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Biomedical subjects

D N Smith

Publications and source records attributed to D N Smith.

At least 19 recordsLinked to original sources
PubMed2001

Breast ultrasound.

Ultrasound is second in importance only to mammography in the evaluation of breast abnormalities. The ability of US to diagnose benign simple cysts accurately has spared innumerable women from needless biopsies and aspirations. When a suspicious solid abnormality is detected by ultrasound, it readily provides convenient, inexpensive, accurate imaging guidance for interventional procedures. Future studies of US as a screening tool must weigh potential benefits against the potential risks because of increased biopsies performed for false-positive results.

Breast↗
PubMed2001

Case report: galactography-guided wire localization of an intraductal papilloma.

Galactography is used to evaluate spontaneous unilateral nipple discharge by catheterization of the duct orifice and instillation of radiopaque contrast material. The most common cause of a bloody discharge is an intraductal papilloma which appears as a smooth lobulated intraluminal filling defect or a solitary obstructed duct on galactography. Carcinomas may be the cause of up to 13% [1] of abnormal nipple discharge and cannot be reliably distinguished from papillomas at galactography. Thus any intraductal filling defect or irregularity in symptomatic patients should be surgically evaluated to obtain a tissue diagnosis. Unfortunately, the histologic examination of the biopsy specimen does not always identify the lesion seen at galactography [2]. A potentially more reliable method of locating lesions identified on galactography is described. Chow, J. S. (2001). Clinical Radiology56, 72-73.

Adult↗
PubMed2001

MR imaging-guided focused ultrasound surgery of fibroadenomas in the breast: a feasibility study.

PURPOSE: To test the feasibility of noninvasive magnetic resonance (MR) imaging-guided focused ultrasound surgery (FUS) of benign fibroadenomas in the breast. MATERIALS AND METHODS: Eleven fibroadenomas in nine patients under local anesthesia were treated with MR imaging-guided FUS. Based on a T2-weighted definition of target volumes, sequential sonications were delivered to treat the entire target. Temperature-sensitive phase-difference-based MR imaging was performed during each sonication to monitor focus localization and tissue temperature changes. After the procedure, T2-weighted and contrast material-enhanced T1-weighted MR imaging were performed to evaluate immediate and long-term effects. RESULTS: Thermal imaging sequences were improved over the treatment period, with 82% (279 of 342) of the hot spots visible in the last seven treatments. The MR imager was used to measure temperature elevation (12.8 degrees -49.9 degrees C) from these treatments. Eight of the 11 lesions treated demonstrated complete or partial lack of contrast material uptake on posttherapy T1-weighted images. Three lesions showed no marked decrease of contrast material uptake. This lack of effective treatment was most likely due to a lower acoustic power and/or patient movement that caused misregistration. No adverse effects were detected, except for one case of transient edema in the pectoralis muscle 2 days after therapy. CONCLUSION: MR imaging-guided FUS can be performed to noninvasively coagulate benign breast fibroadenomas.

Adult↗
PubMed2001

The utility of ultrasonographically guided large-core needle biopsy: results from 500 consecutive breast biopsies.

Five hundred ultrasonographically guided large-core needle breast biopsies of solid masses were performed in 446 women. Histopathologic results were correlated with imaging findings. Ultrasonographically guided large-core needle biopsy resulted in diagnosis of malignancy (n = 124) or severe atypical ductal hyperplasia (n = 4) in 128 lesions (26%). In the remaining 372 lesions (74%), ultrasonographically guided large-core needle biopsy yielded benign pathologic results. Follow-up of more than 1 year (n = 225), results of surgical excision (n = 50), or both were obtainable in 275 (74%) of the benign lesions. No malignancies were discovered at surgical excision or during follow-up of this group of benign lesions. There were no complications related to large-core needle biopsy that required additional treatment. Ultrasonographically guided large-core needle biopsy is a safe and accurate method for evaluating breast lesions that require tissue sampling.

Adolescent↗
PubMed2000

Atypical ductal hyperplasia and ductal carcinoma in situ as revealed by large-core needle breast biopsy: results of surgical excision.

OBJECTIVE: This investigation compares the frequency of histologic underestimation of breast carcinoma that occurs when a large-core needle biopsy reveals atypical ductal hyperplasia or ductal carcinoma in situ with the automated 14-gauge needle, the 14-gauge directional vacuum-assisted biopsy device, and the 11-gauge directional vacuum-assisted biopsy device. SUBJECTS AND METHODS: Evaluation of 428 large-core needle biopsies yielding atypical ductal hyperplasia (139 lesions) or ductal carcinoma in situ (289 lesions) was performed. The results of subsequent surgical excision were retrospectively compared with the needle biopsy results. RESULTS: For lesions initially diagnosed as ductal carcinoma in situ, underestimation of invasive ductal carcinoma was significantly less frequent using the 11-gauge directional vacuum-assisted biopsy device when compared with the automated 14-gauge needle (10% versus 21%, p < 0.05) but was not significantly less frequent when compared with the 14-gauge directional vacuum-assisted device (10% versus 17%, p > 0.1). For lesions diagnosed initially as atypical ductal hyperplasia, underestimation of ductal carcinoma in situ and invasive ductal carcinoma was significantly less frequent using the 11-gauge directional vacuum-assisted biopsy device compared with the 14-gauge directional vacuum-assisted device (19% versus 39%, p = 0. 025) and with the automated 14-gauge needle (19% versus 44%, p = 0. 01). CONCLUSION: The frequency of histologic underestimation of breast carcinoma in lesions initially diagnosed as atypical ductal hyperplasia or ductal carcinoma in situ using large-core needle biopsy is substantially lower with the 11-gauge directional vacuum-assisted device than with the automated 14-gauge needle and with the 14-gauge directional vacuum-assisted device.

Adult↗
PubMed1999

Large-core needle biopsy of nonpalpable breast lesions.

CONTEXT: An increasing number of nonpalpable abnormalities requiring breast biopsy are being identified due to the widespread use of screening mammography. Large-core needle biopsy (LCNB) has become an alternative to surgical excision. OBJECTIVE: To determine whether LCNB is a safe and accurate technique to evaluate nonpalpable abnormalities found on breast imaging studies. DESIGN AND SETTING: Case series at an institutional referral center from August 1, 1991, to December 31, 1997. PATIENTS: A total of 1643 women with 1 or more suspicious breast abnormalities received LCNBs (n = 1836 lesions). INTERVENTION: The LCNB of the breast uses a 14- or 11-gauge needle with stereotactic localization or ultrasound guidance. MAIN OUTCOME MEASURE: Utility and potential limitations of LCNB compared with the criterion standard, surgical excision after wire localization. RESULTS: Of the 1836 breast lesions sampled, 444 (24%) were found to be malignant. A total of 412 (22%) were found to be malignant on the initial LCNB and 202 repeat biopsies yielded 32 additional malignancies. Complications were infrequent: 1 patient experienced a superficial infection and 1 developed a pneumothorax after LCNB. CONCLUSION: Image-guided LCNB is a reliable diagnostic alternative to surgical excision of suspicious nonpalpable breast abnormalities.

Adult↗
PubMed1999

Image-guided core breast biopsy of ductal carcinoma in situ presenting as a non-calcified abnormality.

OBJECTIVE: Ductal carcinoma in situ (DCIS) typically presents as calcifications which are detected mammographically. Our aim was to evaluate the less common presentations of ductal carcinoma in situ diagnosed by image-guided core biopsy and correlate with histopathologic diagnoses. METHODS AND MATERIAL: Imaging and histopathologic findings were retrospectively reviewed in 11 patients with ductal carcinoma in situ diagnosed at core biopsy that presented as noncalcified radiographic abnormalities. RESULTS: Mammography showed non-calcified, circumscribed nodules, ill-defined nodules and architectural distortion. In two patients, no mammographic abnormality was detected. Sonography showed circumscribed, round or oval, solid masses; irregular, heterogeneous masses; and a tubular structure. Histopathologic diagnoses included multiple architectural subtypes and ranged from low to high nuclear grade. CONCLUSION: Although image-guided core biopsy diagnosis of ductal carcinoma is typically made when sampling calcifications, DCIS can be diagnosed following biopsy of non-calcified masses or distortion. There is no correlation between histopathologic subtype and radiologic appearance.

Adult↗
PubMed1999

Fibrous nodules found at large-core needle biopsy of the breast: imaging features.

PURPOSE: To describe the imaging and histologic features of large-core needle biopsy (LCNB) specimens of fibrous nodules. MATERIALS AND METHODS: Of 853 breast masses in which LCNB was performed, 38 (4%) revealed histologic findings of fibrous nodules. Repeat biopsy was performed in 16 lesions (surgical excision, 13 lesions; repeat LCNB, three lesions). The mammographic and ultrasonographic findings in these 16 cases, the histologic LCNB findings, and the repeat biopsy findings were retrospectively reviewed. RESULTS: Repeat biopsy findings confirmed the diagnosis of fibrous nodules in 15 of the 16 masses. In one mass, repeat LCNB findings showed a fibroadenoma. The imaging features of the fibrous nodules varied. Five nodules (33%) manifested as masses with indistinct margins; six (40%), as circumscribed masses. In four cases (27%), imaging suggested malignancy. None were calcified masses. An additional 22 masses had circumscribed or indistinct borders and were diagnosed with LCNB as fibrous nodules. None of these masses had suspicious findings, and repeat biopsy was not performed. CONCLUSION: Fibrous nodules usually manifest as masses with circumscribed or indistinct margins but can have findings suggestive of malignancy. LCNB can reveal histologic findings consistent with this diagnosis. In all masses in which repeat biopsy was performed, the diagnosis of a fibrous nodule was confirmed or another benign stromal lesion was diagnosed.

Adult↗
PubMed1998

The psychocultural roots of genocide. Legitimacy and crisis in Rwanda.

In April 1994, the small east African nation of Rwanda became the site of one of the most violent episodes of the 20th century. Over the course of just 100 days, an embattled authoritarian state organized the slaughter of at least 850,000 Rwandans. Briefly, worldwide attention was riveted. But clichés about "age-old tribal hatreds" soon dominated discussion, conveying the impression that this was simply the latest episode in an unending cycle of violence. The truth, however, is quite different. The April genocide was in many ways unique. It was neither tribal nor age-old, and it is hardly fated to recur. Indeed, the author's premise is that if this genocide is grasped in all its psychocultural novelty and complexity, a point of Archimedean leverage can be found for interventions to avert tragedies in the future.

Anomie↗
PubMed1998

Large-needle core biopsy: nonmalignant breast abnormalities evaluated with surgical excision or repeat core biopsy.

PURPOSE: To classify lesions initially considered nonmalignant at large-needle core biopsy that were subsequently surgically excised or sampled at repeat biopsy. MATERIALS AND METHODS: From August 1, 1991, to December 31, 1996, 1,032 breast abnormalities (214 malignant and 818 nonmalignant lesions) were sampled at large-needle core biopsy. Of the nonmalignant lesions, 112 (14%) abnormalities were studied. Twenty-four abnormalities were subsequently excised because of discordant imaging and pathologic findings; 41 may have been missed at biopsy (25 were surgically excised, and 16 were sampled at repeat biopsy); 40 were surgically excised as recommended by the pathologist; and seven were excised for other indications. RESULTS: None of 24 abnormalities excised because of discordant findings was malignant. Among the 41 possibly missed lesions, infiltrating ductal carcinoma was found in one lesion that was removed surgically and in one sampled at repeat biopsy. Among the 40 lesions recommended for excision by the pathologist, 16 malignancies were found (ductal carcinoma in situ, 11; infiltrating ductal carcinoma, three; phyllodes tumor, two). None of the remaining seven lesions was malignant. CONCLUSION: Correlation of the technical quality of the biopsy, imaging features, and pathologic findings resulted in 96 surgical excisions and 16 repeat biopsies of lesions initially considered nonmalignant. Eighteen additional malignancies were identified.

Biopsy, Needle↗
PubMed1998

Collagen injection therapy for post-prostatectomy incontinence.

PURPOSE: Post-prostatectomy incontinence has an incidence of 5 to 12% and greatly affects quality of life. Since the approval of glutaraldehyde cross-linked collagen there is a renewed interest in injectable urethral bulking agents. We investigated the long-term efficacy and prognostic criteria for transurethral collagen injection therapy for men with post-prostatectomy incontinence. MATERIALS AND METHODS: From November 1993 to May 1995, 62 men with post-prostatectomy incontinence (54 after radical prostatectomy and 8 after transurethral resection of the prostate) were treated with collagen via a transurethral approach. Median followup was 29.0 months from the date of the last injection procedure. RESULTS: Social continence was defined as dry or minimal leakage requiring at most 1 pad daily with activity. Of 62 patients 38.7% achieved social continence and 8.1% became totally dry. The success rate was 35.2 for radical prostatectomy versus 62.5% for transurethral prostatic resection patients. Of the patients who achieved social continence with at least 1-year followup 23 (60.9%) remained so with no further treatment. At 2-year followup 21 patients (42.8%) maintained social continence. The success rate was 27.3% for those who wore a penile clamp or condom catheter before treatment (3 of 11 patients), and only 21.4% for those who underwent transurethral incision of a bladder neck contracture (3 of 14). A median of 4 injection procedures and 20.0 ml. collagen were required to achieve social continence. CONCLUSIONS: Transurethral collagen injection therapy is a reasonable treatment option for post-prostatectomy incontinence in select patients in whom more conservative therapy has failed. However, patients who have required a penile clamp, experienced continuous leakage or undergone transurethral incision of a bladder neck contracture are unlikely to respond well to this treatment.

Activities of Daily Living↗
PubMed1997

Large-core needle biopsy of nonpalpable breast cancers. The impact on subsequent surgical excisions.

OBJECTIVE: To compare the subsequent surgical therapy for women with nonpalpable breast cancers diagnosed by large-core needle biopsy (LCNB) vs those diagnosed by surgical excision after wire localization. DESIGN: Retrospective review of cases and results. SETTING: Secondary referred care. PATIENTS: A total of 677 women diagnosed as having breast cancer by LCNB (n = 67) or by surgical excision after wire localization (n = 610). RESULTS: Women in the LCNB group underwent an average of 1.25 surgical procedures and women whose breast cancers were diagnosed by surgical excision after preoperative wire localization underwent an average of 2.01 surgical procedures (P < .001). CONCLUSIONS: Large-core needle biopsy decreases the number of surgical procedures in women diagnosed as having nonpalpable breast cancers. Increased implementation of this technique will substantially decrease the costs of surgical therapy in these patients.

Biopsy, Needle↗
PubMed1997

Impalpable breast cysts: utility of cytologic examination of fluid obtained with radiologically guided aspiration.

PURPOSE: To evaluate the utility of cytologic analysis of fluid obtained from impalpable breast cysts by means of radiologically guided aspiration. MATERIALS AND METHODS: The authors retrospectively reviewed the reports of cytologic examinations of fluid obtained with sonographically or mammographically guided aspiration of 660 impalpable breast cysts in 583 women during 3 1/2 years. RESULTS: No malignant cells (541 cysts) or insufficient cellular material (86 cysts) was seen with cytologic examination of 95% of the aspirates. Atypical cells were seen with cytologic examination of fluid from 33 (5%) lesions. None of these 33 lesions were found to represent malignancy at the time of surgical excision (n = 9) or during clinical follow-up (n = 24). CONCLUSION: Routine cytologic examination is unnecessary if the fluid obtained with radiologically guided aspiration from impalpable breast cysts is not bloody.

Adult↗
PubMed1997

Epidermal inclusion cysts of the breast: three lesions with calcifications.

PURPOSE: To determine whether there are any mammographic and ultrasonographic (US) features of epidermal inclusion cysts of the breast, including heterogeneous microcalcifications, that may be used to preclude unnecessary biopsy. MATERIALS AND METHODS: Clinical history and imaging findings in 15 patients who had undergone surgical excision of an epidermal inclusion cyst were reviewed. RESULTS: In 11 patients, imaging findings of an epidermal inclusion cyst were noted, including 10 patients with mammographic findings, one with US findings only, and seven with mammographic and US findings. The most common mammographic finding (in nine of 10 patients) was an isodense to high-density mass with a circumscribed margin; three circumscribed masses had multiple associated heterogeneous microcalcifications. In the seven patients with corresponding US findings, a circumscribed hypoechoic mass with through transmission was depicted. An additional US feature in six patients was extension of the mass into the dermis. CONCLUSION: Biopsy may be deemed unnecessary if the characteristic US and physical examination findings are present, even in the case of a cyst with heterogeneous microcalcifications.

Adult↗
PubMed1997

Stereotactic breast biopsy of clustered microcalcifications with a directional, vacuum-assisted device.

The success rate with the traditional 14-gauge, core-biopsy, multiple-pass technique was compared with that of a directional vacuum-assisted device in sampling calcification clusters in the breast. Of the 130 focal calcification clusters sampled with the multiple-pass technique, 12 clusters (9.2%) had no particles depicted on radiographs of the specimen. Specimens from all 106 (100%) clusters sampled with the directional, vacuum-assisted instrument contained calcifications at radiography. The directional, vacuum-assisted device improved the ability to percutaneously sample breast calcifications.

Biopsy, Needle↗
PubMed1997

Collagen injection therapy for female intrinsic sphincteric deficiency.

PURPOSE: Since glutaraldehyde cross-linked collagen was approved for use, studies have reported success or improved rates of 63 to 86%. Long-term efficacy with strictly defined outcome criteria has not been reported. We report our experience with collagen injection therapy for female patients with intrinsic sphincteric deficiency to establish efficacy, duration of response and clinical predictors of success. MATERIALS AND METHODS: A total of 96 women underwent collagen injection via a periurethral approach with local anesthesia. In all patients history, physical examination and video urodynamics documented intrinsic sphincteric deficiency without urethral hypermobility. Continence success was defined as dry or socially continent (minimal leakage requiring 1 or no pad daily even with strenuous activity). Median followup was 14.0 months. RESULTS: Of 94 patients 67.0% achieved continence, 38.3% became dry and 28.7% became socially continent. Of 35 patients who achieved continence with at least 1 year of followup 6 had regression. Therefore, 82.9% of those successfully treated remained so at 1 year and none had de novo detrusor instability. An average of 2.1 procedures and 11.9 ml. collagen were required to achieve continence. The 31 patients not achieving success underwent an average of 3.2 procedures with 16.1 ml. collagen. No major complications have occurred to date. CONCLUSIONS: Collagen injection achieves a reasonable rate of continence and good durability at 1 year of followup in female patients with intrinsic sphincteric deficiency and no urethral hypermobility.

Aged↗
PubMed1997

A virtual repository approach to clinical and utilization studies: application in mammography as alternative to a national database.

A national mammography database was proposed, based on a centralized architecture for collecting, monitoring, and auditing mammography data. We have developed an alternative architecture relying on Internet-based distributed queries to heterogeneous databases. This architecture creates a "virtual repository", or a federated database which is constructed dynamically, for each query and makes use of data available in legacy systems. It allows the construction of custom-tailored databases at individual sites that can serve the dual purposes of providing data (a) to researchers through a common mammography repository and (b) to clinicians and administrators at participating institutions. We implemented this architecture in a prototype system at the Brigham and Women's Hospital to show its feasibility. Common queries are translated dynamically into database-specific queries, and the results are aggregated for immediate display or download by the user. Data reside in two different databases and consist of structured mammography reports, coded per BIRADS Standardized Mammography Lexicon, as well as pathology results. We prospectively collected data on 213 patients, and showed that our system can perform distributed queries effectively. We also implemented graphical exploratory analysis tools to allow visualization of results. Our findings indicate that the architecture is not only feasible, but also flexible and scaleable, constituting a good alternative to a national mammography database.

Computer Communication Networks↗