Tifha Horne

The Effect of sildenafil on gastric emptying in patients with end-stage renal failure and symptoms of Gastroparesis

Delayed gastric emptying is a common disorder among patients with end‐stage renal failure (ESRF). Pyloric relaxation, a major determinant of gastric emptying, is a nitric oxide (NO)–mediated process. NO‐induced smooth muscle relaxation is mediated through its second messenger cyclic guanosine monophosphate, which is broken by tissue phosphodiesterases (PDEs). Thus the inhibition of cyclic guanosine monophosphate breakdown by PDE inhibitors can potentiate NO‐mediated responses and facilitate pyloric relaxation. In an animal model of diabetes mellitus, treatment with sildenafil (a PDE‐5 inhibitor) restored NO‐mediated pyloric relaxation and improved gastric emptying. The aim of our study was to examine the hypothesis that sildenafil may improve gastric emptying in patients with ESRF and symptoms of gastric paresis.

Differentiated thyroid carcinoma in Children and young adults: Evaluation of response to treatment

Aim: The aim of this study was to evaluate response to treatment of children and young adults with differentiated thyroid carcinoma (DTC). Patients and methods: Thirty-one children and young adults (27 female, 4 male, <25 years) with DTC were treated with radioiodine between 1987 and 2003. All patients had previously undergone total (or near-total) thyroidectomy with lymph node dissection (if enlarged lymph nodes were present). Initial radioiodine therapy was given 4 to 6 weeks after surgery. Repeated doses were given 4 to 6 weeks after l-thyroxine withdrawal. Effect of therapy was evaluated by radioiodine whole-body scans and serum thyroglobulin levels. Results: Age range at diagnosis was 12 to 25 years (median, 21 years). Follow-up duration range was 16 to 150 months (mean, 60 months). Histologic classification was papillary in 28 (90%) patients (follicular variant in 7) and follicular in 3 (10%). Multifocal carcinoma was found in 9 (29%) patients and neck lymph node metastases in 19 (61%) patients. Fifteen (48%) patients had pulmonary or mediastinal metastases at the time of diagnosis, and 1 developed bone metastases. Lung metastases demonstrated a pattern of diffuse radioiodine uptake in 7 patients and focal uptake in 8. Total radioiodine dose range was 80 to 1086 mCi given in 1 to 7 treatments. Fourteen (45%) patients were disease-free, including 1 patient with pulmonary metastases who achieved complete remission. Three (10%) patients had persistent metastases in neck lymph nodes. Nine (29%) patients with pulmonary metastases showed good response, 4 (13%) had stable persistent disease, and 1 had progression of the disease and died after 11.5 years of follow up. All surviving patients (97%) are asymptomatic and leading normal lives. Conclusions: Children and young adults with DTC had a high incidence of multifocal disease, lymph node involvement, and pulmonary metastases. Although complete remission of pulmonary metastases after radioiodine therapy was difficult to achieve, a partial response with reduction of metastatic disease was possible. In general, the patients had a good quality of life with no further disease progression and a low mortality rate.

Follicular variant of papillary thyroid carcinoma: clinical-pathological characterization and long-term follow-up.

PURPOSEQuestions arise concerning the behavior and prognosis of the follicular variant of papillary thyroid carcinoma. PATIENTS AND METHODSBetween 1990 and 2003, 92 patients with follicular variant of papillary carcinoma (group A) were enrolled in a long-term study and compared with control groups of follicular thyroid carcinoma (group B, 40 cases) and pure papillary thyroid carcinoma (group C, 99 subjects). RESULTSGender (female/male), age, and follow-up duration (years, mean ± standard error) in groups B, A, and C were 36/4, 43 ± 3, 11 ± 1.1; 79/13, 46 ± 2, 9.5 ± 0.7; and 82/17, 44 ± 1, 10 ± 0.6, respectively. At the time of diagnosis, the rates of extensive extra thyroidal local spread, bilateral lesions, and vascular invasion were higher in group A than in group C. The rate of metastasis tumors was higher in group A than in group C and was comparable in groups A and B. Complete remission was reported in 95% of group B patients, 98% of group C individuals, and in only 77% of group A subjects. Persistent stable lesions and progressive disease rates in groups B, A, and C were 2.5% and 2.5%, 15% and 8%, and 0% and 2%, respectively. The survival rates at the end of the study were 100% in all cohorts, but the cumulative dose of administered radioiodine in group A was higher than in group C and was comparable to that given in group B. Metastases dedifferentiation was observed only in the group A (three patients). DISCUSSIONFollicular variant of papillary thyroid carcinoma may be more aggressive than previously considered and should be clearly distinguished from the two other forms of well-differentiated thyroid carcinoma.

Double ectopic thyroid

Abstract. Ectopic thyroid gland is a well-known developmental anomaly. We present a child with a unique anatomical variant of this anomaly, namely double ectopic thyroid. The purpose of this report is to demonstrate the scintigraphic findings and to emphasize the importance of performing a thyroid scan in every case of thyroid ectopia to accurately identify all sites of functioning thyroid tissue.

Characteristics of skeletal stress fractures in female military recruits of the Israel defense forces on bone scintigraphy.

Aim: Clinical surveys on stress fractures (SF) in female military recruits are scarce. The aim of this study was to characterize the scintigraphic findings and classify the distribution and pattern of SF in a group of female recruits of the Israel Defense Forces (IDF). Materials and Methods: The bone scans of 146 female recruits (age range, 19–20.6 years) with suspected SF were assessed retrospectively. The SF lesions were classified qualitatively into 4 grades of bone response according to the classification criteria introduced by Zwas et al. SF location and distribution were analyzed, and in several cases, the abnormalities were correlated radiographically. Results: One hundred forty-six female recruits were examined, of which 93 (64%) had bone scan findings of SF with a total of 247 SF. Forty-eight patients (with or without SF) had shin splints, 32 had thigh splints, and 34 had normal scans. Several SF were detected in sites that were not clinically suspected. Thirty-nine percent of the SF were located in the feet (tarsal bones 22.7%, metatarsal 16.2%), 36.8% in tibiae (predominantly in the midthird), 15.7% in femurs, 6.5% in the pubic and sacroiliac regions, and 2% in the fibula. SF in the tibiae and femurs were mainly located in the posterior aspect of the medial cortical region. Forty-nine percent of the patients had bilateral SF. The SF were classified on a 4-grade scale: 41.3% were grade I, 37.2% grade II, 15.8% grade III, and 5.7% grade IV. Thirty-three percent of the patients had one site of SF, 31% had 2 sites, 7.5% had 3 sites, 12% had 4 sites, 7.5% had 5 sites, and 9% had more than 5 sites of SF. Different grades of lesions were often found in the same patient. Sixty-five percent of the patients had SF in the feet, 59% in the tibiae, 26% in the femurs, 14% in the pubic or sacroiliac regions, and 5% in the fibula. Radiography was performed in 15% of the patients. Only one patient had a positive finding on radiography. Conclusions: This study shows that lower leg SF are not uncommon in female military recruits. We clearly distinguished between SF and shin splints, which have important clinical consequences on treatment. Most of the SF were mild (grade I and II) located in the feet and tibiae. This study supports the experience gained in other studies, and emphasizes the significant number of pubic and sacroiliac SF in female soldiers, which is significantly higher in comparison with previous reports on male soldiers.

Diagnosis of normocalcemic hyperparathyroidism by oral calcium loading test

We evaluated the oral calcium-loading test (OCLT) in diagnosing normocalcemic primary hyperparathyroidism. Calcium and PTH levels were measured before, 60, 120 and 180 min after oral 1 g of calcium gluconolactate administration in 102 consecutive females with high circulating PTH levels, and 25 controls. Patients were classified as follows: Group A, patients with a parathyroid adenoma identified by two imaging modalities. Sub-Group AO, hyper-parathyroid patients [no.=13, mean age 59 yr (SD=10)] evaluated prior to parathyroidectomy. Sub-Group AH, non-operated hypercalcemic patients [no.=29, age 63 yr (SD=11)]. Sub-Group AN, normocalcemic non-operated women [no.=14, age 59 yr (SD=8)]. Group B, normo-calcemic individuals [no.=46, age 58 yr (SD=11)] with negative parathyroid imaging. Group C, control patients [no.= 25, age 56 yr (SD= 12)]. The concentrations of calcium and PTH overlapped in the normocalcemic groups during the OCLT. Product P, defined as circulating PTH nadir (pg/ml) × peak calcium concentration (mg/dl), better discriminated Sub-Group AN from Group B, AUC=0.98 (95% CI 0.95, 1.00) than did Ratio R, defined as relative PTH decline/relative calcium increment, AUC= 0.86 (95%CI 0.73, 0.99). Assuming normal threshold of Product P and Ratio R at 260 and 17 respectively, the combined parameters diagnose normocalcemic hyperparathyroid patients with 100% sensitivity and 87% specificity.

99Tcm-MIBI scintimammography for the detection of breast malignancies : The contribution of the count ratio to specificity

We evaluated the efficacy of 99Tcm-sestamibi (MIBI) scintimammography for the detection of breast cancer in 332 patients. Two hundred and seven scans were confirmed by histological or cytological results; the other patients were examined because they belonged to high-risk groups or had dense fibroglandular breasts. Of 207 patients with histological confirmation, 112 positive studies were obtained: 86 true-positive and 26 false-positive. Scintimammography was negative in 95 patients: 88 true-negative and seven false-negative. Six of seven false-negative results were obtained in patients with impalpable tumours. The sensitivity, specificity, positive and negative predictive values were 92.5%, 77.2%, 76.8% and 92.6% respectively. The overall accuracy was 84.1%. To identify false-positive results, the count ratio of the target lesion to the contralateral normal area on 38 true-positive scans and in 26 false-positive examinations was calculated from the region of interest drawn on the 99Tcm-MIBI scan (L/N ratio). A significantly higher ratio was found for the true-positive scans (1.583 +/- 0.501 vs 1.246 +/- 0.213; P = 0.0002). In conclusion, 99Tcm-MIBI scintimammography is a sensitive and accurate method for the detection of breast malignancies.

Detection of rhabdomyolysis associated with compartment syndrome by bone scintigraphy.

A bone scan is rarely needed as a primary method for the assessment of muscle damage, but the finding of muscle uptake should be recognized as an incidental or primary finding when the patient is examined because of a possible osseous lesion. The authors describe a young patient with a painful and edematous right lower extremity. The bone scan did not show any skeletal disease, but markedly increased tracer uptake was seen in a unique pattern in musculature of the lower leg as evidence for rhabdomyolysis associated with an evolving compartment syndrome.

99Tcm-tetrofosmin scintimammography for detecting breast cancer : A comparative study with 99Tcm-MIBI

Scintimammography using 99Tcm-MIBI (99Tcm-sestamibi) has demonstrated promising results in the detection of breast cancer. Recently scintimammography using 99Tcm-tetrofosmin has been suggested as a better diagnostic tool and a more convenient agent to use in this condition. In this study we compared both agents in 35 consecutive women with abnormal mammographic or physical findings. Thirty-four of them underwent MIBI scan, followed by tetrofosmin scan 2 days later (performed on all 35 women). Within 2 weeks, a pathological diagnosis was obtained either by needle or open biopsy. In both scans the uptake ratio between the lesion and the background uptake was calculated. Twenty patients who underwent tetrofosmin scan and 19 patients with MIBI scan had malignant breast tumours, while 15 women had benign lesions. The sensitivity, specificity, positive and negative predictive values and total accuracy of the MIBI scan were 89.4%, 80%, 85%, 85.7% and 85.3%, respectively; almost identical values were obtained with tetrofosmin (90%, 80%, 85.6%, 85.7% and 85.7%, respectively). The uptake ratios in the MIBI and tetrofosmin scans were 1.68±0.52 and 1.7±0.47, respectively. No differences were found between the two scintimammographies in all the parameters examined. In conclusion, MIBI and tetrofosmin breast scans are accurate and equally efficient for the detection of breast malignancies.

False-Negative Meckel's scan caused by a recent barium study.

An 18-year-old girl was hospitalized because of acute gastrointestinal bleeding. A Meckels scan (with Tc-99m pertechnetate) was falsely interpreted as negative for Meckels diverticulum as a result of contrast material attenuation in the lower abdomen after recent enteroclysis with barium. A Tc-99m-labeled red blood cell scan obtained during a second hospitalization was positive for gastrointestinal bleeding in the ileocecal region. A missed Meckels diverticulum was considered the cause of this bleeding, and another Meckels scan was obtained. Surgery after this positive Meckels scan showed a Meckels diverticulum containing gastric mucosa. After barium is used in an evaluation of the gastrointestinal tract, a Meckels scan should be delayed until barium has cleared from the bowel, as documented by radiographic evaluation, or until its clearance would be expected. Repeated examination can improve diagnostic accuracy when this barium pitfall is not avoided.