Review of radiation risks from computed tomography: essentials for the pediatric surgeon

Background/Purpose

Over the past several years, increasing attention has been focused on the potential for radiation exposure from computed tomography (CT) for inducing the development of cancers. An understanding of these issues is important for the practice of pediatric surgery.

Methods

Medline based clinical review of current medical literature of the risks for the induction of cancers by CT. Data includes estimates of cancer risk from computer models, epidemiologic data from survivors of atomic bomb radiation exposure, and consensus opinions from expert panels.

Results

Review of scientific evidence demonstrates varied opinions, but consensus suggests there may be a potential for an increased risk of cancer from low level radiation exposure such as from CT. These calculations suggest that there may be as high as 1 fatal cancer for every 1000 CT scans performed in a young child.

Conclusions

Pediatric surgeons should be aware of the potential risks of CT. Minimizing the radiation risks of CT is a complex endeavor, and will require investments from pediatric surgeons as well as pediatric radiologists.     

Computed tomography before transfer to a level I pediatric trauma center risks duplication with associated increased radiation exposure

Introduction

Community hospitals commonly obtain computed tomographic (CT) imaging of pediatric trauma patients before triaging to a level I pediatric trauma center (PTC). This practice potentially increases radiation exposure when imaging must be duplicated after transfer.

Methods

A retrospective review of our level 1 PTC registry from January 1, 2004, to December 31, 2006, was conducted. Level I and II trauma patients were grouped based on whether they had undergone outside CT examination (head and/or abdomen) at a referring hospital (group 1) or received initial CT examination at our institution (group 2). Subgroups were analyzed based on whether duplicate CT examination was required at our PTC (Fischer's Exact test).

Results

A duplicate CT scan (within 4 hours of transfer) was required in 91% (30/33) of group 1 transfer patients, whereas no group 2 patient required a duplicate scan (0/55; P < .0001). There was no significant difference within the groups for weight, age, or intensive care unit length of stay.

Conclusion

A significant number of pediatric trauma patients who receive CT scans at referring hospitals before transfer to our level I PTC require duplicate scans of the same anatomical field(s) after transfer, exposing them to increase potential clinical risk and cost.     

Repeat abdominal computed tomography scans after pediatric blunt abdominal trauma: missed injuries, extra costs, and unnecessary radiation exposure

Purpose

We hypothesized that pediatric blunt trauma patients, initially evaluated at nontrauma centers with abdominal computed tomography (CT) scans, often undergo repeat scans after transfer. This study was designed to quantify this phenomenon, assess consequences, and elucidate possible causes.

Methods

This article is an institutional review board-approved, retrospective chart review of pediatric blunt abdominal trauma patients transferred to a level I trauma center from 2002 to 2007 and evaluated with abdominal CT at the trauma center or at a referring facility.

Results

A total of 388 patients met the study criteria, with 6 patients being excluded because of inability to verify outside records resulting in study group of 382 patients. Of those 382 patients, 199 (52%) underwent abdominal CT before transfer. Thirty-six (18%) of those 199 patients underwent repeat CT scanning at our level I trauma center. Of these 36 patients, 19 (53%) were transferred without their outside CT scans, with 10 (53%) of these 19 having significant abdominal injuries. Of the remaining 17, 6 (17%) had repeat scans to assess changes in vital signs, or patient condition, or because of inadequate outside imaging. The remaining 11 (30%) were repeated despite an acceptable outside CT and no change in patient condition. Only 2 of 11 resulted in changed management. Additional radiation delivered from these repeat scans totaled 180 mSv, and additional patient charges totaled more than $110,000. There was an apparent trend toward increased repeat scanning (from 6.7% in 2002 to 16.7% in 2007).

Conclusions

Abdominal CT scans, for evaluation of pediatric blunt trauma, are frequently repeated after transfer from outside hospitals. In many cases, repeat scans provide useful diagnostic information. However, more than 80% of repeat scanning is potentially preventable with better education of transport personnel (paramedics, emergency medical technicians, and nurses) and emergency department physicians.     

An analysis of proctoscopy vs computed tomography scanning in the diagnosis of rectal injuries in children: which is better?

Background

Current dogma suggests that the diagnosis of rectal injury can be made after physical examination and proctoscopy (PR). However, anecdotal evidence suggests that these modalities lack specificity when applied to children and that computed tomography (CT) scanning may be superior. A direct comparison between CT scanning and PR has not been performed. We therefore sought to compare CT with PR in the diagnosis of rectal injury by analyzing our large institutional experience.

Methods

To assess institutional outcome, the charts of all children younger than 18 years admitted to our level I trauma center (1999-2004) were prospectively collected and retrospectively assessed. Demographics, diagnostic accuracy (PR vs CT), and outcome (length of stay, days in the intensive care unit [ICU], Injury Severity Score, and missed injury) were assessed.

Results

There were 24 injuries (63% boys, 71% blunt, 100% survival), and diagnostic modality included the following: PR, 37.5%; CT, 37.5%; laparotomy alone, 8%. Length of stay (PR 5.7 ± 6.2 vs CT 13.7 ± 22.2, NS) were similar between groups. Of the missed rectal injuries, 66% of patients undergoing PR had missed injuries that were ultimately detected by CT whereas 33% of the patients undergoing CT scan had a missed injury.

Conclusion

CT is at least as accurate as PR in diagnosing pediatric rectal injury. Consideration of early scanning as opposed to PR may improve diagnosis and outcome in these patients.     

Diagnosing acute appendicitis: are we overusing radiologic investigations?

Purpose

Acute appendicitis is the most common emergency presenting to pediatric surgeons. With proper history and thorough physical examination, the diagnosis of the condition clinically should approach 90%. With the increasing ease of performing radiologic investigations because of technological advances, more ultrasound and computed tomography (CT) are used to help diagnosing appendicitis. The aim of this study is to review the trend of diagnosing appendicitis in a single center and discuss the implications.

Methods

A retrospective analysis was carried out for all patients who were admitted with acute appendicitis between 1997 and 2007. The methods of diagnosis were divided into 3 groups as follows: clinical, ultrasound, and CT. The demographics and operative findings were noted. Statistical analysis was done using Fisher's Exact test and paired t test when appropriate. A value of P < .05 was considered to be statistically significant.

Results

During this period, a total of 254 patients (167 boys and 87 girls) were admitted with appendicitis. The average age at presentation was 12 years, and the mean duration of symptoms before presentation was 2 days. For 11 years, there was an initial rise of the use of ultrasound (10% in 1997 to a peak of 60% in 2005). This percentage decreased with a corresponding rise of the use of CT scan (0% in 1997 to 35% in 2007). There was no correlation found between the use of adjunct investigations and the severity of appendicitis found at operation, suggesting an overreliance of CT.

Conclusion

It appears that there is an increasing trend in using radiologic investigations for the diagnosis of appendicitis for the past 11 years. With the association of cancer in later life and early radiation exposure well documented, it would be advisable to avoid the use of CT if possible.     

CT scan and the pediatric trauma patient--are we overdoing it?

Background

Recent literature expresses concern for an increased risk of cancer in children exposed to low-dose radiation during computed tomography (CT). In response, children’s hospitals have implemented the ALARA (as low as reasonably achievable) concept, but this is not true at most adult referring institutions. The purpose of this study was to assess the diagnostic necessity of CT in the evaluation of pediatric trauma patients.

Methods

A retrospective review was conducted of the trauma database at a large, level I, freestanding children’s hospital with specific attention to the pattern of CT evaluations.

Results

From January 1999 to October 2003, 1,653 children with traumatic injuries were evaluated by the trauma team, with 1,422 patients undergoing 2,361 CT scans. Overall, 54% of obtained scans were interpreted as normal. Fifty percent of treated patients were transferred from referring hospitals. Approximately half arrived with previous CT scans with 9% of these requiring further imaging. Of the 897 patients that underwent abdominal CT imaging, only 2% were taken to the operating room for an exploratory laparotomy. In addition, of those patients who had abnormal findings on an abdominal CT scan, only 5% underwent surgical exploration.

Conclusions

CT scans are used with regularity in the initial evaluation of the pediatric trauma patient, and perhaps abdominal CT imaging is being used too frequently. A substantial number of these scans come from referral institutions that may not comply with ALARA. The purported risk of CT radiation questions whether a more selective approach to CT evaluation of the trauma patient should be considered.     

Severity of head computed tomography scan findings fail to explain racial differences in mortality following child abuse

Introduction

Differences in head injury severity may not be fully appreciated in child abuse victims. The purpose of this study was to determine if differential findings on initial head computed tomography (CT) scan could explain observed differential outcome by race.

Methods

We identified 164 abuse patients from our trauma registry with an Injury Severity Score (ISS) ≥ 15. Their initial head CT scan was graded from 1 to 4 (normal to severe). Statistical analysis was performed to asses the correlation between race, head CT grade, Glascow Coma Scale (GCS) score, and mortality.

Results

Overall mortality was 17%: 11% for white children, 32% for African-American children (P < .05). In review of the head CT scans there was no difference by race in types of injuries or head CT grade. Using a multivariate regression model, African-American race remained an independent risk factor for mortality with an odd ratio of 4.3 (95% confidence interval [CI] 1.6-11.5).

Conclusion

African-American children had a significantly higher mortality rate despite similar findings on initial head CT scans. Factors other than injury severity may explain these disparate outcomes.     

The correlation of the D-dimer test and biphasic computed tomography with mesenteric computed tomography angiography in the diagnosis of acute mesenteric ischemia

Background

Early diagnosis is the main factor to improve the outcome of acute mesenteric ischemia (AMI). The goal of this study was to assess the correlation of the D-dimer test and biphasic computed tomography (CT) with mesenteric CT angiography for the diagnosis of AMI.

Methods

Selected consecutive patients with a clinical suspicion of AMI were admitted to the study. Blood samples were taken before biphasic CT with mesenteric CT angiography examination.

Results

The sensitivity and specificity values of biphasic CT with mesenteric CT angiography were 92.9% and 89.5%, respectively. The sensitivity and specificity of D-dimer testing for the diagnosis of AMI were 94.7% and 78.6%, respectively. D-dimer levels higher than 3.17 μg fibrinogen equivalent units/mL were more specific (P < .0001) and acted similarly to the biphasic CT with mesenteric CT angiography in the diagnosis of AMI.

Conclusions

In the setting of early diagnosis of AMI, the D-dimer test may improve our ability to diagnose patients in whom we cannot use multidetector row CT with CT angiography.     

CT scans may not reduce the negative appendectomy rate in children

Background/purpose

Concern about an increased lifetime risk of cancer in children who have undergone a single computed tomography (CT) scan prompted us to review utilization of this diagnostic test in our appendicitis population.

Methods

From 1998 to 2001, the records of 720 children admitted to our hospital with a diagnosis of appendicitis were reviewed for adjunct diagnostic modalities, including ultrasonography (USG) and CT scanning. Negative appendectomy rates were determined by the final pathologic report. Statistical comparisons were made using the χ² test, and significance was assigned at P < .05.

Results

The use of ultrasound scan for diagnosing appendicitis decreased from 20.0% in 1998 to 7.0% in 2001 (P < .01). Conversely, the use of CT scans increased from 17.6% in 1998 to 51.3% in 2001 (P < .001). During this time period the difference in the negative appendectomy rate was not statistically significant (P < 0.20). Of the negative appendectomies, 11 of these patients had a USG interpreted as positive for appendicitis (22.0%), and 9 had a CT scan interpreted as positive (18.0%).

Conclusions

Liberal use of CT scans in diagnosing appendicitis in children has not resulted in a decreased negative appendectomy rate. Potentially harmful radiation exposure should prompt pediatric surgeons to reevaluate the role of CT scanning in the management of children with suspected appendicitis.     

The influence of advanced radiographic imaging on the treatment of pediatric appendicitis

Purpose

Since 1998, the use of advanced radiographic imaging with computed tomography (CT) and/or diagnostic ultrasound (US) has increased dramatically for the diagnosis of acute appendicitis in children. This study investigates the impact of this imaging on the evaluation, management, and outcome of pediatric patients who underwent appendectomy for suspected appendicitis.

Methods

Retrospective review of 197 consecutive children with a preoperative diagnosis of acute appendicitis, from January 2002 through May 2004, undergoing appendectomy at a university-affiliated community hospital by pediatric and general surgeons.

Results

Patients were divided into two groups: imaged (n = 106; 54%) and nonimaged (n = 91; 46%). Groups were similar with respect to age, sex, temperature, white blood count, and insurance status. Ninety-seven imaged patients had CT, 6 had US, and 3 had both CT and US. Seventy-one percent of imaging studies were ordered by emergency department physicians and 24% by treating surgeons. Average wait from emergency department triage to operative incision for the imaged and nonimaged groups was 12.1 and 5.4 hours, respectively (P < .0001). Both groups had similar perforation rates (imaged: 15.1%, nonimaged: 14.6%). Negative appendectomy rates were 10.4% (imaged) and 4.4% (nonimaged). Average hospital charges were $11,791 (imaged) and $9360 (nonimaged) (P = .001). Time on antibiotics, complication rates, and length of stay were similar for both groups.

Conclusions

More than half of pediatric patients with suspected appendicitis now undergo advanced imaging and experience a significant delay in surgical treatment with a 26% increase in hospital charges and no clear-cut improvement in diagnostic accuracy nor outcome, when compared with evaluation by the treating surgeons.     

The significance of contrast blush on computed tomography in children with splenic injuries

Purpose

Most children and adults with blunt splenic injuries are treated nonoperatively by well-established management protocols. The “blush sign” is an active pooling of contrast material within or around the spleen seen during intravenous enhanced computed tomography (CT) scan. Adult treatment algorithms often include the “blush sign” as an indication for embolization or surgical intervention. This study was designed to evaluate the implications of the “blush sign” in children with blunt splenic injuries.

Methods

A review was performed of all children with blunt splenic injuries treated between January 1996 and December 2001 at a level I pediatric trauma center using an established solid organ injury protocol. The demographic, CT imaging, and outcome data were recorded. Treatment was categorized as operative or nonoperative. A single pediatric radiologist retrospectively reviewed all available CT scans to confirm injury grade and the presence or absence of a “blush sign.”

Results

There were 133 eligible children admitted with blunt splenic trauma, with a mean age of 9.1 years (range, 1 to 15), including 86 children with an abdominal CT available for review. A “blush sign” on initial CT scan was noted in 6 children, all with grade 3 or above splenic injuries, 5 of who were treated nonoperatively. In this series, the single child with a “blush sign” who did not respond to nonoperative treatment had a severe polytrauma requiring urgent splenectomy and left nephrectomy. None of the children died of their splenic injury.

Conclusions

Although associated with higher grades of injury, the blush sign did not mandate embolization or surgical intervention in children with blunt splenic trauma in this series. Severe splenic injuries with a blush sign on the initial CT scan may be successfully treated nonoperatively when using an established treatment protocol. Management should be based primarily on physiological response to injury rather than the radiologic features of the injury.     

Is sonography reliable for the diagnosis of pediatric blunt abdominal trauma?

Background

Computerized tomography (CT) is considered as the imaging study of choice for blunt abdominal trauma in children. Nevertheless, recent investigations clearly indicate an increased risk of cancer in children exposed to radiation during abdominal spiral CT. Therefore, alternative strategies should be used for the diagnosis and surgical decision making in blunt abdominal trauma in children.

Methods

Retrospective analysis included all children with intraabdominal organ rupture after blunt abdominal trauma. Patients were diagnosed by a standardized emergency protocol that included primary clinical assessment and repeated ultrasound but not routine CT. Efficacy of abdominal ultrasound was evaluated in regard to safe diagnosis and appropriate surgical decision making.

Results

The study included 35 children with intraabdominal organ rupture diagnosed by ultrasound. One fifth (7/35) of the patients were polytraumatized, whereas 28 of 35 had an isolated blunt abdominal trauma. All patients underwent immediate ultrasound scanning of the abdomen and retroperitoneal space. Two patients were immediately operated because of hemodynamically instability. Four of 7 polytraumatized patients and 7 of 28 patients with isolated blunt abdominal trauma were additionally diagnosed by spiral CT. Only 1 patient underwent subsequent surgery because of the findings in the CT. Ultrasound was effective in more than 97% (34/35) of the patients for diagnosis and appropriate surgical decision making.

Conclusion

Ultrasound combined with clinical assessment presents an effective method for safe diagnosis and appropriate surgical decision making in pediatric blunt abdominal trauma. Selected cases with polytrauma and/or unequivocal findings in the ultrasound should undergo abdominal CT. Patients requiring abdominal CT should have an anticipated benefit that exceeds the radiation risk. The importance of repeated clinical assessment cannot be overstated.     

From gunstore to smoking gun: tracking guns that kill children in North Carolina

Purpose

This study reviews the epidemiology of pediatric firearm deaths in North Carolina and estimates the time from the retail sale of guns to their involvement in pediatric firearm deaths.

Methods

The authors reviewed autopsy reports for all children 0 to 14 years of age that died of firearm-related injuries in North Carolina from January 1999 through December 2002. Data obtained included demographic information, firearm type, and manner of death. Data from the Bureau of Alcohol, Tobacco and Firearms, which traced guns involved in crimes and determined the time elapsed from purchase to their involvement in a crime (ie, time-to-crime were also reviewed).

Results

During the study period, 40 children died of firearm injuries. Mean age was 7.6 years. Handguns were responsible for the majority of deaths (59%) followed by shotguns (27%), rifles (10%), and undetermined cause (10%). Most deaths were homicides (67%) followed by unintentional death (18%), suicide (13%), and undetermined cause (2%). Most crime guns (76%) were purchased legally, and many (40%) had a time-to-crime of less than 3 years.

Conclusions

Legally purchased firearms pose a significant threat to children in North Carolina. A more restrictive approach to the sale of handguns is a logical approach to reducing pediatric firearm-related deaths in the United States.     

An evidence-based clinical protocol for diagnosis of acute appendicitis decreased the use of computed tomography in children

Purpose

The increased use of computed tomography (CT) to diagnose appendicitis in children has led to a concern for the possibility of increased CT-related cancer morbidity. We designed a clinical protocol for the diagnosis and treatment of appendicitis in children in an attempt to decrease the use of CT scans at our institution.

Methods

Patients who had surgical consultation for suspected appendicitis were placed on the clinical protocol. Data concerning diagnosis and treatment were collected prospectively. Retrospective data from patients admitted to our institution with acute appendicitis before the clinical protocol were collected as historical controls.

Results

One hundred twelve patients were diagnosed and treated by our protocol between June and November 2009. Of these, 100 patients underwent an appendectomy for acute appendicitis. They were compared with 146 patients from 2007. In-house CT use decreased from 71.2% to 51.7% (P = .01). Preoperative ultrasound use increased from 2.7% to 21% (P < .001). The negative appendectomy rate increased (6.8% vs 11%, P = .25).

Conclusions

Our findings suggest that the implementation of an evidence-based clinical protocol for the diagnosis and treatment of acute appendicitis in children may safely decrease the use of CT scans and increase the use of ultrasound.     

If a picture is worth a thousand words, what is a trauma computerized tomography panel worth?

Background

There has been a progressive increase in the use of computerized tomography (CT) scans for evaluating trauma patients. The purpose of this study was to quantify that trend and consider the implications it holds for resource use.

Methods

Data were combined from the trauma registry and the radiology department’s administrative information system at a level I trauma center to define the radiographic use patterns applied to all trauma activations during a 3-month sampling period in each of 4 years.

Results

Trauma activations increased by 21% whereas total radiographic studies increased by 82%. The proportion of CT scans to total studies increased progressively from 18% to 27%. The average number of CT studies per patient increased from 2.68 ± 3.09 to 6.88 ± 7.50. CT use increased for patients presenting by primary or secondary transport, regardless of triage classification. In the final sampling period, CT scans alone generated an average of 3,726 images per day to be reviewed.

Conclusions

Increasing use of multi-image studies is facilitated by improvements in technology and medical-legal pressures. However, extensive imaging can stress overburdened trauma systems. Additional studies are needed to assess the implications of increasing radiographic use on trauma outcomes.     

Occult pneumothorax in Chinese patients with significant blunt chest trauma: Incidence and management

Background

Occult pneumothorax (OP) is a pneumothorax not visualised on a supine chest X-ray (CXR) but detected on computed tomography (CT) scanning. With increasing CT use for trauma, more OP may be detected. Management of OP remains controversial, especially for patients undergoing mechanical ventilation. This study aimed to identify the incidence of OP using thoracic CT as the gold standard and describe its management amongst Hong Kong Chinese trauma patients.

Methods

Analysis of prospectively collected trauma registry data. Consecutive significantly injured trauma patients admitted through the emergency department (ED) suffering from blunt chest trauma who underwent thoracic computed tomography (TCT) between in calendar years 2007 and 2008 were included. An OP was defined as the identification (by a specialist radiologist) of a pneumothorax on TCT that had not been previously detected on supine CXR.

Results

119 significantly injured patients were included. 56 patients had a pneumothorax on CXR and a further 36 patients had at least one OP [OP incidence 30% (36/119)]. Bilateral OP was present in 8/36 patients, so total OP numbers were 44. Tube thoracostomy was performed for 8/44 OP, all were mechanically ventilated in the ED. The remaining 36 OP were managed expectantly. No patients in the expectant group had pneumothorax progression, even though 8 patients required subsequent ventilation in the operating room for extrathoracic surgery.

Conclusion

The incidence of OP (seen on TCT) in Chinese patients in Hong Kong after blunt chest trauma is higher than that typically reported in Caucasians. Most OP were managed expectantly without significant complications; no pneumothorax progressed even though some patients were mechanically ventilated.     

Accuracy of computed tomography in predicting appendiceal perforation

Background

Some surgeons use nonoperative management with or without interval appendectomy for patients who present with perforated appendicitis. These strategies depend on accurately delineating perforation by computed tomography (CT). Since 2005, our institution has used an evidence-based definition for perforation as a hole in the appendix or fecalith in the abdomen. This has been shown to clearly separate those with a high risk of abscess from those without. To quantify the ability of CT to identify which patients would meet these criteria for perforation, we tested 6 surgeons and 2 radiologists who evaluated blinded CT scans.

Methods

A junior and senior surgical residents, 2 staff interventional radiologists, and 4 attending pediatric surgeons with 3 to 30 years of experience reviewed 200 CT scans of pediatric patients who had undergone a laparoscopic appendectomy. All CT scans were reviewed electronically, and the reviewers were blinded to the results, outcome, and intraoperative findings. None of the patients had a well-formed abscess on CT. The reviewers were asked to decide only on perforated or nonperforated appendicitis according to our intraoperative definition. Clinical admission data were reviewed and compared between groups.

Results

In total, the reviewers were correct 72% of the time with an overall sensitivity of 62% and a specificity of 81%. The overall positive predictive value was 67%, and the negative predictive value was 77%.

Conclusions

This study shows that in the absence of a well-formed abscess, the triage of patient care based on a preoperative diagnosis of perforation from CT may be imprudent and subject a portion of the population to an unnecessarily prolonged course of care.     

Three-dimensional visualization and virtual simulation of resections in pediatric solid tumors

Purpose

Three-dimensional visualization of solid tumors is possible because of high-resolution computed tomography and magnetic resonance imaging scans. However, additional preoperative information is often desirable in complex malignancies. For the first time, the authors present a model of preoperative 3-dimensional visualization and virtual resections in pediatric solid tumors.

Methods

Image analysis of various pediatric tumors was performed using the research software HepaVision2 (MeVis, Bremen). Organs, tumors, and the vascular system were extracted from multislice computed tomography scans. After hierarchical analysis of the vascular system, territories supplied or drained by the major vascular branches were calculated. Results were explored and virtual resections of organs were carried out using the research software InterventionPlanner (MeVis, Bremen). Data were correlated to intraoperative findings.

Results

Four hepatic malignancies, 4 renal tumors, and 3 other neoplasms were analyzed. The technique of 3-dimensional visualization was feasible for all investigated children (mean age 5 years and 9 months). Spatial relations between physiological and pathological structures were identified, and anatomical structures (vessels, tumor tissue, and organ parenchyma) were determined using colorimetric encoding. Virtual simulations of tumor resection were used successfully for planning of surgical procedures in the hepatic and renal tumors.

Conclusions

The technique of 3-dimensional tumor visualization and virtual simulation of tumor resections provides the basis for a successful planning of complex tumor resections in children. The efficiency of these techniques should be further analyzed in series with higher numbers and differentiations of tumors.     

Donor/recipient algorithm for management of the middle hepatic vein in right graft live donor liver transplantation

Background

The aim of this study was to delineate an algorithm for donor and recipient criteria and middle hepatic vein (MHV) management in right-graft live-donor liver transplantation (LDLT) on the basis of computerized 3-dimensional computed tomographic image analysis.

Methods

Data on 94 consecutive right-graft LDLTs were prospectively collected. Graft and remnant data for the first 23 cases were retrospectively evaluated by means of 3-dimensional computed tomographic reconstructions, and on the basis of that preliminary series, a graft selection algorithm using 3 parameters—hepatic vein dominance classification, graft and remnant graft volume/body weight ratios, and congestion volumes—was created. It was subsequently applied to the next 71 right-graft LDLTs.

Results

Fifty-nine right grafts contained the MHV. Four of the 12 grafts with no MHVs required MHV reconstructions. In 18 cases, small liver grafts were used. The postoperative function of liver grafts and remnants with versus without MHVs was not statistically different.

Conclusions

The proposed algorithm favored the inclusion of the MHV with the right grafts. It also allowed for the procurement of grafts that were potentially small for size without compromising donor or recipient safety.     

The value of surgery in directing therapy for patients with Wilms' tumor with pulmonary disease. A report from the National Wilms' Tumor Study Group (National Wilms' Tumor Study 5)

Background/Purpose

Computed tomography (CT) of the chest with its increased sensitivity frequently identifies lesions not visible on chest radiograph. Treatment of such lesions is controversial. A recent review suggests that patients with Wilms' tumor with pulmonary lesions detected only by CT, who were treated with dactinomycin and vincristine, have an inferior outcome compared with those who also received pulmonary radiation therapy (RT) and doxorubicin. It is important to determine if these small lesions seen only on CT represent metastatic disease and whether patients with these lesions require RT and/or doxorubicin for optimal outcome.

Methods

Patients with Wilms' tumor with lung metastasis, registered on National Wilms' Tumor Study 5, were reviewed, and those with CT-only lesions who had a radiology and surgical checklist submitted were identified. The treatment regimens of these patients and the histological findings of the pulmonary lesions are presented. We analyzed the pathological findings by whether the patients had single or multiple lesions.

Results

Of 2498 patients registered on National Wilms' Tumor Study 5, 252 had pulmonary metastases. Of these patients, 129 (5.2%) had CT-only lesions (<1 cm). Forty-two of these patients (20 boys and 22 girls) underwent lung biopsy at the discretion of the attending physicians. The local tumor stages in these patients were stage I (7%), II (34%), and III (59%). The treatment stages in these patients were stage I (n = 3, 2 drugs), II (n = 3, 2 drugs), III (n = 12, 3 drugs); and IV (n = 24, 3 drugs + RT). There were 16 patients with isolated lung lesions and 26 with multiple lesions, average size 5.8 ± 0.5 mm. Of 16 isolated lesions, 13 patients (82%) and 69% (18/26) with multiple lesions had tumor on biopsy. Of the 24 who received RT, 8 had a negative biopsy and, thus, may not have needed the RT. Five of 6 treated with just 2 drugs may have been undertreated. Nine of 12 treated with 3 drugs had tumor on biopsy.

Conclusions

Computed tomography-only pulmonary lesions are not invariably tumor, demonstrating the need for histopathological confirmation. Biopsy remains critical until radiographic techniques allow differentiation between benign and malignant lesions to optimally direct therapy.