7 days for 28 days, and then every other week for 60 days with telephone interviews. The total follow-up time for discharged patients with negative CT results was 13 weeks. These examinations and telephone contacts were conducted by one of two investigators (C.M., M.C.) to detect any complications related to the conservative treatment. For patients who remained asymptomatic after clinical follow-up, we assumed that no lesions were missed and that interpretations at triple-contrast helical CT were true-negative results.

Statistical Analysis
CT results were compared with surgical and clinical follow-up findings. We calculated the sensitivity, specificity, and positive and negative predictive values, as well as the 95% CIs and statistical power, for triple-contrast helical CT. All calculations and statistical tests were performed by using statistical software (Epidat, version 2.1; Pan American Health Organization–World Health Organization, Washington, DC).

For analysis of data, true-positive CT results were defined as all findings that were confirmed at surgery, as well as findings limited to the solid viscera or the mesentery in patients who were treated successfully without surgery during the complete period of observation and follow-up. True-negative CT results included findings in patients who did not require surgery and in whom CT results were either negative or showed no evidence of penetration and who were followed up as noted previously, as well as findings in patients with negative CT results who underwent laparotomy solely on the basis of clinical evaluation findings and in whom no injuries were found.

False-positive CT results included findings in patients with positive findings for injuries to hollow viscera who underwent exploratory surgery and in whom the injury diagnosed at CT was not confirmed at surgery. CT findings suggestive of injuries to the hollow viscera in patients who did not undergo surgery and who remained asymptomatic during the period of follow-up were also included. False-negative CT results included findings in patients with negative CT results who underwent surgery and in whom an injury that justified surgery was found. False-negative CT results also included findings in patients with negative findings at CT and clinical follow-up but in whom an injury was subsequently found.


   RESULTS
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
RESULTS
DISCUSSION
 REFERENCES
 
Seven (15%) of 47 patients had a trajectory of the projectile in the pelvic or gluteal regions, and 40 (85%) had a trajectory of the projectile in other anatomic areas (Table 1). CT depicted intraabdominal injuries in 27 (57%) patients (Table 2).


View this table:
[in this window]
[in a new window]

  		TABLE 1. Injury Distribution according to Anatomic Region in 47 Patients

 

View this table:
[in this window]
[in a new window]

  		TABLE 2. Injuries Observed at Triple-Contrast Helical CT and Comparison with Follow-up and Surgical Findings

 
Patients Who Underwent Laparotomy
Eleven patients underwent exploratory laparotomy; in nine of these patients, CT findings indicated injuries to hollow viscera. One additional patient underwent laparotomy as a result of a clinical decision made by the trauma team despite the CT finding of extraperitoneal trajectory, as the patient had fever, persistent abdominal pain, and tenderness 6 hours after the injury. No injuries were found during surgery. This case represents the only nontherapeutic laparotomy performed in this group. Another patient underwent exploratory laparotomy without clinical findings of peritoneal irritation or positive CT findings. The surgeon in charge of the patient’s care made this decision because general anesthesia was required for another procedure; a contusion was found in the wall of the cecum.

Patients Who Did Not Undergo Laparotomy
As a result of the information provided at helical CT, conservative or nonsurgical treatment was elected for 15 patients: 12 patients with injuries isolated to the liver, one patient with injuries to the liver and right kidney, and two patients with injuries to the spleen and kidney. These patients were treated nonsurgically and were followed up clinically (mean follow-up, 27 days; range, 14 days to 13 weeks); no laparotomy was required. Nine of these patients had right thoracoabdominal wounds with hemothorax and hepatic injuries. Thus, it was assumed that they had a wound to the diaphragm (Fig 1). They were treated with thoracostomy tube placement without abdominal surgical intervention. One of them developed a loculated hemothorax, which was drained at thoracoscopy. This group had an average hospital stay of 4.4 days (range, 1–12 days). These patients also underwent clinical follow-up (mean follow-up, 35 days; range, 18 days to 13 weeks), and none required surgical intervention. In summary, the information provided at CT helped the trauma surgeons avoid laparotomy in 35 (74%) cases.



View larger version (90K):
[in this window]
[in a new window]
[Download PPT slide]
  		Figure 1. Transverse CT scan obtained in a 23-year-old man with gunshot wound to right thoracoabdominal area shows injury to diaphragm, contusion (long straight arrow) of middle lobe, and laceration (arrowheads) of right dome of liver. Laceration appears as a wide low-attenuation defect that interrupts continuity of liver parenchyma. Associated right pleural effusion (short straight arrow) and thoracostomy tube (curved arrow) are seen.

 
Patients with True-Positive Results
Twelve patients had injuries isolated to the liver; one had injuries to the liver and right kidney and two had combined traumatic lesions of the lower pole of the spleen and the left kidney; nine patients had wounds of the hollow viscera, and two had penetrating wounds through the mesentery without injury to the solid or hollow viscera (Fig 2).



View larger version (99K):
[in this window]
[in a new window]
[Download PPT slide]
  		Figure 2. Transverse CT scan obtained in 20-year-old man with gunshot wound to left lower quadrant shows perforation of sigmoid colon and extraluminal contrast material (arrowheads) anterior to sigmoid colon. Note also large bullet fragment (arrow). Patient underwent exploratory surgery, and the injury was confirmed at laparotomy.

 
Patients with True-Negative Results
CT did not demonstrate any evidence of peritoneal penetration in 19 patients (Fig 3). Exploratory laparotomy was performed in one of these patients because of clinical indications, and no lesions were found. The other 18 patients had no complications during the clinical follow-up (mean follow-up, 15 days; range, 7 days to 13 weeks). Findings in these 19 patients were considered true-negative CT interpretations.



View larger version (120K):
[in this window]
[in a new window]
[Download PPT slide]
  		Figure 3. Transverse CT scan obtained in 21-year-old man with tangential gunshot wound to left flank clearly depicts extraperitoneal trajectory (long arrow) of bullet. Note laceration of abdominal wall that indicates location of exit wound (short arrow).

 
False-Positive CT Interpretation
In one patient, CT findings were interpreted as a laceration of the right hepatic lobe and a hematoma of the cecal wall, but laparotomy was not performed. The patient had no complications during the 4-week follow-up. Findings in this patient were considered a false-positive CT interpretation.

False-Negative CT Interpretation
One patient whose CT findings included right hemothorax, as well as injuries to the liver and the right diaphragm, underwent exploratory surgery for evaluation of an injury to the upper extremity. The trauma surgeon decided to perform exploratory laparotomy at the same time and found a 300-mL hemoperitoneum, a nonactively bleeding hepatic laceration, an injury to the right hemidiaphragm, and a contusion of the cecal wall without perforation. Since there is a risk of delayed perforation and leakage with such an injury, it was repaired. This patient’s postoperative course, with 7 days of hospitalization and 2 months of clinical follow-up, was uneventful. Findings in this patient were considered a false-negative CT interpretation, since no injury to the hollow viscus was suggested at prospective interpretation. However, at retrospective evaluation of CT scans, a small focal pericecal hematoma was evident (Fig 4).



View larger version (125K):
[in this window]
[in a new window]
[Download PPT slide]
  		Figure 4. Transverse CT scan obtained in 31-year-old man with tangential gunshot wound to right flank shows hematoma and fluid (straight arrow) located in fat adjacent to cecum. There is no associated extraluminal contrast material. Bullet (curved arrow) is located in posterior aspect of right psoas major muscle. Contrast material-filled appendix (arrowhead) is partially visualized. In this patient, a contusion of the cecal wall was found at exploratory laparotomy.

 
Statistical Evaluation
The diagnostic performance of helical CT for determination of the need for surgical intervention, with the corresponding 95% CIs, was analyzed and yielded these results: sensitivity, 96% (26 of 27 [95% CI: 79.1%, 99.8%]); specificity, 95% (19 of 20 [95% CI: 73%, 99.7%]); positive predictive value, 96% (26 of 27 [95% CI:79.1%, 99.8%]); negative predictive value, 95% (19 of 20 [95% CI: 73%, 99.7%]); and accuracy, 96% (45 of 47 [95% CI: 84.3%, 99.2%]). The statistical power was 95% (17). When the performance of the test for determination of conservative treatment of patients who had wounds to the solid viscera was analyzed separately, sensitivity, positive predictive value, and accuracy were 100%. For diagnosis of wounds of the hollow viscera or mesentery, performance analysis included these values: sensitivity, 92% (11 of 12 [95% CI: 59.7%, 99.6%]); specificity, 95% (19 of 20 [95% CI: 73%, 99.7%]); positive predictive value, 92% (11 of 12 [95% CI: 59.7%, 99.6%]); negative predictive value, 95% (19 of 20 [95% CI: 73%, 99.7%]); and accuracy, 96% (26 of 27 [95% CI: 77.8%, 96.9%]).


   DISCUSSION
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
RESULTS
 DISCUSSION
REFERENCES
 
All stable patients with injuries to the solid organs of the abdomen caused by blunt trauma are now considered candidates for nonsurgical treatment after their injuries have been evaluated with CT. However, these patients must remain in the care of experienced trauma surgeons who can recognize the presence of an associated injury to the hollow viscus or intervene if the nonsurgical approach fails (7,18–21). This alternative treatment is safe and reliable, even in those patients who have multiple associated trauma (22).

Before the 1970s and 1980s, the standard of care for abdominal gunshot wounds was mandatory exploratory celiotomy (1,23). Even as recently as 1990, McConnell and Trunkey (24) still advocated that all patients with gunshot wounds to the abdomen needed to undergo laparotomy. When this approach of mandatory celiotomy was followed, the frequency of negative or nontherapeutic laparotomy varied between 15% and 25% (25–27), with 20% morbidity (27). Knowledge gained from conservative or nonsurgical treatment of blunt and penetrating abdominal trauma that results from stab wounds has led to extension of this alternative treatment to select groups of victims of gunshot wounds. Some alternative diagnostic procedures, such as peritoneal lavage, laparoscopy, US, and CT, have been evaluated and have allowed this type of treatment to be refined.

Peritoneal lavage has high sensitivity but low specificity. Use of the cell count as a positive criterion for indication of when laparotomy should be performed is not uniform and has not been adjusted to the modern concept of nonsurgical treatment of wounds to the solid viscera (28). Laparoscopy is useful for diagnosis of peritoneal violation and wounds of the diaphragm, and in some patients, therapeutic procedures can be performed at the same time. The downside is that this is an invasive procedure that requires general anesthesia and that the evaluation of the retroperitoneum, as well of the hollow viscera, may be limited (29–31).

US is not as reliable for the evaluation of penetrating abdominal trauma as it is for the evaluation of blunt abdominal trauma. This observation may be because of the limitations in exclusion of gastrointestinal injuries and because the presence or absence of free intraperitoneal fluid alone is not an adequate parameter to indicate the need for exploratory laparotomy (11,32). Boulanger et al (33) proposed the routine use of US in patients who have gunshot wounds and in those who have injuries that involve sharp instruments that penetrate the torso to help guide the trauma surgeon in the decision process. However, when the results of US are negative, the presence of wounds of the hollow viscera or diaphragm are not excluded, and other diagnostic studies must be performed.

The first clinical studies in which the role of CT in the examination of patients with abdominal wounds caused by short stabbing weapons was evaluated showed that the method had high sensitivity and specificity for identification of wounds to the solid organs, as well as good performance for detection of retroperitoneal and peritoneal penetration. However, findings in these studies also suggested a lack of reliability for diagnosis of wounds to the intestine and diaphragm (34). The use of CT for evaluation of posterior penetrating wounds caused by short stabbing weapons has been emphasized (35–40).

In a prospective clinical study, Easter et al (36) compared CT with conventional diagnostic methods for evaluation of wounds to the back and flank. These researchers demonstrated that when CT was used there was no need for additional diagnostic studies. Soto et al (11) reported the use of serial US and triple-contrast helical CT in the evaluation of hemodynamically stable patients who had abdominal stab wounds and demonstrated that this approach could be followed to successfully guide trauma surgeons in conservative treatment. Researchers in several other studies (41–44) demonstrated the reliability of conservative or nonsurgical treatment of patients who had gunshot wounds to the solid viscera. In a retrospective analysis of 83 patients with abdominal gunshot wounds, with CT as the initial diagnostic test, Ginzburg et al (45) found 100% sensitivity, 54% specificity, and 71% accuracy, with better results for wounds to the flank. They proposed that if the question about the presence of peritoneal penetration persisted, then laparoscopy should be performed.

Chiu et al (46) reported findings of a prospective evaluation of triple-contrast helical CT as diagnostic support for performance of exploratory laparotomy and found 94% sensitivity, 95% specificity, 83% positive predictive value, and 98% negative predictive value. The CT readings were performed retrospectively in consensus by a group of experienced radiologists who did not know the patients’ clinical courses. In a larger study of patients with both penetrating stab and gunshot wounds from the same institution as was the study of Chiu et al (46), Shanmuganathan et al (10) also reported excellent results for the prediction of the need for laparotomy and exclusion of peritoneal violation in a prospective series with helical CT. In that study, the authors determined the patients’ outcomes by reviewing their medical records. Therefore, delay of presentation of injuries or complications might have gone undetected if patients sought care at a different institution.

In our study, we prospectively evaluated triple-contrast helical CT as a diagnostic test in patients who were hemodynamically stable in whom there was no indication for immediate laparotomy and who had abdominal gunshot wounds in any location, including the lower thorax, the anterior or posterior abdomen, the flank, the pelvis, and the gluteal region. Patient outcome was determined on the basis of the clinical follow-up findings. Our results showed a high positive predictive value when CT findings were correlated with surgical findings. CT was useful for demonstration of injuries to the hollow viscera that required laparotomy. CT also was helpful in detection of injuries isolated to solid organs, which were treated conservatively. In cases with findings interpreted as negative or in those in which conservative treatment was elected on the basis of the CT results, there was no further complication during follow-up, and these patients did not require further treatment or diagnostic studies.

The only false-negative interpretation in our study deserves further analysis. In the patient with this result, a contusion in the cecal wall was found at exploratory laparotomy. A slight increase in attenuation due to a small pericolonic hematoma was found in a retrospective analysis of the patient’s CT scans. There was also inadequate colonic distention with the contrast material. Because of the potential clinical consequences of missing an injury to the hollow viscus, when CT shows localized mesenteric or pericolonic hematomas, even without other evidence to suggest perforation, findings on CT scans should be interpreted as equivocal. In patients with these findings, evaluation should be performed with more definitive procedures such as laparoscopy or laparotomy to definitively exclude injuries to the hollow viscus.

Adequate colonic distention is also an essential factor to consider to avoid missing more subtle injuries. We have broadened the alternative of conservative or nonsurgical treatment of wounds to the right upper quadrant with associated liver injuries and right hemothorax caused by a single penetrating gunshot wound. Such wounds could lead to the assumption of a corresponding injury to the diaphragm, with no development of posttraumatic complications or hernias during an average 45-day follow-up. This assumption is based on the close relationship between the diaphragm and the liver, and this relationship does not allow hernia of the hollow viscera. Although the need for surgical repair of all right-sided injuries to the diaphragm remains controversial among trauma surgeons, our results and those of other investigators suggest that there might be a benign outcome for this type of injury. However, a longer follow-up period is required. Since most of our patients with injuries to the diaphragm did not undergo thoracoscopy or surgery for correlation of findings, we may have underestimated or overestimated the number of injuries to the diaphragm. Additional studies are required to establish the role of helical CT, compared with conventional invasive diagnostic methods such as thoracoscopy or laparotomy, in the evaluation of patients with gunshot injuries to the diaphragm.

In our study, imaging support for clinical judgment helped trauma surgeons avoid laparotomy in 35 (74%) cases, and only one nontherapeutic laparotomy (2%) was performed. CT was seen as an aid to clinical judgment within such a decision-making scenario.

Our results suggest that triple-contrast helical CT provides very important adjunctive information to help guide experienced trauma surgeons in the selective treatment of hemodynamically stable patients who have gunshot wounds to the abdomen and in whom there is no indication for immediate laparotomy.


   FOOTNOTES
 
2 Current address: Department of Radiology, Boston Medical Center, Mass. Back

Author contributions: Guarantor of integrity of entire study, F.M.; study concepts and design, F.M., C.M., H.I.G., J.A.S.; literature research, F.M., C.M., T.S., V.G., M.C.; clinical studies, F.M., J.A.S., T.S.; data acquisition, F.M., C.M., T.S., V.G., M.C., G.V.; data analysis/interpretation, H.I.G., C.M., F.M.; statistical analysis, H.I.G., C.M.; manuscript preparation, F.M., C.M.; manuscript definition of intellectual content, editing, revision/review, and final version approval, F.M., C.M., J.A.S.


   REFERENCES
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
RESULTS
 DISCUSSION
 REFERENCES
 

  1. Moore EE, Moore JB, Van Duzer-Moore S, Thompson JS. Mandatory laparotomy for gunshot wounds penetrating the abdomen. Am J Surg 1980; 140:847-851.[CrossRef][Medline]
  2. McCarthy MC, Lowdermilk GA, Canal DF, Broadie TA. Prediction of injury caused by penetrating wounds to the abdomen, flank and back. Arch Surg 1991; 126:962-965.[Abstract]
  3. Nance ML, Nance FC. It is time we told the emperor about his clothes. J Trauma 1996; 40:185-186.[Medline]
  4. Moore JB, Moore EE, Thompson JS. Abdominal injuries associated with penetrating trauma in the lower chest. Am J Surg 1980; 140:724-730.[CrossRef][Medline]
  5. Weigelt JA, Kingman RG. Complications of negative laparotomy for trauma. Am J Surg 1988; 156:544-547.[Medline]
  6. Ryzoff RI, Shaftan GW, Herbsman H. Selective conservatism in penetrating abdominal trauma. Surgery 1966; 59:650-653.[Medline]
  7. Knudson MM, Maull KI. Non-operative management of solid organ injuries: past, present, and future. Surg Clin North Am 1999; 79:1357-1371.[CrossRef][Medline]
  8. Sherck JP, Oakes DD. Intestinal Injuries missed by computed tomography. J Trauma 1990; 30:1-7.[Medline]
  9. Killeen KL, Shanmuganathan K, Poletti PA, Cooper C, Mirvis SE. Helical computed tomography of bowel and mesenteric injuries. J Trauma 2001; 51:26-36.[Medline]
  10. Shanmuganathan K, Mirvis SE, Chiu WC, Killeen KL, Scalea TM. Triple-contrast helical CT in penetrating torso trauma: a prospective study to determine peritoneal violation and the need for laparotomy. AJR Am J Roentgenol 2001; 177:1247-1250.[Abstract/Free Full Text]
  11. Soto JA, Morales C, Múnera F, Sanabria A, Guevara JM, Suarez T. Penetrating stab wounds to the abdomen: use of serial US and contrast-enhanced CT in stable patients. Radiology 2001; 220:365-371.[Abstract/Free Full Text]
  12. Múnera F, Soto JA, Palacio D, Velez SM, Medina E. Diagnosis of arterial injuries caused by penetrating trauma to the neck: comparison of helical CT angiography and conventional angiography. Radiology 2000; 216:356-362.[Abstract/Free Full Text]
  13. Múnera F, Soto JA, Palacio D, et al. Penetrating neck injuries: helical CT angiography for initial evaluation. Radiology 2002; 224:366-372.[Abstract/Free Full Text]
  14. Leblang SD, Nuñez DB, Rivas LA, Falcone S, Pogson SE. Helical computed tomographic angiography in penetrating neck trauma. Emerg Radiol 1997; 4:200-206.[CrossRef]
  15. Grossman MD, May AK, Schwab CW, et al. Determining anatomic injury with computed tomography in selected torso gunshot wounds. J Trauma 1998; 45:446-456.[Medline]
  16. Soto JA, Múnera F, Morales C, et al. Focal arterial injuries of the proximal extremities: helical CT arteriography as the initial method of diagnosis. Radiology 2001; 218:188-194.[Abstract/Free Full Text]
  17. Donner A, Eliasziw M. A goodness-of-fit approach to inference procedures for the kappa statistic: confidence interval construction, significance testing and sample size estimation. Stat Med 1992; 11:1511-1519.[Medline]
  18. Livingston DH, Lavery RF, Passannante MR, et al. Free fluid on abdominal computed tomography without solid organ injury after blunt abdominal injury does not mandate celiotomy. Am J Surg 2001; 182:6-9.[CrossRef][Medline]
  19. Herschorn S, Radomski SB, Shoskes DA, Mahoney J, Hirshberg E, Klotz L. Evaluation and treatment of blunt renal trauma. J Urol 1991; 146:274-276.[Medline]
  20. Pachter HL, Knudson MM, Esrig B, et al. Status of nonoperative management of blunt hepatic injuries in 1995: a multicenter experience with 404 patients. J Trauma 1996; 40:31-38.[Medline]
  21. Pachter HL, Guth AA, Hofstetter SR, Spencer FC. Changing patterns in the management of splenic trauma: the impact of non-operative management. Ann Surg 1998; 227:708-719.[CrossRef][Medline]
  22. Sartorelli KH, Frumiento C, Rogers FB, Osler TM. Non-operative management of hepatic, splenic and renal injuries in adults with multiple injuries. J Trauma 2000; 49:56-62.[Medline]
  23. Feliciano DV, Burch JM, Spiut-Patrianely V, Mattox KL, Jordan GL, Jr. Abdominal gunshot wounds: an urban trauma center’s experience with 300 consecutive patients. Ann Surg 1988; 208:362-370.[Medline]
  24. McConnell DB, Trunkey DD. Nonoperative management of abdominal trauma. Surg Clin North Am 1990; 70:677-688.[Medline]
  25. Nance FC, Wennar MH, Johnson LW, Ingram JC, Jr, Cohn I, Jr. Surgical judgment in the management of penetrating wounds of the abdomen: experience with 2,212 patients. Ann Surg 1974; 179:639-646.[Medline]
  26. Lowe RJ, Saletta JD, Read DR, Radhakrishnan J, Moss GS. Should laparotomy be mandatory or selective in gunshot wounds of the abdomen? J Trauma 1977; 17:903-907.[Medline]
  27. Renz BM, Feliciano DV. Unnecessary laparotomies for trauma: a prospective study of morbidity. J Trauma 1995; 38:350-356.[Medline]
  28. Kelemen JJ, Martin RR, Obney JA, Jenkins D, Kissinger DP. Evaluation of diagnostic peritoneal lavage in stable patients with gunshot wounds to the abdomen. Arch Surg 1997; 132:909-913.[Abstract]
  29. Zantut LF, Ivatury RR, Smith RS, et al. Diagnostic and therapeutic laparoscopy for penetrating abdominal trauma: a multicenter experience. J Trauma 1997; 42:825-831.[Medline]
  30. Fabian TC, Croce MA, Stewart RM, Pritchard FE, Minard G, Kudsk KA. A prospective analysis of diagnostic laparoscopy in trauma. Ann Surg 1993; 217:557-564.[Medline]
  31. Sosa JL, Arrillaga A, Puente I, Sleeman D, Ginzburg E, Martin L. Laparoscopy in 121 consecutive patients with abdominal gunshot wounds. J Trauma 1995; 39:501-506.[Medline]
  32. Udobi KF, Rodriguez A, Chiu W, Scalea TM. Role of ultrasonography in penetrating abdominal trauma: a prospective clinical study. J Trauma 2001; 50:475-479.[Medline]
  33. Boulanger BR, Kearney PA, Tsuei B, Ochoa JB. The routine use of sonography in penetrating torso injury is beneficial. J Trauma 2001; 51:320-325.[Medline]
  34. Rehm CG, Sherman R, Hinz TW. The role of CT scan in evaluation for laparotomy in patients with stab wounds of the abdomen. J Trauma 1989; 29:446-450.[Medline]
  35. Fletcher TB, Setiawan H, Harrell RS, Redman HC. Posterior abdominal stab wounds: role of CT evaluation. Radiology 1989; 173:621-625.[Abstract/Free Full Text]
  36. Easter DW, Shackford SR, Mattrey RF. A prospective, randomised comparison of computed tomography with conventional diagnostic methods in the evaluation of penetrating injuries to the back and flank. Arch Surg 1991; 126:1115-1119.[Abstract]
  37. McAllister E, Perez M, Albrinck M, Olsen S, Rosemurgy A. Is triple contrast computed tomographic scanning useful in the selective management of stab wounds to the back? J Trauma 1994; 37:401-403.[Medline]
  38. Phillips T, Sclafani SJ, Goldstein A, Scalea T, Panetta T, Shaftan G. Use of contrast enhanced CT enema in the management of penetrating trauma to the flank and back. J Trauma 1986; 26:593-601.[Medline]
  39. Hauser CJ, Huprich JE, Bosco P, Gibbons L, Mansour AY, Weiss AR. Triple-contrast computed tomography in the evaluation of penetrating posterior abdominal injuries. Arch Surg 1987; 122:1112-1115.[Abstract]
  40. Himmelman RG, Martin M, Gilkey S, Barrett JA. Triple-contrast CT scans in penetrating back and flank trauma. J Trauma 1991; 31:852-855.[Medline]
  41. Demetriades D, Velmahos G, Cornwell E, 3rd, et al. Selective nonoperative management of gunshot wounds of the anterior abdomen. Arch Surg 1997; 132:178-183.[Abstract]
  42. Velmahos GC, Demetriades D, Cornwell EE, 3rd, et al. Selective management of renal gunshot wounds. Br J Surg 1998; 85:1121-1124.[CrossRef][Medline]
  43. Renz BM, Feliciano DV. Gunshot wounds to the right thoracoabdomen: a prospective study of non-operative management. J Trauma 1994; 37:737-744.[Medline]
  44. Grossman MD, May AK, Schwab CW, et al. Determining anatomic injury with computed tomography in selected torso gunshot wounds. J Trauma 1998; 45:446-456.
  45. Ginzburg E, Carrillo EH, Kopelman T, et al. The role of computed tomography in selective management of gunshot wounds to the abdomen and flank. J Trauma 1998; 45:1005-1009.[Medline]
  46. Chiu WC, Shanmuganathan K, Mirvis SE, Scalea TM. Determining the need for laparotomy in penetrating torso trauma: a prospective study using triple-contrast enhanced abdominopelvic computed tomography. J Trauma 2001; 51:860-869.[Medline]



This article has been cited by other articles:


Home page
 TraumaHome page
C. Whitfield and J.P. Garner
The early management of gunshot wounds Part II: the abdomen, extremities and special situations
Trauma, January 1, 2007; 9(1): 47 - 71.
[Abstract] [PDF]

Home page
 Arch SurgHome page
A. Salim, B. Sangthong, M. Martin, C. Brown, D. Plurad, K. Inaba, P. Rhee, and D. Demetriades
Use of Computed Tomography in Anterior Abdominal Stab Wounds: Results of a Prospective Study
Arch Surg, August 1, 2006; 141(8): 745 - 752.
[Abstract] [Full Text] [PDF]

This Article
Right arrow Abstract Freely available
Right arrow Figures Only
Right arrow Full Text (PDF)
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Múnera, F.
Right arrow Articles by Velez, G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Múnera, F.
Right arrow Articles by Velez, G.

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
RADIOLOGY RADIOGRAPHICS RSNA JOURNALS ONLINE