Ultrasonography of a subungual glomus tumour

Current Topics in Nail Surgery

Background:

Nail surgery can be performed in an office-based dermatology practice with a limited amount of specialized equipment and training. Several excellent reviews have been published in recent years that detail the techniques of nail surgery for both the novice and the experienced practitioner.

Objective:

In this article recent developments in nail surgery are discussed. Topics that are treated include the general principles of nail surgery, including epidemiologic issues, studies of nail anatomy, instrumentation, and anesthesia. The reconstruction of injuries and congenital defects involving the nail is explained, and the role of the hand surgeon clarified. Appropriate removal of tumours and cysts is considered, with special attention to the management of malignant lesions. The controversy regarding more or less conservative management of melanonychia striata is addressed, and the need for early diagnosis of subungual melanoma is emphasized. Other topics are surgical management of ingrown nails and onychomycosis. Newer areas of nail surgery, such as laser surgery of the nail, psycho-dermatology of the nail, and the role of primary care physicians in simple nail surgery are also examined.

Magnetic Resonance Imaging in the Diagnosis of Glomus Tumours of the Hand

This paper studies the sensitivity, specificity and predictive values of MRI in the diagnosis of glomus tumours of the hand and investigates the final diagnosis and outcome in cases with false positive or negative imaging tests. A total of 42 cases with the clinical diagnosis of a glomus tumour were included in the study. All patients underwent MRI and the results of MRI were correlated with the final histological diagnosis of the excised lesion. MRI had a sensitivity of 90%, a specificity of 50%, a positive predictive value of 97% and a negative predictive value of 20%. The four cases in which the MRI was negative all proved histologically to be glomus tumours. All four tumours were small (2–3 mm in diameter) and the lack of delineation of the lesions by MRI was attributed to their small size. Despite negative MRIs, surgical exploration identified the glomus tumours. Based on the results of the current study and the cost of MRI, the senior author has stopped ordering pre-operative MRIs in patients clinically diagnosed with a glomus tumour.

Three cases of subungual glomus tumours of the fingers - a case series

Subungual glomus tumours are rare tumours (2% of all hand tumours) presenting with excruciating pin point pain under the nail which is often misdiagnosed. Diagnosis is often always clinical. Here, we report the case of three patients who had subungual glomus tumour not diagnosed earlier for many years.

Role of high-variable frequency ultrasound in preoperative diagnosis of glomus tumors: a pilot study

BACKGROUND

Accurate preoperative imaging of glomus tumors improves the outcome of surgery. Currently, MRI is frequently recommended for preoperative assessment although this requires the use of intravenous contrast media and may be less efficient at detecting tumors <3 mm in diameter. Recent developments in high-variable frequency ultrasound (HVFUS) mean re-evaluation of the possible role of ultrasound in the preoperative detection of glomus tumors appears appropriate.

OBJECTIVE

To assess the capabilities of contemporary HVFUS in relation to preoperative detection and characterization of glomus tumors.

METHODS

Seven patients (all women, aged 38-66 years, mean age 51.3 years) suspected on clinical grounds of having a glomus tumor were evaluated with high-resolution color Doppler ultrasound using a compact linear probe that varies from 7 to 15 MHz in frequency. The results were compared with histology.

RESULTS

The tumors and their exact location were identified in all cases. The tumors appeared as hypoechoic nodules with high vascularity in the nail bed, together with remodeling of the underlying bone. Small tumors (0.9 mm depth) were also identified. Arterial flow was identified inside all tumors. Peak systolic velocity varied greatly, but the mean was 11.3 +/- 9.1 cm/sec (range: 3.7-26.1 cm/sec).

CONCLUSION

Recent developments in HVFUS have made it possible to identify small glomus tumors in real time and with high resolution. The procedure does not require administration of intravenous contrast media and provides good information about lesional blood flow and the surrounding structures. These results suggest that HVFUS may play a larger role in the preoperative assessment of glomus tumors in the future.

Nail thickness measurements using optical coherence tomography and 20-MHz ultrasonography

BACKGROUND

Nail diseases are often troubling to the patient and may present a diagnostic challenge to the dermatologist. Biopsies from the nail may be required although often perceived uncomfortable by the patient and potentially scarring. Noninvasive technologies are therefore of particular interest in the study of nails. Optical coherence tomography (OCT) is an optical imaging modality which may provide improved data.

OBJECTIVES

This study evaluates nail morphology and thickness in OCT images in comparison with high-frequency ultrasound (HFUS) imaging of the nail.

METHODS

Ten healthy volunteers were recruited for imaging and nail measurements; OCT and HFUS images were compared qualitatively. Nail thickness measurements with four different techniques were compared: ultrasound, OCT, polarization-sensitive (PS) OCT and callipers. The OCT system was developed at Risoe National Laboratory, Denmark. A commercially available 20-MHz ultrasound system (Dermascan; Cortex Technology, Hadsund, Denmark) was used.

RESULTS

In standard OCT the nail plate appeared as a layered structure containing a varying number of horizontal homogeneous bands of varying intensity and thickness. PS-OCT images of the nail plate also showed a layered structure. The refractive index of the nail was 1.47 +/- 0.09. OCT and PS-OCT had low coefficients of variation, 6.31 and 6.53, respectively, compared with other methods: HFUS 12.70 and callipers 14.03.

CONCLUSION

PS-OCT has to our knowledge not been applied to OCT analysis of the nail, and offers some advantages in separation of the nail bed from the nail plate.

Ultrasound imaging of nails

The nail apparatus contains tissues of various echogenicities and is thus well suited for ultrasound examination. Furthermore, ultrasonography is widely available and non-invasive and may therefore be used for longitudinal studies of tissues and diseases. Characteristic ultrasound pictures can be seen in psoriasis, cysts, vascular abnormalities,and other nail diseases. Ultrasound examination can visualize and quantify morphologic and functional aspects of nail biology.

Subungual glomus tumor diagnosis based on imaging

A 50-year-old woman had had tenderness of the nail bed of the right thumb for more than 20 years. For the previous 5 or 6 years, she had also had attacks of pain with exposure to cold, and deformity of the right thumb nail plate began to appear. There was red discoloration on the proximal aspect of the nail bed, and a longitudinal fissure on the distal aspect of the nail plate. Ultrasonography showed a well-circumscribed hypoechoic area under the proximal aspect of the nail plate and the nail matrix. Color Doppler ultrasonography showed subtle flow signals within the hypoechoic area. Magnetic resonance imaging showed a well-circumscribed mass in the same place that the ultrasonography indicated. It was isointense to the dermis of the nail bed on the T1-weighted image and hyperintense on the T2-weighted image. Radiography showed subtle dorsal bone erosion in the distal phalanx. Surgery was performed. Histologically, the diagnosis of a subungual glomus tumor was made. We diagnosed the exact location and size of the subungual glomus tumor by preoperative imaging and completely removed it easily and safely. Imaging is very useful for diagnosing tumors of the nail unit.

The use of ultrasonography in preoperative localization of digital glomus tumors

Small glomus tumors of the digits of the hand are difficult to excise and may be associated with relatively high rates of recurrence. This study was designed to prospectively evaluate the utility of preoperative ultrasound localization of such tumors to facilitate removal and to reduce recurrence rates. During a 5-year period, 34 patients clinically diagnosed with glomus tumors involving their digits were examined with high-resolution ultrasonography (5 to 9 MHz). Color duplex sonography was further applied if flow characteristics were identified. The ultrasound-predicted and actual intraoperative sizes were correlated and analyzed using the paired t test. Patients were followed for 1 to 6 years, and results were documented. Sonography showed a hypoechoic nodule with prominent vascularity between the nail body and the dorsal cortex of the distal phalanx in all subungual tumors. Complete resection was possible in all 35 glomus tumors, with assistance by accurate preoperative ultrasound localization. There was no long-term recurrence among the 29 patients available for evaluation 1 to 6 years postoperatively. Ultrasonography has great advantages in defining the exact location and size of the glomus tumor preoperatively. Prior knowledge of the exact site and size of the glomus tumor facilitates excision and appears to reduce rates of recurrence. The collaboration between hand surgeons and radiologists is useful to successfully treat glomus tumors of the digit.

Recurrent glomus tumors of fingertips: MR imaging evaluation

PURPOSE

To determine the magnetic resonance (MR) imaging findings in recurrent glomus tumors of the fingertips.

MATERIALS AND METHODS

Twenty-four consecutive patients with recurrent pain after previous excision of a glomus tumor of the fingertip underwent MR imaging studies and surgery. T1-weighted spin-echo MR images were obtained in each patient before and after intravenous injection of contrast material; T2-weighted spin-echo and three-dimensional gradient-recalled echo images were also obtained. MR angiography was performed in four patients. Postsurgical histopathologic analysis revealed recurrent glomus tumors in 22 patients. Signal intensity, enhancement, and margins of the scar tissue and the recurrent tumors at MR were assessed.

RESULTS

The postsurgical scars were depicted in 21 (88%) of 24 patients with all sequences but were best demonstrated on gradient-recalled echo MR images. Seven patients had undergone multiple surgical procedures and had extensive scar tissue and, in one case, a neuroma. In all patients, MR imaging revealed a nodule compatible with the diagnosis of a recurrent glomus tumor. In 13 (54%) of 24 patients, the nodule had typical features of a glomus tumor. In eight (33%) of 24 patients, the tumors had low signal intensity or isointensity compared with the nail bed on T2-weighted images. In six (25%) of 24 patients, the tumors had faint enhancement after intravenous gadolinium chelate administration. The margins of the tumors were blurred by scar tissue in nine of 24 cases.

CONCLUSION

MR imaging can aid in the evaluation of recurrent glomus tumors.

Glomus tumors: report on eleven cases and a review of the literature

INTRODUCTION

Glomus tumor is a well known pathology in hand surgery; in addition to sites in the upper limbs, it can also affect the lower limbs and develop in other parts of the body.

MATERIALS AND METHODS

Seven females and four males with glomus tumors underwent surgery between 1990 and 1998 at our hospital. These cases were retrospectively studied, and immunohistochemical staining was carried out for vimentin, factor VIII and CD34.

RESULTS

At the time of diagnosis, the mean age of the patients was 49 years, with a mean follow-up of 18.5 months. Regarding tumor site, there were six digital, one wrist, two neck and two lower limb locations. In this series, familial incidence was observed in two cases, i.e., two sisters with tumor occurrence at the same digital site. Tumor size varied from 0.2 to 5 cm. In agreement with the findings in the literature, the present results showed only a low incidence of locations other than in the upper and lower limbs. Moreover, no multiple locations or degenerative malignancy were observed, both of which are known to be rare. In all cases, the histological aspect of these tumors was typically benign. Immunohistochemical studies of the tumor cells were positive for anti-vimentin antibody in all cases, negative for anti-factor VIII in all cases and irregularly positive for anti-CD34 antibody.

DISCUSSION

It was not possible to confirm the specificity of the anti-CD34 antibody for glomus tumor in this series. The hypothesis of the endothelial origin of glomus tumor can probably be dismissed in the absence of the expression of anti-factor VIII and anti-CD34 antibodies.

Diagnostic ultrasound of the hand and wrist

To assess the efficacy, role, and limitations of diagnostic ultrasound in the hand and wrist, the results of 98 examinations performed for a variety of surgical conditions were retrospectively analyzed. Ultrasound was shown to be reliable in evaluating radiolucent foreign body, tendon rupture versus tendon adhesion, tendinitis, peritendinitis, and ganglion cyst (specificity, 1; positive predictive value, 1). A correct suggestion of soft tissue mass histology was offered in six of eight operated cases. Tumor size and extent was accurately assessed in all but one case. The observed limitation of ultrasound was a small false negative rate in each category, which related to a variety of factors, including operator dependence, resolution threshold in the submillimeter range, image degradation due to postoperative edema, a narrow field of view, and one instance of indiscrete tumor margination. More work is needed to determine the role (if any) of ultrasound in the evaluation of peripheral nerve, triangular fibrocartilage, dorsal carpal ligament, and bone pathology.

[The contribution of MRI in the study of glomus tumors]

The glomus tumors of the finger tip are benign. Their diagnosis is clinic but their precise localization is quite difficult by classic imaging. MRI with gadolinium injection seemed a good method to check exactly this lesion and have been tested on 20 patients suspected suffering of glomus tumor. On 18 glomus tumors surgically and histologically confirmed MRI examination have been positive for 16. In two cases MRI and surgery were negative. A good correlation seems observed with surgery for the size (7 tumor of 2 mm) the localization and osseus extension. Addition of T2 and T1 before and after injection weighted acquisitions improved the results. Precise informations on topography and size seems improved the surgical approach.