An Approach to a Patient With Primary Hyperparathyroidism and a Suspected Ectopic Parathyroid Adenoma.

Primary hyperparathyroidism (PHPT) is characterized by hypercalcemia driven by excess parathyroid hormone (PTH) secretion. PHPT is a common endocrine condition with a prevalence of 1 to 7 cases per 1000 adults. PHPT typically presents in the fifth or sixth decade and shows significant female preponderance. Solitary hyperfunctioning parathyroid adenomas account for 85% to 90% of PHPT cases. The remaining 10% to 15% include cases of multiglandular disease (multiple adenomas or hyperplasia) and, rarely, parathyroid carcinoma (1%). Ectopic parathyroid adenomas may arise due to abnormal embryological migration of the parathyroid glands and can be difficult to localize preoperatively, making surgical cure challenging on the first attempt. The potential existence of multiglandular disease should be considered in all patients in whom preoperative localization fails to identify a target adenoma or following unsuccessful parathyroidectomy. Risk factors for multiglandular disease include underlying genetic syndromes (eg, MEN1/2A), lithium therapy, or previous radiotherapy. In addition to multifocal disease, the possibility of an ectopic parathyroid gland should also be considered in patients requiring repeat parathyroid surgery. In this article, we use illustrative clinical vignettes to discuss the approach to a patient with primary hyperparathyroidism (PHPT) and a suspected ectopic parathyroid adenoma.

Multiparametric Prostate Magnetic Resonance Imaging and Cognitively Targeted Transperineal Biopsy in Patients With Previous Abdominoperineal Resection and Suspicion of Prostate Cancer.

OBJECTIVE: To report our experience with a combination of prostate magnetic resonance imaging (MRI) and transperineal ultrasound biopsy for evaluating the prostate in patients with elevated prostate-specific antigen (PSA) who have previously undergone abdominoperineal resection (APR). PATIENTS AND METHODS: We reviewed the records of 11 patients with a history of APR and clinical suspicion of prostate cancer due to elevated PSA levels over a 5-year period. All patients underwent multiparametric MRI at our institution prior to biopsy. MR diagnoses were validated either by transperineal ultrasound biopsy (Likert 3-5) guided by visual registration or clinical follow-up >6 months (Likert 1-2). RESULTS: All 7 cases with highly suspicious lesions (Likert 4-5) on MRI demonstrated cancer-1 case of Gleason 3 + 3 and 6 cases of Gleason ≥3 + 4 disease. Two cases with Likert 3 MR lesions revealed benign tissue upon biopsy. Two patients with no suspicious lesions on MRI were followed-up clinically, with PSA levels remaining stable over a mean period of 17.5 months (range 7-28 months). CONCLUSION: The use of prebiopsy multiparametric prostate MRI and subsequent cognitively targeted transperineal biopsy guided by visual registration can aid in the diagnostic pathway of patients with APR and a suspicion of prostate cancer.

Intraoperative ultrasound to facilitate removal of a submucosal foreign body.

A 61-year-old man with a history of fish bone ingestion and poorly localized symptoms was seen. His clinical examination was unremarkable, but CT demonstrated a foreign body deeply embedded within his tongue. Intraoperative ultrasound (US) guidance facilitated identification of a bone, allowing a needle to be placed as a guide to dissection. Repeat US scanning through the incision permitted precisely targeted surgery. CT and US are the most effective imaging techniques for localizing fish bones. Intraoperative US can be used to accurately locate a submucosal fish bone in mobile tissue such as the tongue, and focused, image-guided dissection can reduce surgical tissue trauma.

A comprehensive study of clinical, biochemical, radiological, vascular, cardiac, and sleep parameters in an unselected cohort of patients with acromegaly undergoing presurgical somatostatin receptor ligand therapy.

CONTEXT: Attainment of safe GH and IGF-1 levels is a central goal of acromegaly management. OBJECTIVE: The aim of this study was to determine the extent to which reductions in GH and IGF-1 concentrations correlate with amelioration of radiological, metabolic, vascular, cardiac, and respiratory sequelae in a single unselected patient cohort. STUDY DESIGN: This was a prospective, within-subject comparison in 30 patients with newly diagnosed acromegaly (15 women and 15 men: mean age, 54.3 years; range, 23-78 years) before and after 24 weeks of lanreotide Autogel (ATG) therapy. RESULTS: Reductions in GH and IGF-1 concentrations and tumor volume were observed in all but 2 patients (median changes [Δ]: GH, -6.88 µg/L [interquartile range -16.78 to -3.32, P = .000001]; IGF-1, -1.95 × upper limit of normal [-3.06 to -1.12, P = .000002]; and pituitary tumor volume, -256 mm(3) [-558 to -72.5, P = .0002]). However, apnea/hypopnea index scores showed highly variable responses (P = .11), which were independent of ΔGH or ΔIGF-1, but moderately correlated with Δweight (R(2) = 0.42, P = .0001). Although systolic (P = .33) and diastolic (P = .76) blood pressure were unchanged, improvements in arterial stiffness (aortic pulse wave velocity, -0.4 m/s [-1.2 to +0.2, P = .046]) and endothelial function (flow mediated dilatation, +1.73% [-0.32 to +6.19, P = .0013]) were observed. Left ventricular mass index regressed in men (-11.8 g/cm(2) [-26.6 to -1.75], P = .019) but not in women (P = .98). Vascular and cardiac changes were independent of ΔGH or ΔIGF-1 and also showed considerable interindividual variation. Metabolic parameters were largely unchanged. CONCLUSIONS: Presurgical ATG therapy lowers GH and IGF-1 concentrations, induces tumor shrinkage, and ameliorates/reverses cardiac, vascular, and sleep complications in many patients with acromegaly. However, responses vary considerably between individuals, and attainment of biochemical control cannot be assumed to equate to universal complication control.

Utility of an intraoperative ultrasound in lateral approach mini-parathyroidectomy with discordant pre-operative imaging.

Objectives of this study were to assess the utility of intra-operative ultrasound to resolve discordant pre-operative imaging prior to a lateral approach mini-parathyroidectomy, by studying prospective case series in a head and neck endocrine unit. Patients with primary hyperparathyroidism due to a single adenoma with discordant pre-operative ultrasound and sestamibi were enrolled. They underwent a further intra-operative ultrasound by a head and neck radiologist with a view to proceed with a mini-parathyroidectomy. The main outcome measure was utility of intra-operative ultrasound compared to operative findings and pre-operative imaging. Secondary measures were complications of mini-parathyroidectomy, operative and ambulatory discharge time. Twenty-two patients underwent surgery with intra-operative ultrasound in the surgical position. The intra-operative ultrasound findings correlated with the operative findings in all cases (100 %). There were 16 inferior adenomas and 6 superior adenomas. Six inferior adenomas were in a retrosternal position, eight were obscured by benign thyroid lesions and a further two reported pre-operatively as superior. Three out of six superior adenomas were reported as inferior pre-operatively as the inferior thyroid artery was inadequately visualised, two were retro-carotid and one was retro-oesophageal. All patients were discharged within 23 h of surgery. There were no unsuccessful focused explorations. Histological analysis confirmed the adenomas. No morbidity (vocal cord palsy, haematoma, hungry bones) was noted. The results indicated that intra-operative ultrasound by a dedicated radiologist is a valuable tool in resolving discordance of pre-operative imaging. Appropriate patient positioning with neck extension and muscle relaxation allows placement of the probe in the obscure retro-carotid and retro-oesophageal locations and unmasks apparent "mediastinal" parathyroids facilitating focused dissection.

Increased prevalence of gallbladder polyps in acromegaly.

INTRODUCTION: Several studies have suggested an increased prevalence of benign and malignant tumors in acromegaly, particularly colonic neoplasms. The gallbladder's epithelial similarity to the colon raises the possibility that gallbladder polyps (GBP) may occur more frequently in acromegaly. PATIENTS AND METHODS: Thirty-one patients with newly diagnosed acromegaly (14 females, 17 males; mean age 54.7 yr, range 27-76 yr) were referred to our center between 2004 and 2008. All had pituitary adenomas and were treated with somatostatin analogs prior to transsphenoidal surgery. Biliary ultrasonography was performed at the time of referral. In a retrospective case-cohort study, we compared the prevalence of GBP in these scans with those of 13,234 consecutive patients (age range 20-80 yr) presenting at the hospital for abdominal/biliary ultrasound during the same time interval. Associations between GH and IGF-I levels and GBP in acromegaly were also examined. RESULTS: There was a higher prevalence of GBP in patients with acromegaly compared with controls (29.03 vs 4.62%, P = 0.000008); relative risk was 6.29 (95% confidence interval 3.61-10.96). Eight of nine patients with acromegaly and GBP were older than 50 yr of age. GH levels were higher in those with GBP (median 30.8 µg/liter, interquartile range 10.9-39.1) than those without (8.2 µg/liter, interquartile range 6.0-16.0), but IGF-I levels were comparable. CONCLUSIONS: This is the first study to demonstrate an increased prevalence of GBP in patients with newly diagnosed acromegaly. Further studies are required to determine whether these patients are at increased risk of developing gallbladder carcinoma and to define the role, if any, of biliary ultrasound surveillance.

Image-guided biopsy in patients with suspected ovarian carcinoma: a safe and effective technique?

In patients with suspected advanced ovarian carcinoma, a precise histological diagnosis is required before commencing neo-adjuvant chemotherapy. This study aims to determine the diagnostic accuracy and complication rate of percutaneous biopsies performed under ultrasound or computed tomography guidance. Between 2002 to 2007, 60 consecutive image-guided percutaneous biopsies were performed in patients with suspected ovarian cancer. The following variables were recorded: tissue biopsied, imaging technique, experience of operator, biopsy needle gauge, number of passes, complications, and final histology. Forty-seven patients had omental biopsies, 12 pelvic mass biopsies, and 1 para-aortic lymph node biopsy. Thirty-five biopsies were performed under ultrasound, 25 under computed tomography guidance. Biopsy needle gauges ranged from 14-20 swg with two to five passes for each patient. There were no complications. Histology was obtained in 52 (87%) patients. Percutaneous image-guided biopsy of peritoneal disease or pelvic mass is safe with high diagnostic accuracy. The large-gauge biopsy needle is as safe as the small gauge needle, but has the added value of obtaining tissue samples for immunohistochemistry and genomic studies.

Ultrasound-guided core-needle biopsy of the testis for focal indeterminate intratesticular lesions.

The aim of this study was to evaluate ultrasound (US)-guided core-needle testicular biopsy. Twelve biopsies were performed in eleven patients, under US guidance using disposable 16- or 18-gauge needles, between April 2003 and October 2006. Details were entered on a database and records reviewed 9 months to 3 years after biopsy. Final diagnoses were based on histology of the biopsy, open surgical resection where performed, and interval follow-up. Biopsies were well tolerated and no complications were encountered apart from a single minor testicular haemorrhage. Benign histology was demonstrated on the core-needle samples of six patients and US follow-up was compatible with these diagnoses. Of five patients whose core-needle biopsies yielded malignancy, two patients had primary testicular tumours; both have been treated successfully with orchiectomy and chemotherapy. Three patients with haematological malignancies had successful chemotherapy without orchiectomy; one of these three underwent post-chemotherapy biopsy demonstrating resolution. There are four main clinical scenarios when core-needle testicular biopsy is performed in our institution: (1) lesions with equivocal malignant US features, (2) discrepancy between radiological and clinical findings, (3) suspected malignant process where orchiectomy is unnecessary, e.g. lymphoma, (4) atrophic testes, where it is frequently difficult to differentiate malignancy from the heterogeneous echo pattern.

Rapid registration for wide field of view freehand three-dimensional ultrasound.

A freehand scanning protocol is the only way to acquire arbitrary large volumes of three-dimensional ultrasound (US) data. For some applications, multiple freehand sweeps are required to cover the area of interest. Aligning these multiple sweeps is difficult, typically requiring nonrigid image-based registration as well as the readings from the spatial locator attached to the US probe. Conventionally, nonrigid warps are achieved through general elastic spline deformations, which are expensive to compute and difficult to constrain. This paper presents an alternative registration technique, where the warp's degrees of freedom are carefully linked to the mechanics of the freehand scanning process. The technique is assessed through an extensive series of in vivo experiments, which reveal a registration precision of a few pixels with comparatively little computational load.

High-definition freehand 3-D ultrasound.

This paper describes a high-definition freehand 3-D ultrasound (US) system, with accuracy surpassing that of previously documented systems. 3-D point location accuracy within a US data set can be achieved to within 0.5 mm. Such accuracy is possible through a series of novel system-design and calibration techniques. The accuracy is quantified using a purpose-built tissue-mimicking phantom, designed to create realistic clinical conditions without compromising the accuracy of the measurement procedure. The paper includes a thorough discussion of the various ways of measuring system accuracy and their relative merits; and compares, in this context, all recently documented freehand 3-D US systems.

Sensorless freehand 3-D ultrasound using regression of the echo intensity.

In freehand 3-D ultrasound (US), a position sensor is attached to the probe of a 2-D US machine. The resulting 3-D data permit flexible visualisation and more accurate volume measurement than can be achieved using 2-D B-scans alone; however, the use of the position sensor can be inconvenient for the clinician. The objective is, thus, to replace the sensor with a technique for estimating the probe trajectory based on the B-scan images, themselves. One such technique exists, based on decorrelation algorithms. This paper presents an alternative approach based on linear regression of the echo-envelope intensity signal. A probabilistic analysis of the speckle characteristics of the US signal leads to a linear model, on which the regression algorithm is based. The gradient parameter of this model is shown to be directly related to probe motion. The viability of the new approach is demonstrated through simulations and in vitro and in vivo experiments.

US-guided core-needle biopsy of the thyroid gland.

PURPOSE: To evaluate safety, yield, and accuracy of ultrasonography (US)-guided core-needle biopsy of the thyroid gland. MATERIALS AND METHODS: Findings at 209 consecutive core-needle biopsies of lesions of the thyroid gland in 198 patients (median age, 48 years; age range, 14-80 years) were retrospectively reviewed. In 138 (66%), findings at previous fine-needle aspiration cytologic (FNAC) analysis were nondiagnostic on one to five occasions. Biopsy was performed as an outpatient procedure with direct US guidance by using nonadvancing 16-18-gauge core needles. Hospital records were reviewed 6 months to 5 years following biopsy to determine final diagnosis, delayed complications, and influence of biopsy findings on subsequent patient treatment. Final diagnoses were determined on the basis of findings at excisional histologic analysis, clinical course, or other laboratory values. The sensitivity, specificity, and accuracy of US-guided core-needle biopsy were calculated. RESULTS: One hundred ninety-nine (95%) specimens were adequate for histologic diagnosis. The sensitivity, specificity, and accuracy of core biopsy in differentiating neoplastic (malignant and benign) from nonneoplastic lesions of the thyroid gland were 96% (74 of 77), 89% (109 of 122), and 92% (183 of 199), respectively. The sensitivity, specificity, and accuracy of core-needle biopsy in the detection of malignant neoplasms were 61% (11 of 18), 100% (181 of 181), and 96% (192 of 199), respectively. After US-guided core-needle biopsy, 115 (58%) of 198 patients were treated conservatively, and no evidence of missed tumor manifested during the follow-up period. In the 83 patients who underwent surgical resection, biopsy was performed for therapeutic reasons in 76 (92%) and for diagnostic reasons in seven (8%). There were three cases of small postbiopsy hematomas and one of minor hemoptysis, but none required hospital admission. There were no major complications. CONCLUSION: US-guided core-needle biopsy of the thyroid gland is a safe outpatient procedure with a high diagnostic yield and accuracy, and frequently it obviates surgery in patients in whom findings at FNAC analysis are recurrently nondiagnostic.

Freehand 3D ultrasound without voxels: volume measurement and visualisation using the Stradx system.

This paper describes recent developments in the Stradx freehand 3D ultrasound system. Unlike other systems, Stradx works directly from the raw B-scans and their relative positions, without first resampling this unstructured data onto a regular voxel array. The paper discusses the many advantages of this unique approach, and presents new developments in the visualisation and quantitative analysis of freehand 3D ultrasound data, including novel volume rendering schemes and a robust method to compensate for the effects of varying probe pressure.

Speckle detection for 3D ultrasound.

Positioning accuracy of 3D ultrasound slice planes can be enhanced by speckle decorrelation of the B-scans. A suitable method requires accurate identification of zones of non-specular reflection in the image, a feature of parenchymal tissue. This has traditionally been achieved with statistics such as signal-to-noise ratios and measures of autocorrelation curves. Co-occurrence matrices and structural approaches have also been applied to ultrasound images. In this paper we assess the performance of these methods when only B-scan display data is available. We also report improved results with in vivo images using a proposed structural algorithm that detects speckle kernels. All detection algorithms yielded detection error rates between 28% and 38%, suggesting that user intervention may be required for clinically useful performance.

Analysis of speckle in ultrasound images using fractional order statistics and the homodyned k-distribution.

It is necessary to identify speckled regions in ultrasound images to control adaptive speckle suppression algorithms, for tissue characterisation, and to estimate the elevational separation of B-scans by speckle decorrelation. Previous authors have proposed classification techniques based on second order powers of the homodyned k-distribution, or lower order powers of the more limited k-distribution. In this paper we explore the speckle discrimination properties of statistics based on arbitrary powers of the ultrasound echo envelope signal using a combination of simulations and theoretical results from the homodyned k-distribution. We conclude that statistics based on powers less than one are surprisingly less effective than some higher powers. A simple discriminant function for speckle is evaluated quantitatively in simulation and qualitatively on sample B-scan images.

Head and neck lymphadenopathy: evaluation with US-guided cutting-needle biopsy.

PURPOSE: To evaluate ultrasonography (US)-guided core biopsy in the assessment of 247 patients with cervicofacial lymphadenopathy. MATERIALS AND METHODS: Two hundred sixty US-guided core biopsies were performed in 247 patients with cervicofacial lymphadenopathy. The age of the patients ranged from 1 to 91 years (mean, 50 years). Seventy-four (30%) had a history of malignancy. Biopsies were performed as outpatient procedures with direct US guidance and non-advancing 16-18-gauge core needles. Hospital records were reviewed 6 months to 5 years after biopsy. Final diagnoses were rendered based on results of histologic examination of excised specimens, clinical course, or results of other laboratory studies. RESULTS: Two hundred thirty-eight (92%) core biopsies yielded adequate material. In 28 (11%) patients, the histologic diagnosis was considered highly probable. In the 210 patients in whom adequate material was obtained and an unequivocal histologic diagnosis was given, the sensitivity, specificity, and accuracy of US-guided core needle biopsy in differentiating benign from malignant lymphadenopathy were 98.1%, 100%, and 98.7%, respectively. Seventy biopsies were performed in 66 patients with lymphoma. Sensitivity, specificity, and accuracy in differentiating lymphoma from reactive lymphadenopathy were 98.5%, 100%, and 98.7%, respectively. In 53 patients (80%) with lymphoma as a final diagnosis, histologic subclassification was sufficient to guide treatment without the need for surgical biopsy. There were no major complications and only three minor post-biopsy hematomas. CONCLUSION: US-guided core biopsy in patients with head and neck lymphadenopathy is a safe outpatient procedure that has a high diagnostic yield and accuracy and frequently obviates surgery.

Ultrasound of the male anterior urethra.

Ascending and descending techniques are used to demonstrate the male anterior urethra. The authors developed an ultrasound approach with the patient compressing his own urethra manually during voiding to achieve distension of the urethra with urine. The subsequent sonourethrography is more accurate than conventional fluoroscopic contrast studies in defining urethral filling defects and is as accurate for the demonstration of strictures. The technique has replaced contrast urethrography at the authors' institutions for the routine evaluation of the anterior urethra.