Sonographic Appearance of Trigger Fingers

Objective. The purpose of this study was to describe the sonographic appearance of the first annular (A1) pulley–flexor tendon complex in patients with trigger fingers. Methods. Thirty‐three trigger fingers in 33 patients were examined with a 7‐ to 15‐MHz probe. A control group consisted of 20 patients without trigger fingers. The study included systematic measurement of the thickness of the A1 pulley and a power Doppler assessment of the pulleys, tendons, and tendon sheaths. Results. Thickening and hypoechogenicity of the A1 pulley were found in all patients with trigger fingers. Measurements of A1 pulley thickness were significantly different (P < .0001) between the groups without trigger fingers (mean, 0.5 mm; range, 0.4–0.6 mm) and with trigger fingers (mean, 1.8 mm; range, 1.1–2.9 mm). Hypervascularization of the A1 pulley on power Doppler imaging was found in 91% of the trigger fingers but was never found in the healthy control group. Flexor tendinosis was found in 48% of the trigger fingers; tenosynovitis was found in 55%; and both were found in 39%. In the control group, tenosynovitis and tendinosis were not found. Conclusions. Thickening and hyper‐vascularization of the A1 pulley are the hallmarks of trigger fingers on sonography. Other frequently observed features include distal flexor tendinosis and tenosynovitis.     

Ultrasound Features of Trigger Finger: Review of the Literature

Trigger finger is a common pathologic condition of the digital pulleys and flexor tendons in the hand. The key clinical finding is a transient blockage of the digit when it is flexed with subsequent painful snapping when it is extended. Imaging is a helpful guide for establishing the severity of the disease, identifying the underlying cause, and deciding the appropriate management. This narrative review aims to recall the anatomic and pathologic bases and describe the ultrasound features of trigger finger, also including common ultrasound findings and complications after therapy. Ultrasound enables an accurate static and dynamic evaluation of trigger finger as well as a comparison with the adjacent normal digits and thus should be considered the radiologic modality of first choice for its diagnosis.     

Ultrasound‐Guided First Annular Pulley Injection for Trigger Finger

Objective. The purpose of this study was to develop an ultrasound‐guided first annular (A1) pulley injection technique for trigger finger with documentation of outcomes at 1 year. Methods. We performed a short‐axis injection into a triangle bordered by the A1 pulley, the flexor digitorum superficialis and profundus tendons and volar plate, and the distal metacarpal bone with a 10‐mg median dose of triamcinolone acetonide and 2% lidocaine. This was a prospective study of 50 of 52 consecutive trigger fingers from 24 patients recruited from a physical medicine and rehabilitation private practice. Results. All patients were available for follow‐up, with 94% (47 of 50) of fingers having complete resolution of symptoms at 6 months, 90% (37 of 41) at 1 year, 65% (17 of 26) at 18 months, and 71% (12 of 17) at 3 years after a single injection. Conclusions. Our ultrasound‐guided A1 pulley injection technique is a highly effective and minimally invasive treatment option for trigger finger with a 90% success rate at 1 year for complete resolution of symptoms after a single injection. Assuming similar patient populations, our results were statistically significant (P < .01) compared with the 56% to 57% success rates recently reported for blind injections.     

Sonographically Guided Percutaneous First Annular Pulley Release

Objective. The purpose of this study was to assess the safety of sonographically guided percutaneous finger and thumb first annular (A1) pulley releases performed using needle and hook knife techniques in an unembalmed cadaveric model. Methods. A single operator completed 50 (40 fingers and 10 thumbs) sonographically guided percutaneous A1 pulley releases in unembalmed cadavers using previously described needle and hook knife techniques and simulated local anesthesia. Half of the fingers and thumbs were completed with each technique. An experienced observer blinded to the technique dissected each specimen and assessed for neurovascular, flexor tendon, and A2 pulley injury. Completeness of release was also recorded as a secondary outcome. Results. No neurovascular or A2 pulley injury occurred in any digit, regardless of technique. No significant flexor tendon injury was seen in any digit, although minor surface scratches were visualized in 3 cases (6%; 2 knife and 1 needle). The hook knife technique was significantly more likely to result in a complete pulley release compared to the needle technique (22 of 25 [88%] versus 8 of 25 [32%]; P < .001). Conclusions. Sonographically guided percutaneous A1 pulley releases can be performed safely using previously described needle and hook knife techniques. The safety margin for thumb releases is less than that for finger releases, particularly with respect to the radial digital nerve. These cadaveric data support recently published clinical investigations recommending consideration of sonographically guided percutaneous A1 pulley release in the management of patients with a disabling trigger finger.     

Percutaneous Intrasheath Ultrasonographically Guided First Annular Pulley Release

Objective. The purpose of this study was to define in volunteers a safe area for performing a percutaneous intrasheath first annular (A1) pulley release under ultrasonographic guidance in cadavers for the treatment of trigger fingers. Methods. First, in 100 fingers of 10 volunteers, we used Doppler ultrasonography to determine the limits of the sectors enclosing structures at risk (arteries and tendons). From the synovial sheath's most volar point, we determined the relative position of the arterial walls and the distance to the flexor tendons. A scatterplot overlay of the arterial positions was digitally analyzed for determining the limits of the safe area. Second, we released the A1 pulley in 46 fingers from 5 cadavers, directing the edge of the cutting device toward our safe area from an intrasheath instrument position. The precision, safety, and efficacy of the release were evaluated by surgical exposure of the A1 and A2 pulleys and the neurovascular bundles. Results. In our volunteers, we observed a volar safe area from +6.1° to +180°. Surgical precision was good in the cadavers, with no injuries to adjacent structures, a complete release in 44 fingers (95.7%), and an incomplete release of less than 1.6 mm in 2 fingers. Conclusions. This study determined a safe volar area for aiming surgical instruments from an intrasheath position for percutaneous ultrasonographically guided A1 pulley release. The technique can be performed safely in all fingers, but we suggest being cautious in the thumb and converting the surgery to an open procedure if ultrasonographic visualization is not optimal.     

Injuries to the Collateral Ligaments of the Metacarpophalangeal and Interphalangeal Joints: Sonographic Appearance

Injuries to the collateral ligaments of the metacarpophalangeal (MCP) and interphalangeal (IP) joints are commonly encountered in both athletes and nonathletes. They require prompt evaluation to ensure proper management and prevent loss of joint motion and permanent disability. Imaging is often required to confirm the diagnosis and assess injury severity. This review article aims to provide physicians with guidelines for sonographic assessment of the collateral ligaments of the MCP and IP and related injuries. Sonographic features of ligament injuries ranging from sprains and partial‐thickness tears to full‐thickness tears are described. Specific lesions of the ulnar collateral ligament of the thumb MCP joint, such as gamekeeper's thumb, skier's thumb, and Stener lesions, are also included. In conclusion, sonography is effective in evaluating the collateral ligaments of the MCP and IP joints and related injuries and represents a valuable tool for diagnosis.     

Sonographic Analyses of Pulley and Flexor Tendon in Idiopathic Trigger Finger with Interphalangeal Joint Contracture

This study investigated the sonographic appearance of the pulley and flexor tendon in idiopathic trigger finger in correlation with the contracture of the interphalangeal (IP) joint in the thumb or proximal IP (PIP) joint in the other digits. Sonographic measurements using axial images were performed in 177 affected digits including 17 thumbs and 34 other digits judged to have IP or PIP joint contracture and 77 contralateral control digits. The A1 pulley of the contracture group was significantly thicker than that of the non-contracture group in all digits, whereas the flexor tendon was thicker only in digits other than the thumb. In the analysis using calculated cut-off values, A1 pulley thickening in the thumb and A1 pulley and flexor tendon thickening in the other digits showed statistically significant correlations with IP or PIP joint contracture. This study sonographically confirmed previous reports showing that enlargement of the flexor tendons contribute to the pathogenesis of PIP joint contracture.     

Sonographic Features of Sinus Pericranii in 4 Pediatric Patients

Sinus pericranii is a rare venous anomaly, which shows abnormal communication between the intracranial and extracranial venous systems. Sonograms of sinus pericranii in 4 children were retrospectively reviewed to evaluate the following imaging findings: the overall sonographic appearance, change in size and shape, Doppler flow pattern, and associated anomalies. All 4 patients had irregularly shaped anechoic lesions with lobulating and bulging contours. They all showed intracranial and extracranial venous communication through a calvarial defect. Two patients had changes in the sizes and shapes of the lesions, and 2 patients had bidirectional turbulent flow on Doppler images. Two patients had isolated sinus pericranii, and the other 2 were associated with Crouzon syndrome. By identifying a venous scalp mass with intracranial and extracranial venous communication and changes in its size, shape, and venous flow pattern, radiologists will be able to make a definitive diagnosis of sinus pericranii by using gray scale and Doppler sonography.     

Sonographic Findings of Acute Vasitis

Objective. The purpose of this study was to describe the sonographic findings of acute vasitis. Methods. This was a retrospective analysis of 12 cases of acute vasitis. The following gray scale and color Doppler sonographic features were analyzed: location, echogenicity of the lesion, presence of hydrocele, epididymal involvement, and blood flow within the lesion. Results. Of the 12 patients, 10 had acute vasitis in the scrotal segment; 1 had acute vasitis in the suprascrotal segment; and 1 had acute vasitis in both the scrotal and suprascrotal segments. The sonographic finding for acute vasitis of the scrotal segment was a heterogeneously hypoechoic appearance of the vas deferens (n = 11). The vas deferens was thickened (6.4 mm in diameter) in the 2 patients with suprascrotal involvement; it was heterogeneously hypoechoic in 1 and had a normal appearance in the other. On color Doppler sonography, the degree of blood flow was increased in all of the cases. Of the 12 patients, 11 had inflammation of the epididymis. Conclusions. Acute vasitis usually presents with infection combined with acute epididymitis, and it usually appears as a heterogeneously hypoechoic lesion in the scrotal segment, suprascrotal segment, or both.     

Sonographic Appearances of Desmoid Tumors

The medical records of 16 patients (9 female and 7 male; age range, 5–66 years) with 24 lesions that had a histologic diagnosis of desmoid tumors were reviewed at our institution. Six cases were extra‐abdominal, 4 intra‐abdominal, and 6 in the abdominal wall. Lesions ranged from 1.5 to 18.0 cm in diameter (mean, 6.8 cm). All lesions were solid masses, which appeared hypoechoic, isoechoic, or hyperechoic with homogeneous or heterogeneous echogenicity. Posterior acoustic enhancement was seen in 18 lesions. No lesions showed central necrosis. Most lesions had substantial flow and high resistive index values (>0.70). Sonography can show a desmoid tumor's site, size, contour, margin, echogenicity, homogeneity, vascularity, and resistive index value in detail.     

Sonographic Findings of Inguinal Endometriosis

Objective. The purpose of this series was to describe the sonographic findings of inguinal endometriosis. Methods. This was a retrospective analysis of 3 cases of inguinal endometriosis. The following gray scale and color Doppler sonographic features were analyzed: size, shape, echogenicity, and blood flow within inguinal endometriosis. Results. The size of inguinal endometriosis ranged from 3.1 to 4.2 cm (mean, 3.7 cm). All 3 cases were cystic lesions. Two of 3 cases were lesions with internal septa. On color Doppler sonography, 1 of the 3 cases showed a few flow signals within the lesion, whereas in 2 of the 3 lesions, no blood flow could be identified within the lesions. Conclusions. Although the sonographic features of inguinal endometriosis may be variable, endometriosis should be included in the differential diagnosis when unilocular and multilocular cystic masses are seen on sonography.     

Sonographic Findings of Subcutaneous Sarcoidosis in 3 Cases

Subcutaneous sarcoidosis occurs infrequently among cases of cutaneous sarcoidosis. To our knowledge, few studies have described the sonographic characteristics of subcutaneous sarcoidosis. Here we report the sonographic characteristics of 3 cases of this condition. Our results revealed 4 features: (1) an irregular hypoechoic appearance, (2) heterogeneous echogenicity, (3) perilesional hyperechoic changes, and (4) abnormal Doppler signals. Sonography is a rapid, simple, and noninvasive procedure that is useful for initial evaluation of granulomatous lesions such as subcutaneous sarcoidosis.     

Sonographic Features of Gynecomastia

Objective. The purpose of this study was to identify sonographic features of gynecomastia. Methods. .A retrospective analysis was performed on all male patients with breast symptoms imaged with breast sonography over a 5‐year period. Breast sonograms in 158 men were jointly reviewed by 3 investigators. Sonograms were assessed for the presence or absence of a mass: (1) if mass present, (a) location of the mass, (b) vascularity, (c), axis, (d) appearance of posterior tissues, and (e) tissue echo texture; and (2) if mass absent, anteroposterior (AP) depth at the nipple (increased if >1 cm). Results. Of the 237 men with breast symptoms, 79 with only mammography were excluded. Of the 158 who had sonography with or without mammography, 5 without gynecomastia were also excluded. A total of 153 men included in the study presented with pain (n = 38), a lump (n = 95), both pain and a lump (n = 17), or nipple discharge (n = 3). Nine of 153 with gynecomastia had a biopsy. A total of 219 sonographic examinations were performed, which revealed 73 masses (33%): 20 (27%) nodular, 20 (27%) poorly defined, and 33 (45%) flame shaped. All masses were retroareolar, with 57 (78%) hypoechoic, 54 (73%) avascular, 60 (82%) parallel to the chest wall, and 47 (64%) without posterior enhancement or shadowing. Of the 146 without masses (67%), 141 (97%) had increased AP depth at the nipple. Conclusions. Gynecomastia is a clinical diagnosis, and mammography is the primary imaging modality when indicated. However, if sonography is used when mammography is declined or when mammography is inconclusive, it is important to recognize the various described patterns of gynecomastia to avoid unnecessary biopsy based on sonographic findings.     

Doppler Sonographic Findings in an Experimental Rabbit Model of Necrotizing Enterocolitis

Objective. The purpose of this study was to examine the clinical applicability of Doppler sonography by evaluating Doppler sonographic findings in an experimental rabbit model of necrotizing enterocolitis (NEC). Methods. Necrotizing enterocolitis was experimentally induced using a combination of endotoxin, hypoxia, and cold stress in 23 rabbits. Doppler sonography was performed to obtain the Doppler spectrum of the superior mesenteric artery. From the flow profile, the peak systolic velocity (PSV) and resistive index (RI) were calculated at 5 time sessions: initial and 1 to 2, 3 to 4, 5 to 6, and 20 to 24 hours. Animals were divided into 2 groups based on pathologic NEC scores (NEC‐positive [NEC+] group versus NEC‐negative [NEC?] group). Differences between the groups with regard to RI and PSV values were evaluated for each time session. Results. Comparison of RI and PSV values between the NEC+ and NEC? groups revealed a significant increase in the PSV in the NEC+ group during the 1‐ to 2‐hour session (P = .0199). Comparison of RI and PSV differences revealed a significant increase in RI and PSV differences in the NEC+ group during the 1‐ to 2‐hour session (P = .0095 and .0013, respectively). In the other time sessions, there was no difference between the groups. Conclusions. The NEC+ group showed a significant increase in the PSV and RI during the 1‐ to 2‐hour period.     

Sonographic appearance of fallopian tube carcinoma

Fallopian tube carcinoma is the least common of gynecological malignancies. We report the case of a 56-year-old woman who presented with a 2 1/2-year history of intermittent vaginal bleeding and lower abdominal pain. Transvaginal sonography revealed a cystic lesion of the fallopian tube with papillary projections, distinct from the ovary and uterus. Doppler examination showed low vascular impedance (resistance index 0.50, pulsatility index 0.80). The suspicion of tubal malignancy was confirmed at surgery.