William A. Erdman

Lymphatic Mapping and Sentinel Node Identification in Patients With Cervix Cancer Undergoing Radical Hysterectomy and Pelvic Lymphadenectomy

PURPOSE The purpose of this study was to determine the feasibility of sentinel node identification in patients with invasive cervix cancer undergoing radical hysterectomy and pelvic lymphadenectomy using preoperative and intraoperative lymphatic mapping. PATIENTS AND METHODS Thirty-nine patients at two institutions were enrolled onto this institutional review board-approved study. All underwent preoperative lymphoscintigraphy and intraoperative lymphatic mapping with blue dye and a handheld gamma probe. Radical hysterectomy was aborted in four patients because metastatic disease was discovered on frozen section analysis of the sentinel node. RESULTS Preoperative lymphoscintigraphy revealed at least one sentinel node in 33 patients (85%), including 21 (55%) with bilateral sentinel nodes. All 39 patients had at least one sentinel node identified intraoperatively. Eighty percent of sentinel nodes were in three pelvic locations: iliac, obturator, and parametrial (in descending order of frequency). The remaining sentinel nodes were in the common iliac and para-aortic nodal basins. A total of 132 nodes were identified clinically as sentinel nodes; 65 (49%) were both blue and hot, 35 (27%) were blue only, and 32 (24%) were hot only. Eight patients (21%) had metastatic disease. In five of these patients, sentinel nodes were the only positive lymph nodes. One patient had false-negative sentinel nodes. She had four microscopically positive parametrial nodes that were resected in continuity with the uterus. The sensitivity of the sentinel node was 87.5% and the negative predictive value was 97%. CONCLUSION Preoperative lymphoscintigraphy and intraoperative lymphatic mapping were highly successful at identifying sentinel nodes in patients undergoing radical hysterectomy.

Sentinel lymph node biopsy, an alternative to elective axillary dissection for breast cancer

BACKGROUND Axillary metastases remain an important prognostic indicator in breast cancer. Axillary lymphadenectomy (ALND) carries significant morbidity and is unnecessary in most patients with early breast cancer; thus, sentinel lymph node (SLN) biopsy has been advocated for axillary staging. We studied the SLN identification rate and its accuracy in predicting axillary metastases. METHODS One hundred nineteen women with breast carcinoma underwent SLN and ALND. Lymphoscintigraphy was performed using Technetium99 sulfur colloid supplemented by Isosulfan blue dye. Hematoxylin/eosin-stained lymph node sections were examined by light microscopy. RESULTS The SLN identification rate was 81%. One SLN was negative (1%) in a patient with axillary disease. SLN histology correctly predicted the absence of axillary disease in 98.6%. Sensitivity, specificity, and positive and negative predictive values were 96%, 100%, 100%, and 99%, respectively. CONCLUSIONS Sentinel lymph node biopsy accurately predicts total axillary status and is valuable in the surgical staging of breast cancer.

Meta-analysis: comparison of F-18 Fluorodeoxyglucose-positron emission tomography and bone scintigraphy in the detection of bone metastases in patients with breast cancer.

Purpose: To evaluate the diagnostic properties of FDG-PET and bone scintigraphy in the detection of osseous metastases in patients with breast cancer. Materials and Methods: Studies evaluating the diagnostic accuracy of FDG-PET and bone scintigraphy in the diagnosis of osseous metastasis were systematically searched for in the MEDLINE, CINAHL, and EBM Review databases from January 1995 to November 2006. Two reviewers independently abstracted data including research design, sample size, imaging technique and technical characteristics, reference standard, method of image interpretation, and totals of true positives, false positives, true negatives, and false negatives. Per-patient and per-lesion pooled sensitivity and specificity, and area under summary receiver operating characteristic curves were calculated using Meta-Test software. Results: The pooled patient-based sensitivity for FDG-PET was 81% (95% CI: 70%–89%), specificity was 93% (95% CI: 84%–97%), and the area under the curve (AUC) was 0.08. The pooled sensitivity of bone scan was 78% (95% CI: 67%–86%), specificity was 79% (95% CI: 40%–95%), and the AUC was 0.43. The pooled lesion-based sensitivity for FDG-PET was 69% (95% CI: 28%–93%), specificity was 98% (95% CI: 87%–100%), and the AUC was 0.09. The pooled sensitivity for bone scan was 88% (95% CI: 82%–92%), specificity was 87% (95% CI: 29%–99%), and the AUC was 0.81. Conclusions: It remains inconclusive whether FDG-PET or bone scintigraphy is superior in detecting osseous metastasis from breast cancer. However, FDG-PET does have a higher specificity and may better serve as a confirmatory test than bone scintigraphy and used to monitor response to therapy.

Noninvasive localization of parathyroid adenomas: A comparison of X-ray computerized tomography, ultrasound, scintigraphy and MRI

Thirty-two (32) patients with primary hyperparathyroidism (17 with prior localization surgery, 15 without) were studied by a combination of computed tomography (CT), ultrasound (US), nuclear medicine (NM), and magnetic resonance imaging (MRI) for parathyroid adenoma localization. The sensitivity and true-positive ratio of each imaging technique and various combinations of techniques were evaluated. Of the 28 proven parathyroid adenomas (27 by surgery, 1 by digital subtraction angiography), 24 were imaged by two techniques, 19 by three techniques, and 10 by all four imaging techniques. The sensitivities were NM (65%), CT (76%), US (77%), and MRI (81%). The differences between true-positive ratios of 82%, 64%, 71%, and 77%, respectively, were not statistically significant. If multiple techniques were considered as a single test (i.e., a positive localization requires two or more tests to be positive at the same location), then sensitivity for a two-study combination was 79% and true-positive ratio 86%. Three techniques showed a sensitivity of 63% and a true-positive ratio of 92%, four modalities 40% and 100%, respectively. There was no significant difference in the various combinations of techniques employed (e.g., CT and US, US and MR, NM and MR, etc.). Thus, there appears to be an advantage in performing multiple techniques (regardless of which combination is selected) until two tests are positive at the same location.

Indexing Severity of Diabetic Foot Infection With 99mTc-WBC SPECT/CT Hybrid Imaging

OBJECTIVE Management of diabetic foot infection (DFI) has been hampered by limited means of accurately classifying disease severity. New hybrid nuclear/computed tomography (CT) imaging techniques elucidate a combination of wound infection parameters not previously evaluated as outcome prognosticators. Our aim is to determine if a novel standardized hybrid image–based scoring system, Composite Severity Index (CSI), has prognostic value in DFI. RESEARCH DESIGN AND METHODS Masked retrospective 99mTc-white blood cell (WBC) single photon emission CT (SPECT)/CT image interpretation and independent chart review of 77 patients (101 feet) suspected of DFI-associated osteomyelitis at a large municipal hospital between January 2007 and July 2009. CSI scores were correlated with probability of favorable outcome (no subsequent amputation/readmission after therapeutic intervention) during median 342-day follow-up. RESULTS CSI ranged from 0–13. Receiver operating characteristic accuracy for predicting favorable outcome was 0.79 (optimal cutoff CSI, ≤2; odds ratio of therapeutic failure for CSI >2, 15.1 [95% CI 4.4–51.5]). CSI of 0 had a 92% chance of favorable outcome, which fell progressively to 25% as indices rose to ≥7. Image-based osteomyelitis versus no osteomyelitis assessment was less accurate than CSI at predicting outcome (P = 0.016). In patients with intermediate severity (CSI 3–6), treatment failure decreased from 68 to 36% when antibiotic duration was extended to ≥42 days (P = 0.026). CONCLUSIONS 99mTc-WBC SPECT/CT hybrid image–derived wound infection parameters incorporated into a standardized scoring system, CSI, has prognostic value in DFI.

Angiographic Ablation of Mediastinal Parathyroid Adenomas: Local Experience and Review of the Literature

PURPOSE To evaluate local experience with a modified technique for angiographic ablation of mediastinal parathyroid adenomas. PATIENTS AND METHODS Three patients with likely mediastinal parathyroid adenomas that had single feeding arteries underwent attempted arteriographic ablation with a slow continuous infusion of contrast medium. Patients were closely monitored for symptoms and calcium dynamics immediately postprocedure and then on a long-term outpatient basis. RESULTS All three patients were cured (follow-up 22 to 68 months) with no long-term complications. CONCLUSION Percutaneous angiographic ablation with contrast medium is a reasonable alternative for patients with hyperparathyroidism due to a mediastinal adenoma who can be treated in centers with well-trained interventional radiologists.

Magnetic resonance imaging of pulmonary embolism

Magnetic resonance imaging (MRI) has the unique ability to demonstrate pulmonary emboli, venous thrombosis, and normal pulmonary arteries in a single noninvasive study. Spin echo and gradient echo pulse sequences take advantage of the natural high contrast between flowing blood and intraluminal thrombus or embolus. Magnetic resonance angiographic (MRA) techniques offer three-dimensional display of the pulmonary vasculature. Each of these techniques may be viewed in cinematic fashion to depict hemodynamic changes associated with the cardiac cycle. Clinical studies have demonstrated sensitivity in the 75% to 100% range and specificities between 42% and 90% depending on technique. MRI technology is still rapidly advancing and clinical accuracy will no doubt improve as experience with new techniques develops. At present, MRI should play a complimentary role to conventional methods of diagnosing thromboembolic disease.

Morphologic Renal Changes Following Piezoelectric Lithotripsy or Spark-Gap Lithotripsy

Morphologic changes of the kidney following extracorporeal shock wave lithotripsy (ESWL†) have been demonstrated by magnetic resonance imaging (MRI) to be present in as many as 85% of patients treated with first-generation electrohydraulic lithotripters. In this study the renal morphologic changes produced by a second-generation piezoelectric machine (Wolf Piezolith 2300) were compared to those of an electrohydraulic lithotripter (Dornier HM3). The mean stone size was 11 mm, and the mean number of shock waves on the Wolf lithotripter was 3,900 at an average power intensity of 900 bar and on the Dornier device was 1,760 shock waves at 21 kV. All patients were studied with renal MRI scans 24 hours following lithotripsy. A subsequent MRI scan was performed at two weeks and then at one month if any changes were noted on the prior study.

67Ga uptake after cosmetic augmentation with silicone in HIV-infected patient with unexplained hypercalcemia: Utility of SPECT/CT

A 56-year-old HIV-infected man underwent Ga scintigraphy because of unexplained hypercalcemia, elevated calcitriol, and concern for chronic granulomatous disease, including tuberculosis. Although no abnormalities were identified to indicate sarcoidosis or tuberculosis, increased radiotracer accumulation in the face and gluteal region was observed. On questioning, the patient revealed a 3-year history of liquid silicone use for soft-tissue augmentation of the face and buttocks. After SPECT/CT imaging, the etiology of the patient’s hypercalcemia was attributable to siliconeinduced granulomatosis. We present this case to highlight the appearance of Ga uptake on SPECT/CT after cosmetic augmentation with liquid silicone in the face and buttocks and silicone-induced granulomatosis as a cause of unexplained elevated vitamin D and hypercalcemia.

Development Of A Digital Nuclear Medicine System

A Nuclear Medicine Department has implemented a central computer system which stores all gamma camera images on hard disc. Multiple terminals allow simultaneous acquisition, processing and archiving of these images from various narts of the hospital. Downtime has been negligible and a months work of patient studies is easily stored on line.