An operative gamma camera for sentinel lymph node procedure in case of breast cancer

Large field of view gamma cameras are widely used to perform lymphoscintigraphy in the sentinel lymph nodes (SLN) procedure in case of breast cancer. However, they are not specified for this application and their sizes do not enable their use in the operative room to control the excision of the all SLN. We present the results obtained with a prototype of a new mini gamma camera developed especially for the operative lymphoscintigraphy of the axillary area in case of breast cancer. This prototype is composed of 10 mm thick parallel lead collimator, a 2 mm thick GSO:Ce inorganic scintillating crystal from Hitachi and a Hamamatsu H8500 flat panel multianode (64 channels) photomultiplier tube (MAPMT) equipped with a dedicated electronics. Its actual field of view is 50 × 50mm2. The gamma interaction position in the GSO scintillating plate is obtained by calculating the center of gravity of the fired MAPMT channels. The measurements performed with this prototype demonstrate the usefulness of this mini gamma camera for the pre, per and post-operative identification of SLN's and how its complementary role with an intraoperative handheld gamma probe enables to improve the efficiency of this practice. A 100 × 100mm2 field of view camera designated to cover the entire axillary area is under investigation

Optimization of sentinel lymph node biopsy in breast cancer using an operative gamma camera

<p>Abstract</p> <p>Background</p> <p>Sentinel lymph node (SLN) procedure is now a widely accepted method of LN staging in selected invasive breast cancers (unifocal, size ≤ 2 cm, clinically N0, without previous treatment). Complete axillary clearance is no longer needed if the SLN is negative. However, the oncological safety of this procedure remains to be addressed in randomized clinical trials. One main pitfall is the failure to visualize SLN, resulting in incorrect tumor staging, leading to suboptimal treatment or axillary recurrence. Operative gamma cameras have therefore been developed to optimize the SLN visualization and the quality control of surgery.</p> <p>Case presentation</p> <p>A 44-year-old female patient with a 14-mm infiltrative ductal carcinoma underwent the SLN procedure. An operative gamma camera was used during and after the surgery. The conventional lymphoscintigraphy showed only one SLN, which was also detected by the operative gamma camera, then removed and measured (9.6 kBq). It was analyzed by frozen sections, showing no cancer cells. During this analysis, the exploration of the axillary area with the operative gamma camera enabled the identification of a second SLN with low activity (0.5 kBq) that conventional lymphoscintigraphy, surgical probe and blue staining had failed to visualize. Histological examination revealed a macrometastasis. Axillary clearance was then performed, followed by a postoperative image proving that no SLN remained. Therefore, the use of the operative gamma camera prevented an under-estimation of staging which would have resulted in a suboptimal treatment for this patient.</p> <p>Conclusion</p> <p>This case report illustrates that an efficient operative gamma camera may be able to decrease the risk of false negative rate of the SLN procedure, and could be an additional tool to control the quality of the surgery.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov Identifier: NCT00357487</p

Web tension control in an industrial accumulator

This paper presents the study of an industrial accumulator used in a web transport system. In order to understand the main characteristics of the accumulator and the causes of problems appearing during transient phases, different models based on physical laws have been built.Different approaches are tested to calculate the web tension between two rolls. The selected approach uses an empirical law to express the web tension as a function of the downstream span tension and the difference of velocities between consecutive rolls. The empirical law aims to respect the mechanical behavior and the tension and velocity conditions imposed at the entry and the exit of the accumulator, which is not realized in classical web transport modeling.One actuator is available to maintain the web tension approximately constant in the whole accumulator during the accumulator descent. Experiments and simulations have permitted to show that the existing industrial PI control of the web tension is not very satisfactory. The comparison of the PI control with a multivariable control (H(infinity) robust control) is presented. To improve the accumulator operation, new approaches are suggested, such as modifying the input parameter or introducing a mechanical tension regulator

Oleogranulomatous Mastitis: A Topical Subject:

Paraffin and petrolatum have been known for more than 100 years as volumizing products. Certain countries still use them despite important complications. The authors report the case of a 39-year-old patient presenting a bilateral oleogranulomatous mastitis. An injection of petrolatum had been realized 2 years ago in Chechnya for cosmetic reasons. Clinically, she presented dense, erythemic, and painful breasts. The radiological examination found diffuse oily cysts. After first abdominal expansion, a bilateral mastectomy with immediate reconstruction was performed. The authors present a literature review about the clinical and radiological data and the possible treatments, and underline the numerous risks of this procedure, which should be strictly forbidden