The European strategy for accelerator-based photon science

The League of European Accelerator-based Photon Sources (LEAPS), comprising 19 large-scale user facilities in 10 member and associated states, has put forward for the first time a European strategy for a transformative way of cooperation, thereby mobilizing the members' substantial expertise in photon science and technology, in infrastructure management and service to users and stakeholders. This European Strategy for Accelerator-based Photon Sources-ESAPS 2022-is a coherent pan-European plan addressing the future challenges and needs of the new era in research and innovation, designed to put Europe in a global leadership position in important future key technologies. In ESAPS2022, ambitious facility upgrades and technology development plans as well as a new strategic challenge-driven use of these facilities are discussed.

Simulation of FEL pulse length calculation with THz streaking method

Having accurate and comprehensive photon diagnostics for the X-ray pulses delivered by free-electron laser (FEL) facilities is of utmost importance. Along with various parameters of the photon beam (such as photon energy, beam intensity, etc.), the pulse length measurements are particularly useful both for the machine operators to measure the beam parameters and monitor the stability of the machine performance, and for the users carrying out pump-probe experiments at such facilities to better understand their measurement results. One of the most promising pulse length measurement techniques used for photon diagnostics is the THz streak camera which is capable of simultaneously measuring the lengths of the photon pulses and their arrival times with respect to the pump laser. This work presents simulations of a THz streak camera performance. The simulation procedure utilizes FEL pulses with two different photon energies in hard and soft X-ray regions, respectively. It recreates the energy spectra of the photoelectrons produced by the photon pulses and streaks them by a single-cycle THz pulse. Following the pulse-retrieval procedure of the THz streak camera, the lengths were calculated from the streaked spectra. To validate the pulse length calculation procedure, the precision and the accuracy of the method were estimated for streaking configuration corresponding to previously performed experiments. The obtained results show that for the discussed setup the method is capable of measuring FEL pulses with about a femtosecond accuracy and precision.

High-precision x-ray FEL pulse arrival time measurements at SACLA by a THz streak camera with Xe clusters

The accurate measurement of the arrival time of a hard X-ray free electron laser (FEL) pulse with respect to a laser is of utmost importance for pump-probe experiments proposed or carried out at FEL facilities around the world. This manuscript presents the latest device to meet this challenge, a THz streak camera using Xe gas clusters, capable of pulse arrival time measurements with an estimated accuracy of several femtoseconds. An experiment performed at SACLA demonstrates the performance of the device at photon energies between 5 and 10 keV with variable photon beam parameters.

Resection margins in ultrasound-guided breast-conserving surgery

BACKGROUND

Few published studies have shown the benefits of intraoperative ultrasound in avoiding inadequate margins in breast-conserving surgery. The aim of this study is to quantify intraoperative ultrasound margin size and assess its relationship to tumor size, multifocality, palpability, histology, and presence of intraductal component.

METHODS

Patients with breast cancer undergoing breast-conserving surgery in whom the operating surgeon visualized the tumor by ultrasound were included. Ultrasound margins measured intraoperatively were prospectively recorded and compared with pathology margins.

RESULTS

Forty-five patients with 48 tumors were included. Twenty five patients (56%) had palpable tumors. Pathologic mean tumor size was 1.9 cm [95% confidence interval (CI) 1.6-2.2 cm, range 0.5-4.8 cm]. There was good correlation between closest margins recorded by ultrasound and pathology margins (r = 0.4674, P < 0.0008). Fourteen patients (31%) had margins re-excised intraoperatively, 12 of them in the direction of the closest pathological margin. Three patients (7%), all of whom had intraoperative re-excision, had a second operation for involved margins without residual cancer on pathological examination of the reoperative specimens. Ultrasound margins ≥0.5 cm achieved adequate pathology margins of ≥0.2 cm in 95% of margins. Overestimation of pathology margins by ultrasound measurement was significantly affected by multifocality (P = 0.0473). Tumor size, palpability, invasive lobular histology, and presence of ductal carcinoma in situ (DCIS) did not cause significant overestimation of pathology margins by ultrasound.

CONCLUSIONS

Intraoperative ultrasound may help maintain a low level of reoperation after breast-conserving surgery. Ultrasound margins <0.5 cm should be re-excised intraoperatively. Reliability of ultrasound in predicting the closest pathology margins was diminished in patients with multifocal tumors.

Laser-photofield emission from needle cathodes for low-emittance electron beams

Illumination of a ZrC needle with short laser pulses (16 ps, 266 nm) while high voltage pulses (-60 kV, 2 ns, 30 Hz) are applied, produces photo-field emitted electron bunches. The electric field is high and varies rapidly over the needle surface so that quantum efficiency (QE) near the apex can be much higher than for a flat photocathode due to the Schottky effect. Up to 150 pC (2.9 A peak current) have been extracted by photo-field emission from a ZrC needle. The effective emitting area has an estimated radius below 50 microm leading to a theoretical intrinsic emittance below 0.05 mm mrad.

Intraoperative Palpation for Clinically Suspicious Axillary Sentinel Lymph Nodes Reduces the False-Negative Rate of Sentinel Lymph Node Biopsy in Breast Cancer

Axillary sentinel lymph node biopsy (SLNB) is widely used to identify the first lymph node draining breast tumors. When the sentinel lymph node is free of metastasis, axillary dissection is avoided because the rest of the nodes are expected to be negative as well. A false-negative rate of 5% is considered acceptable. In the case of a false-negative SLNB, adjuvant local and systemic treatments might be suboptimal. We assessed the effect of intraoperative axillary palpation for clinically suspicious lymph nodes that are not otherwise detected by radioactive tracer or blue dye on the false-negative rate of SLNB in breast cancer patients. Our prospective database of patients having surgery for primary invasive breast cancer and who had a SLNB from 2000 to 2004 was reviewed. Only patients with clinically negative nodes preoperatively were included. The procedure included preoperative injection of radiotracer, with dye injection as backup, and intraoperative palpation of the axilla for suspicious lymph nodes that were not radioactive or blue. Of the 290 patients, 89 (30.7%) had sentinel node involvement by tumor. Seven patients had clinically suspicious nodes identified solely by palpation and not by tracer, in addition to sentinel lymph nodes detected by tracer. In five of the seven patients, the nodes harbored metastasis. In four of these five patients (4.5% of the 89 patients with axillary involvement), the palpable nodes were the only ones involved. A generous axillary incision and systematic palpation of the axilla reduces the false-negative rate and should be a part of the SLNB procedure.

Increased mammographic screening and use of percutaneous image-guided core biopsy in non-palpable breast cancer: impact on surgical treatment

BACKGROUND

Major efforts are being directed at the early diagnosis of breast cancer. The diagnosis rate of non-palpable tumors is steadily growing as a result of increased screening by mammography. In most patients with non-palpable lesions, percutaneous image-guided biopsies have replaced wire localization with surgical excision for obtaining tissue diagnosis. In recent years the Israel Ministry of Health initiated a mammograpy screening program. Percutaneous image-guided biopsies have also become widely available.

OBJECTIVE

To assess the impact of these changes on breast cancer surgical treatment in our hospital.

METHODS

The charts of 483 patients operated on in our department for primary breast carcinoma during the years 1997 to mid-2001 were reviewed. Data on the mode of diagnosis, tumor stage, resection margins, and number and types of operations were recorded and analyzed. The term non-palpable tumors relates to tumors necessitating wire localization for surgical excision.

RESULTS

The percentage of patients diagnosed with non-palpable tumors rose from 16.2% in 1997 to 47.4% in 2001, with an average size of 2.6 cm for palpable and 1.7 cm for non-palpable tumors. The rate of preoperative diagnosis for non-palpable tumors rose from 6.2% in 1997 to 96.4% in 2001. The rate of involved or very close margins was reduced by 73% in the patient group diagnosed preoperatively as compared to those without a preoperative diagnosis (10.6% vs. 39.4%). Finally, the percentage of patients who had two operations fell from 56.2% in 1997 to 11.1% in 2001.

CONCLUSIONS

The mammography screening program in Jerusalem in 1997-2001 was effective in increasing the relative percentage of non-palpable breast cancers with reduced tumor size at diagnosis. The improved availability of preoperative tissue diagnosis in these patients reduced the number of surgical procedures needed.

Bowel Intussusception Caused by a Single Clear Cell Renal Cell Carcinoma Metastasis

A 70-year-old white woman presented with small bowel intussusception due to metastasis of renal cell carcinoma (RCC) acting as a leading point. The patient had undergone nephrectomy seven years previously. Metastatic work-up showed no additional metastases. Only three previously publicized cases of a similar kind were found. Intussusception brought about by a metastasis to the bowel wall is rare, but should be borne in mind.

Collagen injections for aging skin lines (wrinkles)

It appears that benefit from collagen injections accrued to a large percentage of patients who responded to our questionnaire. It is interesting that 70% did not forward any information. Of those who reported benefit, the benefit lasted less than a year and was, in fact, within the 6-month range. Still, a large percentage of those responding were enthusiastic about further injections to correct their wrinkling.

Pathophysiology of mid-oesophageal and epiphrenic diverticula of the oesophagus

Thirty-four patients with mid-oesophageal and epiphrenic diverticula were studied radiologically and manometrically. All patients had a motility disorder and gastro-oesophageal reflux was the usual precipitating factor. Most patients can be treated conservatively. In patients who do not respond to medical treatment surgery is necessary. The importance of surgical correction of the physiological abnormality should complement diverticulectomy.

Prepyloric diaphragm, an unusual case of gastric outlet syndrome

The prepyloric diaphragm is a rare entity, with well-established anatomicopathological features but of unknown etiology. Approximately half of the 180 cases described occurred in children. The clinical presentation may be a chronic partial obstruction as in pyloric stenosis, or a complete gastric outlet obstruction when the orifice of the diaphragm is very small or nonexistent. Despite the variable clinical picture, radiological and endoscopic examinations may reveal typical pathognomonic features. With cases being reported more frequently, the treatment had changed from a wholly surgical approach to the introduction of endoscopic web incision and conservative treatment. We report a case diagnosis during surgery, and review the pertinent literature.

Chest wall reconstruction following resection of chondrosarcoma of the sternum

Resection of large portions of the thoracic wall, during the treatment of neoplasms of that area, results in defects which are difficult to reconstruct. Synthetic nets have been used with different results, mainly because of problems of rejection and infection. We successfully used a silicone implant for the treatment of a case of chondrosarcoma of the sternum and ribs.

Clinical evaluation of a new erythromycin solution for acne vulgaris

The effects of a 1.5 percent solution of erythromycin, especially formulated for the topical treatment of acne vulgaris, were compared with those of its vehicle in a twelve week, double-blind study involving twenty-six patients. A statistically significant difference between the responses to the two treatments was seen in both lesion counts and overall evaluations. The final reductions in the mean number of papules and pustules in the erythromycin group were 70.8 and 77.6 percent of the initial values, respectively, and the overall evaluations of this group showed that 91.7 percent of the patients had achieved good or excellent results. A group of fourteen patients continued therapy with the erythromycin solution for an additional nine months. Effective control of their acne was maintained, and no serious side effects were observed.

Cystic hamartoma of Brunner's glands

A 64-year-old white man was operated on for acute gastrointestinal bleeding. The patient was known to have a duodenal polyp for 15 years. Surgery revealed a small duodenal ulcer and a large cystic hamartoma of Brunner's glands. Incidence, aspects of pathogenesis, clinical features and treatment of this rare tumor are discussed.