Retroperitoneal cyst: sonographic findings

Background: Retroperitoneal cyst (RC) is a relatively rare disease, and its sonographic (US) findings have not been analyzed sufficiently. Methods: We studied US findings of five patients with RC, with special attention to location, size, shape, internal echoes, the presence or absence of lateral shadowing, and the mode of back echoes. Results: In all cases, the cyst was situated behind (four cases) or lateral to (one case) the pancreas: behind or lateral to the pancreatic head in two cases, behind the pancreatic body in one case, and behind the pancreatic tail in two cases. Four cases showed a round mass (three cases) or multiple round mass (one case). Internal echoes were present in those cases and showed a “pseudo-solid” pattern. In those cases, M-mode US confirmed the movement of those internal echoes. In the remaining case, the lesion was imaged as an irregularly shaped multilocular mass. No case showed posterior echo enhancement, and no case showed lateral shadowing. No blood flow signals from the lesion were seen. Conclusion: Unlike ordinary cysts, RC usually is imaged as a round mass behind the pancreas, with dense internal echoes without lateral shadowing or posterior echo enhancement, which presents a “pseudo-solid” pattern. A diagnosis of RC should be considered when encountering a mass with such US findings. Received: 6 June 2001/Accepted: 25 July 2001     

Sonography of ovarian fibromas/thecomas

The sonographic findings in 14 patients with ovarian fibromas/thecomas are described. A broad spectrum of sonographic features are presented and include hypoechoic mass with posterior shadowing (two cases); anechoic mass with good through transmission (with septations, two cases; without septations, four cases), echogenic mass with well-defined posterior wall (three cases); calcified mass (two cases); mixed echogenicity mass (one case). The pattern of a hypoechoic adnexal mass with acoustic shadowing should still suggest a fibroma/thecoma, but in most cases the appearance is nonspecific.     

Mesenteric cyst: sonographic findings

Background: Mesenteric cyst (MC) is a relatively rare disease, and its sonographic characteristics have not been sufficiently analyzed. Methods: We studied the sonographic findings of eight patients with MC, with attention paid to its size, shape, internal echoes, and especially the presence or absence of lateral shadowing and the mode of back echoes. In four cases, the sound velocity and acoustic impedance of cystic fluid were also measured. The mode of blood flow was evaluated by color Doppler sonography. Results: Six cases showed an oval or comma-shaped mass. Internal echoes were present in six cases, and two of them showed a pseudosolid pattern. In these cases, M-mode sonography confirmed the movement of these internal echoes. Only one case showed a posterior echo enhancement, and no case showed lateral shadowing. Sound velocity measured in four cases was 1515–1537 m/s, with an acoustic impedance of 1.550–1.576 kg/m²/s. No blood flow signals were obtained from the lesion. Conclusion: MC exhibits so many patterns on ultrasound that we should consider the possibility of MC when encountering an avascular oval mesenteric mass. Received: 30 August 1999/Accepted: 6 October 1999     

Sonographic features of breast hamartomas.

OBJECTIVE: The purpose of this study was to elucidate the sonographic characteristics of breast hamartomas. METHODS: Data and sonographic images of 14 breast hamartomas were retrospectively reviewed. RESULTS: All patients had clinically palpable lumps. The median patient age was 39.5 years (range, 24-60 years). Eleven (78.6%) tumors occurred in the right breast, and 3 (21.4%) were in the left. The median tumor size measured by sonography was 2.8 cm (range, 1.2-4.9 cm). The median longest transverse dimension-anteroposterior diameter ratio of the tumors was 2.44 (range, 1.52-3.73). All tumors were oval and compressible with transducer pressure. Thirteen (92.9%) tumors were well circumscribed with smooth tumor margins, and 1 (7.1%) had indistinct margins. The internal echo texture was hyperechoic in 6 (42.9%), mixed (heterogeneous) echogenicity in 5 (35.7%), and isoechoic in 3 (21.4%). Four (28.6%) tumors had echogenic halos, and 2 (14.3%) had anechoic halos. Ten (71.4%) tumors had no retrotumor acoustic phenomena. Two (14.3%) had bilateral edge shadowing; 1 (7.1%) had posterior enhancement; and 1 (7.1%) had a mixture of enhancement and shadowing. CONCLUSIONS: Breast hamartomas were well-circumscribed, solid, oval tumors without intratumor microcalcification. The internal echo texture of most hamartomas is either hyperechoic or composed of mixed echogenicity. Retrotumor acoustic phenomena were absent in most hamartomas.     

Appendiceal mucocele: sonographic findings

Background: Appendiceal mucocele (AM) is a relatively rare disease, and its sonograms (US) have not been sufficiently analyzed. Methods: We studied the US findings of five patients with AM, with special attention to AM size, shape, internal echoes, and the mode of back echoes. Results: All five cases showed an elongated mass in the lower right abdomen. Internal echoes were present in all cases and M-mode US confirmed the movement of those echoes. The echogenecity of the lesion changed according to the frequency of the transducer used. Only one case showed posterior echo enhancement, and no case showed lateral shadowing. Conclusion: AM appears as an elongated echo-poor mass without posterior echo enhancement. The cyst wall is less distinct than what one would expect for a cyst. When encountering such a mass in the lower right abdomen, one should strongly suspect an AM. In such cases, appropriate diagnostic and therapeutic strategies are especially necessary to prevent rupture that results in development of pseudomyxoma peritonei. Received: 7 November 2001/Accepted: 5 December 2001     

Artifactual echoes in B-mode images due to multiple scattering

In B-mode images, echoes, which appear to arise from inherently anechoic regions due to scattering from neighbouring echogenic regions, can be considered artifactual. We have observed multiple scatter contributions to such artifactual echoes in images of plane boundaries between random scattering phantoms and anechoic regions. For the strongest scattering phantom studied, multiple scatter echoes were 3-9% of the average phantom signal using two sharply focused transducers, an annular array in pulse echo mode, and an annular array/cone hybrid. Multiple scatter was less than 5% for a conventional transducer. Echo amplitudes were also measured in normal excised human liver and breast tissue. It was estimated that artifactual echoes due to multiple scatter would be negligible in B-mode images of liver. However, for breast imaging, the level of artifactual echoes was estimated to be similar to that found for our strongest scattering phantom.     

Renal cyst completely filled with milk of calcium on ct appears as a simple cyst on sonography

Milk of calcium within a renal cyst typically layers in the dependent aspect of the cyst and appears echogenic with posterior shadowing and reverberation echoes on sonography. We present a rare case of a renal cyst completely filled with milk of calcium, which appeared sonolucent with enhanced through transmission. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 42 :100–102, 2014     

Sonographic appearances of galactoceles.

PURPOSE: The aim of this study was to investigate and summarize the sonographic appearances of galactoceles. METHODS: We retrospectively reviewed the sonograms and clinical records of 10 patients with galactoceles who had been examined over a 5-year period to evaluate breast lumps that had occurred during lactation or the puerperium. RESULTS: Sonograms from all patients showed well-defined lesions with thin, echogenic walls. The internal appearances of the lesions included homogeneous contents with medium-level echoes in 6 patients and heterogeneous contents with fluid clefts and anechoic rims in 4 patients. Focal echogenic areas with distal shadowing were seen in 2 patients. Most of the lesions showed some distal acoustic enhancement, depending on the internal contents. The diagnosis of a galactocele was established by needle aspiration in 9 patients and by excision biopsy in 1 patient. Needle aspiration alone was therapeutic in 8 patients. CONCLUSIONS: Galactoceles can have a wide range of sonographic appearances and can mimic other lesions of the breast, both benign and malignant. The clues to the diagnosis are recent childbirth and lactation and the presence of a well-defined lesion with some distal acoustic enhancement. Needle aspiration of the lesion is both a diagnostic tool and an effective treatment in most patients with galactoceles.     

The spectrum of sonographic findings in endometriomas

The sonographic features of 40 pathologically proven endometriomas in 32 patients were reviewed to evaluate their sonographic spectrum. Acoustic enhancement was present in 88% and indeterminate in 10% due to technical factors. With respect to internal echo texture, the majority of endometriomas were predominantly anechoic (80%): 7 were totally anechoic; 4 contained septations; 12 contained scattered internal echoes, with or without septations; and 9 contained dependent echoes, with or without septations. Seven endometriomas contained diffuse, low-level internal echoes and were considered hypoechoic, but still fluid-containing masses. Only 1 was echogenic. The overall appearance frequently simulated that of hemorrhagic ovarian cyst, but in some cases endometriomas resembled tubo-ovarian abscess, cystadenoma/cystadenocarcinoma, or ectopic pregnancy.     

The common ultrasonographic features of pilomatricoma.

OBJECTIVES: The purpose of this series was to describe typical ultrasonographic features of 20 cases of pilomatricoma and to improve its diagnostic rate with the use of an ultrasonographic approach. METHODS: For 20 pilomatricomas in 19 patients with preoperative ultrasonography from 1995 to 2004, we reviewed age, sex, symptoms, duration, referring clinician, and tumor sites. The ultrasonographic findings were retrospectively analyzed for tumor location, shape, size, margin, echo texture, echogenicity, presence, amount, and shape of calcification, presence of a hypoechoic rim, and Doppler flow pattern. RESULTS: The mean age of the 19 patients was 6.9 years (range, 1-21 years), and the female-male ratio was 1.1:1. Patients had a painful palpable mass in 10 cases (50%). Nine lesions occurred in the neck, 5 in the cheek, 2 in the preauricular region, and 4 in the extremity. All tumors were located in the subcutaneous layer. The mean size of the tumors was 13.4 mm. Fourteen pilomatricomas (70%) appeared as well-defined oval masses. Tumors were heterogeneously hyperechoic in 80% of cases. All tumors had internal echogenic foci. A hypoechoic rim was seen in 17 cases (85%). Doppler flow signals were observed in the peripheral region in 14 cases (70%). A correct preoperative diagnosis was made in 33% on the basis of clinical findings and in 76% by ultrasonography. CONCLUSIONS: Diagnosis of pilomatricoma should be considered when a well-defined mass with inner echogenic foci and a peripheral hypoechoic rim or a completely echogenic mass with strong posterior acoustic shadowing in the subcutaneous layer of the head, neck, or extremity is found on ultrasonography.     

Gas as a contrast agent and diagnostic aid in abdominal sonography.

Gas has a characteristic ultrasound pattern, usually recognized as an area of focal dense echogenicity with acoustic shadowing. It often contains reverberation echoes. Sonographers should be familiar with this pattern and should suspect underlying disease when gas is demonstrated in abnormal or unusual locations. The authors have collected 18 cases; four representative cases are presented to illustrate this principle.     

Sonography of wrist ganglion cysts: variable and noncystic appearances.

OBJECTIVE: In our clinical practice, we have noted wrist ganglion cysts that do not fulfill the criteria for simple cysts. This study retrospectively evaluated the sonographic features of wrist ganglia. METHODS: After Institutional Review Board approval, medical records from 1993 through 2003 were searched using International Classification of Diseases, Ninth Revision codes and key words, and sonography log books from 2000 through 2004 were reviewed, which identified 20 wrist ganglion cysts in 16 patients that were proven at surgery or aspiration. A retrospective review of sonographic images was carried out by 2 musculoskeletal radiologists by consensus. Images were evaluated for cyst location, volume, largest dimension, joint or tendon extension, echogenicity, septations, internal echogenicity, posterior acoustic enhancement, margins, lobularity, and vascularity. RESULTS: Of the 20 wrist ganglia, 15 were volar (10 between the flexor carpi radialis and the radial artery), and 5 were dorsal (2 over the scapholunate ligament). The mean volume was 2081 mm3 (range, 90-15,000 mm3), and the mean largest dimension was 17.3 mm (range, 7-30 mm). Seven volar ganglia showed joint communication. Ten ganglia were anechoic; 7 were hypoechoic; and 3 had anechoic and hypoechoic areas. Eight had septations; 8 had internal echogenic areas; 15 had posterior acoustic enhancement; 13 had well-defined margins; 12 were lobular; and none were vascular. Cysts that were anechoic (P < .0001) or with posterior acoustic enhancement (P = .04) were significantly larger than those that were hypoechoic or without posterior acoustic enhancement. CONCLUSIONS: Small wrist ganglion cysts (< or = 10 mm in the mean largest dimension) often appear hypoechoic without posterior acoustic enhancement and do not fulfill the criteria for a simple cyst.     

Review of artifacts associated with transrectal ultrasound: Understanding,recognition, and prevention of misinterpretation

Artifacts are inadequate representations of the structures being imaged. Transrectal ultrasound (TRUS) used for evaluating rectal tumors has its own, unique spectrum of artifacts such as (1) pseudomasses (beam thickness: imaging of rectal folds; mirror image: reflection at an intraluminal fluid level); (2) inadequate size of the lesion (mirror image or grating lobes); (3) simulation of malignant infiltration (beam thickness, attenuation or refraction); (4) incomplete field of view (shadowing; reverberation or mirror-image); (5) confusing echo patterns (side lobe artifacts or mirror image: reflection at the balloon surface). The understanding of the physical properties of ultrasound is the basis for the recognition of these artifacts and prevention of misinterpretation. We present a review of these artifacts and their causes. © 1995 John Wiley & Sons, Inc.     

Galactoceles mimicking suspicious solid masses on sonography.

OBJECTIVE: The purpose of this study was to evaluate the sonographic appearance of a galactocele that can sonographically mimic a suspicious solid mass and to differentiate between a galactocele and a solid mass. METHODS: From September 2002 to February 2004, 33 galactoceles classified as Breast Imaging Reporting and Data System category 4 were included. They were all confirmed by sonographically guided core biopsies. Their sonographic imaging and clinical findings were reviewed retrospectively. RESULTS: The lesions had a round or irregular shape in 26 patients (78.8%), a noncircumscribed margin in 31 (93.9%), a nonparallel orientation in 22 (66%), and posterior shadowing in 13 (39.4%). Twenty-five nodules (75.8%) had internal hypoechogenicity or mixed echogenicity. Twenty-nine (87.9%) of 33 lesions showed a relatively sharp convex echogenic rim on the anterior or posterior wall. CONCLUSIONS: Galactoceles have various sonographic findings, many of which are similar to those of suspicious solid breast masses. However, there is a tendency for a galactocele to appear as a small, round hypoechoic nodule with an indistinct or microlobulated margin and mild posterior shadowing. It is helpful to search for a partial anterior or posterior echogenic rim to identify a galactocele.     

原发性乳腺淋巴瘤的临床、病理及影像学特点

原发性乳腺淋巴瘤极少见,其治疗方法与乳腺癌不同,预后比乳腺癌差。该疾病的临床特点及影像学表现与乳腺癌有很大重叠,主要依靠病理诊断和分型。弥漫性大B细胞淋巴瘤是最常见的病理类型。细针针吸细胞学检查的准确率高于冷冻检查,但两者均难以完全正确诊断。临床上患者通常表现为无痛性肿块,为单个或多结节,少数患者呈弥漫浸润使乳房变硬,局部皮肤受累。原发性乳腺淋巴瘤X线表现大致可分为结节或肿块型及致密浸润型,钙化、毛刺、乳头内陷等罕见。其超声表现复杂多样,可表现为低回声或高回声,部分呈类囊肿样极低回声,伴后方回声增强或无改变,内部血流较丰富。关于乳腺淋巴瘤MRI表现的文献主要见于个案报道,表现为T1WI低信号,T2WI稍高信号,增强扫描早期明显强化,曲线以流出型多见。MRI检查在乳腺淋巴瘤诊断中的作用还不确定。     

Ciliated hepatic foregut cyst: case report with an emphasis on US findings

Ciliated hepatic foregut cyst (CHFC) is a rare mass, and its medical imaging findings are seldom reported. We present a histologically proven case of CHFC. The patient was asymptomatic, and a mass was found incidentally by sonography (US) in segment IV. The lesion was almost anechoic on fundamental US but filled with dense echoes with distinct posterior echo enhancement on second harmonic imaging. The lesion was avascular on color Doppler US and angiography. Thus, when US detects a mass in segment IV, the possibility of a CHFC should be considered regardless of the US results.     

Echogenic forms of hydatid cysts: sonographic diagnosis

Of 167 patients with abdominal hydatidosis, 29 showed a total of 36 hydatid cysts in which ultrasound demonstrated an overall echogenic appearance. The following ultrasound characteristics of an abdominal mass suggest the diagnosis of hydatid cyst: round or oval shape, well-defined borders, partial wall calcification, peripheral cystic structures, internal echogenic linear formations, snow storm and/or hyperechogenic internal echo pattern, and posterior acoustic enhancement. A comparative study with computed tomography has also been carried out in 10 of these cysts. Pathologic correlation in most cases allows us to postulate that this appearance represents an overly mature, probably ruptured, hydatid cyst.     

New observations in the sonographic evaluation of intrauterine contraceptive devices

The in vitro sonographic appearance of the four currently available intrauterine contraceptive devices (IUDs) now used in the United States and Canada were analyzed and compared with in vivo scans. While plastic IUD limbs demonstrated entrance-exit echoes in all scan planes, copper IUDs showed posterior reverberation when optimal gain settings were used. Regardless of the transducer used, posterior acoustic shadowing was only seen when IUD limbs were scanned perpendicular to their long axis and at the junction of long and short limbs. The authors feel that these refined ultrasound characteristics will be helpful in accurately identifying IUDs within the uterus.     

乳腺脂肪坏死的声像图特点

目的：探讨乳腺脂肪坏死的超声影像学特征。方法：对我院1994年4月至2001年12月间诊治的30例乳腺脂肪坏死超声影像特点进行回顾性分析，所有患者均经手术切除获得病理组织学诊断。结果：乳腺脂肪坏死的声像图表现分为：皮下型：9例（30％）位于皮下的脂肪组织呈增强的中等回声区。此型误诊率为33%(3/9)。腺体型：21例（70％）病变位于腺体内，声像图表现为：（1）62％（13／21）呈低回声，后方回声增强或无改变；（2）24％（5／21）呈无回声，后方回声增强；（3）5％（1／21）呈无回声，后方回声衰减；（4）5％（1／21）呈无回声，腔内壁呈高回声结节，后方回声增强；（5）5％（1／21）声像图正常。此型误诊率达76％（19／21）。结论：了解乳腺脂肪坏死的特征性声像图，对诊断此病具有重要价值。     

Sonographic features with histologic correlation in two cases of palpable breast cancer after breast augmentation by liquid silicone injection

Sonography is rarely used to evaluate the breasts in patients who have undergone liquid silicone injections for breast augmentation because strong acoustic shadowing from the resulting silicone granulomas hampers the examination. We report on 2 patients who underwent silicone injection 18 and 20 years earlier and in whom breast cancers (1 invasive ductal carcinoma and 1 carcinosarcoma) were diagnosed by sonographically guided core-needle biopsy. On sonograms, both cancers had a peripheral hypoechoic rim surrounding an echogenic center. The echogenic center corresponded histologically to a silicone granuloma in 1 patient and to a large area of necrosis in the other; the hypoechoic rims corresponded to areas of cancer in both patients.