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Chun K Kim

Publications and source records attributed to Chun K Kim.

30 records · Page 2Linked to original sources
PubMed2003

Areolar-cutaneous "junction" injections to augment sentinel node count activity.

PURPOSE: The authors report on a modified lymphoscintigraphy protocol for increasing activity in the sentinel node (SN) through a specific technique (LymphoBoost). It consists of an areolar-cutaneous "junction" injection, using a very shallow, high-volume, high-specific-activity injection of 100% filtered Tc-99m sulfur colloid, as an adjunct to their standard protocol. MATERIALS AND METHODS: Results from a previously optimized protocol (group 1, n = 28) were compared with those from their new protocol (group 2, n = 85), which consisted of two sets of consecutively applied (within 12 to 20 minutes) injections: group 2A composed of perilesional and intradermal injections (similar to the previous group 1) followed by group 2B LymphoBoost injections within 12 to 20 minutes in the same patients. Regions of interest were drawn around the SN and the injection sites (IS) at the end of the studies to calculate the end-of-study SN:IS ratio for both group 1 and group 2 studies. The SN:IS ratio is generally independent of dose and is a measurement of the "efficiency" of getting activity from the IS to the SN. RESULTS: The mean SN:IS ratio in group 2 was 3.34 times greater than that in group 1 studies (P < 0.0005). The median SN:IS ratio was 3.53 times greater in the group 2 studies. Many cases showed a dramatic increase in SN counts before the LymphoBoost injection was even completed, with more than 5% of injected activity reaching nodes at the end of the study in some patients. Multiple different lymphatic pathways were noted, but all led to the same node(s). No significant disagreement between group 2A and group 2B results was noted. CONCLUSIONS: Areolar-cutaneous junction injections, performed under these conditions, augment SN activity dramatically in most patients. Hotter nodes provide several benefits, especially when next-day surgery is contemplated, and should also reduce the extent of dissection needed to remove the sentinel node.

Breast↗
PubMed2003

The usefulness of a repeat study for differentiating between bowel activity and local tumor recurrence on FDG PET scans.

The importance of fluorodeoxyglucose (FDG) positron emission tomography (PET) in the evaluation of colorectal cancer is well established. Activity in the rectosigmoid region on an FDG PET scan may vary significantly, which may occasionally lead to difficulties in interpretation when assessing local recurrence of colorectal cancer. The authors present a case in which a repeat PET study performed after an enema 1 week later was useful for differentiating between normal bowel activity and local tumor recurrence. This repeat study obviated the need for surgical intervention, although the role of the enema in this case is unclear.

Colon↗
PubMed2003

Factors affecting visualization rates of internal mammary sentinel nodes during lymphoscintigraphy.

UNLABELLED: There is great variation in the reported frequency of internal mammary (IM) sentinel node (SN) visualization. We observed a marked increase in our IM SN detection rate after 2 factors were changed simultaneously: depth of perilesional injection and dose. METHODS: A retrospective review of 82 consecutive patients (group 1) was compared with 61 consecutive patients (group 2) after changing the depth of perilesional injections and dose. Both groups had perilesional injections of (99m)Tc-sulfur colloid followed by intradermal injections at the areolar cutaneous junction. For group 2, activity was increased in all patients scheduled for next-day surgery. Group 2 had perilesional injections on top of, beside, and just below the estimated level of the tumor in an infiltrative manner, versus injections just on top of and beside the tumor as performed for group 1. RESULTS: The rates of IM SN visualization were 4.9% (4/82) for group 1 and 23.0% (14/61) for group 2 (P < 0.003). IM SNs were hotter in group 2 than in group 1. The total number of IM SNs detected per patient was also higher for group 2 than for group 1: 2.1 and 1.2, respectively. In group 2, patients with small breasts had an IM SN visualization rate of 46.2%; those with medium breasts, 21.1%; and those with large breasts, 0% (P < 0.017). In group 2, primary lesions located medially had a higher rate of IM SN visualization than did lesions located laterally: 38.9% (7/18) and 16.2% (6/37), respectively (P = 0.066). Dose was not a statistically significant factor within group 2 or group 1 when comparing IM SN visualization rate for doses above or below the mean or median. CONCLUSION: Modification of just these 2 factors resulted in a striking change in our IM SN detection rates. The injection depth was the most important factor. Breast size had a marked effect on the probability of detecting IM SNs. This suggests that the variation in detection rates reported in the literature could be at least partly dependent on variations in these factors, among others. Many surgeons do not routinely harvest IM SNs, but information about their presence can potentially alter treatment decisions.

Axilla↗
PubMed2002

Radioguidance is not necessary during parathyroidectomy.

BACKGROUND: Improvements in the accuracy of preoperative localization and the availability of the rapid parathyroid hormone assay have permitted minimally invasive parathyroidectomy in patients with primary hyperparathyoidism. HYPOTHESIS: The use of intraoperative radioguidance is beneficial during targeted parathyroid operations. DESIGN: A retrospective analysis of a prospective database of patients. SETTING: Tertiary care referral center. PATIENTS: During a 2(1/2)-year period, 130 patients underwent minimally invasive, targeted parathyroidectomy with intraoperative monitoring of the parathyroid hormone level. Of these, 60 patients underwent radioguided parathyroidectomy. Prior to surgery, a solitary parathyroid adenoma was visualized on technetium Tc 99m sestamibi scintigraphy in all patients selected for radioguided parathyroidectomy. A gamma probe was used to guide the surgical dissection. RESULTS: All patients were cured following radioguided parathyroidectomy. In 29 patients (48%), the probe provided confusing or inaccurate information; however, a unilateral neck exploration with excision of a parathyroid adenoma was successfully completed in each of these patients. Forty-three cases were completed under local anesthesia and 85% were discharged home on the same day of surgery. There was 1 temporary recurrent laryngeal nerve palsy. CONCLUSION: In the era of improved preoperative localization and intraoperative parathyroid hormone monitoring, the routine use of radioguidance is not recommended during parathyroidectomy.

Adenoma↗
PubMed2002

Ultrasonography for preoperative localization of enlarged parathyroid glands in primary hyperparathyroidism: comparison with (99m)technetium sestamibi scintigraphy.

OBJECTIVE: To determine the utility of ultrasonography for the preoperative localization of enlarged parathyroid glands in primary hyperparathyroidism, and to compare this method with (99m)technetium sestamibi scintigraphy. DESIGN: The results of ultrasonography for localization of enlarged parathyroid glands were determined in 120 consecutive patients with primary hyperparathyroidism and compared with findings at surgery (n = 86) and with the results of (99m)technetium sestamibi scintigraphy (n = 99). PATIENTS: All patients had biochemically documented primary hyperparathyroidism based on elevated serum calcium and 'intact' parathyroid hormone measured by immunoassay. Patients with prior parathyroid surgery or secondary hyperparathyroidism were excluded. MEASUREMENTS: High-resolution ultrasonography was performed by a single observer. (99m)Technetium sestamibi scintigraphy was performed using early and delayed (2-h) views, and correlated with simultaneous thyroidal 123I uptake in most patients. RESULTS: Ultrasonography detected putative enlarged parathyroid glands in 92 of 120 unselected patients (77%). It correctly predicted surgical findings in 64 of 86 patients undergoing surgery (74%), including 61 of 72 patients with solitary eutopic parathyroid adenomas (84%), but only two of eight patients with solitary ectopic adenomas, and only one of six patients with multigland parathyroid disease. Sestamibi scintigraphy was positive in 87 of 99 unselected patients (88%), a higher proportion than ultrasonography (P < 0.05), reflecting superior sensitivity for the detection of ectopic parathyroid adenomas. For 74 patients undergoing parathyroid surgery who underwent both imaging tests there was no statistically significant difference between ultrasonography and sestamibi scintigraphy in ability to correctly predict surgical findings (74%vs. 82%, respectively) or in positive predictive value (93%vs. 90%, respectively). However, sestamibi scintigraphy was clearly more sensitive for ectopic parathyroid adenomas, providing correct localization in 8/8 cases. When one test was negative, testing with the second method was usually positive, improving the likelihood of a positive result to 98% when both tests were employed. CONCLUSIONS: Ultrasonography can be a sensitive and accurate method for preoperative localization of enlarged parathyroid glands in primary hyperparathyroidism, comparable in overall utility to sestamibi scintigraphy. These results suggest that a strategy of initial testing with one or the other method, followed by the alternate imaging test if the first test is negative, would provide correct parathyroid imaging in most patients without prior parathyroid surgery.

Adenoma↗
PubMed2002

Repeated bleeding scintigraphy may reveal that stationary foci of activity represent sites of active hemorrhage.

The goal of bleeding scintigraphy is to localize the site of origin of a hemorrhage to within general regions of the large or small bowel. Activity is typically seen to extravasate from the blood pool into the lumen, and the collection of activity then moves on sequential images, as a result of the cathartic action of blood. Sometimes, bleeding studies show a stationary focus of activity without subsequent movement. It is generally assumed that these foci represent fixed structures, such as the urinary tract or prominent vasculature, rather than acute extravasation of labeled blood into the bowel. The authors report three cases in which repeated studies showed that fixed foci of activity were, in fact, related to gastrointestinal bleeding. In two instances, the fixed foci represented extravasated blood that, for unexplained reasons, did not move during the study. In an additional case, the fixed activity visualized was ultimately shown to be prominent varices, which were implicated in the bleeding. Recognition of these possibilities, and consideration of possible strategies to localize the bleeding site further, should facilitate optimal patient treatment.

Aged↗
PubMed2002

Effect of high specific-activity sulfur colloid preparations on sentinel node count rates.

PURPOSE: Preliminary results by other investigators suggest that increasing the specific activity of Tc-99m nanocolloid preparations increases the measured counts in sentinel nodes compared with lower specific-activity (SA) preparations using the same initial injected dose. The authors set out to determine whether a similar result could be perceived with Tc-99m sulfur colloid (SC) preparations. METHODS: Twenty-three consecutive patients (low SA group) with successful visualization of sentinel nodes by lymphoscintigraphy before our standard protocol was changed to a higher SA preparation were compared with 28 patients (high SA group) just after the switch. Injection techniques were similar in both groups: peritumoral injections at two to four points of a mixture of half-filtered (0.22 microm filter) and unfiltered Tc-99m sulfur colloid in 6 ml followed immediately by intradermal injections of filtered sulfur colloid above the tumor. Activity levels for both types of injections ranged from 3.7 to 11.1 mBq (100 to 300 microCi). Preparation of the higher SA mixture of sulfur colloid was achieved by using only one eighth of the sulfur colloid vial contents when the same activity (125 mCi) of Tc-99 was added. Regions of interest were drawn around the images of sentinel nodes and the initial injection site in the anterior and lateral projections. Ratios of sentinel node to initial injection site count were calculated for both groups. RESULTS: The mean ratio of sentinel node to injection site count in the high SA group was 2.9 times greater than that in the low SA group. The median ratio value was 2.7 times greater in the high SA group. CONCLUSION: These preliminary results suggest higher counts in the sentinel node are possible with a higher SA preparation.

Breast Neoplasms↗
PubMed2002

The efficacy of sestamibi parathyroid scintigraphy for directing surgical approaches based on modified interpretation criteria.

PURPOSE: With the increasing use of targeted parathyroidectomy, the accuracy of sestamibi parathyroid scintigraphy (SPS) in determining the best surgical approach has become more clinically relevant than its sensitivity for detecting all abnormal glands. The reported accuracy of SPS does not represent the true efficacy of SPS for directing targeted parathyroidectomy, because many authors reported accuracy on the basis of abnormal glands. The authors assessed the efficacy of SPS based on modified interpretation criteria to determine specifically whether SPS influences the surgeon's choice of a targeted versus a conventional approach to parathyroidectomy. METHODS: The authors reviewed the SPS studies (both dual-isotope subtraction and Tc-99m sestamibi dual-phase techniques) performed in 80 patients with primary hyperparathyroidism. All patients had surgery with histologic diagnoses, intraoperative PTH assays, and clinical follow-up. RESULTS: Of 75 patients with solitary adenomas, 9 SPS studies were negative, equivocal, or showed two or more foci, and 66 studies showed a solitary focus on the correct side. Of these 66 studies, 63 showed a lesion in the correct quadrant (e.g., superior or inferior) and 3 predicted the correct side only but a wrong quadrant. The positive-predictive value of SPS was 100% for correctly identifying the side of the adenoma (thus correctly directing unilateral surgery) and 95.5% for correctly identifying the quadrant of the solitary adenoma. CONCLUSION: The positive-predictive value of SPS for directing the surgical approach (but not for detecting individual lesions) that reveals a single focus is very high based on our modified interpretation criteria.

Adenoma↗
PubMedDate not supplied

Extremely indirect dermal lymphatic channels: value of areolar-cutaneous junction injection technique for breast lymphoscintigraphy.

This case describes a patient who initially had peri-excisional injections of radiocolloid around a lumpectomy site that failed to visualize sentinel nodes during lymphoscintigraphy. After additional areolar-cutaneous junction injections, extremely indirect dermal lymphatic pathways were evident with resultant drainage to two sentinel nodes, both of which contained disease. Hybrid combination injections of radiotracer during sentinel lymph node biopsy is gaining in popularity. This case illustrates the validity of the hybrid injection techniques and the demonstrated accuracy despite seemingly disconnected and extremely tortuous pathways as demonstrated in the figure.

Aged↗
PubMedDate not supplied

Clinical breast lymphoscintigraphy: optimal techniques for performing studies, image atlas, and analysis of images.

Breast lymphoscintigraphy is increasingly performed before surgery to delineate the drainage to the sentinel node (SN) in the axilla. On the basis of the histologic status of harvested SNs, the disease status of the entire axilla can be predicted. This prediction allows a more limited dissection to be performed while maintaining staging accuracy comparable with that of classic axillary lymph node dissection. Lymphoscintigraphy assists surgeons in harvesting the SN during gamma probe-assisted axillary biopsy or dissection and provides a wide field of view survey, among other benefits. When certain injection protocols are used, lymphoscintigraphy can be performed in the afternoon before surgery the next morning, thus minimizing disruptions of tight surgical schedules. Image acquisition can be optimized and SN activity can be maximized by means of such factors as parameters for preparation of the radiotracer, injection techniques, energy settings for the gamma camera, breast displacement maneuvers, and techniques for marking and outlining the patient's body. The ultimate goals are to delineate the true SN, maximize activity in the node for facilitated removal (even at next-day surgery), and deliver the information to the surgeon without delaying the surgical schedule.

Artifacts↗