- Email: [email protected]
0668: Contrast Enhanced Ultrasound for Imaging of Adrenal Masses
Abstracts 0668 Contrast Enhanced Ultrasound for Imaging of Adrenal Masses Dagmar G Schreiber, Caritas-Krankrenhaus Bad Mergentheim, University Frankfurt, Germany Barbara Braden, Caritas-Krankrenhaus Bad Mergentheim, University Oxford, Germany Andre Ignee, Caritas-Krankrenhaus Bad Mergentheim, University Frankfurt, Germany Ana P Barreiros, Caritas-Krankrenhaus Bad Mergentheim, University Mainz, Germany Christoph F Dietrich, Caritas-Krankenhaus Bad Mergentheim, University Frankfurt, Germany Purpose: The number of incidentally discovered adrenal masses is growing due to the increased use of modern high resolution imaging techniques. However, the characterization and differentiation between benign and malignant adrenal lesions is challenging. This study aimed to evaluate contrast enhanced ultrasound for characterization of adrenal masses. Methods: We studied 58 patients with adrenal masses detected on computed tomography, magnetic resonance imaging or ultrasound. 7 patients had bilateral adrenal lesions. Contrast enhanced ultrasound was performed using high-resolution ultrasound (3.5 - 7 MHz) and intravenous injection of 2.4 ml SonoVue®. The contrast enhancement pattern of all adrenal lesions was documented. Results: The 18 malignant adrenal tumours were significantly larger at time of diagnosis compared to the 40 benign lesions (p⬍0.03). The majority of benign adrenal lesions (37/40) had an unspecific type of contrast enhancement (24/40) or a peripheral to central contrast filling (13/40) as described as iris phenomenon. Similar findings were observed in malignant adrenal tumours: Most malignant lesions also showed unspecific (6/18) or peripheral to central contrast filling (9/18). Peripheral to central contrast filling had 50 % sensitivity (26 %-74 %) and 68 % specificity (51 %-81 %) for indicating malignancy. Conclusions: Contrast enhanced ultrasound facilitates the visualisation of the vascularisation even in small adrenal masses, but it does not help to distinguish malignant and benign lesions. 0671 An Evidence Based Protocol for Ultrasound Screening in Monochorionic Diamniotic Twins Jon Hyett, Royal Prince Alfred Hospital, Australia Approximately 22 % of all twins are monochorionic, giving a prevalence of 1 in 320 births. Data from an unselected population show that 50% of these pregnancies will be complicated. Monochorionic twins have 6x risk of miscarriage (⬍24 weeks) and 2x risk of preterm birth, growth restriction or intrauterine death compared to dichorionic twins. Review of a cohort referred for a tertiary opinion found that the presumed pathology was incorrect in 50% of cases. A formal protocol describing appropriate surveillance for monochorionic twins may improve the identification of complications and allow earlier referral when intervention is more likely to succeed. Surveillance relies on early diagnosis, normal defined by assessment of the intertwin membrane at the time of the 12 week scan. At this gestation, large differences in the CRL and NT values of the two fetuses are associated with a higher risk of twin twin transfusion (TTS) and other complications. Lethality between 16 and 24 weeks gestation appears to be primarily associated with TTS, which can be treated effectively with laser ablation. The current staging system does not necessarily reflect disease progression and the inherent unpredictability of this condition makes scanning very two weeks worthwhile.
S93
A second peak for intrauterine death is seen in the late third trimester (⬎34 weeks) so continued surveillance beyond 24 weeks gestation is recommended, including assessment of growth velocity. Assessment of the umbilical artery waveform and of mid-cerebral artery blood velocity may be useful in identifying a group of fetuses with evidence of unstable anastamoses.
0674 Sonography of Wrist Lumps, Bumps, Nerves and Ligaments Bill Breidahl, Perth Radiological Clinic, Australia Objectives - to know the common soft tissue masses of the wrist and fingers and their US appearance - identify signs of and causes for nerve dysfunction at the level of the wrist - appreciate the normal and abnormal appearance of the scapholunate ligament Soft tissue masses Sonography can readily diagnose the majority of soft tissue masses around the wrist, of which approximately 25% respectively are - ganglia - non tumour tendon pathology - soft tissue neoplasms (usually benign) - other Ganglia usually appear on US as uni or multilocular anechoic masses, often with tortuous necks extending from their site of origin. Hypertrophic accessory muscles can present as soft tissue masses and the extensor digitorum brevis manus muscle may mimick a dorsal SL ganglion. Most soft tissue masses in the digits can be confidently diagnosed with sonography. Ganglia are commonest. The commonest solid mass in the digit is the entity of Giant Cell Tumor of Tendon Sheath. It has a lobulated or multi-lobulated contour, contains relatively uniform low level echoes and may demonstrate flow on colour Doppler. Glomus tumors typically occur in the region of the nail bed. They are hypoechoic. They usually (but not always) are hyperemic on colour Doppler. Nerve Disorders Carpal tunnel syndrome (CTS) is a clinical syndrome supported by EMG findings. Diagnostic US may be helpful in cases of carpal tunnel syndrome with unusual or atypical manifestations, particularly for the exclusion of a soft tissue mass or flexor tenosynovitis. A number of US findings have been found to be present in idiopathic carpal tunnel syndrome, both subjective (eg loss of deformability) and objective (cross sectional area ⬎ 0.09cm2). The main role of US is to exclude a secondary cause of CTS, although some authors suggest it is comparable to EMG and may be considered the initial investigation - this is controversial. Anatomic variations at the wrist are common and are often implicated as the causative factor in the development of carpal and ulnar tunnel syndromes. A high bifurcation of the median nerve, persistent median artery and anomalous muscles have all been associated with carpal tunnel syndrome. Guyons canal is a fibroosseus tunnel formed by the flexor retinaculum and pisiform through which the ulnar nerve passes. Causes of ulnar nerve pathology at this level include - Repetitive trauma eg cyclists Mass eg ganglion Fractured hook of hamate Ulnar artery thrombosis
S93
A second peak for intrauterine death is seen in the late third trimester (⬎34 weeks) so continued surveillance beyond 24 weeks gestation is recommended, including assessment of growth velocity. Assessment of the umbilical artery waveform and of mid-cerebral artery blood velocity may be useful in identifying a group of fetuses with evidence of unstable anastamoses.
0674 Sonography of Wrist Lumps, Bumps, Nerves and Ligaments Bill Breidahl, Perth Radiological Clinic, Australia Objectives - to know the common soft tissue masses of the wrist and fingers and their US appearance - identify signs of and causes for nerve dysfunction at the level of the wrist - appreciate the normal and abnormal appearance of the scapholunate ligament Soft tissue masses Sonography can readily diagnose the majority of soft tissue masses around the wrist, of which approximately 25% respectively are - ganglia - non tumour tendon pathology - soft tissue neoplasms (usually benign) - other Ganglia usually appear on US as uni or multilocular anechoic masses, often with tortuous necks extending from their site of origin. Hypertrophic accessory muscles can present as soft tissue masses and the extensor digitorum brevis manus muscle may mimick a dorsal SL ganglion. Most soft tissue masses in the digits can be confidently diagnosed with sonography. Ganglia are commonest. The commonest solid mass in the digit is the entity of Giant Cell Tumor of Tendon Sheath. It has a lobulated or multi-lobulated contour, contains relatively uniform low level echoes and may demonstrate flow on colour Doppler. Glomus tumors typically occur in the region of the nail bed. They are hypoechoic. They usually (but not always) are hyperemic on colour Doppler. Nerve Disorders Carpal tunnel syndrome (CTS) is a clinical syndrome supported by EMG findings. Diagnostic US may be helpful in cases of carpal tunnel syndrome with unusual or atypical manifestations, particularly for the exclusion of a soft tissue mass or flexor tenosynovitis. A number of US findings have been found to be present in idiopathic carpal tunnel syndrome, both subjective (eg loss of deformability) and objective (cross sectional area ⬎ 0.09cm2). The main role of US is to exclude a secondary cause of CTS, although some authors suggest it is comparable to EMG and may be considered the initial investigation - this is controversial. Anatomic variations at the wrist are common and are often implicated as the causative factor in the development of carpal and ulnar tunnel syndromes. A high bifurcation of the median nerve, persistent median artery and anomalous muscles have all been associated with carpal tunnel syndrome. Guyons canal is a fibroosseus tunnel formed by the flexor retinaculum and pisiform through which the ulnar nerve passes. Causes of ulnar nerve pathology at this level include - Repetitive trauma eg cyclists Mass eg ganglion Fractured hook of hamate Ulnar artery thrombosis