Peliosis hepatis in a dog infected with Bartonella henselae

A 6-year-old spayed female Golden Retriever was examined because of generalized weakness and abdominal distention. Abdominal ultrasonography revealed a large quantity of peritoneal fluid. In addition, the liver appeared larger than normal and contained multiple, small, nodular masses and cyst-like structures. Abdominal exploratory surgery was performed, and 5 L of serosanguineous peritoneal fluid was removed. Gross lesions were not found in the stomach, kidneys, intestines, adrenal glands, or urinary bladder. There were diffuse cystic nodules in all liver lobes. The dog did not recover from anesthesia. A diagnosis of peliosis hepatis was made on the basis of gross and histologic appearance of the liver. A polymerase chain reaction assay revealed Bartonella henselae DNA in liver specimens. To our knowledge, this is the first report of molecular evidence of B henselae infection in a dog with peliosis hepatis.

Right anterior subphrenic space: an important site for the early detection of intraperitoneal fluid on abdominal CT

BACKGROUND

Small rinds of free fluid are frequently seen in the right anterior subphrenic space. Therefore, we investigated patients undergoing abdominal computed tomography (CT) to see whether early fluid collections are seen preferentially at this or any other site.

METHODS

CT examinations of 59 randomly selected patients with minor or moderate quantities of free intraperitoneal fluid were analyzed. The location of the fluid was determined [subphrenic spaces, the right hepatorenal fossa (Morison's pouch), paracolic gutters, pelvis (pouch of Douglas)]. The amount of fluid in each location was subjectively quantified (none, trace, small, or moderate).

RESULTS

Free fluid was seen most frequently in the right anterior subphrenic space (44/59 patients, 75%) and pelvis (43/59 patients, 73%). Eight patients had intraperitoneal fluid at an isolated location (three in the pelvis alone, two in the left subphrenic space, one in the right subphrenic space, and one in each of the right and left paracolic spaces).

CONCLUSIONS

Contrary to popular belief, intraperitoneal fluid is not always seen first in the pelvis when the patient is in the supine position. Although fluid is not consistently seen first in any specific location, the subphrenic space (especially the right anterior) is a common site where small quantities of fluid may be identified.

Competency-based instruction to improve the surgical resident technique and accuracy of the trauma ultrasound

In a surgical trauma center, programs and workshops have improved the performance on focused abdominal sonogram for trauma (FAST). The purpose of this single-blind study was to prove that a cadaver laboratory competency-based instruction program may be an effective method of FAST training to acquire the skills that would be applied in the trauma room. The study was divided in two parts, laboratory and clinical. Nine surgical residents were divided into two groups: Group I performed the test only once, and Group II performed the training twice. A third "group" was the senior ultrasound technician, whose readings served as our "gold standard" with which to compare the resident readings (Group III). Using cadavers, a 2-cm catheter was introduced into the peritoneal cavity. Sequential aliquots of normal saline were introduced into the abdominal cavity at 0-, 200-, 400-, 600-, and 1000-cc increments in each group tested. The residents were asked to describe their examinations for the presence or absence of fluid in the abdomen. The ultrasound examination was then performed with the cadaver in three different positions to study if there was any difference of fluid detection in varied positions. True positive, true negative, and accuracy were then calculated comparing the three different groups of test sonographers. In the second part of the study, the same residents were then followed in the trauma room, where they performed the FAST in the absence of the ultrasound technician during emergencies. As in the laboratory, the accuracy of their reading compared with that of the ultrasound technician was also evaluated. From 400 cc and upward, Group II began having an overall significantly superior accuracy than the first group and the technician in most quadrants examined. The trend was apparent for more accurate results in all quadrants and positions by all groups as the fluid was increased. Overall, group II was most superior in detection of intra-abdominal fluid in the cadaver. In the clinical scenario, the residents as a whole had similar accuracy (92% vs 96%) in reading FAST as the ultrasound technician. Our results suggest that surgical residents have the ability to detect fluid in the abdomen, there exists a fast learning curve, and the minimum detection level of fluid was between 200 and 400 cc in the peritoneal cavity in the laboratory. Surgical residents were able to detect intra-abdominal fluid in the trauma situation, as shown by the 92 per cent accuracy of the FAST in the emergency situation. We conclude that a cadaver laboratory training program is an important adjunct to improve the skills of the resident in performing and reading FAST.

Ultrasound features of intussusception predicting outcome of air enema

OBJECTIVE

To examine features identified on US which predict success or failure of air-enema reduction of intussusception.

MATERIALS AND METHODS

A retrospective study of 117 consecutive episodes of intussusception, presenting for US over a 6-year period. The specific features examined were: free fluid within the peritoneum, small-bowel obstruction, colonic wall thickness, and fluid trapped between the colon and the intussusceptum.

RESULTS

The overall reduction rate, irrespective of US features, over the 6-year period was 72 %. Reduction rates were significantly higher with the absence of free fluid, trapped fluid, or small-bowel obstruction (93 %). The presence of trapped fluid predicted an unfavourable outcome, with a significantly lower success rate (25 %). Colonic wall thickness did not predict outcome; in successful reductions, mean wall thickness was 7.2 mm and in failed reductions 7.6 mm.

CONCLUSIONS

Where free fluid, small-bowel obstruction, and trapped fluid are absent, almost 100 % success with air-enema reduction should be achievable. Where trapped fluid is present, air enema should be performed cautiously to avoid perforation caused by overvigorous attempts at pneumatic reduction of an incarcerated intussusception.

Pelvic abnormalities in hysterectomized patients-role of early postoperative ultrasonographic evaluation

OBJECTIVE

To assess the incidence of post-hysterectomy pelvic fluid collection in the early postoperative period and to study its natural history.

STUDY DESIGN

Cross-sectional, prospective, observational study.

PATIENTS AND METHODS

The study sample comprised 36 consecutive patients undergoing hysterectomy for benign conditions in our department. All patients underwent two pelvic ultrasonographic examinations, the first on the third postoperative day and the second one year later. All postoperative complications were thoroughly evaluated.

RESULTS

Thirty-two patients completed the study evaluations. Abnormal ultrasonographic findings were detected in 4 of them on the early postoperative scan. Three (9.4% of the sample) had pelvic fluid collections which persisted on the follow-up scan. The fourth patient had a simple ovarian cyst 4 cm in diameter which disappeared on follow-up. None of the patients with pelvic fluid collections had a febrile morbidity during the postoperative course.

CONCLUSIONS

Transvaginal ultrasonography can detect asymptomatic early postoperative pelvic fluid collections and enables conservative management, thereby reducing patients stress, medical costs, and the need for unnecessary interventions.

The past, the present and future of the OK-432 therapy for patients with malignant effusions

For the past 20 years, our group has treated over 400 cases of malignant effusion by the intraperitoneal injection of streptococcal preparation OK432 (OK-432 therapy) and has investigated extensively the antitumor mechanisms of this therapy. Prospective clinical data has demonstrated that the OK-432 therapy induced a definite reduction of the effusions in around 60% (responders) of cases and significantly prolonged the survival time in patients who responded well. In addition, a definite reduction of original tumor mass volume was found in around 20% of cases. We have shown that OK432-induced neutrophils, lymphocytes, and probably macrophages may play an important role in tumor cell destruction in ascites. Tumor necrosis factor alpha (TNF-alpha)-induced CD11b/CD18 expression on leukocytes and interferon-gamma (IFN-gamma)-induced ICAM-1 expression on tumor cells may play an important role in leukocyte-mediated tumor destruction. It has also been shown that OK-432 induces various cytokines, such as TNF-alpha, TNF-beta, IFN-alpha IFN-gamma, interleukin-1 (IL-1), IL-2, IL-6, IL-12, tumor growth inhibitory factor(s) (TGIF), and possibly unknown apoptosis-inducing factor(s). Some of these cytokines have been adduced as representing the antitumor activity. These data suggest that two pathways of antitumor activity, i.e., cell-mediated and cytokine-mediated, can be induced simultaneously in the peritoneal cavity. OK-432 therapy may be valuable in the management of patients with malignant effusions. Future clinical and basic research should contribute to further progress in OK-432 therapy.

Diagnostic accuracy of transvaginal ultrasound in detecting free pelvic fluid

OBJECTIVE

To evaluate the diagnostic accuracy of transvaginal ultrasonography in detecting and measuring free pelvic fluid.

STUDY DESIGN

Eighty-two patients undergoing diagnostic or therapeutic laparoscopy at a tertiary care center were prospectively assessed before surgery by transvaginal ultrasound. Free pelvic fluid was measured in two ultrasonographic planes. These measurements were compared to the volume of fluid aspirated during laparoscopy.

RESULTS

The mean volumes reported for transvaginal ultrasound were significantly lower than those observed at laparoscopy (mean milliliters +/- SEM, 2.54 +/- 0.5 versus 9.42 +/- 1.3, P < .001). The smallest volume of free pelvic fluid that was consistently detected by ultrasound was 8 mL. Whenever no fluid or < 1 mL was detected by transvaginal ultrasound, a small volume of fluid was found at laparoscopy (mean milliliters +/- SEM, 1.6 +/- 0.47). The sensitivity of transvaginal ultrasound was 83% and specificity was 69%.

CONCLUSION

Transvaginal ultrasound is a sensitive method of detecting the presence of > 8 mL of free pelvic fluid and therefore is an important diagnostic tool in the assessment of pelvic pathology associated with increased peritoneal fluid.

Echogenic peritoneal fluid as an isolated sonographic finding: significance in patients at risk of ectopic pregnancy

Echogenic intraperitoneal fluid in any quantity noted on sonography is thought to indicate a very high likelihood of ectopic pregnancy (EP) in patients at risk. We retrospectively reviewed 12 consecutive symptomatic patients with a positive pregnancy test in whom sonography revealed echogenic fluid as an isolated finding without evidence of intrauterine pregnancy and in whom follow-up was available. Final diagnoses were EP in seven patients (58%) and spontaneous abortion in five (42%). EP was diagnosed in all four patients with a large amount of echogenic fluid, but in only three (38%) of eight patients with a small-to-moderate amount of echogenic fluid. We conclude that a small-to-moderate amount of echogenic fluid noted as an isolated finding may not be highly predictive of EP.

Hepatic abscesses in 13 dogs: a review of the ultrasonographic findings, clinical data and therapeutic options

Historical, physical examination, clinicopathologic, radiographic and ultrasonographic findings of 13 dogs with hepatic abscesses were reviewed. Liver abscessation was characterized by number, size, shape, echogenicity and location. Solitary lesions greater than 3 cm were more common than multiple ones. The abscesses were mainly poorly echogenic lesions, often with central cavitation. The shape of the lesion ranged from round to oval or irregular. Enhancement artifact, abdominal effusion, regional lymphadenopathy and hyperechoic perihepatic fat, were identified in several dogs. Ultrasound-guided aspiration was performed in 10 of 13 dogs, and confirmed abscessation with cytologic and microbiologic evaluation. Ultrasound-guided percutaneous drainage of abscesses was performed as an adjunct to medical management in four dogs.

Benign and malignant ovarian masses: selection of the most discriminating gray-scale and Doppler sonographic features

PURPOSE

To determine the gray-scale and Doppler sonographic features that best enable discrimination between malignant and benign ovarian masses and develop a scoring system for accurate diagnosis with these features.

MATERIALS AND METHODS

Gray-scale and Doppler sonographic features of 211 adnexal masses were correlated with the final diagnosis; the most discriminating features for malignancy were selected with stepwise logistic regression.

RESULTS

Twenty-eight masses were malignant and 183 benign. All masses with a markedly hyperechoic solid component or no solid component were benign. For masses with a nonhyperechoic solid component, additional features that allowed statistically significant discrimination of benignity from malignancy were, in decreasing order of importance, (a) location of flow at conventional color Doppler imaging, (b) amount of free intraperitoneal fluid, and (c) presence and thickness of septations. A scoring formula that made use of values based on the logistic regression equation had an area under the receiver operating characteristic curve of 0.98 +/- 0.01. The cutoff score with the highest accuracy had a sensitivity of 93% and specificity of 93%.

CONCLUSION

A solid component is the most statistically significant predictor of a malignant ovarian mass. A multiparameter scoring system that uses three gray-scale and one Doppler feature, developed by means of stepwise logistic regression, has high sensitivity and specificity for predicting malignancy.

Incidence and significance of free fluid on abdominal computed tomographic scan in blunt trauma

OBJECTIVE

To determine the incidence and significance of free fluid on abdominal CT in blunt trauma.

DESIGN

Retrospective chart review.

METHODS

All blunt trauma patients with an abdominal computed tomographic scan from August of 1993 to December of 1995 were identified from the trauma registry at a Level 1 trauma center. A total of 1,159 computed tomographic scans were performed; records of 18 patients were excluded for incomplete records. Official reports of computed tomographic scans were reviewed for free fluid, solid organ injury, bladder injury, and pelvic fracture.

RESULTS

Free fluid without solid organ injury was found in 3% (34 of 1141). Laparotomy was performed because of free fluid in 13 patients. There were six small bowel injuries and one diaphragm injury for a therapeutic laparotomy rate of 54%. Ten patients had trace free fluid and did not undergo laparotomy; none had a missed small bowel injury.

CONCLUSIONS

The presence of more than trace amounts of free fluid without solid organ injury in patients with blunt trauma is a strong indication for exploratory laparotomy. Patients with isolated trace amounts of free fluid can be safely observed.

Blunt bowel and mesenteric injury: diagnostic performance of CT signs

PURPOSE

Our goal was to determine the sensitivity and specificity of various CT signs of blunt bowel and mesenteric injury.

METHOD

The CT findings of 31 patients with blunt abdominal trauma were retrospectively assessed by three observers in consensus. All patients had laparotomy within 24 h of CT. The study group consisted of 19 patients with surgically proven bowel and/or mesenteric injury. The control group consisted of 12 traumatized patients who had no bowel or mesenteric injury. The CT signs assessed were presence, location, and extent of intraperitoneal fluid, extraluminal air, bowel wall thickening, bowel wall discontinuity, mesenteric streaking, and mesenteric hematoma.

RESULTS

In the 12 cases of bowel injury (9 transmural injury, 3 partial thickness injury), the CT sign of bowel wall thickening had sensitivity of 50% and specificity of 84% and the CT sign of bowel wall discontinuity had sensitivity of 58% and specificity of 95%. Extraluminal air was a specific but relatively insensitive sign of transmural bowel injury (sensitivity 44%, specificity 100%). In the 13 patients with mesenteric injuries, the CT sign of mesenteric hematoma had sensitivity of 54% and specificity of 94%. Isolated mesenteric streaking was a less specific sign of mesenteric injury (sensitivity 77%, specificity 44%). The finding of peritoneal fluid with no visible solid organ injury was a useful sign of bowel or mesenteric injury, occurring in 11 of 19 (58%) study patients and none of the controls (p < 0.001).

CONCLUSION

Bowel wall thickening, bowel wall discontinuity, extraluminal air, and mesenteric hematoma are reasonably specific CT signs of bowel and mesenteric injury following blunt abdominal trauma. The presence of a moderate to large volume of intraperitoneal fluid without visible solid organ injury is an important sign of bowel or mesenteric injury.

Sensitivity and specificity of the individual CT signs of appendicitis: experience with 200 helical appendiceal CT examinations

PURPOSE

Our goal was to determine the sensitivity, specificity, and diagnostic value of individual signs at helical appendiceal CT.

METHOD

Two hundred helical appendiceal CT scans (100 appendicitis and 100 normal appendix cases) were interpreted for individual signs of appendicitis. Scan findings were correlated with appendectomy or clinical follow-up results.

RESULTS

Individual CT signs identified and their sensitivity and specificity, respectively, included fat stranding (100%, 80%), enlarged (> 6 mm) unopacified appendix (93%, 100%), focal cecal apical thickening (69%, 100%), adenopathy (62%, 66%), appendolith(s) (44%, 100%), arrowhead sign (23%, 100%), paracolic gutter fluid (18%, 86%), abscess (11%, 100%), cecal bar (10%, 100%), extraluminal air (8%, 97%), phlegmon (7%, 99%), ileal (3%, 86%) or sigmoid (3%, 95%) wall thickening, and diffuse cecal wall thickening (0%, 91%).

CONCLUSION

Individual appendiceal CT signs of appendicitis vary in sensitivity, specificity, and thus diagnostic value. An enlarged appendix with periappendiceal fat stranding occurs in 93% of appendicitis CT cases. Less common but specific signs [cecal apical changes, appendolith(s) are usually present in the remaining appendicitis cases. Some signs seen with appendicitis (adenopathy, fat stranding, adjacent bowel wall thickening, fluid) can also be noted with alternative conditions, and in these cases normal appendix identification is the key to excluding appendicitis.

Sonographic examination of abdominal trauma by senior surgical residents

The focused ultrasound examination is assuming an important role in the evaluation of abdominal trauma. We evaluated the ability of senior surgical residents to independently use this technique. We also evaluated the efficacy of a single sonographic examination instead of serial examinations. Senior surgical residents underwent sonography instruction by two attending surgeons certified in the technique. Once proficiency was attained, a single sonographic examination was performed on patients with abdominal trauma triaged to a Level I trauma center. Residents obtained additional diagnostic studies deemed appropriate. Ultrasound results were compared with other diagnostic studies and clinical course. Sonography was performed on 518 patients between January 10, 1995 and June 30, 1996. Mechanism of injury was blunt in 92 per cent of patients and penetrating in 8 per cent. There were 22 true positives, 12 false positives, 8 false negatives, and 476 true negatives. Five of the eight false negatives were secondary to limited hollow viscus injuries with minimal associated intraperitoneal fluid. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 73.3, 97.5, 96.1, 64.7, and 98.3 per cent, respectively. The use of computed tomography and diagnostic peritoneal lavage decreased from 25 to 18 per cent and 3.2 to 0.2 per cent, respectively, as diagnostic tools. We conclude that surgical residents can competently perform trauma ultrasound. A single sonographic examination is effective and reliable. Sonography has essentially replaced diagnostic peritoneal lavage in our institution.

Diagnosis of postoperative urinary ascites using renal scintigraphy

Nuclear medicine biliary studies have been routinely used to identify bile leaks that occur after laparoscopic cholecystecomy. The use of a Tc-99m mercaptoacetyltriglycine (MAG3) renal scan to diagnose a case of urinary leakage that occurred after a laparoscopic-assisted colectomy is shown in this report. Laparoscopic surgery is widely used in place of conventional laparotomy to minimize recovery time and discomfort after surgery. The complication rate for laparoscopic colectomy has been reported as approximately 6% to 10%. In particular, ureteral leak has been reported in 2% of procedures. Ascites of unknown origin can become a diagnostic dilemma. We present a case of postoperative ascites of unknown origin that was successfully diagnosed as urinary leakage using renal scintigraphy.

Intussusception: trapped peritoneal fluid detected with US--relationship to reducibility and ischemia

PURPOSE

To determine the frequency and meaning of fluid inside the intussusception at ultrasound (US) and its relationship to irreducibility and ischemia.

MATERIALS AND METHODS

US enabled the diagnosis of intussusception in 145 cases. Shape and axial diameters of the area of fluid were determined. US-guided hydrostatic reduction was attempted in 144 cases.

RESULTS

Fluid was present in the intussusception in 20 cases (14%) and appeared on axial images as an anechoic crescent between both serosal layers of the enfolded and everted intussusceptum. No cystic structural anomaly was detected at surgery. Rates of reduction were 89% (111 of 125) in cases without fluid and 26% (five of 19) in cases with fluid (P < .001). At surgery, ischemia was absent in all 14 cases without fluid and present in 10 of 20 cases with fluid; necrosis was present in two cases with fluid. Areas of fluid greater than 14 x 5 mm, especially if associated with fluid in the dilated apex of the intussusception, were strongly related to irreducibility and ischemia (odds-likelihood ratio, 67.5).

CONCLUSION

Fluid seen inside the intussusception represented trapped peritoneal fluid. Substantial amounts of fluid were associated with irreducibility and ischemia.

Emergency physician use of ultrasonography in blunt abdominal trauma

OBJECTIVE

To evaluate the diagnostic utility of abdominal diagnostic ultrasonography (DUS) performed by emergency physicians for intraperitoneal fluid caused by blunt abdominal trauma (BAT).

METHODS

The design was a prospective, blind, observational study. During a 15-month period, a convenience sample of patients presenting to the ED with BAT necessitating CT scan of the abdomen, diagnostic peritoneal lavage (DPL), or laparotomy was studied. Scans were performed by an emergency medicine (EM) attending, or a resident supervised by an attending, using a real-time sector ultrasound scanner with a 3.5-MHz probe. Training in DUS included a 1-hour didactic session and 1 hour of practice on human volunteers. Free intraperitoneal fluid was defined as an anechoic stripe in the hepatorenal, bladder-rectal, or splenorenal space, and constituted a positive DUS study. Free intraperitoneal fluid detected on abdominal CT scan, DPL, and/or laparotomy was the criterion standard.

RESULTS

Of 110 patients scanned, 13 were excluded secondary to technical difficulty or lack of diagnostic follow-up modalities. Of the remaining 97 patients, there were 24 females and 73 males, ranging from ages 2 to 78 years. DUS detected intraperitoneal fluid in 21 subjects, including 3 false positives. There were 6 false-negative DUS examinations. DUS had a sensitivity of 75% (95% CI 53-90%), a specificity 96% of (95% CI 89-99%), and an accuracy of 91% (95% CI 83-96%). No false-positive or false-negative DUS study occurred after the first 67 cases. The mean interval for a DUS scan was 4.9 +/- 2.9 minutes, ranging from 0.5 to 16 minutes, and the mean intervals were not different between the positive and the negative studies. The accuracies of DUS were similar in the pediatric patients, 97% (95% CI 83-100%), and in the adults, 88% (95% CI 78-95%). The hepatorenal view provided the highest sensitivity as well as the least number of uninterpretable scans of the 3 DUS views.

CONCLUSION

Emergency physicians with minimal training can use DUS with fair sensitivity and good specificity and accuracy to detect free intraperitoneal fluid in both pediatric and adult BAT victims. The hepatorenal view provides the highest sensitivity for intraperitoneal fluid, although the 3-view series (with hepatorenal, bladder-rectal, and splenorenal spaces) can typically be performed within 5 minutes and may increase the specificity and accuracy.

Trauma ultrasound workshop improves physician detection of peritoneal and pericardial fluid

Hemoperitoneum represents a major indication for surgical intervention after trauma. To improve the ability of surgical residents and trauma physicians to detect intraperitoneal and pericardial fluid using ultrasound as a diagnostic modality, we conducted a focused trauma ultrasound workshop consisting of discussion of ultrasound physics, demonstration of instrumentation, review of pertinent literature, videotaped demonstration, and "hands-on" teaching of the skills utilizing live patient models. The ultrasound probes were placed in four standard locations--right and left upper quadrants, epigastrium, and Pouch of Douglas. Skills acquisition was tested by pre- and postworkshop performance on 12 sonograms (3 for each location, 6 were positive for fluid). Thirty physicians (21 residents and 9 staff: Group I) who attended the workshop were compared to 30 matched controls (Group II). The results (means +/- SD) were as follows (R = number right, I = number of "indeterminate," W = number of wrong responses out of 12, *P < 0.05 compared to Group II): [Table: see text] False positive (%) and false negative (%) decreased from 12.9 +/- 1.5 to 8.9 +/- 5.3 and 15.0 +/- 10.4 to 5.0 +/- 5.2, respectively, in Group I but did not change in Group II. Postworkshop ability to detect fluid was significantly (P < 0.05) improved, with no major differences between residents and staff. Our data suggest that these workshops can significantly improve the skills of nonradiologists in sonographic identification of pericardial and intraperitoneal fluid and should therefore be considered an essential component of ultrasound training for trauma physicians.

Low attenuation of acute traumatic hemoperitoneum on CT scans

OBJECTIVE

This study was undertaken to determine the incidence of low attenuation values in intraperitoneal hemorrhage, which could be confused with ascites.

MATERIALS AND METHODS

We retrospectively analyzed the CT scans of 42 consecutive patients with hepatic and splenic lacerations and intraperitoneal fluid after blunt abdominal trauma. Patients were excluded if they had prior peritoneal lavage, bladder or bowel injury, or low hematocrit values. Intraperitoneal fluid was categorized by the site of accumulation (perihepatic, perisplenic, Morison's pouch, paracolic gutters, or pelvis). The amount of fluid in each intraperitoneal location was categorized as small, moderate, or large. Attenuation values were obtained from each intraperitoneal site, and overall mean attenuation values were determined for each patient. We correlated the size of each fluid collection with the attenuation value. We also compared attenuation values at locations adjacent to the site of each injury with those at other intraperitoneal sites. We then evaluated technical factors that could have lowered attenuation values, including CT miscalibration, volume averaging, and beam-hardening artifacts.

RESULTS

For the 42 patients, we measured 131 separate attenuation values. Attenuation values ranged from 0 to 80 H, with attenuation of 24% of sites (32/131) measuring less than 20 H. Only 16% of sites (21/131) had attenuation values greater than 45 H. Attenuation at the remaining 78 sites (60%) measured from 20 to 45 H. All intraperitoneal locations except the pelvis had mean attenuation values significantly lower then 40 H. Mean attenuation values (determined by averaging measurements from different intraperitoneal sites) were also calculated for each patient. Only 6 (14%) of 42 patients had mean attenuation values greater than 40 H, whereas 4 (10%) of 42 patients had mean attenuation values less than 20 H. The remaining 32 patients (76%) had mean attenuation values between 21 and 40 H. Patients with hepatic lacerations showed no significant difference (p = .3509) in attenuation between perihepatic fluid and the remainder of intraperitoneal fluid. However, in patients with splenic lacerations, perisplenic fluid had a significantly higher (p = .0013) attenuation value (43 H) than did fluid at other intraperitoneal locations.

CONCLUSION

Low attenuation measurements for acute hemoperitoneum represented a common finding that was not attributable to technical factors or underlying anemia. Fluid with attenuation values less than 20 H in acute trauma should not be dismissed as ascitic fluid.

CT of intussusception in the pediatric patient: diagnosis and pitfalls

Intussusception in the pediatric patient may have a varied clinical presentation depending on its location, presence of lead point, intermittent occurrence, or underlying systemic disease. Computed tomography (CT) may be used at times in the evaluation of children with complicated presentations. The purpose of this investigation was to review the findings of CT images obtained in children with intussusception. Five patients with intussusception were diagnosed by CT at our institution between 1989 and 1994. An intraluminal mass was found in all patients. Intraluminal eccentrically located fat, as well as the target sign of alternating layers of high and low attenuation, was seen in most patients. In patients with a more long-standing process, fluid-distended loops, inflammation, and loss of tissue planes were seen and corresponded with necrosis and areas of nonviable bowel found at surgery. Finally, potential pitfalls with the layered or target appearance are discussed in the form of two patients who were initially felt to have intussusception at CT, but in whom the target appearance was later found to be due to other processes.

Sonographic diagnosis of peritoneal inclusion cysts

Peritoneal inclusion cysts have not received the attention they merit in the imaging literature. We present a series of peritoneal inclusion cysts and describe their sonographic features. Our findings lead us to encourage more conservative therapies. All seven patients in our series had pelvic pain and had undergone surgery previously. An ovary surrounded by septations and fluid was the most common finding by transvaginal sonography. Doppler examination showed low resistive flow in the septations. Conservative therapy was used in five cases with excellent results. We found that a confident diagnosis of peritoneal inclusion cysts is possible with ultrasonography. This diagnosis should encourage the use of more conservative therapy.