Sonographic examination of the appendix in acute infectious enteritis and acute appendicitis

PURPOSE: To use transabdominal sonography to determine the frequency of visualization of the adult normal appendix in patients with suspected acute infectious enteritis (AIE) compared with patients with acute appendicitis (AA) and a control group. METHODS: A total of 296 patients divided into 3 different groups underwent sonographic examination, including 120 randomly selected asymptomatic patients, 91 consecutive patients with AIE, and 85 consecutive patients with AA. In the 3 groups, visualization rate, outer appendiceal diameter, presence or absence of inflamed periappendiceal fat, and location of the appendix were recorded. RESULTS: The visualization rates of the appendix were 49.2%, 70.3%, and 96.5% for the control, AIE, and AA groups, respectively (P < 0.05). The mean +/- SD outer appendiceal diameters for the 3 groups were 4.5 +/- 1.2 mm, 4.5 +/- 1.4 mm, and 7.9 +/- 2.0 mm, respectively. The difference between outer appendiceal diameter in the control and AIE groups was not statistically significant. Periappendiceal inflamed fat was detected in all AA cases, but in none of the AIE cases. CONCLUSION: The appendix was visualized more often in patients with AIE than in the control group, although the outer appendiceal diameter of the AIE group was not significantly different from that of the normal appendix seen in the control group.     

Sonography of acute appendicitis in pregnancy

Background: Clinical evaluation of acute appendicitis is difficult in pregnant patients. Delay in diagnosis is associated with increased fetal mortality. The purpose of our study was to assess the value of sonography in the diagnosis of acute appendicitis in pregnant women. Methods: We obtained sonograms in 22 pregnant women suspected of acute appendicitis. All sonograms were performed using graded-compression to detect an enlarged appendix. The sonographic criteria for acute appendicitis were detection of a noncompressible blindended and tubular multilayered structure of maximal diameter greater than 6 mm. Results: The sonographic findings were correlated with surgical findings in seven cases and clinical follow-up in 15 cases. Acute appendicitis was diagnosed by sonography in three of 22 patients, and in all but one was confirmed by surgical and pathologic findings. In the remaining 19 patients, 15 improved on clinical follow-up; three were shown to have a normal appendix at surgery and one had focal acute inflammation at the tip of the appendix. Conclusions: Our experience suggests that graded-compression sonography is a useful procedure in pregnant patients suspected of acute appendicitis and has a similar accuracy as in nonpregnant women, especially in the first and second trimester.     

Sonography in the Evaluation of Acute Appendicitis

Objective. The purpose of this study was to evaluate the negative predictive value (NPV) of sonography in the diagnosis of acute appendicitis. Methods. Right lower quadrant sonograms of 193 patients (158 female and 35 male; age range, 3–20 years) with suspected acute appendicitis over a 1‐year period were retrospectively reviewed. Sonographic findings were graded on a 5‐point scale, ranging from a normal appendix identified (grade 1) to frankly acute appendicitis (grade 5). Sonographic findings were compared with subsequent computed tomographic (CT), surgical, and pathologic findings. The diagnostic accuracy of sonography was assessed considering surgical findings and clinical follow‐up as reference standards. Results. Forty‐nine patients (25.4%) had appendicitis on sonography, and 144 (74.6%) had negative sonographic findings. Computed tomographic scans were obtained in 51 patients (26.4%) within 4 days after sonography. These included 39 patients with negative and 12 with positive sonographic findings. Computed tomography changed the sonographic diagnosis in 10 patients: from negative to positive in 3 cases and positive to negative in 7. Forty‐three patients (22.2%) underwent surgery. The surgical findings were positive for appendicitis in 37 (86%) of the 43 patients who had surgery. Patients with negative sonographic findings who, to our knowledge, did not have subsequent CT scans or surgery were considered to have negative findings for appendicitis. Seven patients with negative sonographic findings underwent surgery and had appendicitis; therefore, 137 of 144 patients with negative sonographic findings did not have appendicitis. On the basis of these numbers, the NPV was 95.1%. Conclusions. Sonography has a high NPV and should be considered as a reasonable screening tool in the evaluation of acute appendicitis. Further imaging could be performed if clinical signs and symptoms worsen.     

Sonography of acute appendicitis in childhood: perforation versus nonperforation.

We evaluated the sonographic findings in 133 consecutive children referred for suspected appendicitis. Fifty-eight of these patients (44%) ultimately underwent surgery, with 54 of these proved to have acute appendicitis. Thirty-one (58%) of the 54 had nonperforated appendicitis, and 23 (43%) had evidence of perforation. Previously described sonographic findings that have been employed in the diagnosis of appendicitis were evaluated, with the presence or absence of these findings being compared in patients with non-perforated and perforated appendicitis. In those patients who did not undergo surgery, the following findings were documented and compared to the findings in patients with proved appendicitis: (1) an identifiable appendix and its sonographic characteristics, (2) fluid localized to the right peritoneal reflection or periappendiceal region, or both, (3) free pelvic fluid, and (4) right lower quadrant adenopathy. Our results suggest that high-resolution, real-time sonography, using graded compression, is very sensitive in the identification of acute nonperforated appendicitis. Perforated appendicitis, however, can be a more difficult diagnosis because the appendix frequently decompresses with perforation and yet may not "wall off" or form a well-defined abscess. As a result, the appendix can be very difficult to identify.     

The gas-containing appendix: potential sonographic pitfall in the diagnosis of acute appendicitis.

The presence of gas within the appendix on plain abdominal radiographs is nonspecific and may or may not be associated with acute appendicitis. This finding, however, has not previously been reported with graded compression sonography of the right lower quadrant. Gas within the appendix was identified in four of 154 patients with a visualized appendix. All four patients had surgically confirmed acute appendicitis. Diagnostic difficulties were encountered in three of these four patients. In two patients, the findings were misinterpreted as an extraluminal gas-forming periappendiceal abscess. In an additional patient, the gas-filled appendix was initially mistaken for a segment of normal terminal ileum. The gas-filled appendix is a potential pitfall in the sonographic diagnosis of acute appendicitis. However, if other diagnostic criteria are met, gas within the appendix should not preclude establishing a sonographic diagnosis of appendicitis.     

Transvaginal sonography in the diagnosis of acute appendicitis.

OBJECTIVES: To evaluate transvaginal sonography with power Doppler capacity in the diagnosis of acute appendicitis and in discriminating appendicitis from pelvic inflammatory disease. PATIENTS AND METHODS: We describe transvaginal sonographic findings of six women with acute appendicitis selected from 31 women seen in an emergency room setting for clinically suspected pelvic inflammatory disease. The study population underwent gray-scale transvaginal sonography, and specific sonographic landmark findings for acute appendicitis and pelvic inflammatory disease were used. Hyperemia of any infectious complex was identified by power Doppler. Laparoscopy was performed after transvaginal sonography and was used as the gold standard. RESULTS: Laparoscopy showed acute appendicitis in six (19%) of the 31 patients. A thick walled non-compressible gas-containing tubular structure with a diameter exceeding 6 mm was seen by transvaginal sonography in four of the six cases, consistent with uncomplicated appendicitis. A heterogeneous complex with surrounding hyperechogenic soft tissue was seen in two cases with gangrenous appendicitis. Power Doppler detected hyperemia in all six cases. Normal adnexal structures were imaged next to the inflamed appendix. The sonographic criteria consistent with acute appendicitis were clearly different from those of acute pelvic inflammatory disease. CONCLUSIONS: Transvaginal sonography provides an opportunity to distinguish between appendicitis and acute pelvic inflammatory disease. Prospective trials are needed in order to evaluate the impact of transvaginal sonography in the diagnosis of acute appendicitis.     

Torsed appendix testis: gray scale and color Doppler sonographic findings compared with normal appendix testis.

OBJECTIVE: The purpose of this study was to compare the size, shape, echogenicity, and blood flow of the appendix testis on sonography in control subjects and in patients with a torsed appendix testis and to evaluate the usefulness as well as the limitations of these criteria. METHODS: This was a retrospective analysis of 11 lesions with torsed appendix testes and 15 normal appendix testes in 12 children. The following gray scale and color Doppler sonographic features were analyzed: size, shape, echogenicity, and blood flow of the appendix testis. RESULTS: The size of the appendix testis was larger in patients with a torsed appendix testis than in the control subjects (P < .05). A spherical shape of the appendix testis was more common in patients with a torsed appendix testis (P < .05). There was no blood flow within both the torsed and normal appendix testes. However, the frequency of increased periappendiceal blood flow was higher in patients with a torsed appendix testis (P < .05). There was no significant difference in the echogenicity between the torsed and normal appendix testes. CONCLUSIONS: Gray scale and color Doppler sonography may be helpful in the diagnosis of torsion of the appendix testis. A size of 5 mm or larger, spherical shape, and increased periappendiceal blood flow are indicative of a torsed appendix testis.     

Periappendiceal hyperechoic structure on sonography: a sign of severe appendicitis.

OBJECTIVE: We retrospectively investigated the clinical importance of the periappendiceal hyperechoic structure (PHS) using sonography in patients with appendicitis, which may reflect the omentum encapsulating the inflammation or spread of inflammation over the omental and adjacent mesenteric fat. METHODS: We defined the positive finding of a PHS as a noncompressible and enlarged (>6 mm in its maximal outer diameter) appendix surrounded by the hyperechoic structure that was not visualized in the right lower quadrant on sonography. We compared this finding with surgical records and pathologic diagnosis in 25 patients who underwent an appendectomy for appendicitis. RESULTS: Of 25 patients, there were 7 patients with positive PHS findings. The positive PHS rates were 100% (2 of 2), 29% (5 of 17), and 0% (0 of 6) for gangrenous, phlegmonous, and early appendicitis, respectively. There was a statistically significant difference by the Spearman rank test. The incidence rates of perforation (57% versus 6%), macroscopic purulent exudate or abscess (57% versus 6%), and prominent adhesion to the periappendiceal tissue (100% versus 22%) were higher in the patients with positive PHS findings. CONCLUSIONS: The PHS may indicate the possibility of serious inflammation, and accurate diagnosis and appropriate treatment should be decided.     

Improved sonographic visualization of the appendix with a saline enema in children with suspected appendicitis.

OBJECTIVE: To determine whether abdominal sonography after a saline enema can identify the appendix that is not visualized at graded compression sonography in children with suspected appendicitis. METHODS: High-frequency compression sonography was prospectively performed in 120 consecutive children with suspected appendicitis; the appendix was not identified in 27 of these patients. Among the 27 patients with a nonvisualized appendix, abdominal sonography after a saline enema was performed in 12 to identify the appendix. RESULTS: Abdominal sonography after the saline enema revealed the appendix in all 12 children in whom the appendix was not visualized at graded compression sonography. A normal appendix was found in 11 children, and acute appendicitis confined to the appendiceal tip was found in 1. The appendix was located in the pelvis (n = 5), posterior to the cecum (n = 4), posterior to the ileum (n = 2), and anterior to the ileum (n = 1). The appendix could be identified by using a window of the saline-filled sigmoid colon (n = 5), saline-filled cecum (n = 4), and saline-filled terminal ileum (n = 2). CONCLUSIONS: Abdominal sonography after a saline enema is a helpful technique for depiction of the appendix that is not visible at graded compression sonography in children with suspected appendicitis. Key words: appendix, sonography; appendicitis; children, gastrointestinal tract.     

Three-dimensional sonographic evaluation of the common bile duct.

OBJECTIVE: To assess the accuracy of three-dimensional sonographic measurements of the common bile duct compared with standard two-dimensional anteroposterior measurement of the common duct. METHODS: Fifty-five consecutive patients referred for abdominal sonography underwent standard two-dimensional abdominal sonography followed by three-dimensional sonographic data acquisition of the right upper quadrant. A radiologist blinded to the results of the two-dimensional examination later measured the three-dimensional long axis anteroposterior common duct diameter and three-dimensional short axis anteroposterior and transverse common duct diameters. RESULTS: The mean average common duct diameter as measured by two-dimensional sonography (long axis anteroposterior) was 3.6 mm. The mean average common duct diameter as measured by long axis anteroposterior three-dimensional sonography was 4.1 mm. The mean average common duct diameter as measured by anteroposterior short axis three-dimensional sonography was 4.1 mm, and by transverse short axis three-dimensional sonography, it was 4.4 mm. The two-dimensional common duct measurement correlated with the long axis anteroposterior three-dimensional measurement (P < .001), the short axis anteroposterior three-dimensional measurement (P < .001), and the short axis transverse three-dimensional measurement (P < .005) by the Spearman rank order correlation coefficient test. CONCLUSIONS: Three-dimensional sonographic measurements of the common bile duct correlate highly with two-dimensional measurements, validating the use of three-dimensional sonography as a reliable method for evaluation of common bile duct size.     

Granulomatous appendicitis presenting as right lower quadrant pain: CT findings

Background: We present the computed tomographic (CT) findings of granulomatous appendicitis. Methods: Five of 652 (0.9%) patients who had undergone appendectomy for clinically suspected acute appendicitis over a 19-month period proved to have granulomatous appendicitis. One patient had surgery based on a clinical diagnosis of acute appendicitis. Four patients (three men and one woman; age range = 14–39 years) underwent abdominal CT. The CT findings were retrospectively reviewed with special attention to the appendiceal abnormalities. Results: All four patients presented with subacute clinical presentation. Enlarged appendices of 4.5 and 2 cm in diameter with thickened walls of soft tissue density were found in two patients, and periappendicular inflammatory masses were found in the other two. Enlarged mesenteric lymph nodes and right lower quadrant fat stranding was seen in all four patients. Histopathology showed numerous granulomas within the inflamed appendix. Conclusion: Radiologists should be familiar with the rare entity of granulomatous appendicitis in patients examined by CT for suspected acute appendicitis. An insidious clinical presentation with CT findings of an exceptionally large appendix and associated periappendiceal inflammatory changes should raise the possibility of granulomatous appendicitis or carcinoma or lymphoma of the appendix.     

急性阑尾炎的CT表现

目的 探讨急性阑尾炎的CT表现。方法 对68例手术、病理证实为急性阑尾炎病人的腹部CT资料进行回顾性分析，对阑尾大小、有无阑尾结石、阑尾周围及盲肠末端的改变作了观察、分析。结果 68例中61例CT诊断为急性阑尾炎，7例假阴性，CT诊断急性阑尾炎的敏感性为89．7％。急性阑尾炎的CT表现主要有阑尾增粗(76．5％)，阑尾结石(29．4％)，阑尾周围炎性改变(66．2％)，阑尾脓肿(13．2％)，蜂窝织炎(10．3％)，盲肠末端肠壁增厚(7．4％)和局部淋巴结肿大(5．9％)。结论 急性阑尾炎可出现多种CT表现，熟悉这些表现有助于提高CT诊断阑尾炎的准确性。     

Acute appendicitis and diagnostic value of sonography: A prospective study of 77 surgically proven cases

We present the results of a prospective study on 122 patients referred for suspected acute appendicitis. In total, 77 patients had surgically proven appendicitis. Of these 77 patients, sonography showed typical signs of appendicitis and/or peri-appendicular abscess in 57 cases (true positives); in the remaining 20 patients neither the inflamed appendix nor any related abnormal finding could be detected pre-operatively (false negatives). Forty-five patients were subsequently shown to have other disorders (related to the urinary or digestive tract, or to the female reproductive system); the final diagnoses were based on surgical findings in 16 patients, and on a combination of clinical, imaging and laboratory findings in the remaining 29 patients. In all these patients, no sonographic evidence of appendicitis was detected (true negatives), whereas in 33 cases the US exam was able to detect abnormal findings related to other conditions, thus suggesting a correct diagnosis. In the authors' experience, sonography has a good accuracy in diagnosing acute appendicitis. The sensitivity (75%) and specificity (100%) values were similar among the different examiners and in overall agreement with the literature data.     

多层螺旋CT三维重建对急性阑尾炎的诊断价值

目的探讨多层螺旋CT三维重建对急性阑尾炎的诊断价值。方法搜集58例临床拟诊为急性阑尾炎的病例,行多层螺旋CT检查,并经工作站进行多平面重建及曲面重建,分析其CT表现并将诊断结果与手术病理结果对照。结果58例病人中,诊断急性阑尾炎53例,升结肠癌2例,右侧腹股沟疝2例,假阴性1例。急性阑尾炎多层螺旋CT的主要征象及出现频率如下：阑尾肿大增粗（管腔直径〉6mm）占96．2％,阑尾结石占17．0％,回盲部壁增厚占30．1％,阑尾周围炎占60．4％,阑尾周围脓肿占15．1％,阑尾穿孔占9．4％。结论急性阑尾炎有典型的CT征象,多层螺旋CT三维重建图像后处理技术能多方位显示阑尾本身及其周围组织情况,在急性阑尾炎的诊断中具有较高的临床应用价值。     

Sonographic appearance of the normal appendix in adults.

OBJECTIVE: To evaluate the sonographic visualization of the normal adult appendix, a large series of sonographic images from consecutive asymptomatic patients was analyzed. METHODS: A total of 788 consecutive adult patients (402 male and 386 female; median age +/- SD, 51.1 +/- 17.2 years; range, 16-91 years) were examined by appendiceal transabdominal sonography with tissue harmonic imaging. The detection rate, outer appendiceal diameter, intraluminal content, and location of the appendix were estimated. The overall normal appendix was separated into appendix-visualized and appendix-not-visualized groups, which were then examined for the relationship with abdominal wall thickness, body mass index (in kilograms per square meter), age, and sex. RESULTS: The normal appendix was detected in 388 (49.2%) of 788 patients. The outer appendiceal diameter +/- SD was 4.27 +/- 1.2 mm (range, 1.0-11.1 mm). In 291 (75%) of the 388 patients, appendices could be depicted in the intra-luminal gas during sonography. The location of the appendix was classified according to the appendiceal tip, which was found to be abdominal in 37 (9.5%), pelvic in 291 (75%), retrocecal in 23 (6.0%), and a midline extension in 37 (9.5%). In both body mass index and abdominal wall thickness, significant differences were found between appendix-visualized and appendix-not-visualized cases (P < .05). There was no significant difference in age (P = .37) or sex (P = .23) between appendix-visualized and appendix-not-visualized cases. CONCLUSIONS: The results show that the normal adult appendix can be revealed by sonographic visualization in a large series of asymptomatic patients.     

急性阑尾炎的多层CT表现及诊断意义

目的：分析急性阑尾炎的多层螺旋CT（MSCT）征象,提高CT对急性阑尾炎诊断的准确性。材料与方法：对126例手术病理证实为急性阑尾炎的腹部多层螺旋CT进行回顾性分析,对阑尾大小、形态、位置及盲肠周围改变进行观察、分析,并把CT征象和手术结果对照。结果：126例中有120例多层螺旋CT诊断正确,CT表现包括直接征象和间接征象。直接征象为阑尾增粗、增大（85.7%）,间接征象包括阑尾周围炎（81.75%）和阑尾盲肠周围脓肿（21.4%）。有6例急性阑尾炎患者CT表现无异常征象。结论：急性阑尾炎的MSCT征象对提高诊断和鉴别诊断能力有很大帮助。     

The sonographic and color Doppler features of retained products of conception.

OBJECTIVE: The purpose of this study was to identify the sonographic features of retained products of conception (RPOCs). METHODS: Cases of clinically suspected RPOCs referred for pelvic sonography between September 1994 and July 2001 were identified. Patient age, indication, gestational age at delivery, and days postpartum were recorded and sonographic findings were reviewed. Outcomes were determined from medical records and pathology reports. RESULTS: One hundred sixty-three cases were identified. Indications for pelvic sonography included vaginal bleeding in 82 (50%), pelvic pain in 77 (47%), and fever in 55 (34%). Gestational age at delivery ranged from 14 to 43 weeks (mean, 37 weeks), and the sonographic examination was performed from 0 to 95 days postpartum (mean, 21 days). Thirty-six patients underwent surgical intervention, and 28 of these had RPOCs. The remaining 127 patients were followed clinically. An endometrial mass was the most sensitive (79%) and specific (89%) sonographic feature for RPOCs. The isolated finding of either complex fluid in the endometrial canal or a thick endometrium measuring greater than 10 mm had low sensitivity, specificity, and negative and positive predictive values. None of the patients with RPOCs had normal sonographic findings. The absence of an endometrial mass or complex fluid and an endometrial thickness of less than 10 mm were considered normal findings. Color Doppler flow was detected in the endometrium somewhat more often when RPOCs were present than in the absence of RPOCs (75% versus 40%). CONCLUSIONS: An endometrial mass is the most sensitive finding for RPOCs. If no mass or endometrial fluid is seen and the endometrial thickness is less than 10 mm, RPOCs are extremely unlikely. The absence of blood flow does not exclude the diagnosis of RPOCs.     

超声在诊断可疑急性阑尾炎中的作用

目的　探讨超声检查在诊断可疑急性阑尾炎患者中的作用。方法　 35 6例临床怀疑急性阑尾炎患者接受超声检查。采用腹前壁逐级加压探查法 ,在患者感觉最敏感点 ,寻找阑尾。或采用从侧腹向回盲部移动探头寻找阑尾。结果　35 6例临床怀疑急性阑尾炎中 ,超声确诊并被证实的急性阑尾炎有 189例 ( 5 3 % ) ,右侧输尿管结石 2 3例 ( 6 % ) ,妇科疾患者5 6例 ( 16 % ) ,阴性声像图表现者 88例 ( 2 5 % )。其声像图特征 :阑尾壁厚度范围为 2 .0～ 12 .0mm ,平均范围为 ( 5 .0± 1.2 )mm ,阑尾最大前后径 (外径 )为 4.0～ 2 7.0mm ,平均范围为 ( 5 .6± 1.1)mm。其中 4～ 6mm者 5 2例 ,>6mm者 12 7例 ,阑尾周围脂肪组织回声减低 ,有不规则低或无回声者有 2 9% ( 5 5 /189) ,阑尾周围探及淋巴结肿大者有 12 % ( 2 3/189) ,右下腹肠管液体淤积、肠蠕动加快者有 73 % ( 138/189) ,彩色多普勒超声显示阑尾壁的血供丰富者 86 % ( 16 3/189)。阑尾穿孔者 6例 ,阑尾周围脓肿者 4例。结论　急性阑尾炎时 ,超声能判断阑尾肿大程度 ,阑尾位置 ,以及其他重要并发症等。     

超声检查的阴性预测值对排除急性阑尾炎的临床应用价值

目的探讨超声检查的阴性预测值对排除急性阑尾炎的临床应用价值。方法回顾性分析临床上怀疑为急性阑尾炎的241例患者的超声声像图表现,根据声像图特点将其分为4级,再将超声检查结果与外科手术及病理结果进行比较。结果 241例患者中超声诊断阳性结果93例(2、3、4级),最终发现13例为假阳性结果;148例阴性结果(1级)中7例因临床症状及体征明显行手术治疗,病理结果均提示为急性单纯性阑尾炎。超声诊断急性阑尾炎的敏感度为91.95%(80/87),特异度为91.56%(141/154),阴性预测值为95.27%(141/148),阳性预测值为86.02%(80/93),准确性为91.70%(221/241)。结论超声检查具有较高的阴性预测值,可有效地排除阑尾炎,同时或可发现引起患者急性腹痛的其他病因,因此在急性右下腹痛患者的诊断和鉴别诊断中具有非常重要的作用。     

Acute appendicitis confined to the appendiceal tip: evaluation with graded compression sonography.

Focal appendicitis at the tip of the appendix has not been emphasized in the sonographic literature. We present the sonographic findings in four patients with pathologically confirmed acute appendicitis confined to the appendiceal tip. In all four patients, the base of the appendix had a normal appearance with maximal outer diameters measuring 4 to 6 mm. However, the inflamed tip was focally enlarged, measuring greater than 7 mm. The importance of a careful survey of the entire length of the appendix is emphasized to avoid a false-negative examination.