Desmoid-type fibromatosis

International Nuclear Information System (INIS)

Otero, S.; Moskovic, E.C.; Strauss, D.C.; Benson, C.; Miah, A.B.; Thway, K.; Messiou, C.

2015-01-01

Desmoid-type fibromatosis is a rare, locally infiltrative, mesenchymal neoplasm that is associated with high rates of local recurrence but lacks the potential to metastasise. The disease affects younger individuals, with a peak age of 30 years, and is the most common cause of an anterior abdominal wall mass in young women of childbearing age. It may, however, involve nearly every body part, including the extremities, head and neck, trunk, and abdominal cavity; as such, desmoid-type fibromatosis may present to a range of general and subspecialty radiologists. These rare tumours have a widely variable clinical presentation and unpredictable natural history, hence input from a soft-tissue tumour centre is recommended, although much of the imaging may be performed at the patient's local hospital. The consensus for treatment has changed over the past decade, with most centres moving away from primary radical surgery towards a front-line ‘watch-and-wait’ policy. Therefore, imaging has an increasingly important role to play in both the diagnosis and follow-up of these patients. This review will discuss the typical imaging characteristics of these lesions and suggest diagnostic and follow-up magnetic resonance imaging protocols, with details of suitable sequences and scanning intervals

Idiopathic gingival fibromatosis

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Sujata Rath

2011-01-01

This article presents a case report of a 14-year-old female patient with idiopathic gingival fibromatosis in the maxillary region with radiographic feature of congenitally missing maxillary permanent left lateral incisor, maxillary left and right permanent canine, mandibular right second premolar, all third molars along with overretained primary maxillary left lateral incisor and primary mandibular second molar. The treatment rendered in this patient comprised of surgical excision of the hyperplasia under general anesthesia.

Giant mesenteric fibromatosis – A case report

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Liana Pleș

2017-05-01

Full Text Available Mesenteric fibromatosis or intra-abdominal desmoids tumor is a rare clinical entity. It is a locally aggressive tumor but not metastasizing proliferation. We report a case of a 27-year-old woman with no significant medical and a previous cesarean section, admitted for abdominal pain. The CT abdominal evaluation revealed subserosal uterine fibroid. The patient underwent an elective laparotomy and a mass measuring 20/15/15 cm in diameter to the medial wall of the cecum was discovered. Complete removal was accomplished with right hemicolectomy. Histopathological examination reported mesenteric fibromatosis. Postoperatively, patient was well and 6 month follow-up showed good recovery. Moreover the next month she became pregnant and the pregnancy and birth were uneventful.

Hyaline fibromatosis syndrome (juvenile hyaline fibromatosis). Whole-body MR findings in two siblings with different subcutaneous nodules distribution

International Nuclear Information System (INIS)

Castiglione, Davide; Terranova, Maria Chiara; Picone, Dario; Lo Re, Giuseppe; Salerno, Sergio

2018-01-01

Hyaline fibromatosis syndrome (juvenile hyaline fibromatosis) is a rare, progressive, autosomal recessive disorder whose main hallmark is the deposition of amorphous hyaline material in soft tissues, with an evolutionary course and health impairment. It may present involvement of subcutaneous or periskeletal soft tissue, or may develop as a visceral infiltration entity with poor prognosis. Very few radiological data about this inherited condition have been reported, due to the extreme rarity of disease. We herein present a case of two siblings, affected by different severity of the disease, with different clinical features. They were examined by whole-body MR (WBMR) in order to assess different lesions localization, to rule out any visceral involvement and any other associated anomalies and to define patients' management. (orig.)

Hyaline fibromatosis syndrome (juvenile hyaline fibromatosis). Whole-body MR findings in two siblings with different subcutaneous nodules distribution

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Castiglione, Davide; Terranova, Maria Chiara; Picone, Dario; Lo Re, Giuseppe; Salerno, Sergio [Policlinico, Universita degli Studi di Palermo, Dipartimento di Biopatologia e Biotecnologie Mediche, Palermo (Italy)

2018-03-15

Hyaline fibromatosis syndrome (juvenile hyaline fibromatosis) is a rare, progressive, autosomal recessive disorder whose main hallmark is the deposition of amorphous hyaline material in soft tissues, with an evolutionary course and health impairment. It may present involvement of subcutaneous or periskeletal soft tissue, or may develop as a visceral infiltration entity with poor prognosis. Very few radiological data about this inherited condition have been reported, due to the extreme rarity of disease. We herein present a case of two siblings, affected by different severity of the disease, with different clinical features. They were examined by whole-body MR (WBMR) in order to assess different lesions localization, to rule out any visceral involvement and any other associated anomalies and to define patients' management. (orig.)

Idiopathic Retroperitoneal Hematoma

African Journals Online (AJOL)

6. Stewart BT, McLaughlin SJ, Thompson GA. Spontaneous retroperitoneal haemorrhage:a general surgeon's perspective. Aust N. Z J Surg 1998;68:371-3. Monib, et al.: Idiopathic retroperitoneal hematoma. How to cite this article: Monib S, Ritchie A, Thabet E. Idiopathic retroperitoneal hematoma. J Surg Tech Case Report ...

Hyaline fibromatosis of Hoffa's fat pad in a patient with a mild type of hyaline fibromatosis syndrome

International Nuclear Information System (INIS)

Raak, Sjoerd M. van; Meuffels, Duncan E.; Leenders, Geert J.L.H. van; Oei, Edwin H.G.

2014-01-01

Hyaline fibromatosis syndrome (HFS) is a rare, homozygous, autosomal recessive disease, characterized by deposition of hyaline material in skin and other organs, resulting in esthetic problems, disability, and potential life-threatening complications. Most patients become clinically apparent in the first few years of life, and the disorder typically progresses with the appearance of new lesions. We describe a rare case of a 20-year-old patient with juvenile-onset mild HFS who presented with a history of progressive anterior knee pain. Detailed magnetic resonance (MR) imaging findings with histopathological correlation are presented of hyaline fibromatosis of Hoffa's fat pad, including differential diagnosis. The diagnosis of HFS is generally made on basis of clinical and histopathological findings. Imaging findings, however, may contribute to the correct diagnosis in patients who present with a less typical clinical course of HFS. (orig.)

FIBROMATOSIS (DESMOID TUMOR OF THE BREAST. Fibromatosis (tumor desmoide de mama

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Zhaneta P Boceska

2016-03-01

Full Text Available El tumor desmoide (fibromatosis es una entidad patológica extremadamente rara que se desarrolla de la fascia muscular y la aponeusorsis. Aunque sin potencial metastático, estos tumores son localmente muy agresivos y tienden a infiltrarse en los tejidos circundantes. Nosotros presentamos un caso de tumour desmoide de mama, que tuvo apariencias clínicas sugestivas a carcinoma. La paciente, de 56 años presentó una masa palpable de mama derecho. La citología por aspiracion con aguja fina (AGF no detectó ninguna célula maligna, por lo que se hizo una escisión local conservadora. La paciente no recibió ningun tratamiento postoperatorio adicional, y continúa viva y sana en los siguientes 18 meses. Desmoid tumor (fibromatosis is extremely rare benign pathological entity that develops from muscular fasciae and aponeuroses. Although without metastatic potential, these tumors are locally very aggressive and tend to infiltrate the surrounding tissues. We present a case of a desmoid tumor of the breast that had clinical appearance suggestive of carcinoma. The patient was 56 years old female with a previous history of surgical trauma who presented with a palpable mass in the right breast. A fine needle aspiration (FNA cytology did not reveal any malignant cells, thus conservative local excision was performed. The patient did not receive any additional postoperative treatment and was alive and free of disease after 18 months of follow-up. 

Hyaline fibromatosis of Hoffa's fat pad in a patient with a mild type of hyaline fibromatosis syndrome

Energy Technology Data Exchange (ETDEWEB)

Raak, Sjoerd M. van [Albert Schweitzer Hospital, Department of Radiology, Dordrecht (Netherlands); Meuffels, Duncan E. [Erasmus MC - University Medical Center, Department of Orthopaedic Surgery, Rotterdam (Netherlands); Leenders, Geert J.L.H. van [Erasmus MC - University Medical Center, Department of Pathology, Rotterdam (Netherlands); Oei, Edwin H.G. [Erasmus MC - University Medical Center, Department of Radiology, Rotterdam (Netherlands)

2014-04-15

Hyaline fibromatosis syndrome (HFS) is a rare, homozygous, autosomal recessive disease, characterized by deposition of hyaline material in skin and other organs, resulting in esthetic problems, disability, and potential life-threatening complications. Most patients become clinically apparent in the first few years of life, and the disorder typically progresses with the appearance of new lesions. We describe a rare case of a 20-year-old patient with juvenile-onset mild HFS who presented with a history of progressive anterior knee pain. Detailed magnetic resonance (MR) imaging findings with histopathological correlation are presented of hyaline fibromatosis of Hoffa's fat pad, including differential diagnosis. The diagnosis of HFS is generally made on basis of clinical and histopathological findings. Imaging findings, however, may contribute to the correct diagnosis in patients who present with a less typical clinical course of HFS. (orig.)

Recurrent Primary Fibromatosis in the Breast: A Case Report

International Nuclear Information System (INIS)

Lim, Soo Jin; Kang, Young Hae; Lee, Ju Won; Kim, Youn Jeong; Kim, Lucia; Cho, Young Up

2012-01-01

Fibromatosis is a rare benign tumor that presents predominantly as a unilateral, painless, palpable, and firm to hard mass which may be accompanied by skin dimpling and nipple retraction. It is characterized as an infiltrating fibroblastic and myofibroblastic proliferation that can behave in a locally aggressive fashion if incompletely excised. However, it is not known to metastasize. We report a case of a 39-year-old female with recurrent fibromatosis in the breast. Initially, the mass was detected by a screening mammography. It appeared as an oval mass and recurred twice after surgical excision over a 36-month period with a more suspicious appearance.

Case report: Fibromatosis colli in a neonate

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Smiti S

2010-01-01

Full Text Available Fibromatosis colli or pseudotumor of infancy of the sternocleidomastoid muscle is a rare cause of a benign neck mass in neonates and infants. If diagnosed correctly, it can be managed conservatively, and unnecessary investigations can be avoided.

F 18 FDG PET/CT Findings of Spontaneous Mesenteric Fibromatosis in a Patient with Gardner's Syndrome

International Nuclear Information System (INIS)

Sohn, Myung Hee; Jeong, Young Jin; Lim, Seok Tae; Kim, Dong Wook; Jeong, Hwan Jeong; Yim, Chang Yeol

2011-01-01

Gardner's syndrome (GS), a variant of familial adenomatous polyposis, is an autosomal dominant disease. Originally, Gardner described a syndrome consisting of hereditary intestinal polyposis With osteomas and multiple cutaneous and subcutaneous lesions. The syndrome was later modified by the addition of other features, such as dental abnormalities, abdominal fibromatosis, and a number of malignant tumors. the principal cutaneous lesions that have been described in GS are epidermoid cysts. Other cutaneous lesions include fibromas, lipomas, leiomyomas, neurofibromas, and pigmented skin lesions. Fibromatoses are histologically benign, but locally aggressive fibrous tumors consisting of mature fibroblasts within an extensive collagen matrix. Most cases are sporadic, but there is a clear association with familial adenomatous polyposis and GS, suggesting a link with a mutation of the APC gene on chromosome 5q22. Fibromatosis occurs in 3.5%-29% of patients with GS, and is more likely to be multiple and to involve the mesentery and abdominal wall rather than being an isolated form. Clinically, fibromatosis presents as a painless firm soft tissue mass. Most cases of fibromatosis are believed to be precipitated by surgical trauma, however, a few cases of spontaneous occurrence have been reported. In our patient, no history of abdominal surgery or trauma was present. In addition, an abdominal CT obtained 2 years ago revealed no abnormality. Although the radiological features of fibromatosis on CT or MR have been described in the literature, F 18 FDG PET or PET/CT findings are rarely reported. The F 18 FDG uptake in patients with fibromatosis ranged from low to moderate grade and was generally heterogenous with a few tiny foci of relatively intense uptake or relatively homogenous. The areas of higher FDG metabolism are likely to represent more cellular and mitotically active areas. Mesenteric fibromatosis has similar findings to extra abdominal lesions.

Rapid Spontaneous Resolution of Fibromatosis Colli in a 3-Week-Old Girl

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Paolo Adamoli

2014-01-01

Full Text Available Fibromatosis colli is an uncommon benign, congenital fibrous tumor or pseudotumor of the sternocleidomastoid muscle that manifests in infancy. In some of these patients tightening of the muscle results in torticollis. We report the case of a 3-week-old child, who presented with a neck mass localized in the left side with reduced mobility of the head. The diagnosis of fibromatosis colli was raised by ultrasound sonography. The mass regressed spontaneously within 3 months without surgical or physical treatment.

Idiopathic Retroperitoneal Hematoma

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Tomoyuki Abe

2010-09-01

Full Text Available A 34-year-old female presented with sudden onset of severe abdominal pain in a flank distribution. A large mass was palpable in the right upper quadrant on physical examination. Abdominal contrast-enhanced computed tomography showed a well-defined, right-sided, retroperitoneal cystic lesion located between the abdominal aorta and the inferior vena cava (IVC. The tumor size was 55 × 58 mm, and it compressed the gallbladder and the duodenum. Upper gastrointestinal radiography revealed a stricture of the second portion of the duodenum by the tumor. T2-weighted magnetic resonance imaging showed that the whole part was hyperintense with hypointense rims, but the inner was partially hypointense. Based on the radiological findings, the preoperative differential diagnosis included retroperitoneal teratoma, Schwannoma, abscess, and primary retroperitoneal tumor. On laparotomy, the tumor was located in the right retroperitoneal cavity. Kocher maneuver and medial visceral rotation, which consists of medial reflection of the upper part of right colon and duodenum by incising their lateral peritoneal attachments, were performed. Although a slight adhesion to the IVC was detected, the tumor was removed safely. Thin-section histopathology examination detected neither tumor tissues nor any tissues such as adrenal gland, ovarian tissue, or endometrial implants. The final pathological diagnosis was idiopathic retroperitoneal hematoma; the origin of the bleeding was unclear. The patient was discharged without any complication 5 days after the operation.

Radiologic images of an aggressive implant-associated fibromatosis of the breast and chest wall: case report and review of the literature

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Lourdes Alanis, MD, MPH

2017-09-01

Full Text Available Fibromatosis of the breast is a rare benign disease compromising <0.2% of all primary breast tumors. Although the chest wall is a common location, occurrences of implant-associated fibromatosis of the breast are extremely rare; only 33 cases have been reported. We present a case of a 42-year-old female who underwent breast augmentation with silicone breast implants, and 2 years later developed an aggressive implant-associated fibromatosis of the breast and chest wall. On imaging studies, the tumor mimicked breast carcinoma, and despite chemotherapy, the fibromatosis rapidly enlarged and was locally invasive requiring wide surgical excision. Unlike previously reported imaging findings, magnetic resonance imaging revealed an oval circumscribed mass with fringe-like internal architecture. We provide a review of the literature and discuss the imaging features of implant-associated fibromatosis of the breast.

Ormond's disease or secondary retroperitoneal fibrosis? An overview of retroperitoneal fibrosis

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Heckmann, M.; Uder, M.; Kuefner, M.A.; Heinrich, M.C. [Universitaetsklinikum Erlangen (Germany). Radiologisches Inst.

2009-04-15

Retroperitoneal fibrosis represents a rare inflammatory disease. About two thirds of all cases seem to be idiopathic (= Ormond's disease). The remaining one third is secondary and may be ascribed to infections, trauma, radiation therapy, malignant diseases, and the use of certain drugs. Up to 15 % of patients have additional fibrotic processes outside the retroperitoneum. The clinical symptoms of retroperitoneal fibrosis are non-specific. In sonography retroperitoneal fibrosis appears as a retroperitoneal hypoechoic mass which can involve the ureters and thus cause hydronephrosis. Intravenous urography and MR urography can demonstrate the typical triad of medial deviation and extrinsic compression of the ureters and hydronephrosis. CT and MRI are the modalities of choice for the diagnosis and follow-up of this disease. The lesion typically begins at the level of the fourth or fifth lumbar vertebra and appears as a plaque, encasing the aorta and the inferior vena cava and often enveloping and medially displacing the ureters. In unenhanced CT, retroperitoneal fibrosis appears as a mass that is isodense with muscle. When using MRI, the mass is hypointense in T1-weighted images and of variable intensity in T2-weighted images according to its stage: it may be hyperintense in early stages, while the tissue may have a low signal in late stages. After the administration of contrast media, enhancement is greatest in the early inflammatory phase and minimal in the late fibrotic phase. Dynamic gadolinium enhancement can be useful for assessing disease activity, monitoring response to treatment, and detecting relapse. To differentiate retroperitoneal masses, diffusion-weighted MRI may provide useful information. (orig.)

A large and aggressive fibromatosis in the axilla: a rare case report and review of the literature

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Duan M

2018-05-01

Full Text Available Mingyue Duan,1 Hua Xing,1 Keren Wang,1 Chunbo Niu,2 Chengwei Jiang,2 Lijuan Zhang,1 Shereen Ezzat,3 Le Zhang1 1Department of Breast Surgery, China-Japan Union Hospital, Jilin University, Changchun, Jilin, People’s Republic of China; 2Department of Pathology, China-Japan Union Hospital, Jilin University, Changchun, Jilin, People’s Republic of China; 3Ontario Cancer Institute and The Endocrine Oncology Site Group, Princess Margaret Hospital, University Health Network, Toronto, ON, Canada Abstract: Aggressive fibromatosis (AF is a rare benign tumor, which occurs in the deep part of bone and muscle fibrous tissue. Clinical and pathological features can be challenging for definitive diagnosis. Here, we report a rare case of a large AF in the axilla. Interestingly, 18 F-fluorodeoxyglucose-positron emission tomography/computed tomography showed significant increase in standard uptake value. Surgical resection yielded a spindle cell tumor likely of fibromatosis origin which was positive for β-catenin expression. Keywords: aggressive fibromatosis, desmoid-type fibromatosis, axilla, 18 F-fluorodeoxyglucose, PET/CT, β-catenin

Aggressive laryngeal fibromatosis: A case report and brief review

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Enam Murshed Khan

2018-01-01

Full Text Available We describe a rare case of aggressive fibromatosis of the larynx occurring in a 72-year-old man. The lesion manifested with complaints of dyspnea and stridor. A computerized tomographic scan of the neck revealed irregular polypoidal growth invading right vocal cord, crossing midline. A malignant tumor was suspected. Although several laryngoscopy-driven biopsies were negative for malignancy, total laryngectomy was done since the lesion was not deemed amenable to conservative therapy. Tissue sections featured a moderately cellular lesion composed of spindle cells with bland, elongated nuclei, enmeshed in a variably collagenized ground substance. The spindle cells were immunopositive for vimentin and negative for cytokeratins, PGP-9.5, smooth muscle antigen, CD68, desmin, and S-100 protein and Ki-67 of 4%. No further therapy was administered. Based on the available literature, our data confirm that aggressive laryngeal fibromatosis in adult patients is a locally infiltrating disease. Total laryngectomy with clear margins is needed as to avoid the high risk of local recurrence.

Gigantic retroperitoneal leiomyosarcoma - case report

International Nuclear Information System (INIS)

Snarska, J.; Hady, H. R.; Kaminski, F.; Szajda, S. D.; Werel, D.; Zimnoch, L.; Siemiatkowski, A.

2007-01-01

Retroperitoneal leiomyosarcomas are very rare malignant neoplasms. They are built up of smooth muscle cells. They can be found beyond the retroperitoneal space in the uterus, the stomach, the intestines, the blood vessel walls and the skin. This type of tumour grows slowly and gives no characteristic clinical symptoms. This results in late diagnosis, when they grow to a huge size. Retroperitoneal leiomyosarcomas are most frequently described in the literature in the fifth or sixth decade of life. There are no biochemical markers which could suggest the development of leiomyosarcoma. The basic diagnostic examination includes: ultrasound and computer tomography of the abdomen. The fundamental treatment of retroperitoneal leiomyosarcomas consists in aggressive surgical treatment - complete tumour resection. Large size of the tumour can make it difficult to perform radical surgery. In the case presented in this report, our team managed to remove a retroperitoneal leiomyosarcoma completely despite its huge mass and size (300 x 200 mm). Data from the literature indicate that a complete resection of the tumour is the most significant prognostic factor in the case of patients with retroperitoneal leiomyosarcoma. The efficacy of radiotherapy and chemotherapy has not been proved. The other unfavourable prognostic factor in the course of sarcomas is the age of the patient, below 50 years old. The patient presented in the report is a 31-year-old woman, which is associated with a worse prognosis. According to some authors, the size of the tumour is not significant for the fast recurrence of the disease, whereas others state that it is. The case was presented because of such a huge leiomyosarcoma being rarely found in the retroperitoneal space, the age of the patient and the asymptomatic course of the disease. (authors)

Child gluteal aggressive fibromatosis: a correlative study of CT findings and pathology

International Nuclear Information System (INIS)

Fan Miao; Li Ziping; Meng Quanfei; Guo Yan; Ye Bingbing; Xiao Gang

2005-01-01

Objective: To evaluate CT imaging in the diagnosis of child gluteal aggressive fibromatosis. Methods: CT manifestations of child gluteal aggressive fibromatosis were retrospectively analyzed. In total 7 males and 1 female, 2 to 11 years old, were enrolled in study. All cases had been confirmed by surgery and pathology. CT findings were correlatively studied with pathology. Results: Lesions located on the left side were noted in 7 cases, and a lesion located on right side was seen in the rest 1 cam The lesions were elliptical or lobulated on CT images. Three tumors originated from solitary muscle and multiple muscles were involved in other 5 cases. Tumors were well demarcated. Invasion to the adjacent structure was shown in 7 cases. All tumors were homogeneous in density in non-enhanced scan. Compared to the muscles in the same section, 5 tumors were iso -density and 3 tumors were hypo-density. Inside the lesions no hemorrhage, necrosis, cystic degeneration and calcification was revealed. After contrast medium was administrated, iso-dense and homogeneous enhancement as the adjacent muscles was seen in 1 tumor and apparent enhancement were demonstrated in 7 tumors. Seven tumors tended to grow along the longitudinal axis of muscles and infiltrated into fascial space. Atrophy resulting from compression was shown in the adjacent muscles in 6 cases. The major clinical manifestation was limp. Gluteal aggressive fibromatosis was confirmed by pathology in all cases. Conclusion: There are characteristics of child gluteal aggressive fibromatosis in age of onset, gender of the patients, site of the lesion and CT findings as well. CT manifestations were consistent with pathology. CT imaging is helpful in initial diagnosis and differential diagnosis, as well as in assessing the expansion of the tumor and involvement of the adjacent structures. (authors)

Desmoid type fibromatosis in the facet joint of lumbar spine: Case report and review of literature

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Kim, So Jung; Ha, Doo Hoe; Lee, Sang Min; Kang, Hae Youn [CHA Bundang Medical Center, CHA University, Seongnam (Korea, Republic of)

2013-10-15

Desmoid type fibromatosis is a benign fibroblastic tumor arising from the fascia or musculoaponeurosis. It may occur in various locations, but most commonly in the shoulder girdle and neck; to our knowledge, there has been no reported case originating from a facet joint of the spine. We report CT and MR imaging findings of a desmoid type fibromatosis, involving the facet joint of the L3-4 spine with bone involvement.

An Algorithmic Approach to the Management of Infantile Digital Fibromatosis: Review of Literature and a Case Report.

Science.gov (United States)

Eypper, Elizabeth H; Lee, Johnson C; Tarasen, Ashley J; Weinberg, Maxene H; Adetayo, Oluwaseun A

2018-01-01

Objective: Infantile digital fibromatosis is a rare benign childhood tumor, infrequently cited in the literature. Hallmarks include nodular growths exclusive to fingers and toes and the presence of eosinophilic cytoplasmic inclusions on histology. This article aims to exemplify diagnoses of infantile digital fibromatosis and possible treatment options. Methods: A computerized English literature search was performed in the PubMed/MEDLINE database using MeSH headings "infantile," "juvenile," "digital," and "fibromatosis." Twenty electronic publications were selected and their clinical and histological data recorded and used to compile a treatment algorithm. Results: A 9-month-old male child was referred for a persistent, symptomatic nodule on the third left toe. A direct excision with Brunner-type incisions was performed under general anesthesia. The procedure was successful without complications. The patient has no recurrence at 2 years postsurgery and continues to be followed. Histological examination revealed a proliferation of bland, uniformly plump spindle cells with elongated nuclei and small central nucleoli without paranuclear inclusions consistent with fibromatosis. Conclusions: Asymptomatic nodules should be observed for spontaneous regression or treated with nonsurgical techniques such as chemotherapeutic or steroid injection. Surgical removal should be reserved for cases with structural or functional compromise.

Radiotherapy in fascial fibromatosis: a case series, literature review and considerations for treatment of early-stage disease

International Nuclear Information System (INIS)

Grenfell, Solveig; Borg, Martin

2014-01-01

Palmar and plantar fascial fibromatoses are benign hyperproliferative disorders of the deep fascia of the palm and sole. This study seeks to examine the role of radiotherapy in the management of fascial fibromatosis. Six consecutive cases of early-stage fascial fibromatosis treated with radiotherapy at the Adelaide Radiotherapy Centre between July 2008 and May 2011 were analysed. The results of the case series were compared with a systematic review of the literature. All six cases regressed or showed a reduction of symptoms following radiotherapy. Treatment was well tolerated with minor toxicities. Median follow-up for the case series was 38.5 months. The systematic review identified seven studies describing the use of radiotherapy as primary treatment for fascial fibromatosis between 1946 and 2013. The literature indicates that radiotherapy can prevent disease progression and improve symptoms for early-stage disease, with low likelihood of significant toxicities. Early results from our case series are consistent with the literature, showing that radiotherapy can provide an effective management option for patients with early-stage fascial fibromatosis, and justify consideration of radiotherapy as a primary treatment for early-stage disease.

Two distinct gamma-2 herpesviruses in African green monkeys: a second gamma-2 herpesvirus lineage among old world primates?

NARCIS (Netherlands)

Greensill, J.; Sheldon, J. A.; Renwick, N. M.; Beer, B. E.; Norley, S.; Goudsmit, J.; Schulz, T. F.

2000-01-01

Primate gamma-2 herpesviruses (rhadinoviruses) have so far been found in humans (Kaposi's sarcoma-associated herpesvirus [KSHV], also called human herpesvirus 8), macaques (Macaca spp.) (rhesus rhadinovirus [RRV] and retroperitoneal fibromatosis herpesvirus [RFHV]), squirrel monkeys (Saimiri

Fibromatosis of the breast mimicking an abscess: case report of unusual sonographic features.

Science.gov (United States)

Lee, So Min; Lee, Ji Young; Lee, Byung Hoon; Kim, Su Young; Joo, Mee; Kim, Jae Il

2015-01-01

Fibromatosis of the breast, also known as a desmoid tumor, is extremely rare and most often appears as an aggressive lesion mimicking breast carcinoma. It lacks metastatic potential but can grow aggressively in a localized area. Ultrasonography often shows an irregular spiculated hypoechoic mass with posterior acoustic shadowing. We discuss a case of breast fibromatosis that presented as a painful palpable breast mass in a 32-year-old woman and mimicked an abscess in the sonogram. We found that this lesion displayed atypical sonographic features such as a heterogeneous echoic mass with an internal anechoic area. Copyright © 2015 Elsevier Inc. All rights reserved.

Pazopanib, a promising option for the treatment of aggressive fibromatosis

NARCIS (Netherlands)

Szucs, Z.; Messiou, C.; Wong, H.H.; Hatcher, H.; Miah, A.; Zaidi, S.; Graaf, W.T.A. van der; Judson, I.; Jones, R.L.; Benson, C.

2017-01-01

Desmoid tumour/aggressive fibromatosis (DT/AF) is a rare soft-tissue neoplasm that is locally aggressive but does not metastasize. There is no standard systemic treatment for symptomatic patients, although a number of agents are used. Tyrosine kinase inhibitors have recently been reported to show

Liposarcoma retroperitoneal gigante. Reporte de caso (Giant retroperitoneal liposarcoma. Case report

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Eduardo Reyna-Villasmil

2015-01-01

Full Text Available Soft tissue sarcomas represent less than 1% of all human neoplasms. One-third of malignant tumors that arise in the retroperitoneum are sarcomas and liposarcoma is the most common retroperitoneal sarcoma and is known to grow to giant sizes, slow progress and few late symptoms. We report the case of a 40 year old woman with a giant retroperitoneal liposarcoma. A laparotomy was performed and a multilobulated tumor of 20 centimeters of diameter arising from retroperitoneum. The histological features were suggestive of pleomorphic liposarcoma weighing 8.5 Kilograms

Does negative retroperitoneal CT in adolescents with paratesticular rhabdomyosarcoma preclude the need of retroperitoneal lymph node dissection?

International Nuclear Information System (INIS)

Damazio, Eulalio; Caran, Eliana; Ortiz, Valdemar; Macedo Junior, Antonio

2011-01-01

We report on a 16-year-old male with paratesticular rhabdomyosarcoma who underwent retroperitoneal lymph node dissection due to a stage I tumor (normal retroperitoneal computed tomography). The surgical finding was three enlarged nodes, positive for metastatic disease. Patient was referred to adjuvant chemotherapy. This case suggests that the Intergroup Rhabdomyosarcoma Study Group IV protocol is subject to questions regarding adolescents with paratesticular rhabdomyosarcoma, and that negative retroperitoneal CT does not preclude the need of lymph node dissection. (author)

Ultrasound and MR imaging of fibromatosis colli (sternomastoid tumor of infancy)

International Nuclear Information System (INIS)

Ablin, D.S.; Jain, K.; Howell, L.; West, D.C.

1998-01-01

The sonographic and CT findings of fibromatosis colli (sternomastoid tumor of infancy) have been described, but the MRI appearance has been reported in only one case in which the mass resolved over time. This case describes the detailed MRI findings in a biopsy-proven case of fibromatosis colli; the signal intensity of the mass on T2-weighted images was slightly less than on gradient-recalled T1-weighted images, consistent with the presence of some fibrous tissue within the muscle mass. The involved portion of the muscle was better defined on MRI than sonography. MRI was helpful in demonstrating the signal characteristics of the mass; localizing the mass to within the sternocleidomastoid muscle; and demonstrating clear surrounding fascial planes with lack of associated lymphadenopathy, airway compression, vascular encasement, bone involvement or intracranial/intraspinal extension associated with other neck masses. (orig.)

Fibromatosis-like carcinoma-an unusual phenotype of a metaplastic breast tumor associated with a micropapilloma

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Badwe Rajan A

2007-02-01

Full Text Available Abstract Background Fibromatosis-like metaplastic carcinoma is a newly described metaplastic breast tumor, literature on which is still evolving. Case presentation A 77-year-old lady presented with a 2 × 2 cm mass with irregular margins in the upper and outer quadrant of left breast. Fine needle aspiration cytology (FNAC from the lump was inconclusive. A lumpectomy was performed and sent for frozen section, which revealed presence of spindle cells showing mild atypia in a sclerotic stroma. The tumor cells revealed prominent infiltration into the adjacent fat. A differential diagnosis of a low-grade sarcoma vs. a metaplastic carcinoma, favoring the former, was offered. Final histology sections revealed an infiltrating tumor with predominant spindle cells in a collagenous background, simulating a fibromatosis. Adjacent to the tumor were foci of benign ductal hyperplasia and a micropapilloma. Immunohistochemistry (IHC showed diffuse co-expression of epithelial markers i.e. cytokeratins (CK, HMWCK, CK7 and EMA along with a mesenchymal marker i.e. vimentin in the tumor cells. Myoepithelial markers (SMA and p63 showed focal positivity. A diagnosis of a low-grade fibromatosis-like carcinoma breast associated with a micropapilloma was formed. Conclusion Fibromatosis-like carcinoma is a rare form of a metaplastic breast tumor. This diagnosis requires an index of suspicion while dealing with spindle cell breast tumors. The importance of making this diagnosis to facilitate an intra operative surgical planning is marred by diagnostic difficulties. In such cases, IHC is imperative in forming an objective diagnosis.

CT characteristics of primary retroperitoneal neoplasms in children

International Nuclear Information System (INIS)

Xu Yufeng; Wang Jichen; Peng Yun; Zeng Jinjin

2010-01-01

Primary retroperitoneal neoplasms are uncommon in children. Retroperitoneal neoplasms are either mesodermal, neurogenic, germ cell ectodermal or lymphatic in origin. In general, primary retroperitoneal neoplasms in children have different spectrum and prevalence compared to those in adults. Neuroblastoma, rhabdomyosarcoma, benign teratoma and lymphoma are the common retroperitoneal neoplasms. In this review, the clinical and CT futures of common retroperitoneal neoplasms in children are described. Coarse, amorphous, and mottled calcification are very common in neuroblastoma. Paraganglioma tends to show marked and early enhancement and may present with clinical symptoms associated with the excess catecholamine. Sarcomas are often very large and have heterogeneous appearance. Imaging cannot be reliably used to identify the type of retroperitoneal sarcomas due to overlapped radiographic features. In children, lipoblastoma is the most common lipomatous tumor in the retroperitoneum. The percentage of visible fat in tumor varies depending on the cellular composition of the lesion. The CT characteristics of teratoma are quite variable, which may be cystic, solid, on a combination of both. Typically teratoma appears as a large complex mass containing fluid, fat, fat-fluid level, and calcifications. Lymphoma is often homogeneous on both enhanced and unenhanced CT scans. Necrosis and calcification are rare on CT. In conclusion, making a final histological diagnosis of retroperitoneal tumor base on CT features is not often possible; however, CT can help to develop a differential diagnosis and determine the size and extent of the retroperitoneal neoplasms.

Schwannoma retroperitoneal maligno Malign retroperitoneal schwannoma

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Rafael Pinilla González

2009-12-01

Full Text Available Los tumores del retroperitoneo son poco frecuentes y se clasifican según el tejido del que se originan. Se presenta el caso de una paciente con dolor en el hipocondrio derecho y tumor en esta zona, pérdida de peso y molestia dolorosa en la cara anterolateral del muslo derecho. En el examen físico se halló palidez cutáneo-mucosa y tumoración indolora en el hipocondrio y flanco derecho. El ultrasonido abdominal mostró una masa homogénea de 14,11 cm y la tomografía computarizada de abdomen permitió observar un tumor retroperitoneal derecho que rechazaba el riñón. El urograma excretor mostró rechazamiento anteromedial del riñón derecho. Se extirpó un tumor encapsulado con pocas adherencias peritumorales. Mediante estudio histológico se confirmó un tumor de células fusiformes con hipercromatismo y pleomorfismo nuclear, numerosas mitosis y áreas de necrosis y el diagnóstico de tumor maligno de la vaina de un nervio periférico.The retroperitoneal tumors are infrequent and are classified according to the original tissue. This is a case presentation of a patient presenting with pain in right hypochondrium and a tumor in this zone, weight loss and painful discomfort in the anterolateral face of right thigh. In physical examination we found cutaneous-mucous paleness and painless tumor in hypochondrium and right flank. Abdominal ultrasound (US showed a homogenous mass of 14,11 cm and abdominal computed tomography allows to see a right retroperitoneal tumor rejecting the kidney. Excretory urogram showed a anteromedial rejection of right kidney. An encapsulated tumor with a few peritumoral adherences was removed. By histological study it was possible to confirm a fusiform cells tumor with hyperchromatism and nuclear pleomorphism, numerous mitosis and areas of necrosis and in the diagnosis of malign tumor of the sheath of a peripheral nerve.

Slow growing desmoid-type fibromatosis of the breast: A case report

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Park, Ah Reum; Kim, Ji Young; Kim, Hyun Jung; KIm, Jae Hyung; Jeong, Myeong Ja; Kim, Soung Hee; Kim, Soo Hyun; Kang, Mi Jin; Lee, Ji Hae; Bae, Kyung Eun [Sanggye Paik Hospital, Inje University College of Medicine, Seoul (Korea, Republic of)

2017-04-15

Fibromatosis or desmoid tumor of the breast is a rare benign entity that has no metastatic potential but has significant risk of local recurrence. Its association with previous surgical or accidental trauma and Gardner's syndrome has been reported. Awareness of this lesion is important as the diagnosis is often confused with breast carcinoma. We report a case of a 44-year-old woman who presented with a palpable mass in her left breast, close to the axilla since a few months ago. She had undergone excisional biopsy for her left breast mass 15 months ago, and the diagnosis was confirmed as intraductal papilloma with atypical ductal hyperplasia. Subsequent ultrasound and core needle biopsy revealed stromal fibrosis. After 9 months, the mass showed an increase in its size and the anteroposterior to width ratio on ultrasonography compared to the previous examination, and final excisional biopsy confirmed the diagnosis of desmoid-type fibromatosis.

Radiotherapy in the management of aggressive fibromatosis

International Nuclear Information System (INIS)

Atahan, I.L.; Akyol, F.; Zorlu, F.; Guerkaynak, M.

1989-01-01

Four case reports are summarised concerning the management of aggressive fibromatosis in children and adolescents up to the age of 15. It was concluded that radiotherapy should be reserved for recurrences or inoperable cases. A dose of 5000-6000 cGy in 25-30 fractions depending on age of patient, site, and size of tumour is necessary, since most surgical recurrences appear in 12 months, all cases with positive surgical margins should receive doses in the range 4000-4500 cGy for microscopic disease. Radiotherapy-chemotherapy combinations can also be used. (UK)

CT diagnosis of retroperitoneal gigantic liposarcoma

International Nuclear Information System (INIS)

Fang Wei; Zheng Zhaohua; Liao Zuyuan; Hu Yinsong

2009-01-01

Objective: To analyze CT manifestation of retroperitoneal gigantic liposaxcoma and to improve the image understanding. Methods: Five cases of retroperitoneal gigantic liposarcoma confirmed by surgery and pathology in our hospital were collected. Plain and enhanced CT scan were performed. Results: Of five cases, one was substantive, two was pseudocyst and two was mixed tumor. Several patterns of enhancement such as strip, floccule, irregular patchy or nodular enhancement were revealed inside the lesions on enhanced CT scan. And strip-form of high density enhancement was a typical type. Conclusion: CT examination could determine the tumor's location, size and density, together with the relationship to adjacent organizations CT scan is an important method in diagnosing retroperitoneal gigantic liposarcoma. (authors)

Endoscopic findings following retroperitoneal pancreas transplantation.

Science.gov (United States)

Pinchuk, Alexey V; Dmitriev, Ilya V; Shmarina, Nonna V; Teterin, Yury S; Balkarov, Aslan G; Storozhev, Roman V; Anisimov, Yuri A; Gasanov, Ali M

2017-07-01

An evaluation of the efficacy of endoscopic methods for the diagnosis and correction of surgical and immunological complications after retroperitoneal pancreas transplantation. From October 2011 to March 2015, 27 patients underwent simultaneous retroperitoneal pancreas-kidney transplantation (SPKT). Diagnostic oesophagogastroduodenoscopy (EGD) with protocol biopsy of the donor and recipient duodenal mucosa and endoscopic retrograde pancreatography (ERP) were performed to detect possible complications. Endoscopic stenting of the main pancreatic duct with plastic stents and three-stage endoscopic hemostasis were conducted to correct the identified complications. Endoscopic methods showed high efficiency in the timely diagnosis and adequate correction of complications after retroperitoneal pancreas transplantation. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Giant Retroperitoneal Lipoma in an Infant

African Journals Online (AJOL)

2010-06-29

Jun 29, 2010 ... We are reporting the case of a six-month-old child who presented with a giant retroperitoneal lipoma that was successfully managed by complete ... Retroperitoneal lipoma is an unusual entity that is most often found in adults between 40 and 60 years of age and rarely occurs in the first decade of life.

Gingival Fibromatosis with Chronic Periodontitis – A Rare Case Report

OpenAIRE

Sanadi Rizwan M

2009-01-01

Gingival fibromatosis is frequently an isolatedcondition of little consequence apart from a cosmeticproblem and occasional associations with uncommonsyndromes. This case report of a 38 year old femalepatient describes the gingival enlargement associatedwith chronic periodontitis. The enlargement extendedbeyond the middle thirds of the clinical crowns of theteeth. It was associated with generalized mobility,pocket formation and bone loss. The patient alsocomplained of bleeding gums and difficu...

Delayed hydronephrosis due to retroperitoneal hematoma after a seatbelt injury

Science.gov (United States)

Yumoto, Tetsuya; Kondo, Yoshitaka; Kumon, Kento; Masaoka, Yoshihisa; Hiraki, Takao; Yamada, Taihei; Naito, Hiromichi; Nakao, Atsunori

2018-01-01

Abstract Rationale: Hydronephrosis caused by retroperitoneal hematoma after a seatbelt injury is a unique clinical entity. Patient concerns: A 21-year-old man, who had been wearing a seatbelt, was brought to our hospital after a motor vehicle collision, complaining of abdominal pain. Computed tomography (CT) revealed retroperitoneal hematoma in the upper pelvic region. Since he was hemodynamically stable throughout admission, he was managed conservatively. Seventeen days after initial discharge, the patient revisited our emergency department due to right back pain. Diagnoses: CT scans indicated retroperitoneal hematoma growth resulting in hydronephrosis of the right kidney. Interventions: Laparoscopic drainage of the retroperitoneal hematoma was successfully performed. Outcomes: His symptoms resolved after the surgery. Follow-up CT scans three months later demonstrated complete resolution of the hydronephrosis and retroperitoneal hematoma. Lessons: Our case highlights a patient with delayed hydronephrosis because of retroperitoneal hematoma expansion after a seatbelt injury. PMID:29879068

Diseases of the retroperitoneal space in the dog and cat

International Nuclear Information System (INIS)

Roush, J.K.; Bjorling, D.E.; Lord, P.

1990-01-01

The retroperitoneal space (RPS) is an anatomical area bounded dorsally by the sublumbar musculature and ventrally by the peritoneal surface of the abdomen. The RPS communicates with the pelvic space and mediastinum and is subject to primary diseases of the RPS connective tissue and to extension of disease from organs lying within or adjacent to it. Primary diseases include retroperitonitis, pneumoretroperitoneum, non-neoplastic retroperitoneal space-occupying lesions, and primary neoplasms of the RPS. Primary diseases of kidneys, ureters, adrenal glands or retroperitoneal lymph nodes may extend into the RPS, and the RPS may be the site of metastatic neoplastic disease. Clinical signs suggestive of retroperitoneal disease include lumbar pain, pyrexia, lethargy, and signs referable to organs within the RPS

Malign retroperitoneal schwannoma

International Nuclear Information System (INIS)

Pinilla Gonzalez, Rafael; Hadi Al-Bahlooli, Saeed; Lopez Lazo, Sarah; Quintana Diaz, Juan Carlos; Gonzales Rivera, Armando

2009-01-01

The retroperitoneal tumors are infrequent and are classified according to the original tissue. This is a case presentation of a patient presenting with pain in right hypochondrium and a tumor in this zone, weight loss and painful discomfort in the anterolateral face of right thigh. In physical examination we found cutaneousmucous paleness and painless tumor in hypochondrium and right flank. Abdominal ultrasound (US) showed a homogenous mass of 14,11 cm and abdominal computed tomography allows to see a right retroperitoneal tumor rejecting the kidney. Excretory urogram showed a anteromedial rejection of right kidney. An encapsulated tumor with a few peritumoral adherences was removed. By histological study it was possible to confirm a fusiform cells tumor with hyperchromatism and nuclear pleomorphism, numerous mitosis and areas of necrosis and in the diagnosis of malign tumor of the sheath of a peripheral nerve.(author)

Retroperitoneal and lateral pelvic lymphadenectomy mapped by lymphoscintigraphy for rectal adenocarcinoma staging

International Nuclear Information System (INIS)

Quadros, C.A.; Araujo, I.; Lopes, A.

2010-01-01

The good prognosis of retroperitoneal and lateral pelvic lymphadenectomy has raised the question of whether total mesorectal excision is suitable for adequate staging of rectal adenocarcinoma patients. The aims of this study were to determine the accuracy of dye and probe detection of metastatic retroperitoneal and/or lateral pelvic nodes and to define the upstaging impact of retroperitoneal and lateral pelvic lymphadenectomy in rectal adenocarcinoma patients. Ninety-seven rectal adenocarcinoma patients were submitted to total mesorectal excision and retroperitoneal and lateral pelvic lymphadenectomy. Lymphoscintigraphy using technetium-99 m-phytate and patent blue was performed to detect blue and/or radioactive retroperitoneal and/or lateral pelvic nodes which were examined histopathologically and immunohistochemically with a step-sectioning technique. Mesorectal mean node count was 11.5 and retroperitoneal and/or lateral pelvic node was 11.7. Retroperitoneal and lateral pelvic lymphadenectomy identified metastases in 17.5%, upstaging 8.2%. Variables related to metastatic retroperitoneal and/or lateral pelvic nodes were the following: Stage III in total mesorectal excision specimens (P<0.04), pT3/pT4 tumors (P=0.047), high levels of carcinoembryonic antigen (P=0.014) and large tumors (P=0.03). Marker migration to retroperitoneal and/or lateral pelvic nodes occurred in 37.1%, upstaging 11.1%. The markers' accuracy in the detection of metastatic retroperitoneal and/or lateral pelvic nodes was 100%. Retroperitoneal and lateral pelvic lymphadenectomy detected an important rate of metastatic retroperitoneal and/or lateral pelvic nodes (RLPN), resulting in upstaging. When markers migrated, they were able to detect RLPN metastases. The use of markers should be improved in the identification of RLPN metastases for selective indication of retroperitoneal and lateral pelvic lymphadenectomy. (author)

Unusual Presentation Of Idiopathic Retroperitoneal Fibrosis: Case ...

African Journals Online (AJOL)

Idiopathic retroperitoneal fibrosis (IRF) is an uncommon entity described as progressive proliferation of connective tissues leading to a fibrous plaque-like lesions that encases the aorta and inferior vena cava inferior to the level of the renal arteries. Mass forming retroperitoneal fibrosis is rare. We present a rare case of a ...

Aggressive fibromatosis of the neck in a patient with Gardner's syndrome

International Nuclear Information System (INIS)

Rai, A.T.; Nguyen, T.P.; Hogg, J.P.; Gabriele, F.J.

2001-01-01

We report a patient with Gardner's syndrome who, in addition to a total colectomy, had multiple excisions of desmoid tumors in both thighs. He presented with left-sided neck swelling and pain. MRI was highly suggestive of desmoid tumors in multiple neck muscles. To our knowledge this is the first description of diffuse fibromatosis of the neck in association with Gardner's syndrome. (orig.)

Idiopathic gingival fibromatosis associated with progressive hearing loss: A nonfamilial variant of Jones syndrome

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Bagavad Gita

2014-01-01

Full Text Available Gingival fibromatosis is characterized by gingival tissue overgrowth of a firm and fibrotic nature. The growth is slow and progressive and is drug-induced, idiopathic, or hereditary in etiology. It occurs isolated or frequently as a component of various syndromes. Our patient presented with the complaint of gingival enlargement associated with progressive deafness, characteristic of Jones syndrome. This case report is important and unique since it is the first known one to have a Jones syndrome-like presentation without a family history. A male patient aged 14 years reported with the chief complaint of swelling of gums and progressive hearing loss in both ears for the past one year. There was no family history or history of drug intake. Enlargement was generalized, fibrotic and bulbous, involving the free and attached gingiva, extending up to the middle 1/3 rd of the crown. Investigations such as pure tone audiogram, impedance audiometry, and Tone decay test concluded that there was severe right and moderate left sensorineural hearing loss. The case was diagnosed to be idiopathic, generalized gingival fibromatosis with progressive hearing loss. The gingival overgrowth was managed by gingivectomy and periodic review. The patient was advised to use high occlusion computer generated hearing aids for his deafness as it was not treatable by medicines or surgery. This unique case report once again emphasizes the heterogeneity of gingival fibromatosis, which can present in an atypical manner.

Unusual Cause of Acute Abdomen—Ruptured Retroperitoneal Paraganglioma

OpenAIRE

Kwok-Kay Yau; Wing-Tai Siu; Michael Ka-Wah Li

2008-01-01

Ruptured retroperitoneal paraganglioma is a rare cause of acute abdomen. Its clinical presentation and laparoscopic features have seldom been reported in the literature. Herein, we report a case of ruptured retroperitoneal paraganglioma that presented as acute abdomen, and its subsequent management.

Atypical retroperitoneal extension of iliopsoas bursitis

International Nuclear Information System (INIS)

Coulier, B.; Cloots, V.

2003-01-01

We report two rare cases of iliopsoas bursitis extending into the retroperitoneal space. The first lesion contained much gas, mimicking a retroperitoneal abscess, and the second was responsible for atypical inguinal pain. The diagnosis was made by contrast-enhanced CT in both cases and arthrography in the first case. Iliopsoas bursitis in these two patients, it is hypothesized, extended into the retroperitoneum, at least in part, by way of intraneural or perineural structures. (orig.)

Atypical retroperitoneal extension of iliopsoas bursitis

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Coulier, B.; Cloots, V. [Department of Diagnostic Imaging, Cliniques St. Luc, Rue St Luc 8, 5004, Bouge, Namur (Belgium)

2003-05-01

We report two rare cases of iliopsoas bursitis extending into the retroperitoneal space. The first lesion contained much gas, mimicking a retroperitoneal abscess, and the second was responsible for atypical inguinal pain. The diagnosis was made by contrast-enhanced CT in both cases and arthrography in the first case. Iliopsoas bursitis in these two patients, it is hypothesized, extended into the retroperitoneum, at least in part, by way of intraneural or perineural structures. (orig.)

Gingival fibromatosis with hypertrichosis syndrome: Case series of rare syndrome

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Preetha Balaji

2017-01-01

Full Text Available Gingival fibromatosis with hypertrichosis syndrome is an extremely rare genetic condition characterized by profound overgrowth of hair and gums, as well as other variable features. Gingival fibromatosis is characterized by a large increase in the gingival dimension which extends above the dental crowns, covering them partially or completely. They were found to have a genetic origin, may also occur in isolation or be part of a syndrome, or acquired origin, due to specific drugs administered systemically. Congenital generalized hypertrichosis is a heterogeneous group of diseases with continuing excessive growth of terminal hair without androgenic stimulation. It has informally been called werewolf syndrome because the appearance is similar to that of a werewolf. Various syndromes have been associated with these features such as epilepsy, mental retardation, cardiomegaly, or osteochondrodysplasia. As so far very few cases have been reported in literature, we are reporting a series of three cases with management of the same. The excess gingival tissues, in these cases, were removed by conventional gingivectomy under general anesthesia. The postoperative result was uneventful and the patient's appearance improved significantly. Good esthetic result was achieved to allow patient to practice oral hygiene measures. Though this is not a serious condition clinically, psychosocial trauma cannot be neglected owing to the cosmetic disfigurement it produces.

Unusual Cause of Acute Abdomen—Ruptured Retroperitoneal Paraganglioma

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Kwok-Kay Yau

2008-01-01

Full Text Available Ruptured retroperitoneal paraganglioma is a rare cause of acute abdomen. Its clinical presentation and laparoscopic features have seldom been reported in the literature. Herein, we report a case of ruptured retroperitoneal paraganglioma that presented as acute abdomen, and its subsequent management.

Familial gingival fibromatosis: A rare case report

Directory of Open Access Journals (Sweden)

Shweta Sharma

2012-01-01

Full Text Available Hereditary gingival fibromatosis is a rare condition that can occur as an isolated disease or as part of a syndrome or chromosomal abnormality. In severe cases, the gingival enlargement may cover the crowns of teeth and cause severe functional and aesthetic concerns. Here, we present a case of an 8-year-old girl with severe enlargement of gums in maxilla and mandible. Both deciduous and permanent teeth were not erupted in the oral cavity at all. Mutation in the Son-of-Sevenless (SOS-1 gene has been associated with the disease. The diagnosis was made based on clinical examination and family history. Surgical removal of the hyperplastic tissue was performed under general anesthesia.

Primary retroperitoneal soft tissue sarcoma: Imaging appearances, pitfalls and diagnostic algorithm.

Science.gov (United States)

Messiou, C; Moskovic, E; Vanel, D; Morosi, C; Benchimol, R; Strauss, D; Miah, A; Douis, H; van Houdt, W; Bonvalot, S

2017-07-01

Although retroperitoneal sarcomas are rare tumours, they can be encountered by a wide variety of clinicians as they can be incidental findings on imaging or present with non specific symptoms and signs. Surgical resection can offer hope of cure and patient outcomes are improved when patients are managed in high-volume specialist centers. Failure to recognize retroperitoneal sarcomas on imaging can lead to inappropriate management in inexperienced centers. Therefore it is critical that a diagnosis of retroperitoneal sarcoma should be considered in the differential diagnosis of a retroperitoneal mass with prompt referral to a soft tissue sarcoma unit. In particular, the most common retroperitoneal sarcoma subtypes, liposarcoma and leiomyosarcoma, have characteristic imaging appearances which are discussed. This review therefore aims to set the context and guide clinicians through a diagnostic pathway for retroperitoneal masses in adults which arise extrinsic to the solid abdominal viscera. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Enhancement characteristics of retroperitoneal lymphomatous lymph nodes

International Nuclear Information System (INIS)

Hagtvedt, Trond; Smith, Hans-Joergen; Kolbenstvedt, Alf; Aaloekken, Trond Mogens; Graff, Bjoern Anton; Holte, Harald

2013-01-01

Background: Previous studies of CT enhancement of lymphomatous lymph nodes (LLN) of the neck and the mediastinum showed that the LLN had lower enhancement values than normal lymph nodes. Purpose: To elucidate the contrast medium enhancement curves of LLN in the retroperitoneum by comparing the curves of LLN with those of normal lymph nodes, to test whether differences between these curves could be of diagnostic value, and to compare the present enhancement curves of LLN of the retroperitoneum with the curves of LLN of the neck and the mediastinum from previous similar investigations. Material and Methods: Twenty-eight consecutive patients with LLN of the retroperitoneum (three with Hodgkin's lymphoma [HL]) and 21 control patients with sarcomas and thus presumably normal retroperitoneal nodes underwent dynamic CT examinations. The previous, similar investigation of lymph nodes of the neck comprised 28 patients with LLN and the investigation of mediastinal lymph nodes comprised 24 patients with LLN. Results: The enhancement curves of the retroperitoneal LLN had significantly lower attenuation than those of the retroperitoneal control nodes. A combination of peak contrast value and time to peak adjusted to total body weight yielded a diagnostic accuracy which at the best showed a sensitivity of 90.5% with a specificity of 82.6%. The LLN of the retroperitoneum had higher attenuation values than corresponding nodes of the mediastinum but no significant difference was found between LLN of the retroperitoneum and LLN of the neck in previous similar investigations. Conclusion: The comparison of enhancement curves of retroperitoneal LLN with retroperitoneal control nodes showed a marked similarity with and substantiates our previous findings in lymph nodes of the neck and of the mediastinum. The best diagnostic accuracy was achieved by combining the parameters peak contrast value and time to peak and adjusting these values to the body weight. Peak enhancement of the

Retroperitoneal fibrosis with pancreatic involvement – radiological appearance

International Nuclear Information System (INIS)

Zielonko, Joanna; Obołończyk, Łukasz

2011-01-01

Retroperitoneal fibrosis or Ormond’s disease is an uncommon process characterized by fibrous tissue proliferation in the retroperitoneum, usually involving the aorta, inferior vena cava and iliac vessels. Obstructive hydronephrosis is often observed due to ureteral entrapment. This report presents a case of the peripancreatic location of the disease. The role of CT and MRI in establishing diagnosis of retroperitoneal fibrosis in an atypical site is discussed. A 52-year-old woman with Hashimoto’s thyroiditis was admitted to hospital because of pain suggesting renal colic. The patient was subjected to ultrasound, CT, and MRI which did not confirm urolithiasis but revealed pancreatic infiltration. Partial pancreatectomy, left-sided adrenalectomy and splenectomy were performed. Retroperitoneal fibrosis was diagnosed in the histopathological examination. A few weeks after surgery, a complication such as pancreatitis developed. Repeat CT confirmed it and showed right hydronephrosis secondary to ureteral involvement by a mass adjacent to the common iliac artery (defined as a typical manifestation of retroperitoneal fibrosis). Nephrostomy and conservative treatment improved the clinical state of the patient. No progression of the process was observed in the follow-up examinations. Atypical retroperitoneal fibrosis remains a diagnostic challenge. Imaging techniques CT and MRI are useful tools for evaluating the extent of Ormond’s disease. An unusual distribution of the process (e.g. peripancreatic location reported in this study) requires histopathological assessment to establish the final diagnosis

Recurrent thymoma in the retroperitoneal space: a rare case report

Directory of Open Access Journals (Sweden)

Jun Yang

2015-06-01

Full Text Available Thymoma is an epithelial neoplasm of the thymus, which commonly lies in the anterior mediastinum and recurrences of thymoma generally are locally, and retroperitoneal recurrence is considered to be rare. A 46-year old Asian woman with invasive thymoma had undergone thymectomy 10 years ago. Computed tomography demonstrated a wellcircumscribed mass in the left retroperitoneal space. The patient had not any symptom including myasthenia gravis. Because on the anterior mediastinum area shows no sign of tumor recurrence and the mass adjacent to the vertebral body, neurogenic tumor was suspected. Surgical resection was performed using a retroperitoneal approach, which revealed the tumor adhering neighboring diaphragm. The tumor was histologically diagnosed to be type B1 thymoma according to the World Health Organization classification. The retroperitoneal mass was an unusual local recurrence after thymectomy. The patients whose had under invasive thymectomy should be evaluated carefully when finding retroperitoneal mass during follow-up.

Intraoperative Electron Radiotherapy for the Management of Aggressive Fibromatosis

International Nuclear Information System (INIS)

Roeder, Falk; Timke, Carmen; Oertel, Susanne; Hensley, Frank W.; Bischof, Marc; Muenter, Marc W.; Weitz, Juergen; Buchler, Markus W.; Lehner, Burkhard; Debus, Juergen; Krempien, Robert

2010-01-01

Purpose: We analyzed our experience with intraoperative electron radiotherapy (IOERT) followed by moderate doses of external beam radiotherapy (EBRT) after organ-sparing surgery in patients with primary or recurrent aggressive fibromatosis. Methods and Materials: Indication for IOERT and postoperative EBRT as an individual treatment approach to avoid mutilating surgical procedures was seen when complete surgical removal seemed to be unlikely or impossible. A total of 31 lesions in 30 patients were treated by surgery and IOERT with a median dose of 12 Gy. Median age was 31 years (range, 13-59 years). Resection status was close margin in six lesions, microscopically positive in 13, and macroscopically positive in 12. Median tumor size was 9 cm. In all, 25 patients received additional EBRT, with a median dose of 45 Gy (range, 36-54 Gy). Results: After a median follow-up of 32 months (range, 3-139 months), no disease-related deaths occurred. A total of five local recurrences were seen, resulting in actuarial 3-year local control rates of 82% overall and 91% inside the IOERT areas. Trends to improved local control were seen for older age (>31 years) and negative margins, but none of these factors reached significance. Perioperative complications were found in six patients, in particular as wound healing disturbances in five patients and venous thrombosis in one patient. Late toxicity was seen in five patients. Conclusion: Introduction of IOERT into a multimodal treatment approach in patients with aggressive fibromatosis is feasible with low toxicity and yielded good local control rates even in patients with microscopical or gross residual disease.

Retroperitoneal Gastrointestinal Type Schwannoma Presenting as a Renal Mass

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Susan J. Hall

2015-11-01

Full Text Available Retroperitoneal schwannomas are extremely rare, and unreported in Urology. Often thought to be malignant from imaging the diagnosis is often delayed until Histology. We report a case of retroperitoneal schwanoma thought to be a malignant renal mass. Seventy three year old lady presented with abdominal pain. Imaging showed a mass attached to the renal pelvis thus she underwent a radical nephrectomy. Histology reported retroperitoneal schwannoma. Malignant forms are rare however treatment for these is surgical excision. Awareness of the existence of these tumors may help in avoiding unnecessary radical surgeries by opting for biopsy preoperatively.

Surgical anatomy of the retroperitoneal spaces, Part V: Surgical applications and complications.

Science.gov (United States)

Mirilas, Petros; Skandalakis, John E

2010-04-01

Knowledge of the surgical anatomy of the retroperitoneum is crucial for surgery of the retroperitoneal organs. Surgery is essential for treatment of retroperitoneal pathologies. The list of these diseases is extensive and comprises acute and chronic inflammatory processes (abscess, injury, hematoma, idiopathic fibrosis), metastatic neoplasms, and primary neoplasms from fibroadipose tissue, connective tissue, smooth and striated muscle, vascular tissue, somatic and sympathetic nervous tissue, extraadrenal chromaffin tissue, and lymphatic tissue. The retroperitoneum can be approached and explored by several routes, including the transperitoneal route and the extraperitoneal route. The retroperitoneal approach to the iliac fossa is used for ectopic renal transplantation. Safe and reliable primary retroperitoneal access can be performed for laparoscopic exploration. The anatomic complications of retroperitoneal surgery are the complications of the organs located in several compartments of the retroperitoneal space. Complications may arise from incisions to the somatic wall, somatic nerves, blood and lymphatic vessels, lymph nodes, visceral autonomous plexuses, and neighboring splanchna.

Delayed hydronephrosis due to retroperitoneal hematoma after a seatbelt injury: A case report.

Science.gov (United States)

Yumoto, Tetsuya; Kondo, Yoshitaka; Kumon, Kento; Masaoka, Yoshihisa; Hiraki, Takao; Yamada, Taihei; Naito, Hiromichi; Nakao, Atsunori

2018-06-01

Hydronephrosis caused by retroperitoneal hematoma after a seatbelt injury is a unique clinical entity. A 21-year-old man, who had been wearing a seatbelt, was brought to our hospital after a motor vehicle collision, complaining of abdominal pain. Computed tomography (CT) revealed retroperitoneal hematoma in the upper pelvic region. Since he was hemodynamically stable throughout admission, he was managed conservatively. Seventeen days after initial discharge, the patient revisited our emergency department due to right back pain. CT scans indicated retroperitoneal hematoma growth resulting in hydronephrosis of the right kidney. Laparoscopic drainage of the retroperitoneal hematoma was successfully performed. His symptoms resolved after the surgery. Follow-up CT scans three months later demonstrated complete resolution of the hydronephrosis and retroperitoneal hematoma. Our case highlights a patient with delayed hydronephrosis because of retroperitoneal hematoma expansion after a seatbelt injury.

A case of retroperitoneal fibrosis responding to steroid therapy

Directory of Open Access Journals (Sweden)

Ryuta Watanabe

Full Text Available ABSTRACT A 69-year-old man presented at the hospital with complaints of prolonged stomach pain extending from the week prior. Enhanced computed tomography (CT revealed a low density area in the retroperitoneal space. A radiologist diagnosed the patient with retroperitoneal fibrosis. One week later, an enhanced CT revealed an exponential increase of the low density area and slight right hydronephrosis. Upon admission, prednisolone administration was initiated at a dose of 40mg/day. The size of the retroperitoneal soft tissue mass decreased gradually. Although the dose of prednisolone was tapered to 5mg, the patient is doing well without any sign of recurrence.

Giant retroperitoneal lipoma in an infant | Mohammed | Journal of ...

African Journals Online (AJOL)

Retroperitoneal lipomas have remained the essentially rare tumors seen in clinical practice. The tumors are rarer in children, with very few reported cases in surgical literature worldwide. We are reporting the case of a six-month-old child who presented with a giant retroperitoneal lipoma that was successfully managed by ...

Retroperitoneal lipo sarcoma: report of 6 cases

International Nuclear Information System (INIS)

Santamarina, Mario G.; Baltazar, Alberto D.; Stagno, Diego; Kristal, Marcos; Lopez, Jessica

2003-01-01

Objective: To determine CT and MRI imaging features in patients with a diagnosis of retroperitoneal lipo sarcoma. Material and Methods: Retrospective analysis of 6 cases, studied with CT and/or MRI in patients with retroperitoneal lipo sarcoma during the last 4 years at our institution. We analyzed symptoms, treatment and prognosis with special focus on the CT and MRI findings and their histological correlation. Results: the most frequent histological subtype in our group of patients was the pleomorphic lipo sarcoma (n=3). In the others cases, 2 were well differentiated and one was round-cell type. Retroperitoneal lipo sarcoma, especially the well differentiated, presented certain imaging patterns which allowed to suspect the subtype of tumor. Recurrences occurred in 50% (n=3). Mortality rate was 33.4% (n=2) (follow-up, 16 months). Conclusion: Both CT and MRI are methods which aid in the detection of this rare disorder, as well as in its diagnosis and follow-up. (author)

First case report of retroperitoneal metastasis of fascioliasis after surgery

Science.gov (United States)

Wang, Jun-Ke; Ma, Wen-Jie; Lu, Qiang; Zheng, Er-Liang; Yang, Qin; Hu, Hai-Jie; Liu, Fei; Li, Quan-Sheng; Li, Fu-Yu

2017-01-01

Abstract Rationale: Fascioliasis is a rare cause of liver abscesses, and its clinical course consists of hepatic phase and biliary phase. Patient concerns: We describe a 58-year-old female patient who presented with a 2-month history of intermittent fever and abdominal pain. An abdominal computed tomography (CT) revealed confluent low-density lesions in the liver. Complete surgical resection of these abscesses was performed, and postoperative pathological examination and serological tests confirmed a diagnosis of fascioliasis. However, 4 months after the surgery, follow-up CT revealed a lesion in the retroperitoneal area. Meanwhile, ultrasonography-guided percutaneous needle biopsy of the retroperitoneal lesion was performed, and a parasitic infection was suspected. Diagnoses: Retroperitoneal metastasis of hepatic phase fascioliasis. Interventions: The patient received parasitic resistance treatment with triclabendazole at a dose of 10 mg/kg/d for 2 consecutive days. Outcomes: After 2 courses of triclabendazole therapy, the retroperitoneal metastasis regressed to a minor lesion. Lessons: To the best of our knowledge, this is the first case report of retroperitoneal metastasis of fascioliasis, aimed at helping recognize the clinical features and treatment options of this rare disease. PMID:29390366

First case report of retroperitoneal metastasis of fascioliasis after surgery.

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Wang, Jun-Ke; Ma, Wen-Jie; Lu, Qiang; Zheng, Er-Liang; Yang, Qin; Hu, Hai-Jie; Liu, Fei; Li, Quan-Sheng; Li, Fu-Yu

2017-12-01

Fascioliasis is a rare cause of liver abscesses, and its clinical course consists of hepatic phase and biliary phase. We describe a 58-year-old female patient who presented with a 2-month history of intermittent fever and abdominal pain. An abdominal computed tomography (CT) revealed confluent low-density lesions in the liver. Complete surgical resection of these abscesses was performed, and postoperative pathological examination and serological tests confirmed a diagnosis of fascioliasis. However, 4 months after the surgery, follow-up CT revealed a lesion in the retroperitoneal area. Meanwhile, ultrasonography-guided percutaneous needle biopsy of the retroperitoneal lesion was performed, and a parasitic infection was suspected. Retroperitoneal metastasis of hepatic phase fascioliasis. The patient received parasitic resistance treatment with triclabendazole at a dose of 10 mg/kg/d for 2 consecutive days. After 2 courses of triclabendazole therapy, the retroperitoneal metastasis regressed to a minor lesion. To the best of our knowledge, this is the first case report of retroperitoneal metastasis of fascioliasis, aimed at helping recognize the clinical features and treatment options of this rare disease. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

Dedifferentiated retroperitoneal liposarcoma presenting as right inguinal hernia: A case report

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Kim, Jung Myung; Lee, Su Lim; Ku, Young Mi [Dept. of Radiology, Uijeongbu St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu (Korea, Republic of); Choi, Moon Hyung [Dept. of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

2016-01-15

Retroperitoneal liposarcomas usually present as painless, slow-growing abdominal masses. When masses grow large enough to compress surrounding structures, symptoms may occur. Retroperitoneal liposarcoma clinically manifesting as inguinal hernia is a very rare entity; only 11 cases have been reported. Herein, we present radiographic features of a 37-year-old male with a painless palpable mass in the right groin that was identified as dedifferentiated retroperitoneal liposarcoma herniated through the right inguinal canal.

Guided fine needle aspiration cytology of retroperitoneal masses - Our experience

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Mimi Gangopadhyay

2011-01-01

Full Text Available Background : Early pathological classification of retroperitoneal masses is important for pin-point diagnosis and timely management. Aims : This study was done to evaluate the usefulness and drawbacks of guided fine needle aspiration cytology (FNAC of retroperitoneal masses covering a period of two years with an intention to distinguish between neoplastic and non-neoplastic lesions and to correlate with histologic findings. Materials and Methods : FNAC was done under radiological guidance in all cases using long needle fitted with disposable syringe. Appropriate staining was done and cytology was correlated with histology which was taken as the gold standard for comparison. Results : Fifty-one patients who presented with retroperitoneal masses were studied. Forty-four lesions were malignant cytologically and 7 were inflammatory (tuberculous. According to radiological and cytologic findings, we classified our cases into four groups: renal tumors, retroperitoneal lymphadenopathy, germ cell tumors, soft tissue tumors. Except for cases of non-Hodgkin lymphoma (NHL and metastatic lesions, we had sensitivity and specificity of 100%. In NHL the sensitivity and specificity were both 50%. In cases of metastatic adenocarcinoma, the sensitivity and specificity were 84.6% and 81.8%, respectively. Conclusions : Ignoring the pitfalls, guided FNAC is still an inexpensive and reliable method of early diagnosis of retroperitoneal lesions.

Nonsurgical treatment of aggressive fibromatosis in the head and neck

International Nuclear Information System (INIS)

West, C.B. Jr.; Shagets, F.W.; Mansfield, M.J.

1989-01-01

Aggressive fibromatosis is a poorly defined, locally aggressive, yet histologically benign fibroblastic proliferative lesion that may occur in the head and neck. The lesion is highly cellular and locally infiltrative and has a propensity to invade and erode bone, compromising vital structures within the head and neck. However, it is not a true malignancy because it does not have malignant cytologic characteristics nor does it metastasize. We present two cases of aggressive fibromatosis occurring in young adult men. The first case involved a rapidly enlarging mass of the anterior maxilla that involved the upper lip, nasal alae, nasal septum, inferior turbinates, and hard palate. The patient underwent incisional biopsy to confirm the diagnosis. Because of difficulty in determining the actual margins of this extensive lesion and the significant morbidity that would have resulted from surgical resection, we elected to treat this patient with chemotherapy and radiation therapy. The second case was an extensive lesion involving the right temporal bone, pterygomaxillary space, and infratemporal, temporal, and middle cranial fossae. Incisional biopsy confirmed the diagnosis. Because of the lack of functional and cosmetic deficits and the unavoidable morbidity of a surgical resection, this patient was treated with radiation therapy. Although wide field resection is the most satisfactory form of treatment, in situations in which this modality would result in unacceptable morbidity or if surgical margins are positive, then radiation therapy and chemotherapy should be considered. Support for these therapeutic modalities is found in larger series of cases outside the head and neck

Primary retroperitoneal seminoma - embryology, histopathology and treatment particularities.

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Gîngu, Constantin Virgil; Mihai, Mihaela; Baston, Cătălin; Crăsneanu, Mugurel Alexandru; Dick, Alexandru Vladimir; Olaru, Vlad; Sinescu, Ioanel

2016-01-01

Retroperitoneal seminoma is a very rare form of cancer, with embryological origin represented by primordial germ cells from the urogenital ridges left behind during the fetal development. Extragenital germ cell tumors can also occur in the mediastinum or the pineal gland. The aim of this paper is to outline the particularities and draw embryological, histopatological and treatment conclusions regarding extragonadal germ cell tumors. A 43-year-old patient without any additional pathology was admitted for anemia of unknown etiology. The clinical examination revealed through deep abdominal palpation a mass in the left flank, and normal testes. Thoraco-abdomino-pelvic computed tomography (CT) scan showed a large retroperitoneal tumor adjacent to the great vessels in the left lumbo-iliac region. The blood work revealed just a low hemoglobin and hematocrit. With the established diagnosis of retroperitoneal tumor, radical surgical removal was decided. During the surgery, we were required to dissect a large solid encapsulated tumor mass from the aorta and the common iliac artery, starting at the renal pedicle all the way to the left iliac bifurcation. The surgical access was obtained through a transperitoneal left subcostal incision prolonged pararectally. Histopathological and immunohistochemical studies revealed a seminoma of the usual type. After the histological findings, the patient's tumor markers were investigated (LDH - lactate dehydrogenase, βHCG - beta-human chorionic gonadotropin, αFP - alpha-fetoprotein), all values being within normal ranges. In addition, the left testicle was thoroughly reexamined, clinically, through ultrasound and magnetic resonance imaging (MRI) scans, and no abnormalities were observed. After the surgery, the patient followed three courses of chemotherapy (BEP - Bleomycin, Etoposide and Cisplatin). The CT scan done 24 months after surgery found no signs of local or distant tumor recurrence. The patient entered a follow-up schedule

Percutaneous Radiofrequency Ablation for Treatment of Recurrent Retroperitoneal Liposarcoma

International Nuclear Information System (INIS)

Keil, Sebastian; Bruners, Philipp; Brehmer, Bernhard; Mahnken, Andreas Horst

2008-01-01

Percutaneous CT-guided radiofrequency ablation (RFA) is becoming more and more established in the treatment of various neoplasms, including retroperitoneal tumors of the kidneys and the adrenal glands. We report the case of RFA in a patient suffering from the third relapse of a retroperitoneal liposarcoma in the left psoas muscle. After repeated surgical resection and supportive radiation therapy of a primary retroperitoneal liposarcoma and two surgically treated recurrences, including replacement of the ureter by a fraction of the ileum, there was no option for further surgery. Thus, we considered RFA as the most suitable treatment option. Monopolar RFA was performed in a single session with a 2-cm umbrella-shaped LeVeen probe. During a 27-month follow-up period the patient remained free of tumor.

Lymphoplasmacytic Sclerosing Pancreatitis and Retroperitoneal Fibrosis

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Nigel K. F. Koo Ng

2008-01-01

Full Text Available Although cases of lymphoplasmacytic sclerosing pancreatitis (LSP associated with idiopathic retroperitoneal fibrosis have been reported, the association is rare. We describe a 74-year-old man who presented with obstructive jaundice and weight loss. Nineteen months earlier, he had been diagnosed with idiopathic retroperitoneal fibrosis and treated with bilateral ureteric stents. Initial investigations were suggestive of a diagnosis of LSP, however, a malignant cause could not be ruled out. He underwent an exploratory laparotomy and frozen sections confirmed the diagnosis of LSP. An internal biliary bypass was performed using a Roux loop of jejunum, and the patient made an uneventful recovery. This case illustrates the difficulty in distinguishing LSP from pancreatic carcinoma preoperatively.

Fibromatosis of the Sigmoid Colon With CTNNB1 (β-Catenin) Gene Mutation, Arising at the Site of Ileocolic Anastomosis for Resection of Gastrointestinal Stromal Tumor.

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Thway, Khin; Abou Sherif, Sara; Riddell, Angela M; Mudan, Satvinder

2016-05-01

We describe a case of intra-abdominal fibromatosis, which occurred in a 44-year-old woman who had a previous history of gastrointestinal stromal tumor (GIST) of the sigmoid mesocolon, which was treated with imatinib and resection. A mass was detected at the site of ileocolic anastomosis of the previous small bowel resection and sigmoid colectomy, nearly 3 years later. Clinically, this was suspected to represent recurrent GIST and was excised, but histology and mutational analysis showed desmoid-type fibromatosis with a mutation in codon 41 of exon 3 of the CTNNB1 (β-catenin) gene. The occurrence of fibromatosis at the site of excision of GIST is very rare, but its recognition is important as the treatment of the two neoplasms differs significantly. As imaging cannot reliably distinguish between these 2 entities, histological diagnosis is crucial for correct clinical management. © The Author(s) 2015.

Mortality risk factor analysis in colonic perforation: would retroperitoneal contamination increase mortality in colonic perforation?

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Yoo, Ri Na; Kye, Bong-Hyeon; Kim, Gun; Kim, Hyung Jin; Cho, Hyeon-Min

2017-10-01

Colonic perforation is a lethal condition presenting high morbidity and mortality in spite of urgent surgical treatment. This study investigated the surgical outcome of patients with colonic perforation associated with retroperitoneal contamination. Retrospective analysis was performed for 30 patients diagnosed with colonic perforation caused by either inflammation or ischemia who underwent urgent surgical treatment in our facility from January 2005 to December 2014. Patient characteristics were analyzed to find risk factors correlated with increased postoperative mortality. Using the Physiological and Operative Severity Score for the Enumeration of Mortality and Morbidity (POSSUM) audit system, the mortality and morbidity rates were estimated to verify the surgical outcomes. Patients with retroperitoneal contamination, defined by the presence of retroperitoneal air in the preoperative abdominopelvic CT, were compared to those without retroperitoneal contamination. Eight out of 30 patients (26.7%) with colonic perforation had died after urgent surgical treatment. Factors associated with mortality included age, American Society of Anesthesiologists (ASA) physical status classification, and the ischemic cause of colonic perforation. Three out of 6 patients (50%) who presented retroperitoneal contamination were deceased. Although the patients with retroperitoneal contamination did not show significant increase in the mortality rate, they showed significantly higher ASA physical status classification than those without retroperitoneal contamination. The mortality rate predicted from Portsmouth POSSUM was higher in the patients with retroperitoneal contamination. Patients presenting colonic perforation along with retroperitoneal contamination demonstrated severe comorbidity. However, retroperitoneal contamination was not found to be correlated with the mortality rate.

Retroperitoneal schwannoma: diagnostic imaging findings in 5 patients

International Nuclear Information System (INIS)

Baltazar, Alberto; Santamarina, Mario; Scalise, Gabriela; Ponce de Leon, Valeria; Bello, Lorena

2003-01-01

Purpose: To evaluate the different imaging findings (US, CT and MRI) in retroperitoneal schwannoma. Materials and methods: 5 patients (3 male and 2 females) with a diagnosis of retroperitoneal schwannoma were retrospectively evaluated. Ages ranged from 33 to 63 years (means 54 years). The images (US, CT and MR) were analyzed and correlated to histopathologic results. Results: The most frequent clinical finding was abdominal pain (60%). A presumptive diagnosis prior to surgery was suggested in 3/5 cases that had well-defined masses with a predominant cystic appearance. All patients underwent surgery with tumoral resection. Only 2 patients (40%) had recurrence within a three years period of follow-up. Conclusion: Retroperitoneal schwannoma is an infrequent tumor. In our series, no pathognomotic features were observed on US, CT or MRI. However, 3/5 tumors showed high signal intensity on T2-weighted images due to cystic areas. (author)

Misleading diagnosis of retroperitoneal actinomycosis

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Berchtenbreiter, C.; Bruening, R.; Reiser, M. [Inst. of Diagnostic Radiology, University Hospital Grosshadern, Ludwig Maximilians University, Munich (Germany); Auernhammer, A. [Medical Clinic II, Univ. Hospital Grosshadern, Ludwig Maximilians University, Munich (Germany)

1999-07-01

A 34-year-old woman presented with a left-sided suprarenal space-occupying lesion on sonography. Culture of material obtained during sonographic-guided puncture of the retroperitoneal lesion yielded a mixed flora of Actinomyces and Peptostreptococcus. Initially, a misleading diagnosis of an adrenal pheochromocytoma was initiated by highly positive metaiodobenzylguanidine scintigraphy after chemical chemistry vanillylmandelic acid (VMA) test showed elevated values for adrenaline and its derivatives. Retroperitoneal actinomycosis with yet unproven spread into thoracic and cervical compartments is a particular unusual presentation of an infection with these organisms. Because it may mimic subacute infections or malignant masses in terms of clinical and laboratory findings, radiological diagnosis of this entity may be difficult. The diagnosis was based on results of culture and the response of the patient to long-term penicillin-derivate therapy after surgical drainage of the suprarenal abscess formation. (orig.)

Gigantic teratoma - retroperitoneal tumor: a case report; Teratoma gigante - tumor retroperitoneal: relato de um caso

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Figueiredo, Rossana Lopes de [Paraiba Univ., Campina Grande, PB (Brazil). Faculdade de Medicina; Franca Costa, Hamilton Belo de [Hospital Geral de Campina Grande, PB (Brazil); [Clinica Pronto-Socorro Infantil, Campina Grande, PB (Brazil); Nobrega, Rosangela Figueiredo [Clinica Inside, Campina Grande, PB (Brazil); Toscano, Carlos Alberto Regis [Hospital Pedro I, Campina Grande, PB (Brazil)

1996-03-01

The authors report a case of primary retroperitoneal teratoma which has grown for seven years. the diagnosis was presumed through image diagnostic methods and it was confirmed after surgery and histopathology analysis. (author). 7 refs., 6 figs.

Intra-operative haemodynamic volatility in a patient undergoing retroperitoneal cyst excision

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Thrivikrama Padur Tantry

2012-01-01

Full Text Available Excision of a suspected retroperitoneal, duodenal duplication cyst was performed in a pre-operatively normotensive patient under combined epidural and general anaesthesia. Intraoperatively, the cystic tumour was discovered to be a retroperitoneal mass, free from duodenal or adrenal origin. Development of severe arrhythmias, ST segment changes and hypertensive spikes during cyst handling and dissection suggested the possibility of a catecholamine-secreting tumour. These were managed effectively with pharmacological agents. Subsequently, histopathology of the specimen revealed a paraganglioma. Vasoactive tumour has to be suspected in every patient undergoing anaesthesia for retroperitoneal cystic lesion.

Outcome of surgery for primary and recurrent desmoid-type fibromatosis. A retrospective case series of 174 patients

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Panagiotis Tsagozis, BSc, MD, PhD

2017-05-01

Conclusions: A complete primary excision is the best window of opportunity to achieve local control of desmoid-type fibromatosis. Once the disease relapses, surgical intervention is accompanied with a high risk of failure, irrespective of the quality of the margins and adjuvant treatment given.

Retroperitoneal Angiomatoid Fibrous Histiocytoma Presenting as a Recurrent Spontaneous Retroperitoneal Hemorrhage in a 9-Year-Old Boy.

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Slack, Jonathan C; Sanchez-Glanville, Carlos; Steele, MacGregor; Wong, Andrew L; Bründler, Marie-Anne

2018-05-01

Angiomatoid fibrous histiocytoma (AFH) is a rare soft tissue tumor that typically presents in children and young adults. Occurrence outside of the extremities and the head and neck region is exceedingly rare. We report the case of a 9-year-old boy who presented with recurrent retroperitoneal hemorrhage initially thought to be a manifestation of an underlying bleeding disorder. After comprehensive diagnostic work-up, including multiple negative biopsies, the patient underwent surgical resection of an extensively hemorrhagic intramuscular mass and to date remains well. Pathologic examination confirmed AFH with EWSR1 gene rearrangement. This first documented report of an AFH in a retroperitoneal location in a child highlights the diagnostic difficulties and clinical challenges of AFH arising in an atypical location.

The Value of Surgery for Retroperitoneal Sarcoma

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Sepideh Gholami

2009-01-01

Full Text Available Introduction. Retroperitoneal sarcomas are uncommon large malignant tumors. Methods. Forty-one consecutive patients with localized retroperitoneal sarcoma were retrospectively studied. Results. Median age was 58 years (range 20–91 years. Median tumor size was 17.5 cm (range 4–41 cm. Only 2 tumors were <5 cm. Most were liposarcoma (44% and high-grade (59%. 59% were stage 3 and the rest was stage 1. Median followup was 10 months (range 1–106 months. Thirty-eight patients had an initial complete resection; 15 (37% developed recurrent sarcoma and 12 (80% had a second complete resection. Patients with an initial complete resection had a 5-year survival of 46%. For all patients, tumor grade affected overall survival (=.006. Complete surgical resection improved overall survival for high-grade tumors (=.03. Conclusions. Tumor grade/stage and complete surgical resection for high-grade tumors are important prognostic variables. Radiation therapy or chemotherapy had no significant impact on overall or recurrence-free survival. Complete surgical resection is the treatment of choice for patients with initial and locally recurrent retroperitoneal sarcoma.

RETROPERITONEAL LAPAROSCOPIC TREATMENT OF LARGE ...

African Journals Online (AJOL)

Conclusion Retroperitoneal laparoscopic ureterolithotomy is a good minimally invasive alternative line of treatment for ureteral stones in cases not amenable for ESWL or endoscopy. However, it takes a long learning curve. Moreover, a careful case selection and good working instruments are necessary for success.

A Retroperitoneal Isolated Enteric Duplication Cyst Mimicking a Teratoma: A Case Report and Literature Review

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Daichi Momosaka

2016-01-01

Full Text Available Enteric duplication cysts lacking anatomic association with the gastrointestinal tract are called isolated enteric duplication cysts (IEDCs. We present an atypical case of a retroperitoneal IEDC with a tortuous tubular complex shape that enfolded the surrounding retroperitoneal fat and mimicked a retroperitoneal teratoma. Multiplanar reconstruction images should be used to evaluate such a lesion correctly. A tortuous tubular complex shape could be a key finding to differentiate from other retroperitoneal cysts.

Robotic retroperitoneal partial nephrectomy: a step-by-step guide.

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Ghani, Khurshid R; Porter, James; Menon, Mani; Rogers, Craig

2014-08-01

To describe a step-by-step guide for successful implementation of the retroperitoneal approach to robotic partial nephrectomy (RPN) PATIENTS AND METHODS: The patient is placed in the flank position and the table fully flexed to increase the space between the 12th rib and iliac crest. Access to the retroperitoneal space is obtained using a balloon-dilating device. Ports include a 12-mm camera port, two 8-mm robotic ports and a 12-mm assistant port placed in the anterior axillary line cephalad to the anterior superior iliac spine, and 7-8 cm caudal to the ipsilateral robotic port. Positioning and port placement strategies for successful technique include: (i) Docking robot directly over the patient's head parallel to the spine; (ii) incision for camera port ≈1.9 cm (1 fingerbreadth) above the iliac crest, lateral to the triangle of Petit; (iii) Seldinger technique insertion of kidney-shaped balloon dilator into retroperitoneal space; (iv) Maximising distance between all ports; (v) Ensuring camera arm is placed in the outer part of the 'sweet spot'. The retroperitoneal approach to RPN permits direct access to the renal hilum, no need for bowel mobilisation and excellent visualisation of posteriorly located tumours. © 2014 The Authors. BJU International © 2014 BJU International.

The retroperitoneal interfascial planes: current overview and future perspectives.

Science.gov (United States)

Ishikawa, Kazuo; Nakao, Shota; Nakamuro, Makoto; Huang, Tai-Ping; Nakano, Hiroshi

2016-07-01

Recently, the concept of interfascial planes has become the prevalent theory among radiologists for understanding the retroperitoneal anatomy, having replaced the classic tricompartmental theory. However, it is a little known fact that the concept remains incomplete and includes embryological errors, which have been revised on the basis of our microscopic study. We believe that the concept not only provides a much clearer understanding of the retroperitoneal anatomy, but it also allows further development for diagnosis and treatment of retroperitoneal injuries and diseases, should it become an accomplished theory. We explain the history and outline of the concept of interfascial planes, correct common misunderstandings about the concept, explain the unconsciously applied therapeutic procedures based on the concept, and present future perspectives of the concept using our published and unpublished data. This knowledge could be essential to acute care physicians and surgeons sometime soon.

A retroperitoneal foregut duplication cyst: a case report

International Nuclear Information System (INIS)

Kim, Yong Woon; Lee, Jin Hee; Byun, Kyung Hwan; Kim, Byung Ki; Sohn, Kyung Sik; Kee, Se Kook; Jeon, Jin Min; Yun, Young Kook

2006-01-01

Retroperitoneal foregut duplication cyst is an extremely rare congenital malformation. Pathologically, this lesion contains both gastric mucosa and respiratory type mucosa; radiologically, it is often challenging to differentiate it from the other cystic neoplasms that present a similar appearance. We report on a case of retroperitoneal foregut duplication cyst that was lined by both gastric and pseudostratified ciliated columnar epithelium, and it was also accompanied by a pancreatic pseudocyst. Initially, it presented with peripancreatic and intrapancreatic cystic masses in an asymptomatic 30-year-old man, and this man has since undergone surgical resection

Indications for radiation therapy and surgery in the treatment of fibromatosis

International Nuclear Information System (INIS)

Spear, M.A.; Jennings, L.C.; Efird, J.T.; Mankin, H.J.; Springfield, D.S.; Gebhardt, M.C.; Spiro, I.J.; Rosenberg, A.E.; Suit, H.D.

1995-01-01

Purpose: To determine the roles of radiation and surgery in treating fibromatosis (desmoid tumors). Methods and Materials: Records of 92 patients treated at the Massachusetts General Hospital between 1971 and 1992 were analyzed. Treatment consisted of: radiation, 15 tumors; surgery, 37 tumors; radiation plus surgery, 40 tumors. Radiation doses ranged from 10 Gy to 72 Gy, and were delivered as megavoltage external beam, brachytherapy or a combination. Minimum follow up was 1 year (median 6.2 yrs). The margin status of resected specimens included: 14 negative, 11 negative at 18 yrs and 0% for age <18 yrs. Conclusions: Surgery remains the primary treatment of choice for fibromatosis. Radiation therapy, however, is also effective either as a primary treatment or a surgical adjuvent. Additional advantage in recurrence free survival with peri-operative treatment was seen in patients for whom negative margins were not achieved. Thus, radiation might be recommended to these patients, particularly if the lesion is located such that further recurrence and resection could result in a significant functional or cosmetic defect. Radiation would also be recommended as a primary therapy for those in which a primary resection could not be expected without such deficits. It should also be noted when considering the potential consequences of recurrence that these lesions may often fail locally even with negative margins. Of further interest lesions located in the planter or palmer regions appear as a different disease entity, with a very benign course in adults and an extremely aggressive course in children

Retroperitoneal "triton" tumor. Report of a case and review of literature

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Palacios Acosta José Martín

2014-07-01

Full Text Available The triton tumor was described in 1932 by Masson, as a peripheral nerve sheath malignancy with rabdomioblástica differentiation. The retroperitoneal location is extremely rare, only nine cases have been reported in children. The clinical picture depends on the size of the tumor and the organs involved, their retroperitoneal location is usually asymptomatic. The mainstay of treatment is the surgical excision of the tumor. We report the case of a child with retroperitoneal location of the tumor. A complete resection of it was performed. The patient had an uneventful postoperative course. He is currently under control. There is no evidence of relapse.

The clinical implications of variants of vena cava inferior and aorta on retroperitoneal surgery

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S. V. Mukhtarulina

2014-12-01

Full Text Available Objective: to study variants of retroperitoneal vascular structure and its clinical implications on retroperitoneal surgery in patients with cervical cancer IA–IIB stage.Materials and methods. 101 patients who underwent paraaortic and bilateral pelvic lymphadenectomy were included in this study. 10 patients of the first group with anomalies of inferior vena cava, renal arteries and veins, common iliac vein and ovarian vessels were compared with 91 patients of the second group without anomalies.Results. Variants of major retroperitoneal vascular structure were present in 10 (9.9 % patients. Supernumerary renal arteries and veins observed in 5 (4.9 % patients; retroaortic left renal vein type I and II – in 3 (3.0 % patients. Double vena cava inferior detected in 1 (1.0 % patient. Patients with variants of retroperitoneal vascular structures hadn’t vessel injury. There was no difference in intraoperative hemorrhage, transfusion red blood cell, rate of intraoperative hemoglobin and removed paraaortic lymph nodes between the groups. Risk factors for intraoperative bleeding in patients with cervical cancer, depending on the presence or absence of anomalies of retroperitoneal vessels had no significant difference.Conclusion. Despite the fact that the variants of retroperitoneal vascular structures are rare (9.9 %, the success of retroperitoneal surgery is associated with the knowledge of vascular variations which decrease serious, life-threatening complications.

Retroperitoneal disorders associated with IgG4-related autoimmune pancreatitis

OpenAIRE

Hara, Noboru; Kawaguchi, Makoto; Takeda, Keisuke; Zen, Yoh

2014-01-01

IgG4-related autoimmune pancreatitis is frequently accompanied by relevant lesions in the genitourinary tract and retroperitoneal organs, which cause various clinical problems, ranging from non-specific back pain or bladder outlet obstruction to renal failure. The diagnosis of IgG4-related retroperitoneal fibrosis requires a multidisciplinary approach, including serological tests, histological examination, imaging analysis, and susceptibility to steroid therapy. Radiological examinations are ...

"Whisking of ugly tissue"… A surgical management of gingival fibromatosis in a 15-year-old girl: A rare case report

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Srinivasa Tenkasale Siddeshappa

2015-01-01

Full Text Available Gingival fibromatosis is a condition characterized by a slow, progressive increase in the gingival tissue that develops as either an isolated disorder or as part of the clinical characteristics of diverse syndrome. The present case report describes a rare case of gingival fibromatosis and its management using scalpel in combination with electrosurgery. A 15-year-old girl patient presented with a chief complaint of gingival overgrowth covering all the surfaces upper and lower teeth. The growth was excised with periodontal knife in combination with electrosurgery under local anesthesia. After 1-year of follow-up, healing was uneventful with no recurrence. Combined technique for the removal of gingival overgrowth represents a unique treatment approach where minimal postoperative bleeding and discomfort were observed.

A huge renal capsular leiomyoma mimicking retroperitoneal sarcoma

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Lal Anupam

2009-01-01

Full Text Available A huge left renal capsular leiomyoma mimicking retroperitoneal sarcoma presented in a patient as an abdominal mass. Computed tomography displayed a large heterogeneous retro-peritoneal mass in the left side of the abdomen with inferior and medial displacement as well as loss of fat plane with the left kidney. Surgical exploration revealed a capsulated mass that was tightly adherent to the left kidney; therefore, total tumor resection with radical left nephrectomy was performed. Histopathology ultimately confirmed the benign nature of the mass. This is the largest leiomyoma reported in literature to the best of our knowledge.

Does negative retroperitoneal CT in adolescents with paratesticular rhabdomyosarcoma preclude the need of retroperitoneal lymph node dissection?; A tomografia de retroperitoneo normal em adolescentes com rabdomiossarcoma paratesticular afasta necessidade de linfadenectomia?

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Damazio, Eulalio [Hospital Lucano, Teresina (PI) (Brazil); Caran, Eliana [Instituto de Oncologia Pediatrica, Universidade Federal de Sao Paulo - UNIFESP, Sao Paulo, SP (Brazil); Ortiz, Valdemar; Macedo Junior, Antonio, E-mail: macedo.dcir@epm.br [Departamento de Urologia, Universidade Federal de Sao Paulo - UNIFESP, Sao Paulo, SP (Brazil)

2011-07-01

We report on a 16-year-old male with paratesticular rhabdomyosarcoma who underwent retroperitoneal lymph node dissection due to a stage I tumor (normal retroperitoneal computed tomography). The surgical finding was three enlarged nodes, positive for metastatic disease. Patient was referred to adjuvant chemotherapy. This case suggests that the Intergroup Rhabdomyosarcoma Study Group IV protocol is subject to questions regarding adolescents with paratesticular rhabdomyosarcoma, and that negative retroperitoneal CT does not preclude the need of lymph node dissection. (author)

Renal fascial network in retroperitoneal extension of pathologic processes

International Nuclear Information System (INIS)

Raptopoulos, V.; Kleinman, P.K.; Marks, S.C. Jr.; Davidoff, A.

1987-01-01

The concept of the fascial network emerged after careful analysis of CT scans of 100 patients with a variety of retroperitoneal abnormalities, and after correlation of CT scans and anatomic dissections performed on eight unembalmed cadavers in which different-colored barium-mixed liquid latex was injected in various retroperitoneal compartments. Fat lobules are supported and connected with each other by surrounding thin layers of connective tissue. Thicker connective tissue lamellae (septa) connect and support organs and fascia. Thus, a fascial network infrastructure exists in which fat lobules act as mechanical barriers to the spread of pathologic processes, while these processes tend to take the course of least resistance by spreading along or dissecting within fascial and septal planes. The fascial network acts as a roadway, conduit, and barrier to spread in the retroperitoneum and fatty tissue in general. The insights afforded by the fascial network concept unwind the traditional views regarding the dynamics of retroperitoneal pathology

Desmoid fibromatosis: MRI features of response to systemic therapy

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Sheth, Pooja J.; Subhawong, Ty K. [University of Miami Miller School of Medicine/Jackson Memorial Hospital, Department of Radiology, Miami, FL (United States); Del Moral, Spencer; Wilky, Breelyn A.; Trent, Jonathan C. [University of Miami Miller School of Medicine/Sylvester Comprehensive Cancer Center, Division of Hematology/Oncology, Department of Medicine, Miami, FL (United States); Cohen, Jonathan [Oncology and Radiation Associates, Miami, FL (United States); Rosenberg, Andrew E. [University of Miami Miller School of Medicine, Department of Pathology, Miami, FL (United States); Temple, H.T. [Center for Orthopedic Innovations, Miami, FL (United States)

2016-10-15

Imaging criteria for measuring the response of desmoid fibromatosis to systemic therapy are not well established. We evaluated a series of patients with desmoids who underwent systemic therapy to document magnetic resonance imaging (MRI) features associated with a positive clinical response. This Institutional Review Board-approved retrospective study included 23 patients (mean age 40.5) with 29 extra-abdominal tumors. Therapeutic regimens included cytotoxic chemotherapy (n = 19), targeted therapy (n = 3), and nonsteroid anti-inflammatory drugs (NSAIDS; n = 1). Clinical effects were categorized as progressive disease, stable, or partial response. Maximum tumor dimension (D{sub max}), approximate tumor volume (V{sub Tumor}), and quantitative tumor T2 hyperintensity and contrast enhancement (relative to muscle) for pre- and post-treatment MRIs were compared. Three lesions progressed, 5 lesions were stable, whereas 21 showed a clinical response. D{sub max} decreased more in responders (mean -11.0 %) than in stable/progressive lesions (mean -3.6 and 0 % respectively, p = 0.28, ANOVA); by Response Evaluation Criteria in Solid Tumors (RECIST 1.1) 27 out of 29 lesions were ''stable,'' including the 3 progressive lesions. In responders, V{sub Tumor} change averaged -29.4 %, but -19.2 % and +32.5 % in stable and progressive lesions respectively (p = 0.002, ANOVA); by 3D criteria 14 out of 29 lesions showed a partial response. T2 hyperintensity decreased by 50-54 % in partial response/stable disease, but only by 10 % in progressive lesions (p = 0.049, t test). Changes in contrast enhancement ranged from -23 % to 0 %, but were not statistically significant among response groups (p = 0.37). Change in T2 hyperintensity showed a positive correlation with volumetric change (r = 0.40). Decreases in volume and T2 hyperintensity reflect the positive response of desmoid fibromatosis to systemic therapy; RECIST 1.1 criteria are not sensitive to clinically

IgG4-related retroperitoneal fibrosis: a newly characterized disease.

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Lian, Linjuan; Wang, Cong; Tian, Jian-Li

2016-11-01

Retroperitoneal fibrosis (RPF) is a rare disease characterized by chronic, nonspecific inflammatory and sclerotic or fibrotic tissue in the periaortic or periiliac retroperitoneum that encases adjacent structures. There will be a series of clinical manifestations once the proliferated fibrous tissues encase the abdominal aorta, iliac arteries and urinary duct. RPF is generally divided into two types: idiopathic retroperitoneal fibrosis (IRPF) without identified pathogenesis, making up about two-thirds of cases, and secondary retroperitoneal fibrosis. Recent studies on Immunoglobulin G4-related disease (IgG4-RD) reveal that abundant infiltration of IgG4 positive plasma cells is found in biopsies on the mass of RPF of some IRPF patients, which is identified as one spectrum of IgG4-RD and is named IgG4-related RPF. IgG4-related RPF is often misdiagnosed as retroperitoneal visceral malignancy and is treated with surgery. In addition, because of its good response to glucocorticoid, early detection and treatment is important. We review the definition, epidemiology, clinical features, diagnostic criteria, treatment and prognosis of IgG4-related RPF in this article to raise awareness of this newly characterized disease. © 2016 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.

A GIANT RETROPERITONEAL LIPOMA PRESENTING AS A SCIATIC HERNIA: MRI FINDINGS.

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Duran, S; Cavusoglu, M; Elverici, E; Unal, T D

2015-01-01

Sciatic hernia is a rare condition and its clinical diagnosis is uneasy. Herniation of pelvic organs as well as of retroperitoneal neoplasm has been reported in the literature. Sciatica occurs as a result of compression of the sciatic nerve by the herniated sac. We present a case of retroperitoneal lipoma in a patient who had lower leg complaint and describe the imaging findings.

Surgical anatomy of the retroperitoneal spaces--part I: embryogenesis and anatomy.

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Mirilas, Petros; Skandalakis, John E

2009-11-01

Embryologically, the retroperitoneal (extraperitoneal) connective tissue includes three strata, which respectively form the internal fascia lining of the body wall, the renal fascia, and the covering of the gastrointestinal viscera. All organs, vessels, and nerves, that lie on the posterior abdominal wall, along with their tissues and surrounding connective and fascial planes, are collectively referred to as the retroperitoneum. The retroperitoneal space is the area of the posterior abdominal wall that is located between the parietal peritoneum and the fascia. Within the greater retroperitoneal space, there are also several small spaces, or subcompartments. Loose connective tissue and fat surround the anatomic entities, and, to a variable degree, occupy the subcompartments. The multilaminar thoracolumbar (lumbodorsal) fascia begins at the occipital area and terminates at the sacrum.

Extra-Gastrointestinal Stromal Tumor of Retroperitoneal Origin: A Case Report

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Choi, Seung Joon; Kim, Hyung Sik; Park, Yul Ri; Choi, Hye Young [Dept. of Radiology, Gachon Medical Center, Gachon University of Medicine and Science, Incheon (Korea, Republic of)

2012-03-15

Extragastrointestinal stromal tumors (EGIST) are relatively rare, and cases originating in the retroperitoneum even rarer. We report a 60-year-old woman who presented with an EGIST originating in the retroperitoneum. Computed tomography results demonstrated a soft tissue mass on the right side of the retroperitoneum. The tumor abutted the duodenum, head of the pancreas, and right kidney. The mass was surgically proven to be a retroperitoneal tumor and histopathologically proven to be a retroperitoneal EGIST.

Giant Primary Retroperitoneal Teratoma in an Adult: A Case Report

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Poonam Mathur

2010-01-01

Full Text Available Teratomas are bizarre neoplasms derived from embryonic tissues that are typically found only in the gonadal and sacrococcygeal regions of adults. Retroperitoneal teratomas are rare and present challenging management options. We report here the case of a histologically unusual retroperitoneal tumor detected on computed tomography during the workup of abdominal pain in a 32-year-old male. The evaluation and treatment of this condition and a review of the literature are included in this paper.

Improved pathologic teeth migration following gingivectomy in a case of idiopathic gingival fibromatosis.

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Seki, Keisuke; Sato, Shuichi; Asano, Yukhiro; Akutagawa, Hideyasu; Ito, Koichi

2010-01-01

A case is reported of a 20-year-old woman with generalized severe gingival overgrowth covering almost all of the teeth with diastemata, diagnosed as idiopathic gingival fibromatosis. After initial therapy, the patient underwent surgery consisting of a full-mouth internal beveled gingivectomy. Postoperatively, the maxillary anterior teeth spontaneously moved to almost optimal positions. Removing the cause by gingivectomy can lead to spontaneous correction of the pathologic tooth migration. With supportive periodontal treatment, the patient showed no recurrence of gingival enlargement or repositioning of the teeth at the 5-year follow-up.

LAPAROSCOPIC MANAGEMENT OF RETROPERITONEAL INJURIES IN PENETRATING ABDOMINAL INJURIES.

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Mosai, F

2017-09-01

Laparoscopy in penetrating abdominal injuries is now accepted and practiced in many modern trauma centres. However its role in evaluating and managing retroperitoneal injuries is not yet well established. The aim of this study was to document our experience in using laparoscopy in a setting of penetrating abdominal injuries with suspected retroperitoneal injury in haemodynamically stable patients. A retrospective descriptive study of prospectively collected data from a trauma unit at Dr George Mukhari Academic Hospital (DGMAH) was done. All haemodynamically stable patients with penetrating abdominal injury who were offered laparoscopy from January 2012 to December 2015 were reviewed and those who met the inclusion criteria were analysed. A total of 284 patients with penetrating abdominal injuries were reviewed and 56 met the inclusion criteria and were analysed. The median age was 30.8 years (15-60 years) and males constituted 87.5% of the study population. The most common mechanism of injury was penetrating stab wounds (62.5%). Forty-five patients (80.3%) were managed laparoscopically, of these n=16 (28.5%) had retroperitoneal injuries that required surgical intervention. The most commonly injured organ was the colon (19.6%). The conversion rate was 19.6% with most common indication for conversion been active bleeding (14%). The complication rate was 7.14% (N=4) and were all Clavien-Dindo grade 3. There were no recorded missed injuries and no mortality. The positive outcomes documented in this study with no missed injuries and absence of mortality suggests that laparoscopy is a feasible option in managing stable patients with suspected retroperitoneal injuries.

Robotic posterior retroperitoneal adrenalectomy.

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Okoh, Alexis Kofi; Yigitbas, Hakan; Berber, Eren

2015-09-01

Since its initial description by Mercan et al. laparoscopic posterior retroperitoneal (PR) adrenalectomy has served as an alternaltive to the transabdominal (TL) approach for the treatment of adrenal pathologies. Robotic adrenal surgery has been reported to improve surgeon ergonomics and facilitate dissection. In patients with bilateral adrenal masses, PR adrenalectomy may be the approach of choice. We herein describe the technique, discuss its limitations and present a critical review of the current literature. © 2015 Wiley Periodicals, Inc.

Presentation of idiopathic retroperitoneal fibrosis at a young age: A rare case report.

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Minocha, Priyanka; Setia, Ankur

2016-11-01

Abdominal pain is a very common symptom in all age groups but retroperitoneal fibrosis is a rare differential diagnosis suspected in young patients presenting with nonspecific abdominal pain and symptoms of obstructive uropathy. Presented here is a case of a 16-year-old boy who presented with symptoms of persistent abdominal pain and a previous history of swelling in the left leg. A computed tomography (CT) scan suggested retroperitoneal fibrosis and an exploratory laparotomy and histopathological examination were performed for definitive diagnosis. This case report is intended to promote awareness of retroperitoneal fibrosis in young patients among health care providers.

Computerized tomography anatomy of the kidneys and retroperitoneal space

International Nuclear Information System (INIS)

Savchenko, A.P.; Mamaev, V.V.; Pkhakadze, Eh.G.

1989-01-01

The authors described the anatomy of the kidneys and retroperitoneal space in health on the basis of computerized tomography (CT) of 90 patients. Five typical levels in CT (ensuring all necessary data on roentgenomorphological trains of the kidneys and retroperitoneal space in the kidney area) were singled out. Some roentgenometric data on kidney cross-sections as well as the quantitative densitometric characterization of the parenchyma of the kidneys, renal sinus and adjacent tissues were presented. X-ray anatomy of the renal fiscia, pararenal space and perirenal fatty space of the kidney with different parts of the tetroperitoneal space was described

Gigantic teratoma - retroperitoneal tumor: a case report

International Nuclear Information System (INIS)

Figueiredo, Rossana Lopes de; Nobrega, Rosangela Figueiredo; Toscano, Carlos Alberto Regis

1996-01-01

The authors report a case of primary retroperitoneal teratoma which has grown for seven years. the diagnosis was presumed through image diagnostic methods and it was confirmed after surgery and histopathology analysis. (author). 7 refs., 6 figs

Two Case Reports and Actual Treatment Approachs of Retroperitoneal Fibrosis

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Eymen Gazel

2013-06-01

Full Text Available Retroperitoneal fibrosis (RPF is a rare disease of unclear etiology, which is characterized by a chronic non specific inflammation of the retroperitoneum. This inflammation of the retroperitoneum may entrap and obstruct retroperitoneal structures, particularly the ureters. Patients with RPF show non specific clinical symptoms, including poorly localized back pain, general malaise, weight loss, anemia, features of renal failure and occasionally, mild fever. The early symptoms are non specific and an accurate diagnosis is often achieved only subsequent to urological obstruction or the occurrence of renal failure. Although a number of scientific journals devoted to RPF are present in the litera¬ture, there is no accepted diagnostic or therapeutic strategy for this disease. However, there are several therapeutic strate¬gies which have been proven to be effective. Hereby, we reported two cases of retroperitoneal fibrosis which had similar symptoms and findings but different responses to medical treatment .We aimed to discuss challanges of RPF%u2019s diagnosis and the treatment protocol.

Gigantic retroperitoneal hematoma as a complication of anticoagulation therapy with heparin in therapeutic doses: a case report

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Daliakopoulos Stavros I

2008-05-01

Full Text Available Abstract Introduction Spontaneous retroperitoneal hemorrhage is a distinct clinical entity that can present as a rare life-threatening event characterized by sudden onset of bleeding into the retroperitoneal space, occurring in association with bleeding disorders, intratumoral bleeding, or ruptures of any retroperitoneal organ or aneurysm. The spontaneous form is the most infrequent retroperitoneal hemorrhage, causing significant morbidity and representing a diagnostic challenge. Case presentation We report the case of a patient with coronary artery disease who presented with transient ischemic attack, in whom anticoagulant therapy with heparin precipitated a massive spontaneous atraumatic retroperitoneal hemorrhage (with international normalized ratio 2.4, which was treated conservatively. Conclusion Delay in diagnosis is potentially fatal and high clinical suspicion remains crucial. Finally, it is a matter of controversy whether retroperitoneal hematomas should be surgically evacuated or conservatively treated and the final decision should be made after taking into consideration patient's general condition and the possibility of permanent femoral or sciatic neuropathy due to compression syndrome.

Delays in the management of retroperitoneal sarcomas

DEFF Research Database (Denmark)

Seinen, Jojanneke; Almquist, Martin; Styring, Emelie

2010-01-01

Retroperitoneal sarcomas are rare and treatment should optimally be centralized. Despite successful centralization with 90% of the patients referred prior to surgery, delays occur, which led us to assess lead times in a population-based series. Method. Patients diagnosed with retroperitoneal...... sarcoma in the southern Sweden health care region 2003-2009 were eligible for the study. Data on referrals and diagnostic investigations were collected from clinical files from primary health care, local hospitals, and from the sarcoma centre. Lead times were divided into patient delays and health care...... at the general practitioner, 36 days at local hospitals, and 55 days at the sarcoma centre. Conclusion. Centralization per se is not sufficient for optimized and efficient management. Our findings suggest that delays can be minimized by direct referral of patients from primary health care to sarcoma centers...

Type IV Ehlers-Danlos Syndrome: A Surgical Emergency? A Case of Massive Retroperitoneal Hemorrhage

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Chun, Stephen G; Pedro, Patrick; Yu, Mihae; Takanishi, Danny M

2011-01-01

Retroperitoneal hemorrhagic bleeding is a known manifestation of Type-IV Ehlers-Danlos Syndrome that is caused by loss-of-function mutations of the pro-alpha-1 chains of type III pro-collagen (COL3A1) resulting in vascular fragility. A number of previous reports describe futile surgical intervention for retroperitoneal bleeding in Type-IV Ehlers-Danlos Syndrome with high post-operative mortality, although the rarity of retroperitoneal bleeding associated with Type-IV Ehlers-Danlos Syndrome precludes an evidence-based approach to clinical management. We report a 23-year-old male with history of Type-IV Ehlers-Danlos Syndrome who presented with severe abdominal pain and tachycardia following an episode of vomiting. Further work-up of his abdominal pain revealed massive retroperitoneal bleeding by CT-scan of the abdomen. Given numerous cases of catastrophic injury caused by surgical intervention in Type-IV Ehlers-Danlos Syndrome, the patient was treated non-operatively, and the patient made a full recovery. This case suggests that even in cases of large retroperitoneal hemorrhages associated with Ehlers-Danlos Syndrome, it may not truly represent a surgical emergency. PMID:21966332

Retroperitoneal Haematoma in a Patient with Dengue Haemorrhagic Fever: A Rare Case Report.

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Singh, Jasminder; Singh, Harpreet; Sukhija, Gagandeep; Jagota, Ruchi; Bala, Saroj

2016-11-01

Dengue Haemorrhagic Fever (DHF) has diverse manifestations ranging from asymptomatic petechial skin haemorrhages to life threatening cerebral, pulmonary, gastrointestinal and genitourinary haemorrhages. However, the association of spontaneous retroperitoneal haematomas with DHF is not well documented in literature. We report a rare case of spontaneous retroperitoneal haematoma complicating DHF.

A Case of Advanced Unicentric Retroperitoneal Castleman's Disease, Associated With Psoriasis

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Mohammad Ali Mohagheghi

2017-05-01

Full Text Available We present here a 32-year-old male with advanced lately diagnosed, right sided retroperitoneal mass, which had been already treated due to progressive muco-cutaneous lesions clinically consistent with psoriasis, during recent four years. The advanced retroperitoneal mass resected surgically and reported as hyaline-vascular castleman disease with a dense focus of coarse calcification, on histopathology. Association of psoriasis and castlman disease is discussed in this case report. 

Delays in the management of retroperitoneal sarcomas

DEFF Research Database (Denmark)

Seinen, Jojanneke; Almquist, Martin; Styring, Emelie

2010-01-01

Retroperitoneal sarcomas are rare and treatment should optimally be centralized. Despite successful centralization with 90% of the patients referred prior to surgery, delays occur, which led us to assess lead times in a population-based series. Method. Patients diagnosed with retroperitoneal...... sarcoma in the southern Sweden health care region 2003-2009 were eligible for the study. Data on referrals and diagnostic investigations were collected from clinical files from primary health care, local hospitals, and from the sarcoma centre. Lead times were divided into patient delays and health care...... delays caused by primary health care, local hospitals, or procedures at the sarcoma centre. Results. Complete data were available from 33 patients and demonstrated a median patient delay of 23¿days (0-17¿months) and median health care delay of 94¿days (1-40¿months) with delays of median 15¿days...

Diffuse interstitial pulmonary infiltrate associated with retroperitoneal mass: report of two cases

International Nuclear Information System (INIS)

Teixeira, A.A.; Ramos, M.V.; Natal, M.R.C.

1990-01-01

The authors describe two cases of diffuse pulmonary interstitial infiltrate associated with retroperitoneal mass. Both patients were females and presented spontaneous pneumothorax. One of them had a typical hystological presentation of lymphangiomyomatosis and in the other on the retroperitoneal mass was classified as an angiomyolipoma. Angiomyomatosis are often associated with tuberous sclerosis and lymphangiomyomatosis. A review of the literature and the differential diagnosis are presented. (author)

Retroperitoneal ganglioneuroma in a young bodybuilder

International Nuclear Information System (INIS)

Durczynski, A.; Szymanski, D.; Hogendorf, P.; Strzelczyk, J.; Sporny, S.

2010-01-01

Background: Anabolic steroid intake is common among bodybuilders, although it is associated with a number of adverse effects, including tumorgenesis. Case Report: We describe the case of 24-year-old male athletic bodybuilder (weight 110 kg, height 179, BMI 34 kg/m 2 ) admitted to our department with diffused, intermittent, abdominal pain of 4 months duration. The patient had a history of long-term abuse of large doses of anabolic steroids of unknown origin. Computed tomography scans revealed a large, 140 x 100 mm, well-demarcated tumor, located between the left kidney, pancreas and spleen, presumably originating from the left kidney or adrenal gland. The tumor was proven to be hormonally inactive. Retroperitoneal tumor excision was performed with surrounding organs left intact. A final histopathologic examination revealed a well-differentiated 16 cm ganglioneuroma. Despite the rarity of its occurrence, ganglioneuromas must be considered in the differential diagnosis of retroperitoneal tumors. Conclusions: This unique finding raises questions concerning potential development of ganglioneuroma secondary to steroid abuse among bodybuilders. Bodybuilders should be made aware of the serious medical risks of steroid abuse. (authors)

Carbon Ion Radiotherapy for Unresectable Retroperitoneal Sarcomas

International Nuclear Information System (INIS)

Serizawa, Itsuko; Kagei, Kenji; Kamada, Tadashi; Imai, Reiko; Sugahara, Shinji; Okada, Tohru; Tsuji, Hiroshi; Ito, Hisao; Tsujii, Hirohiko

2009-01-01

Purpose: To evaluate the applicability of carbon ion radiotherapy (CIRT) for unresectable retroperitoneal sarcomas with regard to normal tissue morbidity and local tumor control. Methods and Materials: From May 1997 to February 2006, 24 patients (17 male and 7 female) with unresectable retroperitoneal sarcoma received CIRT. Age ranged from 16 to 77 years (median, 48.6 years). Of the patients, 16 had primary disease and 8 recurrent disease. Histologic diagnoses were as follows: malignant fibrous histiocytoma in 6, liposarcoma in 3, malignant peripheral nerve sheath tumor in 3, Ewing/primitive neuroectodermal tumor (PNET) in 2, and miscellaneous in 10 patients. The histologic grades were as follows: Grade 3 in 15, Grade 2-3 in 2, Grade 2 in 3, and unknown in 4. Clinical target volumes ranged between 57 cm 3 and 1,194 cm 3 (median 525 cm 3 ). The delivered carbon ion dose ranged from 52.8 to 73.6 GyE in 16 fixed fractions over 4 weeks. Results: The median follow-up was 36 months (range, 6-143 months). The overall survival rates at 2 and 5 years were 75% and 50%, respectively. The local control rates at 2 and 5 years were 77% and 69%. No complications of the gastrointestinal tract were encountered. No other toxicity greater than Grade 2 was observed. Conclusions: Use of CIRT is suggested to be effective and safe for retroperitoneal sarcomas. The results obtained with CIRT were a good overall survival rate and local control, notwithstanding the fact that most patients were not eligible for surgical resection and had high-grade sarcomas.

Retroperitoneal duplication cyst with a fistulous tract to the vagina: a case report.

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Filmar, Gilad A; Lotze, Peter M; Fisher, Hilaire W

2012-01-01

To describe a rare case of a retroperitoneal duplication cyst that fistulized to the vagina. Case description and discussion of a patient found to have an intestinal duplication cyst. A patient presented for a laparoscopic hysterectomy because of menorrhagia and a fibroid uterus. She also complained of recurrent urinary tract infections (UTIs) and a vaginal discharge. A retroperitoneal intestinal duplication cyst that fistulized to the vagina and caused her recurrent UTIs was identified. Surgical resection of the cyst resolved her complaint of recurrent UTIs. Retroperitoneal intestinal duplication cysts are rare congenital anomalies with vague clinical manifestations. The finding of a fistulous communication to the vagina originating from such a structure can be associated with recurrent UTIs.

Optimal management of primary retroperitoneal sarcoma: an update.

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Miah, Aisha B; Hannay, Jonathan; Benson, Charlotte; Thway, Khin; Messiou, Christina; Hayes, Andrew J; Strauss, Dirk C

2014-05-01

Soft tissue sarcomas are a group of heterogeneous neoplasms with more than 50 histological subtypes exhibiting major differences in terms of pathogenesis, genetic alterations and clinical behavior. Sarcomas represent approximately 1% of malignancies with retroperitoneal sarcomas representing 10-15% of all soft tissue sarcomas. Surgery is currently the only modality which offers the chance of cure. Surgery for retroperitoneal sarcomas presents specific challenges due their location in a complex space surrounded by vital structures and visceral organs often prohibiting resection with wide margins. Furthermore, even after complete resection local recurrence is common and the leading cause of death. In this article the authors describe the initial investigations, prognostic factors and optimal surgical management. The evidence and current research as regards the role of multimodality treatment is reviewed and discussed.

Radiological Findings of Primary Retroperitoneal Ewing Sarcoma

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Ulusan, S.; Koc, Z.; Tuba Canpolat, E.; Colakoglu, T. [Depts. of Radiology, Pathology, and General Surgery, Baskent Univ. Faculty of Medicine, Adana (Turkey)

2007-09-15

Ewing sarcomas are most commonly located in bone, while extra skeletal involvement of the retroperitoneum is extremely rare. We describe the radiologic and pathological findings in an adult patient with retroperitoneal extra skeletal Ewing sarcoma. Keywords: Color Doppler ultrasound; computed tomography; extra skeletal Ewing sarcoma; magnetic resonance imaging; ultrasound.

Radiological Findings of Primary Retroperitoneal Ewing Sarcoma

International Nuclear Information System (INIS)

Ulusan, S.; Koc, Z.; Tuba Canpolat, E.; Colakoglu, T.

2007-01-01

Ewing sarcomas are most commonly located in bone, while extra skeletal involvement of the retroperitoneum is extremely rare. We describe the radiologic and pathological findings in an adult patient with retroperitoneal extra skeletal Ewing sarcoma. Keywords: Color Doppler ultrasound; computed tomography; extra skeletal Ewing sarcoma; magnetic resonance imaging; ultrasound

Retroperitoneal extraadrenal paraganglioma report of two cases.

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Becheanu, G; Laky, D

1997-01-01

Two cases with retroperitoneal tumours affecting young women who cannot undergo surgery were investigated by biopsy and needle sampling. One of these cases presented a mainly alveolar histologic pattern and was easily diagnosed by immunohistochemical means, as well as a chromaffin paraganglioma. We discussed different diagnoses and approaches in the literature.

Laparoscopic management of retroperitoneal injuries from penetrating abdominal trauma in haemodynamically stable patients.

Science.gov (United States)

Koto, Modise Zacharia; Matsevych, Oleh Y; Mosai, Fusi; Balabyeki, Moses; Aldous, Colleen

2018-02-27

Laparoscopy is increasingly utilised in the trauma setting. However, its safety and reliability in evaluating and managing retroperitoneal injuries are not known. The aim of this study was to analyse our experience with laparoscopic management of retroperitoneal injuries due to penetrating abdominal trauma (PAT) and to investigate its feasibility, safety and accuracy in haemodynamically stable patients. Over a 4-year period, patients approached laparoscopically with retroperitoneal injuries were analysed. Mechanism, location and severity of injuries were recorded. Surgical procedures, conversion rate and reasons for conversion and outcomes were described. Of the 284 patients with PAT, 56 patients had involvement of retroperitoneum. Stab wounds accounted 62.5% of patients. The mean Injury Severity Score was 7.4 (4-20). Among retroperitoneal injuries, the colon (27%) was the most commonly involved hollow viscera followed by duodenum (5%). The kidney (5%) and the pancreas (4%) were the injured solid organs. The conversion rate was 19.6% and was mainly due to active bleeding (73%). Significantly more patients with gunshot wound were converted to laparotomy (38% vs. 9%). Therapeutic laparoscopy was performed in 36% of patients. There were no recorded missed injuries or mortality. Five (9%) patients developed the Clavien-Dindo Grade 3 complications, three were managed with reoperation, one with drainage/debridement and one with endovascular technique. Laparoscopic management of retroperitoneal injuries is safe and feasible in haemodynamically stable patients with PAT. However, a high conversion rate indicates difficulties in managing these injuries. The requirements are the dexterity in laparoscopy and readiness to convert in the event of bleeding.

Left retroperitoneal hydatid cyst disease and the treatment approach

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Alper Avcı

2013-12-01

Full Text Available Hydatid disease is one of the oldest diseases known to mankind. In 85-95% of the cases, the liver and/or the lung are involved and in only 5-15% the cyst occurs at the other sites. Echinococcal cysts are mostly found in the liver (60%-70% of cases, followed by the lungs (10%-25%, spleen, ovaries, kidneys, brain, bones and heart, but rarely elsewhere in the body. 1-3 Retroperitoneal location of hydatid cyst is encountered rarely and only occasional case reports have appeared since Lockhart and Sapinza first reported this entity in 1958. 4-6 Primary retroperitoneal hydatid cyst is extremely rare. Hydatid disease in extrahepatic locations usually remains asymptomatic unless the cyst grows and produces.

Retroperitoneal abscess after transanal minimally invasive surgery: case report and review of literature

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Aaron Raney

2017-10-01

Full Text Available Abscesses are a rare complication of transanal minimally invasive surgery and transanal endoscopic micro surgery. Reported cases have been in the rectal and pre-sacral areas and have been managed with either antibiotics alone or in conjunction with laparotomy and diverting colostomy. We report a case of a large retroperitoneal abscess following a Transanal minimally invasive surgery full thickness rectal polyp excision. The patient was successfully managed conservatively with antibiotics and a percutaneous drain. Retroperitoneal infection should be included in a differential diagnosis following a Transanal minimally invasive surgery procedure as the presentation can be insidious and timely intervention is needed to prevent further morbidity. Resumo: Os abscessos são uma complicação rara da cirurgia de ressecção transanal minimamente invasiva (TAMIS e da micro cirurgia endoscópica transanal (TEMS. Os casos notificados foram nas áreas rectal e pré-sacral e foram administrados com antibióticos isoladamente ou em conjunto com laparotomia e desvio de colostomia. Relatamos um caso de grande abscesso retroperitoneal após uma excisão de pólipo retal de espessura total TAMIS. O paciente foi tratado com sucesso com a administração de antibióticos e drenagem percutânea. Para prevenir mais morbidade é necessária incluir a infecção retroperitoneal no diagnostico diferencial após um procedimento TAMIS onde a apresentação pode ser insidiosa e a intervenção atempada. Keywords: Colorectal surgery, Transanal minimally invasive surgery (TAMIS, Retroperitoneal abscess, Natural orifice transluminal endoscopic surgery (NOTES, Single-site laparoscopic surgery (SILS, Surgical oncology, Palavras-chave: Cirurgia colorretal, Cirurgia de ressecção transanal minimamente invasiva (TAMIS, Abscesso retroperitoneal, Cirurgia endoscópica transluminal de orifício natural (NOTES, Cirurgia laparoscópica de único local (SILS, Oncologia cirúrgica

Retroperitoneal Schwannoma: A Rare Case

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Murat Kalaycı

2011-01-01

Case Presentation. A 38-year-old woman was admitted to the emergency service with the complaints of progressive abdominal pain and nausea for the last 24 hours. Abdominal examination was compatible with acute abdomen. Acute appendicitis was diagnosed by CT. During CT evaluation, a round shaped soft-tissue mass at the retroperitoneal area inferior to the right kidney was detected, The mass was resected and histology revealed schwannoma. Conclusion. Rare tumoral lesions with benign course such as schwannoma can be detected incidentally.

A rare life-threatening disease: unilateral kidney compressed by huge chronic spontaneous retroperitoneal hemorrhage

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Lu HY

2018-03-01

Full Text Available Hao-Yuan Lu,1,* Wei Wei,2,* Qi-Wei Chen,1,* Qing-Gui Meng,1 Gao-Hua Hu,1 Xian-Lin Yi,1,3 Xian-Zhong Bai1 1Department of Urology, Tumor Hospital of Guangxi Medical University and Guangxi Cancer Research Institute, Nanning 530021, China; 2Department of Radiology, Tumor Hospital of Guangxi Medical University and Guangxi Cancer Research Institute, Nanning 530021,China; 3Hubei Engineering Laboratory for Synthetic Microbiology, Wuhan Institute of Biotechnology, Wuhan 430075, China *These authors contributed equally to this work Objectives: To study an uncommon life-threatening disease, spontaneous retroperitoneal and perirenal hemorrhage. Case descriptions: A 69-year-old male presented with pain in the left waist and back of 1 month duration. The renal abscess was suspected by magnetic resonance imaging before operation. The perirenal hematoma was cleaned by operation. In another case, the patient had a functional solitary left kidney compressed by a huge retroperitoneal mass and uropenia appeared. Results: The first patient died of adult respiratory distress syndrome after surgery. The second patient died of cardiac insufficiency and pulmonary embolism on the second day after evacuation of retroperitoneal hematoma. Conclusion: Conservative surgery, such as selective arterial embolization, is a reasonable approach in patients with chronic spontaneous retroperitoneal and perirenal space hemorrhage and with poor general condition. We strongly recommend drainage or interventional therapy, but not a major surgery, in patients with poor condition. Keywords: kidney, spontaneous, retroperitoneal, hemorrhage, surgery

A rare case of a retroperitoneal enterogenous cyst with in-situ adenocarcinoma

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Woodland James G

2007-10-01

Full Text Available Abstract Background Retroperitoneal enterogenous cysts are uncommon and adenocarcinoma within such cysts is a rare complication. Case presentation We present the third described case of a retroperitoneal enterogenous cyst with adenocarcinomatous changes and only the second reported case whereby the cyst was not arising from any anatomical structure. Conclusion This case demonstrates the difficulties in making a diagnosis as well as the importance of a multi-disciplinary approach, and raises further questions regarding post-operative treatment with chemotherapy.

CT finding of right retroperitoneal space : analysis of extension of right perirenal hematoma

International Nuclear Information System (INIS)

Seo, Kwang Won; Kim, Kyung Rak; Lee, Hyeok; Kim, Young Hwa; Cho, Won Soo; Kim, Il Young

1997-01-01

To understand the structure and character of the right retroperitoneal space by analysis of the extension of retroperitoneal hematoma in patients with traumatic right renal injuries. We retrospectively reviewed CT scans of 13 patients with right retroperitoneal hematomas caused by right renal injury. At te renal level, we analyzed the relation of a hematoma contacting psoas muscle with other retroperitoneal compartmental hematomas. At the suprarenal level, a perirenal hematoma and a hematoma contacting the diaphragm were analyzed according to their relation with intrahepatic IVC and pericaval hematoma. Below renal hilar level, all hematomas contacting psoas muscle, observed in eight cases, were connected with retrorenal extension of anterior pararenal hematoma. At the suprarenal level, intrahepatic pericaval hematomas were not, in all 13 cases, connected with a hematoma contacting the diaphragm, but with a perirenal hematoma. At the upper suprarenal level, the only pericaval hematomas containing a medial component of perirenal hematoma extended superiorly to the upper one third of the tenth thoracic vertebral body. The anterior renal fascia envelops perirenal space except in its medial aspect. In the upper suprarenal region, the anterior and posterior planes of the anterior renal fascia unite to fuse with diaphragmatic fascia, but along the medial aspect they fuse with intrahepatic pericaval connective tissue and posteromedial diaphragm, respectively

Prolonged lymphatic leak after retroperitoneal lymph node dissection: a case report

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Browne Katherine M

2009-08-01

Full Text Available Abstract Introduction Persistent lymphatic drainage following retroperitoneal lymph node dissection for testicular tumor is an uncommon complication. Case presentation We describe a 21-year old man of Caucasian origin who had metastatic non-seminomatous germ cell tumor of the testis, and underwent retroperitoneal lymph node dissection, nephrectomy and partial inferior vena cava excision for a residual mass. The patient subsequently developed persistent lymphatic drainage causing foot drop that eventually responded to conservative medical and surgical measures. Conclusion This postoperative condition usually responds well to conservative measures but has the potential for serious morbidity if it is not managed appropriately.

Preliminary embryological study of the radiological concept of retroperitoneal interfascial planes: what are the interfascial planes?

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Ishikawa, Kazuo; Nakao, Shota; Murakami, Gen; Rodríguez-Vázquez, Jose Francisco; Matsuoka, Tetsuya; Nakamuro, Makoto; Shimazu, Takeshi

2014-12-01

Recently, the radiological concept of retroperitoneal interfascial planes has been widely accepted to explain the extension of retroperitoneal pathologies. This study aimed to explore embryologically based corroborative evidence, which remains to be elucidated, for this concept. Using serial or semi-serial transverse sections from 29 human fetuses at the 5th-25th week of fetal age, we microscopically observed the development of the retroperitoneal fasciae and other structures in the retroperitoneal connective tissue. A hypothesis for the formation of the interfascial planes was generated from the developmental study and analysis of retroperitoneal fasciae in computed tomography images from 224 patients. Whereas the loose connective tissue was uniformly distributed in the retroperitoneum by the 9th week, the primitive renal and transversalis fasciae appeared at the 10th-12th week, as previous research has noted. By the 23rd week, the renal fascia, transversalis fascia, and primitive adipose tissue of the flank pad emerged. In addition, the primitive lateroconal fascia, which runs parallel to and close to the posterior renal fascia, emerged between the renal fascia and the adipose tissue of the flank pad. Conversely, pre-existing loose connective tissue was sandwiched between the opposing fasciae and was compressed and narrowed by the developing organs and fatty tissues. Through this developmental study, we provided the hypothesis that the compressed loose connective tissue and both opposed fasciae compose the interfascial planes. Analysis of the thickened retroperitoneal fasciae in computed tomography images supported this hypothesis. Further developmental or histological studies are required to verify our hypothesis.

The Retrograde and Retroperitoneal Totally Laparoscopic Hysterectomy for Endometrial Cancer

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Eugenio Volpi

2012-01-01

Full Text Available Introduction. We retrospectively report our experience with the utilization of an original procedure for total laparoscopic hysterectomy based on completely retrograde and retroperitoneal technique for surgical staging and treatment of the endometrial cancer. The surgical, financial, and oncological advantages are here discussed. Methods. The technique used here has been based on a combination of a retroperitoneal approach with a retrograde and lateral dissection of the bladder and retrograde culdotomy with variable resection of parametrium. No disposable instruments and no uterine manipulator were utilized. Results. Intraoperative and postoperative complications were observed in 10% of the cases overall. Operative time length and mean haemoglobin drop value results were 129 min and 125 mL, respectively. Most patients were dismissed on days 3–5 from the hospital. Seventy-eight percent of the patients were alive with no evidence of disease at mean followup of 49 months. Conclusions. Our original laparoscopic technique is based on a retroperitoneal approach in order to rapidly control main uterine vessels coagulation, constantly check the ureter, and eventually decide type and site of lymph nodes removal. This procedure has important cost saving implications and the avoidance of uterine manipulator is of matter in case such as these of uterine malignancy.

Extended retroperitoneal necrotizing fasciitis with genital involvement, resembling fournier gangrene.

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Sugimoto, Motokazu; Matsuura, Kenji; Takayama, Hiroshi; Kayo, Munefumi; Ie, Tomotsugu

2010-10-01

Necrotizing fasciitis is a serious infection that originates in the subcutaneous tissues. Although many reports have been published about necrotizing infections of other anatomical sites, retroperitoneal necrotizing soft tissue infection is a rare entity that has been described in only a few case reports. The etiology and clinical course of retroperitoneal necrotizing fasciitis can be variable and it is often difficult to identify the etiology of the infective process. We report a 58-year-old man with rapidly progressive, gas-producing, necrotizing inflammation in the retroperitoneum, complicated with genital involvement resembling Fournier gangrene. The patient was managed successfully by aggressive drainage, debridement, and sequential laparotomies to track and control the extensive necrosis of the retroperitoneum and perineum, in addition to systemic care to control sepsis. After his general condition stabilized, early rectosigmoid adenocarcinoma was identified and resected curatively. He remained well at follow up, six months after discharge. In retrospect, the trigger of the disease process was unclear. Although it was believed possibly to be due to the colon lesion, adenocarcinoma of the rectosigmoid colon was identified and the patient was managed successfully. Similar to necrotizing infections at other anatomical sites, early diagnosis and timely surgical intervention and systemic antimicrobial therapy are mandatory for treating patients with retroperitoneal necrotizing fasciitis.

Lack of retroperitoneal lymphadenopathy predicts survival of patients with metastatic renal cell carcinoma.

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Vasselli, J R; Yang, J C; Linehan, W M; White, D E; Rosenberg, S A; Walther, M M

2001-07-01

Patients with metastatic renal cell carcinoma have a reported 5-year survival of 0% to 20%. The ability to predict which patients would benefit from nephrectomy and interleukin-2 (IL-2) therapy before any treatment is initiated would be useful for maximizing the advantage of therapy and improving the quality of life. A retrospective analysis of the x-rays and charts of patients treated at the National Institutes of Health Surgery Branch between 1985 and 1996, who presented with metastatic renal cancer beyond the locoregional area and the primary tumor in place, was performed. Preoperative computerized tomography or magnetic resonance imaging, or radiological reports if no scans were available, were used to obtain an estimate of the volume of retroperitoneal lymphadenopathy. Operative notes were used to evaluate whether all lymphadenopathy was resected or disease left in situ, or if any extrarenal resection, including venacavotomy, was performed. Mean survival rate was calculated from the time of nephrectomy to the time of death or last clinical followup. If patients received IL-2 therapy, the response to treatment was recorded. Mean survival and response rate for IL-2 were compared among patients in 3 separate analyses. Patients without preoperatively detected lymphadenopathy were compared with those with at least 1 cm.3 retroperitoneal lymphadenopathy. Also, the patients who had detectable lymphadenopathy were divided into subgroups consisting of all resected, incompletely resected, unresectable and unknown if all disease was resected. Each subgroup was compared with patients without detectable preoperative lymphadenopathy. Patients with less than were compared to those with greater than 50 cm.3 retroperitoneal lymphadenopathy. Patients undergoing extrarenal resection at nephrectomy (complex surgery) due to direct invasion of the tumor into another intra-abdominal organ were compared with those undergoing radical nephrectomy alone, regardless of lymph node status

Image-guided fine needle cytology with aspiration versus non-aspiration in retroperitoneal masses: is aspiration necessary?

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Misra, Rajiv Kumar; Mitra, Shaila; Jain, Rishav Kumar; Vahikar, Shilpa; Bundela, Archana; Misra, Purak

2015-03-01

Although using fine needle cytology with aspiration (FNC-A) for establishing diagnoses in the retroperitoneal region has shown promise, there is scant literature supporting a role of non-aspiration cytology (FNC-NA) for this region. We assessed the accuracy and reliability of FNC-A and FNC-NA as tools for preoperative diagnosis of retroperitoneal masses and compared the results of both techniques with each other and with histopathology. Fifty-seven patients with retroperitoneal masses were subjected to FNC-A and FNC-NA. Smears were stained with May-Grunwald Giemsa and hematoxylin and eosin stain. An individual slide was objectively analysed using a point scoring system to enable comparison between FNC-A and FNC-NA. By FNC-A, 91.7% accuracy was obtained in cases of retroperitoneal lymph node lesions followed by renal masses (83.3%). The diagnostic accuracy of other sites by FNC-A varied from 75.0%-81.9%. By FNC-NA, 93.4% diagnostically accurate results were obtained in the kidney, followed by 75.0% in adrenal masses. The diagnostic accuracy of other sites by FNC-NA varied from 66.7%-72.8%. Although both techniques have their own advantages and disadvantages, FNC-NA may be a more efficient adjuvant method of sampling in retroperitoneal lesions.

Contrast-enhanced 18F-fluorodeoxyglucose positron emission tomography/computed tomography in immunoglobulin G4-related retroperitoneal fibrosis

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Sharma, Punit; Chatterjee, Piyali

2015-01-01

Immunoglobulin G4 (IgG4)-related disease encompasses a wide variety of immune disorders previously thought be distinct. IgG4-related retroperitoneal fibrosis is one such entity. Metabolic imaging with 18 F-fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/computed tomography (PET/CT) can be useful in the management of IgG4-related retroperitoneal fibrosis. We here discuss the case of 63-year-old male with IgG4-related retroperitoneal fibrosis and the role, 18 F-FDG PET/CT played in his management

Atypical olfactory groove meningioma associated with uterine fibromatosis; case report

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Toma I. Papacocea

2016-11-01

Full Text Available The concomitant presence of the olfactory groove meningioma with uterine fibrosis is very rare. Our report presents the case of a giant olfactory groove meningioma revealed after a uterine fibroma resection in a 44 years-old female, due to a generalized seizure 10 days after operation. Cranial CT-scan identified the tumor as an olfactory groove meningioma. The tumor was operated with a macroscopically complete resection; the endothermal coagulation of the dura attachment was performed (Simpson II with a good postoperative evolution. Laboratory results showed the presence of receptors for steroid hormones both in meningioma and uterine tumor, and the histopathological examination revealed an atypical meningioma with 17% proliferation markers. Our findings suggest that even though meningiomas are benign tumors and a complete resection usually indicates a good prognosis, the association with uterine fibromatosis and the presence of high percentage of steroid receptors creates a higher risk to relapse, imposing therefore a good monitoring.

[Retroperitoneal lymphadenectomy and disorders of ejaculation].

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Deiana, G; Ranieri, A; Micheli, E; Peracchia, G; Canclini, L P; Sironi, D; Levorato, C A; Lembo, A

1999-09-01

Retrograde ejaculation is a frequent and permanent complication after bilateral retroperitoneal lymphadenectomy (RPLND). Seminal emission and ejaculation are primarily under sympathetic control. Several studies after RPLND in patients with nonseminomatous testis cancer proved the role of preservation of the efferent fibers originating from the lumbar sympathetic ganglia. Based on the results of anatomical studies, a modified unilateral operative technique and nerve-sparing approach permit to preserve normal anterograde ejaculation without reduction of long-term survival.

Retroperitoneal necrotizing fasciitis presenting with peritonism in a 33-year-old Nepalese man: a case report

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Giri Smith

2012-02-01

Full Text Available Abstract Introduction Retroperitoneal necrotizing fasciitis is a rare, fulminant, and potentially lethal complication of intra-abdominal suppuration. A retroperitoneal origin is very rare and very few cases have been reported in the literature. To the best of our knowledge, this case is only the fourth case reported of successful management following retroperitoneal necrotizing fasciitis. Case presentation A 33-year-old Tamang man presented to our facility with a history of five days of fever and vomiting and eight days of severe left loin pain. On examination, he had features of peritonism. A laparotomy was performed, revealing extensive necrotizing fasciitis of the retroperitoneum extending to the anterior abdominal wall. Our patient survived following extensive debridement of the necrotic tissues and supportive care. Conclusions Retroperitoneal necrotizing fasciitis can rarely present with features of peritonism, and hence should be included as a possible differential diagnosis for anyone presenting with peritonism. Although a fatal condition, early intervention and aggressive management can save the life of a patient.

Retroperitoneal and rectus sheath hematomas.

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Kasotakis, George

2014-02-01

The retroperitoneum is rich in vascular structures and can harbor large hematomas, traumatic or spontaneous. The management of retroperitoneal hematomas depends on the mechanism of injury and whether they are pulsatile/expanding. Rectus sheath hematomas are uncommon abdominal wall hematomas secondary to trauma to the epigastric arteries of the rectus muscle. The common risk factors include anticoagulation, strenuous exercise, coughing, coagulation disorders, and invasive procedures on/through the abdominal wall. The management is largely supportive, with the reversal of anticoagulation and transfusions; angioembolization may be necessary. Copyright © 2014 Elsevier Inc. All rights reserved.

Primary Retroperitoneal Mucinous Cystadenocarcinoma: 5th Male Case in the Literature

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F. Tugba Kos

2015-11-01

Full Text Available Retroperitoneal primary mucinous tumor is an extremely rare malignancy. To date, only 52 cases of primary retroperitoneal mucinous cystadenocarcinoma (PRMC have been reported in the literature, with the majority being women. Our patient is the 5th known male case. A 57-year-old male patient presented with a two year history of an undefined abdominal pain.Computed tomography demonstrated a 12 x 9.5 cm cystic mass lesion extending superiorly from right iliac fossa, while localizing below the abdominal wall and close to the psoas muscle. According to the laparotomy, iliopsoas muscle was infiltrated by the mass in the retroperitoneal region. Pathological diagnosis was mucinous cystadenocarcinoma . The asymptomatic patient was followed up without applying an adjuvant chemotherapy, since the clinical course of the tumor is known to be slow and postoperative therapy is not recognized as a standardized treatment. The clinical course of PRMC is generally indolent, however, it may manifest an aggressive course, as well. It has no definitive and clear pathogenesis. The treatment is contentious, as well. Diagnosis and treatment require surgical excision but data on adjuvant chemotherapy is limited.

Spontaneous Retroperitoneal Hemorrhage from Adrenal Artery Aneurysm

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Gonzalez Valverde, F.M.; Balsalobre, M.; Torregrosa, N.; Molto, M.; Gomez Ramos, M.J.; Vazquez Rojas, J.L.

2007-01-01

Spontaneous adrenal hemorrhage is a very rare but serious disorder of the adrenal gland that can require emergent treatment. We report on a 42-year-old man who underwent selective angiography for diagnosis and treatment of retroperitoneal hemorrhage from small adrenal artery aneurysm. This case gives further details about the value of transluminal artery embolization in the management of visceral aneurysm rupture

A rare case of Riedel's thyroiditis, 6 years after retroperitoneal fibrosis: two diseases with one pathogenesis?

NARCIS (Netherlands)

de Boer, W. A.; van Coevorden, F.; Wiersinga, W. M.

1992-01-01

We describe a 70-yr-old female patient in whom both a retroperitoneal fibrosis and 6 years later a Riedel's thyroiditis were diagnosed. Both diseases belong to the group of fibrotic diseases called "multifocal fibrosis". Retroperitoneal fibrosis is now known to be an auto-allergic reaction to lipid

Retroperitoneal laparoscopic dismembered pyeloplasty with a novel technique of JJ stenting in children.

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Yu, Jianhua; Wu, Zhonghua; Xu, Youming; Li, Zhuo; Wang, Jiansong; Qi, Fan; Chen, Xiang

2011-09-01

• To report our experience with retroperitoneal laparoscopic dismembered pyeloplasty for pelvi-ureteric junction (PUJ) obstruction in children. • Between March 2007 and December 2009, 38 children with PUJ obstruction (mean age 8.3 years, range 3-14) underwent retroperitoneal laparoscopic dismembered pyeloplasty. • A ureteric catheter was inserted into the mid-ureter cystoscopically. During pyeloplasty, the proximal end of the ureteric catheter was extracorporeally sutured to the distal end of the JJ stent with silk. • The ureteric catheter was then pulled down and the stent was pulled antegrade into the ureter and bladder. • The approach was retroperitoneal in all patients except one who required open conversion. The overall mean operative time was 162 min (range 145-210 min) and this appeared to decrease with experience. Mean hospital stay was 4 days (range 3-7 days). • Mean follow-up was 20.2 months (range 6-32 months). Satisfactory drainage with decreased hydronephrosis was documented in all patients on ultrasonography and intravenous urography. • Our study shows that retroperitoneal laparoscopic dismembered pyeloplasty is a feasible and effective alternative to open pyeloplasty with a relatively minimal complication rate in children 3 years of age and older, but it should be undertaken by experienced laparoscopic surgeons. © 2011 THE AUTHORS. BJU INTERNATIONAL © 2011 BJU INTERNATIONAL.

IVC filter limb penetration of the caval wall during retroperitoneal surgery/lymph node dissection.

LENUS (Irish Health Repository)

Goh, Gerard S

2012-12-01

Optional inferior vena cava (IVC) filters are being increasingly used for protection against pulmonary embolism in patients with deep vein thrombosis where anticoagulation is contraindicated. We describe two cases during retroperitoneal surgery where the IVC filters were found to have perforated the cava wall and were subsequently removed intra-operatively. Cava wall penetration by filter limbs poses a significant danger during retroperitoneal lymph node dissection and filters should be removed preoperatively.

Adrenal Hemangioma: A Case of Retroperitoneal Tumor

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Genta Iwamoto

2018-01-01

Full Text Available Introduction. Adrenal hemangioma is a rare disease, with only some 60 cases reported previously. Due to the difficulty of the preoperative diagnosis of adrenal hemangioma, almost all of the cases were diagnosed by a histopathological analysis of surgical specimens. Case Presentation. A 52-year-old man was referred to our department for further examination of his left retroperitoneal tumor. He had received hemodialysis due to chronic renal failure resulting from membranous nephropathy. Computed tomography revealed a mass around his left hilum. Magnetic resonance imaging (MRI and positron-emission tomography (PET-CT were unable to confirm or deny malignancy, and tumor markers, including CEA and CA19-9, showed slight elevation. His tumor grew from 38 mm to 54 mm in diameter in 7 months of follow-up. We therefore planned retroperitoneal tumor resection with left nephrectomy. Histopathologically, hyperplastic small vessels with hemorrhaging and denaturation were seen. The endothelial cells showed no variants or division of the nucleus. Based on this diagnosis, no further therapy was performed. He has had no recurrence in the eight months since the surgery. Conclusion. We herein report a rare case of adrenal hemangioma.

Kidney fibroxanthoma (malignant fibrous xanthoma): a rare tumor and an unusual cause of retroperitoneal hemorrhage.

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Witz, M; Bernheim, J; Dinbar, A; Griffel, B

1984-06-01

A case of kidney fibroxanthoma (malignant fibrous xanthoma, malignant variant of xanthogranuloma), a rare malignant neoplasm of kidney, is described. In addition to the typical histologic features of retroperitoneal xanthogranuloma, this tumor showed obvious pleomorphism and mitotic activity of the histiocytes. We present this case in view of the rarity of this neoplasm and the unusual presentation as massive retroperitoneal hemorrhage.

Acute gaseous peritonitis after rupture of a retroperitoneal rectal diverticulum in a dog.

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Saulnier-Troff, F G; De Busscher, V; Hamaide, A

2008-07-01

An 11-year-old, entire male coton de tulear was presented on emergency with acute and severe depression, acute abdominal pain and vomiting of 24 hours duration. Historical complaints included right perineal swelling, dyschezia and tenesmus of 18 months duration. Abdominal ultrasonography and radiography suggested a pneumoperitoneum and positive-contrast colonography showed leakage of contrast medium into the caudal abdomen and the presence of a large retroperitoneal pouch. Exploratory laparotomy allowed the visualisation of faecal leakage from the retroperitoneal space into the peritoneal cavity. Using a perineal approach, a large necrotised rectal diverticulum filled with faeces was found over the retroperitoneal structures. A standard herniorrhaphy was then performed. The dog recovered uneventfully and dyschezia did not recur at the nine month follow-up. Rectal diverticulum rupture associated with peritonitis has not been described in the veterinary literature, to the authors' knowledge, and should be considered as a rare differential diagnosis in dogs being presented with gaseous peritonitis.

Retroperitoneal disorders associated with IgG4-related autoimmune pancreatitis

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Hara, Noboru; Kawaguchi, Makoto; Takeda, Keisuke; Zen, Yoh

2014-01-01

IgG4-related autoimmune pancreatitis is frequently accompanied by relevant lesions in the genitourinary tract and retroperitoneal organs, which cause various clinical problems, ranging from non-specific back pain or bladder outlet obstruction to renal failure. The diagnosis of IgG4-related retroperitoneal fibrosis requires a multidisciplinary approach, including serological tests, histological examination, imaging analysis, and susceptibility to steroid therapy. Radiological examinations are helpful to diagnose this condition, but surgical resection is occasionally unavoidable to exclude malignancy, particularly for patients with isolated retroperitoneal involvement. Steroid therapy is the treatment of choice for this condition, the same as for other manifestations of IgG4-related disease. For patients with severe ureteral obstruction, additional ureteral stenting needs to be considered prior to steroid therapy to preserve the renal function. Some papers have suggested that IgG4-related disease can affect male reproductive organs including the prostate and testis. IgG4-related prostatitis usually causes lower urinary tract symptoms, such as dysuria and pollakisuria. Patients sometimes state that corticosteroids given for IgG4-related disease at other sites relieve their lower urinary tract symptoms, which leads us to suspect prostatic involvement in this condition. Because of the limited number of publications available, further studies are warranted to better characterize IgG4-related disease in male reproductive organs. PMID:25469023

Retroperitoneal unicentric Castleman's disease (giant lymph node hyperplasia: case report

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Jaques Waisberg

Full Text Available CONTEXT AND OBJECTIVE: Castleman's disease, or giant lymph node hyperplasia, is a rare disorder of the lymphoid tissue that causes lymph node enlargement. It is considered benign in its localized form, but aggressive in the multicentric type. The definitive diagnosis is based on postoperative pathological findings. The aim here was to describe a case of retroperitoneal unicentric Castleman's disease in the retroperitoneum. CASE REPORT: A 61-year old white male with weight loss and listlessness presented with moderate arterial hypertension and leukopenia. Abdominal tomography revealed a 5 x 4 x 5 cm oval mass of low attenuation, with inner calcification and intense enhancement on intravenous contrast, located in the retroperitoneal region, between the left kidney and the aorta, at the renal hilus. Exploratory laparotomy revealed a non-pulsatile solid oval mass situated in the retroperitoneum, adjacent to the left renal hilus. The retroperitoneal lesion was removed in its entirety. Examination of frozen samples revealed benign lymph node tissue and histopathological examination of the surgical sample revealed hyaline-vascular giant lymph node hyperplasia (Castleman's disease. The patient was discharged on the 12th day without significant events. Two months after the operation, the patient was readmitted with severe cardiac insufficiency, acute renal failure and bronchopneumonia, which progressed to acute respiratory insufficiency, sepsis and death.

Chryseobacterium meningosepticum Sepsis Complicated with Retroperitoneal Hematoma and Pleural Effusion in a Diabetic Patient

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Shou-Wu Lee

2008-09-01

Full Text Available Intra-abdominal infection due to Chryseobacterium meningosepticum is rare, and bacteremia complicated with pleural effusion and retroperitoneal hematoma caused by C. meningosepticum has not been reported previously. A 57-year-old diabetic man presented with bacteremia with retroperitoneal abscess and pleural effusion caused by C. meningosepticum on the 12th day of hospitalization. His clinical condition improved after antimicrobial therapy with levofloxacin and rifampin, debridement of the retroperitoneal hematoma and left-side chest tube insertion. Antibiotics were administered for 1 month, and he was later transferred to a local respiratory care ward under afebrile condition. C. meningosepticum should be included in the list of suspected nosocomial infections, especially in patients with immunocompromised status. Administration of appropriate antibiotics, such as quinolone, minocycline, trimethoprim-sulfamethoxazole or rifampin, and treatment of local infection improve the clinical outcome of patients with C. meningosepticum infection.

Endoscopic techniques for diagnosis and correction of complications after retroperitoneal pancreas transplantation

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A. V. Pinchuk

2016-01-01

Full Text Available Relevance. Timely diagnosis and treatment of postoperative complications after pancreas transplantation is an actual problem of modern clinical transplantation. Purpose. The assessment of the endoscopy potential for the diagnosis and correction of postoperative complications after pancreas transplantation. Materials and methods. Since October 2011, simultaneous retroperitoneal pancreas-kidney transplantation has been performed in 27 patients. In 8 cases, the use of endoscopic techniques allowed a timely identification and treatment of the complications occurred. Conclusions. Endoscopic techniques proved to be highly efficient in the diagnosis and treatment of surgical complications and immunological impairments after retroperitoneal pancreas transplantation. 

Retroperitoneal hematoma following rofecoxib and enoxaparin coadministration in a patient with atrial fibrillation

International Nuclear Information System (INIS)

Khan, Fahmi Y.; Hassan, Ibrahim F.; Allity, Mustafa H.; Khan, Saifatullah M.

2005-01-01

There are very few published reports implicating enoxaparin as a factor in retroperitoneal hematoma. We report a patient who developed a retroperitoneal hematoma after using enoxaparin for paroxysmal atrial fibrillation. A 72 year old man was admitted with a history of low back pain, radiating beyond the back to the buttocks. His medical history was positive for bilateral knee osteoarthritis. On his physical examination his vital signs were: temperature 36.8, blood pressure 100/70 mm Hg, pulse 72/min, respiratory rate 16/min. X-ray of both the knees showed bilateral osteoarthritic changes. Computerized tomography scan of the spine showed lumbar spinal stenosis and he was referred to a Neurosurgeon, who finds the patient not fit surgical intervention. ECG showed atrial fibrillation. He was given enoxaparin one mg/kg every 12 hour and digoxin. Abdominal computed tomography revealed a right retroperitoneal hematoma and no aortic aneurysm was noted and enoxaparin and rofecoxib were discontinued. His general condition improved. The factors that increase the risk of bleeding in patients receiving enoxaparin are use of high doses of enxaparin, advanced stage, renal impairment, and the concomitant use of drugs affecting hemostasis. Retroperotoneal hematoma should be considered in the different diagnosis in patients receiving enoxaparin and experiencing unexplained decreases in hemoglobin and hematocrit. In the order of precedence of radiologic diagnostic procedures for fast diagnosis of a retroperitoneal hematoma, abdominal CT-scan is the preferred method

Radiation therapy in retroperitoneal sarcoma management.

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Haas, Rick L; Baldini, Elizabeth H; Chung, Peter W; van Coevorden, Frits; DeLaney, Thomas F

2018-01-01

Surgery is potentially curative for primary non-metastatic retroperitoneal soft tissue sarcomas (RPS), although patients remain at risk for local recurrence. To reduce this risk, the addition of radiotherapy to radical surgery may be considered. Nevertheless, level I evidence to support radiotherapy is currently lacking. The results from the EORTC-STBSG 62092-22092 studying this question are awaited. This manuscript addresses issues to consider when radiation-oncologists engage in a multidisciplinary treatment approach for RPS patients, including radiotherapy. © 2017 Wiley Periodicals, Inc.

Haemoperitoneurn Secondary to Rupture of Retroperitoneal Variceal

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M. Molina-Perez

1997-01-01

Full Text Available A 45-year-old alcoholic male patient presented with hypovolemic shock and intense anemia (Hemoglobin 04.7 g/dl, and was operated on. A bleeding retroperitoneal varix located near the right colon was responsible for the clinical picture and was sutured. After operation the patient developed haemodynamic instability and pneumonia a situation which was reverted with intensive medical therapy. The patient is now doing well.

Clinical significance of peritoneal and retroperitoneal edema in patients with de-compensated cirrhosis as demonstrated by CT scan

International Nuclear Information System (INIS)

Xue Yanshan; Wang Jun; Wang Xinwen

2002-01-01

Objective: To investigate the clinical significance of peritoneal and retroperitoneal edema in patients with de-compensated cirrhosis (DCC). Methods: Forty-four patients, were identified with DCC on the basis of clinic and laboratory examinations, except the cases with mesenteric, omental and retroperitoneal edema caused by inflammatory and malignant diseases. The diagnosis of edema depended upon hyper-density in peritoneal and retroperitoneal. The degree of edema was divided into minor, middle, and sever types based on the extent of edema. Ascites, varices, serum albumin (ALB) levels, and hyaluronic acid (HA) levels were also documented. Correlations between the laboratory and CT findings were analyzed. Results: The severity of peritoneal edema was correlated with decreasing serum ALB (r s = 0.7088, P s = 0.5294, P s = 0.5440, P s = 0.1335, P > 0.05). Conclusion: CT findings of the edema in peritoneal and retroperitoneal may indicate the severity of the liver cirrhosis

Retroperitoneal fibrosis: A rare cause of both ureteral and small bowel obstruction

Institute of Scientific and Technical Information of China (English)

Faisal Aziz; Srinivasulu Conjeevaram; Than Phan

2006-01-01

Retroperitoneal fibrosis (RPF) is a rare condition of unclear etiology. It can cause ureteral obstruction. We present the unique case of a 54 years old female, who initially presented with spontaneous perforation of the cecum. Upon exploring the abdomen, the classical glistening white, unyielding retroperitoneal fibrosis was encountered. A right hemicolectomy was performed.Subsequently, the patient presented with bilateral ureteral obstruction, and later on with small bowel obstruction. Ureteral obstruction was treated with stents,and small bowel obstruction was treated with bypass.To our knowledge no case of idiopathic RPF presenting with features of both bilateral ureteral and small bowel obstruction has been reported in the literature.

Primary retroperitoneal teratoma and crossed fused renal ectopia with turner's syndrome -a case report-

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Kim, Yun Jung; Hong, Ki Ung [St. Francisco General Hospital, New York (United States)

1988-02-15

In 1938, Turner described a clinical entity in phenotype females characterized by sexual infantilism, congenital webbed neck and cubitus valgus. After then, the occurrence of renal anomalies in patients with Turner's syndrome has been recognized. Associated crossed fused renal ectopia is very rare. Primary retroperitoneal teratoma is also rare and usually during childhood. The authors report a case of primary retroperitoneal teratoma and crossed fused renal ectopia with Turner's syndrome (mosaic type). The clinical, pathological and radiographical findings are reviewed.

Primary retroperitoneal teratoma and crossed fused renal ectopia with turner's syndrome -a case report-

International Nuclear Information System (INIS)

Kim, Yun Jung; Hong, Ki Ung

1988-01-01

In 1938, Turner described a clinical entity in phenotype females characterized by sexual infantilism, congenital webbed neck and cubitus valgus. After then, the occurrence of renal anomalies in patients with Turner's syndrome has been recognized. Associated crossed fused renal ectopia is very rare. Primary retroperitoneal teratoma is also rare and usually during childhood. The authors report a case of primary retroperitoneal teratoma and crossed fused renal ectopia with Turner's syndrome (mosaic type). The clinical, pathological and radiographical findings are reviewed

Can the MRI signal of aggressive fibromatosis be used to predict its behavior?

International Nuclear Information System (INIS)

Castellazzi, G.; Vanel, D.; Le Cesne, A.; Le Pechoux, C.; Caillet, H.; Perona, F.; Bonvalot, S.

2009-01-01

Purpose: Aggressive fibromatosis is an invasive non-metastasizing soft-tissue tumor. Until recently, the standard treatment combined surgery and radiation therapy, but new studies reported that conservative strategies with or without medical treatment could be the best management. The aim of this study was to analyze and correlate the size and MR imaging signal features of aggressive fibromatosis with its behavior in order to choose the best treatment. Materials and methods: Between March 1985 and December 2005, 27 patients with at least 2 consecutive MRI examinations and no surgery or radiation therapy in between were recorded. There were 9 men and 18 women, and median age was 31 years. They underwent 107 MRI examinations of 47 lesions, 29 of which were medically treated, while the remaining 18 did not receive any drug administration. The size and signal changes of each lesion were studied over time on T2- and/or T1-weighted sequences after injection of contrast medium. RECIST criteria were used for size: only a 30% decrease or a 20% increase in the size of the main dimension was considered significant. We classified the appearance of the signal into six categories in order of increasing intensity and then we established the related variations over time. Results: The size of 79% of the lesions in the treated group and 82% in the untreated group remained stable. The initial signal of stable lesions or those exhibiting an increase in size was most frequently high. There was a high rate of signal stability over time, whatever the initial signal and size changes. Changes in size were not correlated with the initial MR signal. A decrease in size associated with a decreased signal was observed in three cases exclusively in the treated group. Conclusion: Fibromatoses are a group of soft-tissue tumors with variable characteristics on MRI, but it is not possible to predict their behavior based on the MRI signal

Acute retroperitoneal bleeding due to inferior mesenteric artery aneurysm: Case report

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Ferrón JA

2010-06-01

Full Text Available Abstract Background Visceral artery aneurysms (VAA, although uncommon, are increasingly being detected. We describe a case of spontaneous retroperitoneal hemorrhage from a ruptured IMA aneurysm associated with stenosis of the superior mesenteric artery (SMA and celiac trunk, successfully treated with surgery. Methods A 65-year-old man presented with abdominal pain and hypovolemic shock. Abdominal CT scan showed an aneurysm of the inferior mesenteric artery with retroperitoneal hematoma. In addition, an obstructive disease of the superior mesenteric artery and celiac axis was observed. Results Upon emergency laparotomy a ruptured inferior mesenteric artery aneurysm was detected. The aneurysm was excised and the artery reconstructed by end-to-end anastomosis. Conclusions This report discusses the etiology, presentation, diagnosis and case management of inferior mesenteric artery aneurysms.

Transperitoneal versus retroperitoneal approach for open abdominal aortic aneurysm repair in the targeted vascular National Surgical Quality Improvement Program

NARCIS (Netherlands)

Buck, Dominique B.; Ultee, Klaas H J; Zettervall, Sara L.; Soden, Pete A.; Darling, Jeremy; Wyers, Mark; van Herwaarden, Joost A.; Schermerhorn, Marc L.

Objective: We sought to compare current practices in patient selection and 30-day outcomes for transperitoneal and retroperitoneal abdominal aortic aneurysm (AAA) repairs. Methods: All patients undergoing elective transperitoneal or retroperitoneal surgical repair for AAA between January 2011 and

Intestinal duplication and retroperitoneal teratoma in child hoof: a case report; Duplicacao intestinal e teratoma retroperitoneal na infancia: relato de caso

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Atzingen, Augusto Castelli Von; Bazzano, Felix Carlos Ocariz; Tiburzio, Nicolas Biagione; Grande, Rogerio Mendes; Juntolli Netto, Joao Diniz [Universidade do Vale do Sapucai (UNIVAS), Pouso Alegre, MG (Brazil). Hospital das Clinicas Samuel Libanio (HCSL)]. E-mail: augvonatzingen@bol.com.br; augvonatzingen@hotmail.com

2007-07-01

The authors present a case of intestinal duplication and retroperitoneal teratoma in a 7-year-old patient with evident mass and abdominal pain to explain; that it was submitted to study conventional X-ray, ultrasonography, computed tomography and subsequent exploiting laparotomia. The anatomopathological study verified intestinal duplication and ripe teratoma. In the existent medical literature it was not found any similar case. (author)

Management of metastatic retroperitoneal sarcoma: a consensus approach from the Trans-Atlantic Retroperitoneal Sarcoma Working Group (TARPSWG).

Science.gov (United States)

2018-04-01

Retroperitoneal sarcoma (RPS) is a rare disease accounting for 0.1%-0.2% of all malignancies. Management of RPS is complex and requires multidisciplinary, tailored treatment strategies at all stages, but especially in the context of metastatic or multifocal recurrent disease. Due to the rarity and heterogeneity of this family of diseases, the literature to guide management is limited. The Trans-Atlantic Retroperitoneal Sarcoma Working Group (TARPSWG) is an international collaboration of sarcoma experts from all disciplines convened in an effort to overcome these limitations. The TARPSWG has compiled the available evidence surrounding metastatic and multifocally recurrent RPS along with expert opinion in an iterative process to generate a consensus document regarding the complex management of this disease. The objective of this document is to guide sarcoma specialists from all disciplines in the diagnosis and treatment of multifocal recurrent or metastatic RPS. All aspects of patient assessment, diagnostic processes, local and systemic treatments, and palliation are reviewed in this document, and consensus recommendations provided accordingly. Recommendations were guided by available evidence, in conjunction with expert opinion where evidence was lacking. This consensus document combines the available literature regarding the management of multifocally recurrent or metastastic RPS with the practical expertise of high-volume sarcoma centers from multiple countries. It is designed as a tool for decision making in the complex multidisciplinary management of this condition and is expected to standardize management across centers, thereby ensuring that patients receive the highest quality care.

Agressive fibromatosis involving the mandible--case report and review of the literature.

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Seper, László; Bürger, Horst; Vormoor, Josef; Joos, Ulrich; Kleinheinz, Johannes

2005-01-01

Aggressive fibromatosis (AF) involving the mandible is rare, and surgery is often complicated by a high recurrence rate. A 4-year-old boy was referred because of a fast growing painless mass which involved the entire left angle of the mandible. Excisional biopsy revealed AF, and local excision of the tumor was performed. Six months after surgery a recurrence was detected. The tumor was determined to be unresectable and the boy was treated with low-dose chemotherapy including methotrexate and vinblastine for 1 year. With combined chemotherapy and surgical debulking, mutilating surgical resection will be delayed as long as possible or until completion of facial growth. According to the literature, surgery is the most common treatment of AF in the head and neck region. However, particularly in children, alternative modes of therapy must be considered because of the high recurrence rate and to avoid mutilating operations.

Castleman's disease imitating adrenal mass in the retroperitoneal area.

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Koç, Gökhan; Turk, Hakan; Un, Sıtkı; Isoglu, Cemal Selcuk; Zorlu, Ferruh

2015-01-01

Castleman's disease (CD) is a non-clonal lymph node hyperplasia, mostly seen in the mediastinum. It has various clinical and pathological outcomes. There are different treatments because of its rare occurance and heterogenity. We present 2 cases which were referred to our clinic as retroperitoneal mass and diagnosed as CD after surgical resection.

Nonpalpable testicular pure seminoma with elevated serum alpha-fetoprotein presenting with retroperitoneal metastasis: a case report.

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Iwatsuki, Shoichiro; Naiki, Taku; Kawai, Noriyasu; Etani, Toshiki; Iida, Keitaro; Ando, Ryosuke; Nagai, Takashi; Okada, Atsushi; Tozawa, Keiichi; Sugiyama, Yosuke; Yasui, Takahiro

2016-05-05

Patients with a primary pure seminoma in the testis who have elevated serum alpha-fetoprotein are rare and should be treated as patients with nonseminomatous germ cell tumors. However, nonpalpable testicular tumors in this condition have never been reported. We describe a case of nonpalpable pure testicular seminoma with elevated serum alpha-fetoprotein presenting retroperitoneal metastasis. A 29-year-old Asian man was referred to our hospital with right flank pain. Computed tomography showed a mass located between his aorta and inferior vena cava, but a testicular tumor was not detected. His serum levels of lactate dehydrogenase, alpha-fetoprotein, and DUPAN-2 were high. Although no tumor or nodule was palpable in his testis, ultrasonography revealed multiple low echoic lesions in his right testicular parenchyma. He was diagnosed with right testicular cancer with retroperitoneal lymph node metastasis and underwent right high orchiectomy. A pathological examination revealed pure seminoma and no nonseminomatous components were found in the specimen. Three courses of induction systemic chemotherapy (cisplatin, etoposide, and bleomycin) normalized his serum alpha-fetoprotein and DUPAN-2 levels. Three additional courses of chemotherapy (etoposide and bleomycin) were performed, and treatment was completed with laparoscopic retroperitoneal lymph node dissection. Pathology of the dissected specimen showed fibrous and necrotic tissue with no viable cells. He is alive without recurrence 54 months after orchiectomy. We report a case of pure testicular seminoma with elevated serum alpha-fetoprotein and DUPAN-2 presenting retroperitoneal metastasis. We recommend an ultrasound examination of bilateral testes when large retroperitoneal tumors are detected in young men, even if a mass is not palpable in the scrotum.

[Desmoid fibromatosis in absorption infrared spectroscopy, emission spectral analysis and roentgen diffraction recording].

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Zejkan, A; Bejcek, Z; Horejs, J; Vrbová, H; Bakosová, M; Macholda, F; Rykl, D

1989-10-01

The authors present results of serial quality and quantity microanalyses of bone patterns and dental tissue patterns in patient with desmoid fibromatosis. Methods of absorption spectroscopy, emission spectral analysis and X-ray diffraction analysis with follow-up to x-ray examination are tested. The above mentioned methods function in a on-line system by means of specially adjusted monitor unit which is controlled centrally by the computer processor system. The whole process of measurement is fully automated and the data obtained are recorded processed in the unit data structure classified into index sequence blocks of data. Serial microanalyses offer exact data for the study of structural changes of dental and bone tissues which manifest themselves in order of crystal grid shifts. They prove the fact that microanalyses give new possibilities in detection and interpretation of chemical and structural changes of apatite cell.

Medial arcuate ligament: a new anatomic landmark facilitates the location of the renal artery in retroperitoneal laparoscopic renal surgery.

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Cai, Wei; Li, Hong Zhao; Zhang, Xu; Song, Yong; Ma, Xin; Dong, Jun; Chen, Wenzheng; Chen, Guang-Fu; Xu, Yong; Lu, Jin Shan; Wang, Bao-Jun; Shi, Tao-Ping

2013-01-01

The purpose of this study was to introduce a new method for locating the renal artery during retroperitoneal laparoscopic renal surgery. The medial arcuate ligament (MAL) is a tendinous arch in the fascia under the diaphragm that arches across the psoas major muscle and is attached medially to the side of the first or the second lumbar vertebra. The renal artery arises at the level of the intervertebral disc between the L1 and L2 vertebrae. We evaluate the role of the MAL that serves as an anatomic landmark for locating the renal artery during retroperitoneal laparoscopic renal surgery. There is a reproducible consistent anatomic relationship between MAL and the renal artery in 210 cases of retroperitoneal laparoscopic renal surgery. Two main types of the MAL, the "narrow arch" and the "fascial band" types, can be observed. MAL can serve as an accurate and reproducible anatomic landmark for the identification of the renal artery during retroperitoneal laparoscopic renal surgery.

Retroperitoneal Malignant Peripheral Nerve Sheath Tumour: A Rare Case Report.

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Deger, Ayse Nur; Bayar, Mehmet Akif; Caydere, Muzaffer; Deger, Hakki; Tayfur, Mahir

2015-09-01

Malignant nerve sheath tumours (MPNST) are rare neoplasias and retroperitoneal cases are fairly rare and clinically difficult to be detected, but they are very agressive neoplasias. MPNST are frequently seen in head, neck and upper extremities. In patients with NF1; MPNST, a poor-prognostic lesion, may result from a malignant degeneration of a former plexiform neurofibroma. It is necessary to be aware of a potential malignancy in patients diagnosed with plexiform neurofibroma. We present a 21-year-old female with a diagnosis of MPNST. The patient was admited to the hospital because of a tumour in the subcutaneous region on her left buttock. The surgeon's clinical diagnosis was lipoma. After the pathological examination of biopsy specimen, the lesion was identified as "plexiform neurofibroma" and then the patient was diagnosed with Neurofibromatosis Type 1 (NF1). Simultaneously, another mass on the retroperitoneal region was identified as malignant peripheral nerve sheath tumour (MPNST).

EUS-FNA for the Diagnosis of Retroperitoneal Primitive Neuroectodermal Tumor

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Aijaz A. Sofi

2011-01-01

Full Text Available Primitive neuroectodermal tumor (PNET is a rare “small round blue cell tumor” that is diagnosed by open biopsy or percutaneous biopsy of the lesion under radiologic guidance. In this case report, we present a novel approach to the diagnosis of a retroperitoneal PNET by endoscopic ultrasound- (EUS- guided fine needle aspiration (FNA. A 35-year-old man presented with the history of left-sided flank pain and swelling of 3-weeks duration. Computerized tomography (CT scan of his abdomen revealed a 12.8 × 13 × 12.5 cm cystic and solid mass arising from the retroperitoneum and displacing the third and fourth portions of the duodenum. He underwent EUS which revealed a well-circumscribed heterogeneous mass abutting the inferior portion of the stomach. EUS-FNA of the mass revealed malignant cells consistent with primitive neuroectodermal tumor (PNET/Ewing's sarcoma. EUS-guided FNA is an appropriate technique for diagnosing retroperitoneal PNET/Ewing's sarcoma.

Leiomyosarcoma, embrionary rhabdomyosarcoma and malignant peripheral nerve sheath tumor: report of three cases of atypical retroperitoneal sarcomas

International Nuclear Information System (INIS)

Catalan, Julian; Justino Junior, Reinaldo Ottero; Tjioe Tjia Min; Lima, Ana Carolina Mori; Fonte, Alexandre Calabria da; Goncalves, Carlos Marcelo

2005-01-01

We report three cases of atypical retroperitoneal sarcomas: leiomyosarcoma, embrionary rhabdomyosarcoma and malignant peripheral nerve sheath tumor (previously known as neuro sarcoma and neuro fibrosarcoma). These lesions, which are characterized by large and heterogeneous retroperitoneal masses, are uncommon and usually diagnosed late. Intravenous contrast enhanced computerized tomography is a useful method for the evaluation of these tumors and their relationship with adjacent structures. (author)

The role of CT in pelvic fracture. CT finding of retro-peritoneal hematoma and indication of transcatheter arterial embolization

International Nuclear Information System (INIS)

Igarashi, Tsuneo; Hoshikawa, Yoshikazu; Saeki, Mitsuaki; Nakajima, Yasuo

1998-01-01

Although retro-peritoneal hematoma accompanying a pelvic fracture has been treated by arterial ligation formerly, it is associated with a high mortality rate and a transcatheter arterial embolization has now become the first choice of treatment. Meanwhile, the usefulness of computed tomography (CT) in traumatized patient has been reported frequently. Our hospital also employs CT positively as an examination following plain radiography in the cases with pelvic fracture. However, while indication of angiography is seen in several reports, the amount of retro-peritoneal hematoma as an index has not been reported. In the present study, we examined 112 patients given CT at the time of examination at the emergency center of our hospital between April 1, 1988, and June 30, 1997, and classified the amount of retro-peritoneal hematoma on CT into 5 groups to discuss indication of angiography. In the cases with moderate or massive amount of retro-peritoneal hematomas, cases with shock state exceeded 60% and the amount of hematoma was considered to reflect the circulation profile to a certain extent. As the amount of retro-peritoneal hematoma increased, the number of cases given embolization also increased; embolization was performed in 29 cases (61.7%) among those which had moderate or massive amount of hematoma. From the above findings, it was predicted that the amount of retro-peritoneal hematoma could be one of the deciding factors for indication of angiography. However, as there are cases falling into a shock state due to gradual increase of hematoma or associated with injuries in other organs, careful observation is needed for the cases judged out of indication. (author)

Hereditary gingival fibromatosis: A report of two cases in the same family

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Vanali V Umrania

2016-01-01

Full Text Available Overgrowth of keratinized gingival tissues is a common condition and is described under variety of names. Causes of such enlargement can be medications, hereditary, and/or local irritating factors. Mutation in SOS1, son-of-sevenless gene, is thought to be responsible for hereditary gingival fibromatosis. This report shows a case of 19-year-old male and his 15-year-old sister, with a chief complaint of overgrowth of gingival and irregularly placed teeth. A similar overgrowth was also found in other members of the same family, without any drug history or syndromic conditions. An occurrence of the disease has been found in two generations of this family and therefore, it may be following autosomal dominant trait of inheritance. Since it is idiopathic and has a genetic cause for its occurrence, it cannot be prevented. Both cases underwent a surgical intervention to rectify the abnormality and were followed from 6 months to 1 year, during which there was no recurrence.

Ultrastructural evaluation of gingival connective tissue in hereditary gingival fibromatosis.

Science.gov (United States)

Pêgo, Sabina Pena B; de Faria, Paulo Rogério; Santos, Luis Antônio N; Coletta, Ricardo D; de Aquino, Sibele Nascimento; Martelli-Júnior, Hercílio

2016-07-01

To describe the ultrastructural features of hereditary gingival fibromatosis (HGF) in affected family members and compare microscopic findings with normal gingival (NG) tissue. Gingival tissue samples from nine patients with HGF from five unrelated families were evaluated by transmission electron microscopy. Nine NG tissue samples were used for comparison. Areas containing collagen fibrils forming loops and folds were observed in both groups, whereas oxytalan fibers were frequently identified in the HGF group. The diameter of collagen fibrils and the interfibrillar space among them were more uniform in the NG group than in the HGF group. Fibroblasts were the most common cells found in both the HGF and NG groups and exhibited enlarged, rough endoplasmic reticulum, mitochondria with well-preserved crests, conspicuous nucleoli, and euchromatic chromatin. Other cells, such as mast cells, plasma cells, and macrophages, were also observed. HGF tissues had ultrastructural characteristics that were very similar to those of NG tissues. Oxytalan fibers were observed more frequently in the HGF samples than in the NG samples. Other studies of HGF in patients from different families should be performed to better understand the pathogenesis of this hereditary condition. Copyright © 2016 Elsevier Inc. All rights reserved.

Retroperitoneal laparoscopy management for ureteral fibroepithelial polyps causing hydronephrosis in children: a report of five cases.

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Dai, L N; Chen, C D; Lin, X K; Wang, Y B; Xia, L G; Liu, P; Chen, X M; Li, Z R

2015-10-01

Hydronephrosis is a common disease in children and may be caused by ureteral fibroepithelial polyps (UFP). Ureteral fibroepithelial polyps are rare in children and are difficult to precisely diagnose before surgery. Surgical treatment for symptomatic UFP is recommended. At the present institution, retroperitoneal laparoscopy has been used to treat five boys with UFP since 2006. To highlight the significance of UFP as an etiological factor of hydronephrosis in children and evaluate the applicative value of retroperitoneal laparoscopy in the treatment of children with UFP. Between 2006 and 2013 five boys underwent retroperitoneal laparoscopy at the present institution. They were identified with UFP by review of the clinical database. Detailed data were collected, including: radiographic studies, gross anatomical pathology, and pathology and radiology reports. All boys had been followed up at least every 6 months. All of the boys were aged between 7 and 16 years (mean 9.8 years). The main symptoms were flank pain (all five) and hematuria (three). Radiographic examination showed that all of the boys presented with incomplete ureteral obstruction and hydronephrosis. The ureteral fibroepithelial polyps were located near the left UPJ or the left proximal ureter. All of the boys had the UFP removed: three underwent retroperitoneal laparoscopic dismembered Anderson-Hynes pyeloplasty and polypectomy, and two had retroperitoneal laparoscopic ureteral anastomosis. These polyps were all on the left side and between 15 and 35 mm in length (mean 22 mm) (Figure). All of the boys recovered well and were discharged from hospital. The postoperative histological report confirmed that the specimens were UFP. Hydronephrosis was periodically assessed by ultrasonography (using the same method as pre-surgical ultrasonography) after surgery. Mean follow-up was 33 months (range 6-58 months) and no complications were found afterwards. Ureteral fibroepithelial polyps are rare but rather

Clinical Value of CT-Guided Needle Biopsy for Retroperitoneal Lesions

International Nuclear Information System (INIS)

Tomozawa, Yuki; Inaba, Yoshitaka; Yamaura, Hidekazu; Sato, Yozo; Kato, Mina; Kanamoto, Takaaki; Sakane, Makoto

2011-01-01

The purpose of this study was to investigate retrospectively the clinical procedural performance of CT-guided needle biopsy for retroperitoneal lesions. CT-guided needle biopsy was performed in 74 consecutive patients (M:F = 44:30; mean age, 59.7 years) with retroperitoneal lesions between April 1998 and June 2009. The target lesion ranged from 1.5 to 12.5 cm in size. The biopsy access path ranged from 3.5 to 11.5 cm in depth. A biopsy specimen was obtained using an 18-gauge core needle under a CT or CT-fluoroscopy guidance and with the patient under local anesthesia. The histopathological diagnoses from the biopsies were obtained. The diagnostic confirmation of the subtype of lymphoma was evaluated. Satisfactory biopsy samples were obtained in 73 (99%) of 74 patients and a pathological diagnosis was made in 70 (95%) of 74 patients. Sixty three lesions were malignant (45 lymphomas, nine primary tumors, nine lymph node metastases) and seven were benign. The subtype of lymphoma was specified in 43 (96%) of 45 patients who were diagnosed with lymphoma. Analysis of the value of CT-guided biopsy in this series indicated 63 true positives, zero false positive, six true negatives and five false negatives. This test had a sensitivity of 93%, a specificity of 100% and an accuracy of 93%. No major complications were seen and minor complications were noted in seven patients (five with local hematomas, two with transient pain at the puncture site). CT-guided needle biopsy for retroperitoneal lesions is highly practical and useful, and particularly for determining the subtypes in patients with lymphoma.

MR-guided biopsies of lesions in the retroperitoneal space: technique and results

International Nuclear Information System (INIS)

Zangos, S.; Eichler, K.; Wetter, A.; Lehnert, T.; Hammerstingl, R.; Diebold, T.; Reichel, P.; Herzog, C.; Mack, M.G.; Vogl, T.J.; Hansmann, M.-L.

2006-01-01

The purpose of this study was to evaluate the safety and precision of MRI-guided biopsies of retroperitoneal space-occupying tumors in an open low-field system. In 30 patients with indistinct retroperitoneal tumors [paraaortic lesion (n=20), kidney (n=2), suprarenal gland (n=3) and pancreas (n=5)] MR-guided biopsies were performed using a low-field system (0.2 T, Magnetom Concerto, Siemens, Germany). For the monitoring of the biopsies T1-weighted FLASH sequences (TR/TE=160/5 ms; 90 ) were used in all patients and modified FLASH sequences (TR/TE=160/13 ms; 90 ) in ten patients. After positioning of the needle in the tumors 114 biopsy specimens were acquired in coaxial technique with 16-gauge cutting needles (Somatex, Germany). The biopsies were successfully performed in all patients without vascular or organ injuries. The visualization of the aortic blood flow with MRI facilitated the biopsy procedures of paraaortic lesions. The size of the lesions ranged from 1.6 to 7.5 cm. The median distance of the biopsy access path was 10.4 cm. Adequate specimens were obtained in 28 cases (93.3%) resulting in a correct histological classification of 27 lesions (90%). In conclusion, MR-guided biopsies of retroperitoneal lesions using an open low-field system can be performed safely and accurately and is an alternative to CT-guided biopsies. (orig.)

Massive retroperitoneal ganglioneuroma presenting with small bowel obstruction 18 years following initial diagnosis.

LENUS (Irish Health Repository)

Cronin, E M P

2012-02-03

BACKGROUND: Ganglioneuroma is a rare tumour of neural crest origin, which arises from maturation of a neuroblastoma. While previously considered to be non-functioning, they are now known to be frequently endocrinologically active. AIMS AND METHODS: We report a case of a massive retroperitoneal ganglioneuroma presenting with small bowel obstruction in an adult, 18 years after initial diagnosis. Urinary dopamine levels were elevated, but other catecholamines were within normal limits. This is the first report in the English-language literature of a retroperitoneal ganglioneuroma presenting with or causing intestinal obstruction. We also review the metabolic, radiological, and histological features of these tumours. Relevant publications were identified from a Medline search using the MeSH headings \\'ganglioneuroma\\

Amyloidoma of Retroperitoneal Lymph Nodes: A Case Report

International Nuclear Information System (INIS)

Kim, Wee Kyoung; Song, Soon Young; Cho, On Koo; Koh, Byoung Hee; Kim, Yong Soo; Jung, Woo Kyoung; Kim, Min Yeong; Park, Moon Hyang

2011-01-01

Herein we report a case of retroperitoneal amyloidoma in a 56-year-old man and to describe its imaging findings and pathologic features. Abdomen computed tomography showed multiple nodular masses with amorphous calcifications in the retroperitoneum. On histologic review, these masses were composed of extensive nodular deposition of irregularly shaped amorphous eosinophilic material that was strongly positive on Congo red staining and apple green birefringence under polarizing microscopy, which is diagnostic for amyloidosis.

Amyloidoma of Retroperitoneal Lymph Nodes: A Case Report

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Kim, Wee Kyoung; Song, Soon Young; Cho, On Koo; Koh, Byoung Hee [Dept. of Radiology, College of Medicine, Hanyang University, Seoul (Korea, Republic of); Kim, Yong Soo; Jung, Woo Kyoung; Kim, Min Yeong [Dept. of Radiology, College of Medicine, Hanyang University Guri Hospital, Guri (Korea, Republic of); Park, Moon Hyang [Dept. of Pathology, Hanyang University Hospital, College of Medicine, Seoul (Korea, Republic of)

2011-05-15

Herein we report a case of retroperitoneal amyloidoma in a 56-year-old man and to describe its imaging findings and pathologic features. Abdomen computed tomography showed multiple nodular masses with amorphous calcifications in the retroperitoneum. On histologic review, these masses were composed of extensive nodular deposition of irregularly shaped amorphous eosinophilic material that was strongly positive on Congo red staining and apple green birefringence under polarizing microscopy, which is diagnostic for amyloidosis.

Prospective assessment of MRI for imaging retroperitoneal metastases from testicular germ cell tumours

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Sohaib, S.A. [Department of Radiology, Institute of Cancer Research and Royal Marsden Hospital, Sutton, Surrey (United Kingdom)], E-mail: aslam.sohaib@rmh.nhs.uk; Koh, D.M. [Department of Radiology, Institute of Cancer Research and Royal Marsden Hospital, Sutton, Surrey (United Kingdom); Barbachano, Y. [Department of Computing and Statistics, Royal Marsden Hospital, Institute of Cancer Research and Royal Marsden Hospital, Sutton, Surrey (United Kingdom); Parikh, J.; Husband, J.E.S. [Department of Radiology, Institute of Cancer Research and Royal Marsden Hospital, Sutton, Surrey (United Kingdom); Dearnaley, D.P.; Horwich, A.; Huddart, R. [Department of Academic Urology Unit, Institute of Cancer Research and Royal Marsden Hospital, Sutton, Surrey (United Kingdom)

2009-04-15

Aim: To determine the sensitivity of magnetic resonance imaging (MRI) in the detection of retroperitoneal lymph nodes in patients with testicular germ cell tumours (TGCT). Methods and materials: A prospective study of 52 patients (mean age 34 years, range 18-54 years) was performed. Imaging of the retroperitoneum was performed using multidetector computed tomography (CT) and 1.5 T MRI systems. The CT and MRI images were read independently by three observers. The number, size, and site of enlarged nodes ({>=}10 mm maximum short axis diameter) were recorded. Retroperitoneal nodal detection on MRI was compared to CT. Results: Twenty-two (42%) of the 52 patients had no retroperitoneal disease; in remaining 30 patients 51 enlarged nodes were identified. On a per patient basis readers 1, 2, and 3 identified nodal disease in 28 of 29, 29 of 30, and 24 of 30 patients, respectively, using MRI compared to CT. Thus for experienced radiologists (readers 1 and 2) MRI is comparable to CT for nodal detection (i.e., this study excludes MRI being inferior to CT with 80% power and 5% type 1 error). Conclusion: MRI offers an alternative method for staging the retroperitoneum in young patients being followed for TGCT and has the major advantage of avoiding exposure to ionizing radiation.

Retroperitoneal Laparoscopic Partial Nephrectomy Versus Radical Nephrectomy for Clinical T1 Renal Hilar Tumor: Comparison of Perioperative Characteristics and Short-Term Functional and Oncologic Outcomes.

Science.gov (United States)

Yang, Chuance; Wang, Zhenlong; Huang, Shanlong; Xue, Li; Fu, Delai; Chong, Tie

2018-04-18

To present our single-center experience with retroperitoneal laparoscopic partial nephrectomy (LPN) and retroperitoneal laparoscopic radical nephrectomy (LRN) for T1 renal hilar tumors and evaluate which one is better. A retrospective review of 63 patients with hilar tumors undergoing retroperitoneal LPN or LRN was performed. The perioperative characteristics, change in estimated glomerular filtration rate (eGFR) from baseline to month 3, and oncologic outcomes were summarized. In total, 25 patients underwent LPN, and 38 patients underwent LRN. The mean tumor size in the LPN and LRN groups was 4.5 and 4.9 cm, respectively. The mean operation time was longer in the LPN group than that in the LRN group (212.5 minutes versus 160.7 minutes, respectively; P  .05). In experienced hands, although retroperitoneal LRN can result in shorter operation times and shorter lengths of stay, retroperitoneal LPN can preserve renal function better than LRN. Retroperitoneal LPN should be the priority in selected patients with T1 renal hilar tumors, especially for patients with renal insufficiency.

PARAVAGINAL AND RETROPERITONEAL HAEMATOMA POST PARTUM

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Boštjan Lovšin

2018-02-01

Full Text Available Background. Postpartum haemorrhage from ruptured tissues can usually be diagnosed and managed properly. A problem exists with the occult haemorrhage without evident tissue trauma in which case a haematoma develops. Methods. After a normal delivery of the 41 years old secundipara after a previous caesarean in epidural analgesia a boy was born. Placenta was delivered spontaneously and perineal rupure sutured properly. About an hour after the delivery heavy pain was noted in the lower abdomen. Pelvic exam revealed a paravaginal haematoma and ultrasound scan coagulated and fresh blood behind the uterus. Rupture of the uterus was suspected and laparotomy revision performed. During the laparotomy there was no haemorrhage in the pelvic cavity, no uterine rupture but a large retroperitoneal haematoma extending to mesosigmoidal part of intestinum. Paravaginal heamatoma was evacuated vaginally and after half an hour the retroperitoneal haematoma diminished by 50 %. The patient received two blood transfusions. The blood loss was estimated as about 500 grams. The pulse and blood pressure were normal all the time. The laboratory values of haemoglobin was 96 g/l, haematocrit 0.30 before the operation and 93 g/l and 0.28 respectively 6 hours after. Beside anaemia the postoperative course was uneventful and the patient was dismissed from the hospital the 6th day postpartum. Conclusions. Although the laparotomy seems an excessive treatment it was the only way to exclude uterus rupture after a previous caesarean, heavy pain in the lower abdomen and blood behind the uterus noted on the ultrasound scan. In the non-urgent situation a CT scan could be performed to locate the blood accumulation and possibly exclude uterine rupture.

Giant retroperitoneal lipoma: a case report Lipoma gigante do retroperitônio: relato de caso

Directory of Open Access Journals (Sweden)

Carlos Augusto Real Martinez

2003-12-01

Full Text Available BACKGROUND: Retroperitoneal lipoma is an extremely rare neoplasm. AIMS: The authors report a case of giant retroperitoneal lipoma in a 32-year-old white female, with a history of pain and an abdominal mass over a 2-year period. Total abdominal ultrasonography and barium enema showed a large mass located in the retroperitoneal space behind the ascending colon. Laparotomy showed a large encapsulated tumor measuring 20 x 13 x 10 cm and weighing 3.400 g. The histological study revealed a benign neoplasm of fatty cells. CONCLUSION: The patient remains well 17 years after surgery, without recurrentce of the disease.RACIONAL: O lipoma é a neoplasia mesenquimal mais freqüente, raramente localizada no retroperitônio. Na maioria das vezes, o diagnóstico diferencial pré-operatório com os lipossarcomas de baixo grau de malignidade é difícil de ser estabelecido. OBJETIVO: Apresentar um caso de lipoma gigante retroperitoneal em mulher de 32 anos que há 2 anos apresentava história de dor e tumor abdominal palpável. A ultra-sonografia abdominal e o enema opaco mostraram grande massa localizada no retroperitônio, que deslocava o ceco e o cólon ascendente. A laparotomia mostrou tumor encapsulado com 20 x 13 x 10 cm e 3.400 g de peso. O estudo histopatológico mostrou presença de lipoma retroperitonial. A paciente encontra-se bem, sem recidiva da doença, 17 anos após a cirurgia.

Spontaneous resolution of apparent radiation associated retroperitoneal fibrosis.

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Khezri, Azadeh; Berman, Howard L; Rosenstein, Elliot D; Kramer, Neil

2011-12-01

A 70-year-old man was diagnosed with retroperitoneal fibrosis (RPF) complicated by ureteral obstruction 4 months after finishing radiotherapy for prostate cancer. He was treated conservatively with ureteral stent placement. After 3 months, computed tomography scan of the abdomen revealed resolution of RPF without any medical or surgical interventions. Although an uncommon event, the possibility of spontaneous resolution of RPF, as demonstrated by this and previously reported cases, has led some to encourage conservative management.

Preoperative radiation therapy and iododeoxyuridine for large retroperitoneal sarcomas

International Nuclear Information System (INIS)

Robertson, John M.; Sondak, Vernon K.; Weiss, Sharon A.; Sussman, Jeffrey J.; Chang, Alfred E.; Lawrence, Theodore S.

1995-01-01

Purpose: Local failure is frequent after conventional therapy for patients with retroperitoneal sarcomas. A Phase I/II multimodality approach was used, combining iododeoxyuridine (IdUrd) and radiation therapy, followed by attempted surgical resection, with the goal of improving local control. Methods and Materials: Patients with retroperitoneal sarcomas were treated with three to five consecutive cycles of treatment. Each 14-day cycle consisted of a continuous intravenous infusion of IdUrd on days 1-5, twice a day radiation therapy (1.25 Gy/fraction) on days 8-12, and a break on day 13 and 14. Surgical resection was attempted after three or five cycles. Patients resected after three cycles received an additional two cycles of treatment with radiation directed to the tumor bed. IdUrd dose was escalated in Phase I fashion (1000 mg/m 2 /day, 1333 mg/m 2 /day, and 1600 mg/m 2 /day). The median potential follow-up was 31 months. Results: Sixteen patients (13 with high grade tumors) were treated. The median maximum tumor size was 17 cm. Resection margins were negative in four patients, microscopically positive in four patients, and grossly positive in three patients. Five patients were not resected. The only grade 4 acute toxicity observed was vomiting which occurred in three patients receiving upper abdominal radiation. Postsurgical and long-term complications were rare. Median survival overall and for resected patients were 18 and 32 months, respectively. Local control was observed in three out of four patients with negative margins (9, 40+, and 51+ months), two out of four patients with microscopically positive margins (4 and 22 months), and one out of three patients with grossly positive margins (46+ months). The overall freedom from local progression was 45% at 24 months. Conclusion: Retroperitoneal sarcomas can be resected after preoperative radiation therapy and IdUrd, with encouraging local control in patients resected with negative or microscopically positive

Retroperitoneal versus transperitoneal robotic-assisted laparoscopic partial nephrectomy: a matched-pair, bicenter analysis with cost comparison using time-driven activity-based costing.

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Laviana, Aaron A; Tan, Hung-Jui; Hu, Jim C; Weizer, Alon Z; Chang, Sam S; Barocas, Daniel A

2018-03-01

To perform a bicenter, retrospective study of perioperative outcomes of retroperitoneal versus transperitoneal robotic-assisted laparoscopic partial nephrectomy (RALPN) and assess costs using time-driven activity-based costing (TDABC). We identified 355 consecutive patients who underwent RALPN at University of California Los Angeles and the University of Michigan during 2009-2016. We matched according to RENAL nephrometry score, date, and institution for 78 retroperitoneal versus 78 transperitoneal RALPN. Unadjusted analyses were performed using McNemar's Chi-squared or paired t test, and adjusted analyses were performed using multivariable repeated measures regression analysis. From multivariable models, predicted probabilities were derived according to approach. Cost analysis was performed using TDABC. Patients treated with retroperitoneal versus transperitoneal RALPN were similar in age (P = 0.490), sex (P = 0.715), BMI (P = 0.273), and comorbidity (P = 0.393). Most tumors were posterior or lateral in both the retroperitoneal (92.3%) and transperitoneal (85.9%) groups. Retroperitoneal RALPN was associated with shorter operative times (167.0 versus 191.1 min, P = 0.001) and length of stay (LOS) (1.8 versus 2.7 days, P factoring in disposable equipment, operative time, LOS, and personnel. In two high-volume, tertiary centers, retroperitoneal RALPN is associated with reduced operative times and shortened LOS in posterior and lateral tumors, whereas sharing similar clinicopathologic outcomes, which may translate into lower healthcare costs. Further investigation into anterior tumors is needed.

C. T. criteria of the differential diagnosis in primary retroperitoneal masses

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Pistolesi, G.F.; Procacci, C.; Caudana, R.; Bergamo Andreis, I.A.; Manera, V.; Recla, M.; Grasso, G.; Florio, C.

1984-05-01

This personal series of 44 primary retroperitoneal masses (P.R.P.M.) studied by C.T. is analyzed. The reliability of C.T. in the identification (44/44), characterization (43/44) and origin evaluation (41/44) of P.R.P.M. has been absolutely satisfactory. In particular, those criteria of C.T. diagnosis which may be utilized in the evaluation of the origin of upper abdominal masses are thoroughly described. The evaluation of the involvement (non invasive; invasive) of adjacent viscera has been achieved in 22/38 P.R.P.M. verified at operation. The evaluation of tumour resectability has been less reliable due to the high incidence of under-diagnosis (60% in our personal experience). C.T. may be used in addition as an aid to different diagnostic techniques (percutaneous guided needle biopsy) or to therapy (drainage of retroperitoneal abscesses). C.T. is absolutely necessary in the follow-up of P.R.P.M. after surgery, radiotherapy or chemotherapy.

C.T. criteria of the differential diagnosis in primary retroperitoneal masses

International Nuclear Information System (INIS)

Pistolesi, G.F.; Procacci, C.; Caudana, R.; Bergamo Andreis, I.A.; Manera, V.; Recla, M.; Grasso, G.; Florio, C.

1984-01-01

This personal series of 44 primary retroperitoneal masses (P.R.P.M.) studied by C.T. is analyzed. The reliability of C.T. in the identification (44/44), characterization (43/44) and origin evaluation (41/44) of P.R.P.M. has been absolutely satisfactory. In particular, those criteria of C.T. diagnosis which may be utilized in the evaluation of the origin of upper abdominal masses are thoroughly described. The evaluation of the involvement (non invasive; invasive) of adjacent viscera has been achieved in 22/38 P.R.P.M. verified at operation. The evaluation of tumour resectability has been less reliable due to the high incidence of under-diagnosis (60% in our personal experience). C.T. may be used in addition as an aid to different diagnostic techniques (percutaneous guided needle biopsy) or to therapy (drainage of retroperitoneal abscesses). C.T. is absolutely necessary in the follow-up of P.R.P.M. after surgery, radiotherapy or chemotherapy. (orig.)

Lateral retroperitoneal transpsoas interbody fusion in a patient with achondroplastic dwarfism.

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Staub, Blake N; Holman, Paul J

2015-02-01

The authors present the first reported use of the lateral retroperitoneal transpsoas approach for interbody arthrodesis in a patient with achondroplastic dwarfism. The inherent anatomical abnormalities of the spine present in achondroplastic dwarfism predispose these patients to an increased incidence of spinal deformity as well as neurogenic claudication and potential radicular symptoms. The risks associated with prolonged general anesthesia and intolerance of significant blood loss in these patients makes them ideal candidates for minimally invasive spinal surgery. The patient in this case was a 51-year-old man with achondroplastic dwarfism who had a history of progressive claudication and radicular pain despite previous extensive lumbar laminectomies. The lateral retroperitoneal transpsoas approach was used for placement of interbody cages at L1/2, L2/3, L3/4, and L4/5, followed by posterior decompression and pedicle screw instrumentation. The patient tolerated the procedure well with no complications. Postoperatively his claudicatory and radicular symptoms resolved and a CT scan revealed solid arthrodesis with no periimplant lucencies.

Castleman’s disease imitating adrenal mass in the retroperitoneal area

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Koç, Gökhan; Turk, Hakan; Un, Sıtkı; Isoglu, Cemal Selcuk; Zorlu, Ferruh

2015-01-01

Castleman’s disease (CD) is a non-clonal lymph node hyperplasia, mostly seen in the mediastinum. It has various clinical and pathological outcomes. There are different treatments because of its rare occurance and heterogenity. We present 2 cases which were referred to our clinic as retroperitoneal mass and diagnosed as CD after surgical resection. PMID:25624969

Desmoid Fibromatosis of the Abdominal Wall: Surgical Resection and Reconstruction with Biological Matrix Egis®

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Saveria Tropea

2017-02-01

Full Text Available Desmoid tumor is a rare monoclonal fibroblast proliferation that is regarded as benign. The clinical management of desmoid tumors is very complex and requires a multidisciplinary approach because of the unpredictable disease course. For those cases localized in the anterior abdominal wall, symptomatic and unresponsive to medical treatment, radical resection and reconstruction with a prosthetic device are indicated. We present here a case of desmoid fibromatosis of the left anterolateral abdominal wall with a marked increase of the mass that required a large excision followed by reconstruction with biological matrix. The fact that it can be incorporated in patient tissue without a fibrotic response and that it can resist future infections, together with a very competetive price, made the new collagen matrix Egis® our first choice.

Desmoid Fibromatosis of the Abdominal Wall: Surgical Resection and Reconstruction with Biological Matrix Egis®

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Tropea, Saveria; Mocellin, Simone; Stramare, Roberto; Bonavina, Maria Giuseppina; Rossi, Carlo Riccardo; Rastrelli, Marco

2017-01-01

Desmoid tumor is a rare monoclonal fibroblast proliferation that is regarded as benign. The clinical management of desmoid tumors is very complex and requires a multidisciplinary approach because of the unpredictable disease course. For those cases localized in the anterior abdominal wall, symptomatic and unresponsive to medical treatment, radical resection and reconstruction with a prosthetic device are indicated. We present here a case of desmoid fibromatosis of the left anterolateral abdominal wall with a marked increase of the mass that required a large excision followed by reconstruction with biological matrix. The fact that it can be incorporated in patient tissue without a fibrotic response and that it can resist future infections, together with a very competetive price, made the new collagen matrix Egis® our first choice. PMID:28413398

Retroperitoneal Castleman's disease: US, CT and MRI findings

International Nuclear Information System (INIS)

Bonini, Claudio; Boretti, Juan J.; Villavicencio, Roberto; Oxilia, Hector; Costamagna, Cecilia; Ferrer, Jaime; Secchi, Mario

2003-01-01

Purpose: To describe de imaging features of this unusual localization of Castleman's disease. Materials and methods: Two patients (man: 62 years old, woman: 27 years old) with epigastric abdominal pain were studied. The physical examination was negative in the woman while in the other case a peri umbilical tumor was observed. The laboratory and the tumor markers were negative. Both patients had a history of appendectomy. US, TC and MRI were performed. After surgery the pathological examination included stain techniques with hematoxylin-eosin, Masson's techniques and PAS. Results: Retroperitoneal Castleman's disease in peri pancreatic localization (extremely rare). The US showed slight hypoechoic homogeneous lesions with clear rims. CT without contrast revealed isodense lesions and one of them presented a small calcification, the e.v. contrast CT showed a clear homogeneous reinforcement. MRI demonstrated hypointense lesions on T1, hyperintense on T2, and after the administration of gadolinium these lesions showed a marked reinforcement on the arterial phase, which persisted on the late venous phase. The differential diagnosis with pancreatic tumoral pathology was difficult. The pathological examination revealed a lymphoid angio follicular hyperplasia of hyaline vascular type. Conclusion: Retroperitoneal Castlelman's disease is a rare entity. The different imaging methods did not provide an accurate diagnosis of this entity since there are no pathognomonic features. The pathological examination was required to define the diagnosis in both reported cases. (author)

Diagnosis and management of nonsyndromic hereditary gingival fibromatosis in a 13 year old girl: Report of a rare case

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Lata Goyal

2012-01-01

Full Text Available Hereditary gingival fibromatosis is a rare condition characterized by various degree of gingival overgrowth. It usually develops as an isolated disorder but can manifest with multisystem syndrome. We are here presenting a case of a 13-year-old girl who presented with severe enlargement of gingiva covering all most the entire crown involving both maxillary and mandibular arches. Differential diagnosis includes drug-induced and idiopathic gingival enlargement. Excess gingival tissue was removed by full mouth gingivectomy and sent for histopathological examination. Postoperative course was uneventful and patient′s esthetics improved significantly. A 12 month postoperative period shows no recurrence.

Localized bilateral perirenal fibrosis, a rare cause of idiopathic retroperitoneal fibrosis

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Maja Kveder

2014-08-01

Full Text Available Background: Idiopathic retroperitoneal fibrosis is an infrequent process of unknown aetiology characterised by fibrous tissue proliferation in the retroperitoneum. Even less frequent is a localized form of this disease by a proliferation of fibrous tissue around single or both kidneys.Case report: We describe a case of 46-year old man in whom medical management was started for accidentally discovered arterial hypertension, which turned out to be difficult to control.   During diagnostic work-up of hypertension, an abdominal ultrasound was obtained a year later demonstrating slight bilateral caliectasis without obvious visible cause for it. Laboratory exams have shown significantly impaired renal function, normocytic anaemia, slightly higher sedimentation rate, increased CRP and normal urinalysis. Nephrologist has decided for hospitalisation during which magnetic resonance imaging was performed  showing a few mm wide tissue coats surrounding both kidneys with fluid lying between the coat and kidney capsule. A biopsy of perirenal mass has confirmed a dense cellular lesion consisted of interweaved fascicles of spindle-shaped cells. After exclusion of tumours and other causes, a diagnosis of retroperitoneal fibrosis was confirmed. Clinical picture and laboratory data corresponded to idiopathic form of this disease. A treatment with tamoxifen was started after patient refused treatment with methylprednisolone. During tamoxifen monotherapy, there was gradual significant improvement of general symptoms, notable decline in inflammation markers, improvement of anaemia, normalisation of kidney function, and normalisation of blood pressure. Conclusion: Retroperitoneal fibrosis is still an obscure and multifaceted disease. A proper selection of diagnostic methods is the key to correct and fast diagnosis as well as good grounding for proper treatment.

A case report and a literature review of primary retroperitoneal mucinous cystadenoma: the importance of imaging in diagnosis and management.

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Pesapane, Filippo; Renterghem, Sofie Van; Patella, Francesca; Visschere, Pieter De; Villeirs, Geert

2018-01-29

Primary retroperitoneal mucinous cystadenoma (PRMC) is an extremely rare tumor: its histogenesis and its biological behavior remain speculative. Since most retroperitoneal tumors are malignant, a preoperative diagnosis of benignity is essential and it can be reached through imaging examinations, allowing a conservative management approach. We describe the case of a 52-year-old woman with abdominal pain and a palpable mass. Computed tomography of the abdomen revealed a retroperitoneal cystic mass, which was resected successfully through laparoscopy and diagnosed as PRMC. Although there are no pathognomonic, clinical or radiological findings for PRMC, it should be included in the list of differential diagnoses and its imaging criteria of benignity should always be sought, with the aim to exclude malignant tumors.

Retroperitoneal Cellular Angiofibroma: A Rare Gynecological Entity

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Ana Brandão

2017-12-01

Full Text Available Cellular angiofibroma is a mesenchymal tumor, described in 1997, without gender preference, that usually appears at age 40. The vulvovaginal area is the most common site in women, mimicking vulvar benign tumors, like Bartholin gland cyst. However, there are a few described cases of a deep or extra-pelvic angiofibroma. Excision is the treatment of choice and the recurrence rate appears to be low. We present the case of a woman with a heterogeneous tumor in the right adnexial region. At the surgery, a retroperitoneal tumor was excised and the histopathological tissue analysis revealed a cellular angiofibroma.

Pancreatitis autoinmune asociada a fibrosis retroperitoneal: evolución tras dos años de seguimiento Autoimmune pancreatitis associated with retroperitoneal fibrosis: outcome after 24 months of follow-up

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M. Romero

2008-10-01

Full Text Available Introducción: la pancreatitis autoinmune es un tipo de pancreatitis crónica caracterizado por un infiltrado linfoplasmocitario y una elevación de IgG e IgG4, que se ha descrito asociada a diversas manifestaciones extrapancreáticas y enfermedades autoinmunes, lo cual apoya la teoría de un mecanismo autoinmune fisiopatólogico de base. Caso clínico: presentamos el caso de un varón que debutó simultáneamente con una pancreatitis autoinmune asociada a fibrosis retroperitoneal y lesión de la vía biliar extrapancreática, con respuesta total tras tratamiento con corticoides durante 4 meses y ausencia de recurrencia tras 24 meses de seguimiento. Discusión: la pancreatitis autoinmune es un tipo de pancreatitis crónica que probablemente forme parte de un proceso sistémico autoinmune, cuyas manifestaciones extrapancreáticas más frecuentes son la fibrosis retroperitoneal y las lesiones de la vía biliar extrapancreática. Su correcto diagnóstico e inicio precoz del tratamiento puede favorecer la resolución completa de las lesiones, principalmente en los casos de bajo grado de actividad, con menor probabilidad de recurrencia.Introduction: autoimmune pancreatitis is a kind of chronic pancreatitis characterized by the presence of lymphoplasmacytic infiltration and severely elevated serum IgG and IgG4, which has been associated to many extrapancreatic lesions and other autoimmune disorders, leading to the theory of an autoimmune mechanism involved in the pathogenesis of this disease. Case report: we report the case of a man who simultaneously presented with autoimmune pancreatitis associated with retroperitonal fibrosis, and a lesion of the extrapancreatic bile duct, with total response to corticosteroid treatment for 4 moths and absence of recurrence after 24 months of follow-up. Discussion: autoimmune pancreatitis is a kind of chronic pancreatitis that is probably a part of a systemic autoinmune disease, with retroperitoneal fibrosis and

Thoracic Stent Graft Implantation for Aortic Coarctation with Patent Ductus Arteriosus via Retroperitoneal Iliac Approach in the Presence of Small Sized Femoral Artery

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Ozge Korkmaz

2016-01-01

Full Text Available Endovascular stent graft implantation is a favorable method for complex aortic coarctation accompanied by patent ductus arteriosus. Herein, an 18-year-old woman with complex aortic coarctation and patent ductus arteriosus was successfully treated by endovascular thoracic stent graft via retroperitoneal approach. The reason for retroperitoneal iliac approach was small sized common femoral arteries which were not suitable for stent graft passage. This case is the first aortic coarctation plus patent ductus arteriosus case described in the literature which is treated by endovascular thoracic stent graft via retroperitoneal approach.

Computer assisted pyeloplasty in children the retroperitoneal approach

DEFF Research Database (Denmark)

Olsen, L H; Jorgensen, T M

2004-01-01

PURPOSE: We describe the first series of computer assisted retroperitoneoscopic pyeloplasty in children using the Da Vinci Surgical System (Intuitive Surgical, Inc., Mountainview, California) with regard to setup, method, operation time, complications and preliminary outcome. The small space...... with the Da Vinci Surgical System. With the patient in a lateral semiprone position the retroperitoneal space was developed by blunt and balloon dissection. Three ports were placed for the computer assisted system and 1 for assistance. Pyeloplasty was performed with the mounted system placed behind...

Retroperitoneal laparoscopic pyelolithotomy in renal pelvic stone versus open surgery - a comparative study.

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Singal, Rikki; Dhar, Siddharth

2018-01-01

The introduction of endourological procedures such as percutaneous nephrolithotomy and ureterorenoscopy have led to a revolution in the the management of urinary stone disease. The indications for open stone surgery have been narrowed significantly, making it a second- or third-line treatment option. To study the safety and efficacy of retroperitoneal laparoscopic pyelolithotomy in retroperitoneal renal stone. We compared the results of laparoscopic and open surgery in terms of easy accessibility, operative period, renal injuries, and early recovery. This prospective study was conducted on renal pelvic stone cases from January 2009 to February 2016 in Suchkhand Hospital, Agra, India. The study included a total of 1700 cases with the diagnosis of solitary renal pelvic stones. In group A - 850 cases - retroperitoneal laparoscopic pyelolithotomy was performed, while group B - 850 cases - underwent open pyelolithotomy. The mean operative time was less in group B than group A (74.83 min vs. 94.43 min) which was significant (p<0.001). The blood loss was less in the laparoscopic group than in the open group (63 mL vs. 103mL). There were statistically significant differences in the post-operative pain scores, and postoperative complications compared to group B (p<0.001). The mean hospital stay was less in group A (p<0.03), which was significant. Laparoscopic surgery reduces analgesic requirements, hospital stay, and blood loss. The disadvantages include the reduced working space, the cost of equipment and the availability of a trained surgeon.

Retroperitoneal cystic lymphangioma with change of internal morphology on follow-up ultrasound and CT: a case report

International Nuclear Information System (INIS)

Shin, G. H; Lim, J. W.; Lee, D. H.; Ko, Y. T.; Kim, B. H.; Yang, M. H.

1995-01-01

We report a case of retroperitoneal cystic lymphangioma in an 65-year-old male. Two years prior to this admission, a mass was incidentally detected by ultrasound during hospitalization for the treatment of lung cancer. Ultrasound study showed a multiloculated cystic mass with debris and CT revealed a fat-fluid level within the mass. On two years follow-up, the mass has changed into a unicameral mass without internal echogenicity on US and homogeneous water-density mass on CT. The mass was removed by surgery and confirmed as retroperitoneal cystic lymphangioma

Retroperitoneal cystic lymphangioma with change of internal morphology on follow-up ultrasound and CT: a case report

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Shin, G. H; Lim, J. W.; Lee, D. H.; Ko, Y. T.; Kim, B. H.; Yang, M. H. [College of Medicine, Kyung Hee University, Seoul (Korea, Republic of)

1995-08-15

We report a case of retroperitoneal cystic lymphangioma in an 65-year-old male. Two years prior to this admission, a mass was incidentally detected by ultrasound during hospitalization for the treatment of lung cancer. Ultrasound study showed a multiloculated cystic mass with debris and CT revealed a fat-fluid level within the mass. On two years follow-up, the mass has changed into a unicameral mass without internal echogenicity on US and homogeneous water-density mass on CT. The mass was removed by surgery and confirmed as retroperitoneal cystic lymphangioma.

Retroperitoneal abscess shortly after chemotherapy for lung cancer: A case report.

Science.gov (United States)

Ohara, Gen; Kondo, Tadashi; Kagohashi, Katsunori; Watanabe, Hiroko; Kawaguchi, Mio; Kurishima, Koichi; Satoh, Hiroaki; Hizawa, Nobuyuki

2014-03-01

To the best of our knowledge, the formation of a retroperitoneal abscess due to acute appendicitis shortly after administration of chemotherapy for lung cancer has not been previously reported. This is the case report of a 59-year-old male who was admitted to the Mito Medical Center (Mito, Japan) and diagnosed with lung adenocarcinoma with pleuritis carcinomatosis. Although no distant metastasis was identified, combination chemotherapy with cisplatin and pemetrexed was administered. Nine days after initiating chemotherapy, the patient developed right lower quadrant abdominal pain and high fever. Computed tomography (CT) of the abdomen and pelvis revealed the collection of gas and fluid in the retroperitoneum adjacent to the cecum. The abscess was locally drained; however, the infection continued to spread, with subsequent development of a scrotal abscess. Consequently, appendectomy was performed. The patient recovered well and the lung adenocarcinoma was treated with additional courses of chemotherapy following the remission of the local inflammation. Retroperitoneal abscess due to acute appendicitis is an unusual finding; however, this rare complication should be considered during or shortly after chemotherapy in patients with lung cancer.

Atypical presentations of retroperitoneal giant schwannomas

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Sait Ozbir

2011-06-01

Full Text Available Schwannomas are usually benign rare tumors that originating from Schwann cells of peripheral nerve sheaths. Presentation is generally varied and changed in a non-specific range from abdominal mass, flank pain to incidental findings. Herein we report 2 cases of retroperitoneal giant schwannomas with different clinical presentations, of whom one presented with vague abdominal pain, palpable abdominal mass for 4 years, swelling and bilateral hydronephrosis that caused by giant abdominal mass; the other one presented with right flank pain, rectal hemorrhage and lower extremities edema. Two patients were treated by complete surgical excision of masses. The histological and immunohistochemical diagnosis was reported as benign schwannoma. Both of patients are doing well and had no recurrence in 9 years and 28 months follow-up, respectively.

Pulmonary hyalinizing granuloma and retroperitoneal fibrosis in an adolescent

International Nuclear Information System (INIS)

Young, Adam S.; Binkovitz, Larry A.; Adler, Brent H.; Nicol, Kathleen K.; Rennebohm, Robert M.

2007-01-01

We describe a 15-year-old boy who developed pulmonary hyalinizing granuloma (PHG) and retroperitoneal fibrosis (RPF). His PHG and RPF were not associated with histoplasmosis or tuberculosis and appeared to represent idiopathic autoimmune phenomena. This is the first reported case of PHG in a pediatric patient and the fourth reported co-occurrence of PHG and RPF. The use of F-18 fluorodeoxyglucose positron emission tomography in the diagnostic and follow-up evaluation of PHG is reported. (orig.)

Pulmonary hyalinizing granuloma and retroperitoneal fibrosis in an adolescent

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Young, Adam S.; Binkovitz, Larry A.; Adler, Brent H. [Columbus Children' s Hospital, Children' s Radiological Institute, Columbus, OH (United States); Nicol, Kathleen K. [Columbus Children' s Hospital, Department of Pathology, Columbus, OH (United States); Rennebohm, Robert M. [Columbus Children' s Hospital, Department of Rheumatology, Columbus, OH (United States)

2007-01-15

We describe a 15-year-old boy who developed pulmonary hyalinizing granuloma (PHG) and retroperitoneal fibrosis (RPF). His PHG and RPF were not associated with histoplasmosis or tuberculosis and appeared to represent idiopathic autoimmune phenomena. This is the first reported case of PHG in a pediatric patient and the fourth reported co-occurrence of PHG and RPF. The use of F-18 fluorodeoxyglucose positron emission tomography in the diagnostic and follow-up evaluation of PHG is reported. (orig.)

Pharmacokinetics of cephem antibiotics in exudate of pelvic retroperitoneal space after radical hysterectomy and pelvic lymphadenectomy.

Science.gov (United States)

Ito, K; Hayasaki, M; Tamaya, T

1990-01-01

Many cephalosporin antibiotics have recently been invented and attempts have been made to use them clinically. The choice of which of these drugs should be used has been difficult in gynecology. The efficacies of these drugs depend on their antibacterial spectra, potencies, and concentrations in tissues. This study was designed to investigate the pharmacokinetics of various cephem antibiotics in the exudate of the retroperitoneal space that is formed after radical hysterectomy and pelvic lymphadenectomy. These cephem antibiotics were cefoxitin, cefotiam, cefotetan, cefpiramide, cefminox, cefotaxime, ceftizoxime, cefoperazone, cefmenoxime, cefbuperazone, ceftazidime, cefpimizole, flomoxef, and cefuzonam. The maximum concentrations after administration of a 1-g dose in the exudate of the pelvic retroperitoneal space were 37.9 micrograms/ml with cefminox, 30.3 micrograms/ml with cefpimizole, 21.6 micrograms/ml with flomoxef, 21.5 micrograms/ml with ceftazidime, and 17.6 micrograms/ml with cefbuperazone, which were relatively high. When selecting antibiotics for prophylactic use against infections in the retroperitoneal space after radical hysterectomy and pelvic lymphadenectomy, on the basis of drug transfer, flomoxef, cefminox, cefbuperazone, ceftazidime, and cefpimizole were considered to be the drugs of first choice at a dose of 1 g. PMID:2393276

Retroperitoneal endodermal sinus tumor patient with palliative care needs

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Surbhi Kashyap

2016-01-01

Full Text Available This article is a case reflection of a personal encounter on the palliative care treatment required after the removal of a complicated case of a primary extra-gonadal retro-peritoneal endodermal sinus tumor (yolk sac tumor. This reflection is from the perspective of a recently graduated MD student who spent one month with an Indian pain management and palliative care team at the Institute Rotary Cancer Hospital (IRCH, All India Institute of Medical Sciences (AIIMS, New Delhi

A cutting biopsy needle for the histological diagnosis of abdominal and retroperitoneal masses

International Nuclear Information System (INIS)

Hauenstein, K.H.; Wimmer, B.; Freudenberg, N.; Freiburg Univ.

1985-01-01

A new cutting biopsy needle has been used to obtain histologically useful material while causing the minimum of trauma. It permits biopsies of organs, but its small external diameter of 0.8 or 0.95 mm makes it possible to carry out transperitoneal puncture of the stomach, colon or liver and of the retroperitoneal space, using a ventral approach. Tissue samples were obtained in 96% of 63 patients. The risk of complications is no higher than for conventional needles used for cytology. The accuracy with which the material can be obtained is therefore the most important problem. The position of the area to be biopsied should determine whether the biopsy is to be aided by sonography or CT. Biopsies of organs can be appropriately carried out under ultrasound control, but processes in the pelvis and in retroperitoneal-paravertebral and extra-peritoneal positions are best biopsied under CT control. (orig.) [de

Intestinal duplication and retroperitoneal teratoma in child hoof: a case report

International Nuclear Information System (INIS)

Atzingen, Augusto Castelli Von; Bazzano, Felix Carlos Ocariz; Tiburzio, Nicolas Biagione; Grande, Rogerio Mendes; Juntolli Netto, Joao Diniz

2007-01-01

The authors present a case of intestinal duplication and retroperitoneal teratoma in a 7-year-old patient with evident mass and abdominal pain to explain; that it was submitted to study conventional X-ray, ultrasonography, computed tomography and subsequent exploiting laparotomia. The anatomopathological study verified intestinal duplication and ripe teratoma. In the existent medical literature it was not found any similar case. (author)

Surgical experience of laparoscopic retroperitoneal triple neurectomy for a patient with chronic neuropathic inguinodynia

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Masato Narita

2017-01-01

Conclusions: Laparoscopic retroperitoneal triple neurectomy is useful for treating refractory neuropathic pain. The diagnosis of neuropathic pain via thorough preoperative assessment is vital for procedure success because the procedure would not be effective for other types of pain.

Histology-based classification predicts pattern of recurrence and improves risk stratification in primary retroperitoneal sarcoma

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Tan, Marcus C.B.; Brennan, Murray F.; Kuk, Deborah; Agaram, Narasimhan P.; Antonescu, Cristina; Qin, Li-Xuan; Moraco, Nicole; Crago, Aimee M.; Singer, Samuel

2015-01-01

Objective To determine the prognostic significance of histologic type/subtype in a large series of patients with primary resected retroperitoneal sarcoma. Summary Background Data The histologic diversity and rarity of retroperitoneal sarcoma has hampered the ability to predict patient outcome. Methods From a single-institution, prospective database, 675 patients treated surgically for primary, non-metastatic retroperitoneal sarcoma during 1982–2010 were identified and histologic type/subtype was reviewed. Clinicopathologic variables were analyzed for association with disease-specific death (DSD), local recurrence (LR), and distant recurrence (DR). Results Median follow-up for survivors was 7.5 years. The predominant histologies were well-differentiated liposarcoma, dedifferentiated liposarcoma, and leiomyosarcoma. Five-year cumulative incidence of DSD was 31%, and factors independently associated with DSD were R2 resection, resection of ≥3 contiguous organs, and histologic type. Five-year cumulative incidence for LR was 39% and for DR was 24%. R1 resection, age, tumor size, and histologic type were independently associated with LR; size, resection of ≥3 organs, and histologic type were independently associated with DR. Liposarcoma and leiomyosarcoma were associated with late recurrence and DSD (as long as 15 years from diagnosis). For solitary fibrous tumor, local recurrence was uncommon (sarcoma. Histology predicts the pattern and incidence of LR and DR and will aid in more accurate patient counseling and selection of patients for adjuvant therapy trials. PMID:25915910

An Extremely Rare and Unusual Case of Retroperitoneal and Pelvic Metastasis from Squamous Cell Carcinoma of Vallecula

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Abhishek Purkayastha

2016-06-01

Full Text Available We report an extremely rare and unusual case of retroperitoneal and pelvic metastasis from primary squamous cell carcinoma of vallecula. Generally carcinoma oropharynx metastasizes to lungs, liver and bone while retroperitoneal and pelvic metastasis is rarely heard of. To the best of our knowledge this case is one of the scantly reported cases ever of this kind in the world.  A 60-year-old male presented with dysphagia and hoarseness of voice of four month duration.  Computed tomography (CT scan face and neck showed growth right vallecula. Biopsy of lesion showed squamous cell carcinoma. Metastatic work up was negative. He received definitive chemo-radiation. Patient during follow up presented with dyspepsia, abdominal discomfort and weight loss. Whole body positron emission tomography (WB PET scan revealed retroperitoneal and pelvic lymph node deposits which were confirmed as metastasis of squamous cell carcinoma by CT guided fine needle aspiration cytology (FNAC. Patient was exhibited palliative chemotherapy but his general condition deteriorated and he finally succumbed to his metastatic illness. This case is being reported to highlight its extreme rarity, the diagnostic and therapeutic challenges it presented and its overall dismal prognosis.

Clinical observation on the therapeutic efficacy of CyberKnife for primary or metastatic retroperitoneal tumors

International Nuclear Information System (INIS)

Zhuang Hongqing; Yuan Zhiyong; Wang Ping

2012-01-01

Objective: To evaluate the early response rate and radiation toxicity of CyberKnife in the treatment of primary or metastatic retroperitoneal tumors. Methods: Twenty-eight patients with retroperitoneal tumors were treated with CyberKnife. The total doses were 2000-6000 cGy (median 4500 cGy) and biological effective doses were 3750-10080 cGy (median 7680 cGy) in 2-10 fractions (median 5). Of all patients, 3 received three dimensional conformal radiotherapy (3DCRT) or intensity modulated radiotherapy (IMRT) boost, 1 was treated as second-course radiotherapy, and others were treated with CyberKnife only. The survival rates were calculated by Kaplan-Meier method and compared with Logrank test. Results: The complete response, stable disease and progression disease rates were 43% (12/28), 6% (10/28), 18% (5/28), 4%, (1/28), respectively. The overall response rate was 96%. The number of patients who were followed up more than 1, 2, 3 years were 17, 9, 7, respectively. The 1-, 2- and 3-year local control rates were 92%, 86%, and 86%, respectively. The 1-, 2- and 3-year overall survival rates were 60%, 49% and 49%, respectively. The difference between local progression-free survival and overall survival was not significant (median 9.5 and 12.0 months, χ 2 =0.17, P=0.680), Moreover, if the patients did not have metastasis elsewhere and local treatment was effective, there was no significant difference between local progression-free survival and progression free survival (median 17 and 11 months, χ 2 =0.13, P=0.720), Acute radiation-induced side effects (≥ 2 grade) such as fatigue, anorexia, nausea, vomiting and epigastric discomfort occurred in 9, 9, 7, 7 and 2 patients, respectively. Intestinal stenosis of 1 grade occurred in 1 patients. Conclusions: Radiotherapy for retroperitoneal tumors with CyberKnife has provided a high response rate with minimal side effects. It is a safe and effective local treatment method for retroperitoneal tumors. (authors)

Unstable patients with retroperitoneal vascular trauma: an endovascular approach.

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Boufi, Mourad; Bordon, Sébastien; Dona, Bianca; Hartung, Olivier; Sarran, Anthony; Nadeau, Sébastien; Maurin, Charlotte; Alimi, Yves S

2011-04-01

In hemodynamically unstable patients, the management of retroperitoneal vascular trauma is both difficult and challenging. Endovascular techniques have become an alternative to surgery in several trauma centers. Between 2004 and 2006, 16 patients (nine men, mean age: 46 years, range: 19-79 years) with retroperitoneal vascular trauma and hemodynamic instability were treated using an endovascular approach. The mean injury severity score was 30.7 ± 13.1. Mean systolic blood pressure and the shock index were 74 mm Hg and 1.9, respectively. Vasopressor drugs were required in 68.7% of cases (n = 11). Injuries were attributable to road traffic accidents (n = 15) and falls (n = 1). The hemorrhage sites included the internal iliac artery or its branches (n = 12) with bilateral injury in one case, renal artery (n = 2), abdominal aorta (n = 1), and lumbar artery (n = 1). In all, 14 coil embolizations and three stent-grafts were implanted. The technical success rate was 75%, as early re-embolization was necessary in one case and three patients died during the perioperative period. Six patients died during the period of hospitalization (37.5%). No surgical conversion or major morbidity was reported. In comparison with particulates, coil ± stent-graft may provide similar efficacy with regard to survival, and thus may be a valuable solution when particulate embolization is not available or feasible. Copyright © 2011 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.

Dyspareunia in a Teenager Reveals a Rare Occurrence: Retroperitoneal Cervical Leiomyoma of the Left Pararectal Space.

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Giannella, Luca; Mfuta, Kabala; Tuzio, Antonella; Cerami, Lillo Bruno

2016-02-01

Retroperitoneal uterine leiomyoma is a very rare occurrence and to discover it as a cause of female sexual dysfunction in a teen is unusual. An 18-year-old black woman reported deep dyspareunia, resulting in severe distress. Gynecological and instrumental examinations showed a pelvic mass of 7 cm in diameter. The preoperative diagnosis was uterine fibroid, but the exact location of the leiomyoma was uncertain. Laparoscopic examination showed a pedunculated retroperitoneal cervical leiomyoma in the left pararectal space. After surgical excision of the mass, normal sexual activity was restored. When a teen experiences pain with intercourse, pelvic masses should be part of differential diagnosis of dyspareunia. Copyright © 2016 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Spontaneous Retroperitoneal Hematoma Simulating Ruptured Infrarenal Aortic Aneurysm in a Patient with End-Stage Renal Disease

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Li, JYY; Chan, YC; Qing, KX; Cheng, SW

2014-01-01

We reported a case of spontaneous retroperitoneal hematoma (SRH) simulating a ruptured infrarenal aortic aneurysm. A 72-year-old man with a history of infrarenal aortic aneurysm and end-stage renal disease on hemodialysis presented with malaise and nonspecific central abdominal pain and left loin discomfort. An emergency computed tomography scan showed a large retroperitoneal hematoma and clinical suspicion of ruptured infrarenal aortic aneurysm. However, the hematoma was discontinuous with the aneurysm sac and raised the clinical suspicion on dual pathology. The SRH was treated conservatively with transfusion of blood products, and the aneurysm was treated with nonemergency endovascular repair electively. This case demonstrates the importance of recognizing different clinical and radiological characteristics and be aware of dual pathology. PMID:28031651

Design and Calibration of an RF Actuator for Low-Level RF Systems

Science.gov (United States)

Geng, Zheqiao; Hong, Bo

2016-02-01

X-ray free electron laser (FEL) machines like the Linac Coherent Light Source (LCLS) at SLAC require high-quality electron beams to generate X-ray lasers for various experiments. Digital low-level RF (LLRF) systems are widely used to control the high-power RF klystrons to provide a highly stable RF field in accelerator structures for beam acceleration. Feedback and feedforward controllers are implemented in LLRF systems to stabilize or adjust the phase and amplitude of the RF field. To achieve the RF stability and the accuracy of the phase and amplitude adjustment, low-noise and highly linear RF actuators are required. Aiming for the upgrade of the S-band Linac at SLAC, an RF actuator is designed with an I/Qmodulator driven by two digital-to-analog converters (DAC) for the digital LLRF systems. A direct upconversion scheme is selected for RF actuation, and an on-line calibration algorithm is developed to compensate the RF reference leakage and the imbalance errors in the I/Q modulator, which may cause significant phase and amplitude actuation errors. This paper presents the requirements on the RF actuator, the design of the hardware, the calibration algorithm, and the implementation in firmware and software and the test results at LCLS.

Retroperitoneal fibrosis: a report of 4 cases

International Nuclear Information System (INIS)

Salvatore, Maria G.; Palermo, Mariano; Zamboni, Marcelo; Mena, Luis E.; Tarsitano, Francisco

2004-01-01

Four cases of RF diagnosed in the last three years, are reported. Gold standard methods of diagnosis at present are CT and MRI. CT scan shows isodense mass involving the aorta and inferior cava vein as well as ureteral compression. MRI shows a fibrotic plaque hypointense in T1, surrounding the large vessels. Treatment of RF, primary or idiopathic, aims at resolving ureteral obstruction, restoring renal function and preventing infections. (author)

A Rare Case of Retroperitoneal Follicular Dendritic Cell Sarcoma Identified by 99mTc-HYNIC-TOC SPECT/CT.

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Li, Yi; Xu, Xiaoping; Xu, Junyan; Huang, Dan

2018-05-31

Follicular dendritic cell sarcoma is a very rare neoplasm, which is not lymphoma, but originates from a type of immune cells called follicular dendritic cells. We presented a 37-year-old woman who has suffered from obstructive jaundice, weight loss and right upper abdominal pain for 2 months. The contrast CT revealed masses located in the region of pancreatic head and lots of enlarged retroperitoneal lymph nodes, both of which were enhanced on the artery phase of CT images. Meanwhile, Tc-HYNIC-TOC SPECT/CT revealed high activity in the corresponding lesions. After biopsy, the masses were pathologically confirmed as retroperitoneal follicular dendritic cell sarcoma.

Retroperitoneal abscess shortly after chemotherapy for lung cancer: A case report

OpenAIRE

OHARA, GEN; KONDO, TADASHI; KAGOHASHI, KATSUNORI; WATANABE, HIROKO; KAWAGUCHI, MIO; KURISHIMA, KOICHI; SATOH, HIROAKI; HIZAWA, NOBUYUKI

2013-01-01

To the best of our knowledge, the formation of a retroperitoneal abscess due to acute appendicitis shortly after administration of chemotherapy for lung cancer has not been previously reported. This is the case report of a 59-year-old male who was admitted to the Mito Medical Center (Mito, Japan) and diagnosed with lung adenocarcinoma with pleuritis carcinomatosis. Although no distant metastasis was identified, combination chemotherapy with cisplatin and pemetrexed was administered. Nine days...

Retroperitoneal myxoid liposarcoma of the renal capsule causing Budd-Chiari syndrome

International Nuclear Information System (INIS)

Gruetzner, G.; Fuerst, G.; Kuhn, F.P.; Kliche, K.O.

1991-01-01

A retroperitoneal myxoid liposarcoma of the renal capsule must be differentiated from renal cell carcinomas, angiomyolipomas, fibrogenous lipomas, fibrolipomas and mixed tumours containing fat tissue. Myxoid liposarcomas can lead to intracavale tumourthromboses, which is often the case with renal cell carcinomas and revealed clinical with Budd-Chiari syndrome. Computed tomography and magnetic resonance imaging give additional information in the diagnosis of intracaval tumourthromboses and show the exact expansion of the topographic-anatomical structure. (orig.) [de

RF transport

International Nuclear Information System (INIS)

Choroba, Stefan

2013-01-01

This paper deals with the techniques of transport of high-power radiofrequency (RF) power from a RF power source to the cavities of an accelerator. Since the theory of electromagnetic waves in waveguides and of waveguide components is very well explained in a number of excellent text books it will limit itself on special waveguide distributions and on a number of, although not complete list of, special problems which sometimes occur in RF power transportation systems. (author)

Retroperitoneal aortic hemorrhage caused by penetration of an endovascular stent-graft anchoring barb.

Science.gov (United States)

Twine, Christopher P; Winterbottom, Andrew; Shaida, Nadeem; Boyle, Jonathan R

2013-08-01

To report a rare case of acute intraoperative retroperitoneal hemorrhage secondary to aortic penetration by the suprarenal anchoring barb on a stent-graft. A 75-year-old patient on dual antiplatelet therapy for coronary stents and low-molecular-weight heparin for atrial thrombus underwent elective endovascular repair of a 6.7-cm infrarenal abdominal aortic aneurysm. A device with suprarenal fixation and metal anchoring barbs was implanted, and a molding balloon was used that at no time covered the proximal bare metal stents or barbs. In recovery, the patient became tachycardic and hypotensive. After resuscitation, imaging identified an anterior barb penetrating the aortic wall, causing the acute retroperitoneal hemorrhage. A decision to treat conservatively rather than resort to open surgery was difficult but ultimately influenced by the patients' high risk for open surgery. The patient was treated by aggressive reversal of heparin and platelet transfusion, and the bleed settled spontaneously. Major surgery and subsequent morbidity may be avoided by medical management of what would appear to be a surgical problem.

Hidatidosis retroperitoneal secundaria a quiste hidatídico de localización hepática Retroperitoneal hydatidosis secondary to hepatic hydatid cyst

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Katherina A Vizcaychipi

2012-12-01

Full Text Available La hidatidosis es una enfermedad de distribución mundial, producida por un platelminto parásito del género Echinococcus. El caso que se presenta corresponde a una paciente con una tumoración fluctuante en el espacio retroperitoneal lumbar, secundaria a un quiste hepático. El diagnóstico inicial de certeza fue dado por el hallazgo de ganchos rostelares de protoescólices en el líquido aspirado de un absceso. Este trabajo describe el cuadro clínico, el diagnóstico y el tratamiento médico-quirúrgico de esta paciente. Se analiza cómo la elaboración de un diagnóstico certero requiere de un análisis adecuado de los antecedentes epidemiológicos, las manifestaciones clínicas, los estudios de imágenes y las pruebas de laboratorio, ya que el conjunto de estos datos confirman el caso.Hydatid disease in a worldwide zoonosis. It is caused by a parasitic platyhelminth of the genus Echinococcus. We present a patient with a fluctuating lumbar tumor in the retroperitoneal space, secondary to a hepatic cyst. The initial diagnosis was made by identification of rostellar hooks from protoscoleces in the fluid aspirated from the abscess. We herein describe the clinical manifestations, diagnosis and medical and surgical treatment of this unusual case and conclude that the development of an accurate diagnosis required a proper analysis of the patient's epidemiological history, clinical manifestations, imaging studies and laboratory tests. A multidisciplinary approach and differential diagnosis is paramount to be able to establish a cause of the disease to deliver appropriate treatment.

Femtosecond precision measurement of laser–rf phase jitter in a photocathode rf gun

International Nuclear Information System (INIS)

Shi, Libing; Zhao, Lingrong; Lu, Chao; Jiang, Tao; Liu, Shengguang; Wang, Rui; Zhu, Pengfei; Xiang, Dao

2017-01-01

We report on the measurement of the laser–rf phase jitter in a photocathode rf gun with femtosecond precision. In this experiment four laser pulses with equal separation are used to produce electron bunch trains; then the laser–rf phase jitter is obtained by measuring the variations of the electron bunch spacing with an rf deflector. Furthermore, we show that when the gun and the deflector are powered by the same rf source, it is possible to obtain the laser–rf phase jitter in the gun through measurement of the beam–rf phase jitter in the deflector. Based on these measurements, we propose an effective time-stamping method that may be applied in MeV ultrafast electron diffraction facilities to enhance the temporal resolution.

Femtosecond precision measurement of laser–rf phase jitter in a photocathode rf gun

Energy Technology Data Exchange (ETDEWEB)

Shi, Libing; Zhao, Lingrong; Lu, Chao; Jiang, Tao; Liu, Shengguang; Wang, Rui; Zhu, Pengfei; Xiang, Dao, E-mail: dxiang@sjtu.edu.cn

2017-03-21

We report on the measurement of the laser–rf phase jitter in a photocathode rf gun with femtosecond precision. In this experiment four laser pulses with equal separation are used to produce electron bunch trains; then the laser–rf phase jitter is obtained by measuring the variations of the electron bunch spacing with an rf deflector. Furthermore, we show that when the gun and the deflector are powered by the same rf source, it is possible to obtain the laser–rf phase jitter in the gun through measurement of the beam–rf phase jitter in the deflector. Based on these measurements, we propose an effective time-stamping method that may be applied in MeV ultrafast electron diffraction facilities to enhance the temporal resolution.

Rf power sources

International Nuclear Information System (INIS)

Allen, M.A.

1988-01-01

In this paper, the author reports on RF power sources for accelerator applications. The approach will be with particular customers in mind. These customers are high energy physicists who use accelerators as experimental tools in the study of the nucleus of the atom, and synchrotron light sources derived from electron or positron storage rings. The author pays close attention to electron- positron linear accelerators since the RF sources have always defined what is possible to achieve with these accelerators. Circular machines, cyclotrons, synchrotrons, etc. have usually not been limited by the RF power available and the machine builders have usually had their RF power source requirements met off the shelf. The main challenge for the RF scientist has been then in the areas of controls. An interesting example of this is in the Conceptual Design Report of the Superconducting Super Collider (SSC) where the RF system is described in six pages of text in a 700-page report. Also, the cost of that RF system is about one-third of a percent of the project's total cost. The RF system is well within the state of the art and no new power sources need to be developed. All the intellectual effort of the system designer would be devoted to the feedback systems necessary to stabilize beams during storage and acceleration, with the main engineering challenges (and costs) being in the superconducting magnet lattice

Diode laser versus scalpel in the treatment of hereditary gingival fibromatosis in a 6-year old boy

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Samia Aboujaoude

2016-11-01

Full Text Available Hereditary gingival fibromatosis (HGF is a rare disease characterized by a benign enlargement of the gingiva involving both the mandible and the maxilla. This case is about a 6-year-old child with non syndromic HGF showing a severe gingival enlargement covering almost all surfaces of the teeth, in both arches, hence causing major aesthetic, phonetic and masticatory problems. The aim of the present article is to compare the outcomes of two therapeutical approaches: i classical surgical removal with scalpel; and ii diode laser resection. Compared to the surgical approach, the clinical results show that the main advantages of the diode laser technique are a better visibility during the intervention, minimal postoperative discomfort combined to a better gingival recontouring. However, the time consumption and the high cost of the laser equipment remain the main disadvantages of the systematic use of this technique.

RF Measurement Concepts

CERN Document Server

Caspers, F

2014-01-01

For the characterization of components, systems and signals in the radiofrequency (RF) and microwave ranges, several dedicated instruments are in use. In this article the fundamentals of the RF signal techniques are discussed. The key element in these front ends is the Schottky diode which can be used either as a RF mixer or as a single sampler. The spectrum analyser has become an absolutely indispensable tool for RF signal analysis. Here the front end is the RF mixer as the RF section of modern spectrum analyses has a ra ther complex architecture. The reasons for this complexity and certain working principles as well as limitations are discussed. In addition, an overview of the development of scalar and vector signal analysers is given. For the determination of the noise temperature of a one-port and the noise figure of a two-port, basic concepts and relations are shown as well as a brief discussion of commonly used noise-measurement techniques. In a further part of this article the operating principles of n...

Microscopic investigation of RF surfaces of 3 GHz niobium accelerator cavities following RF processing

International Nuclear Information System (INIS)

Graber, J.; Barnes, P.; Flynn, T.; Kirchgessner, J.; Knobloch, J.; Moffat, D.; Muller, H.; Padamsee, H.; Sears, J.

1993-01-01

RF processing of Superconducting accelerating cavities is achieved through a change in the electron field emission (FE) characteristics of the RF surface. The authors have examined the RF surfaces of several single-cell 3 GHz cavities, following RF processing, in a Scanning Electron Microscope (SEM). The RF processing sessions included both High Peak Power (P ≤ 50 kW) pulsed processing, and low power (≤ 20 W) continuous wave processing. The experimental apparatus also included a thermometer array on the cavity outer wall, allowing temperature maps to characterize the emission before and after RF processing gains. Multiple sites have been located in cavities which showed improvements in cavity behavior due to RF processing. Several SEM-located sites can be correlated with changes in thermometer signals, indicating a direct relationship between the surface site and emission reduction due to RF processing. Information gained from the SEM investigations and thermometry are used to enhance the theoretical model of RF processing

Rare aggressive behavior of MDM2-amplified retroperitoneal dedifferentiated liposarcoma, with brain, lung and subcutaneous metastases

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Imen Ben Salha

2016-10-01

Full Text Available Dedifferentiated liposarcoma (DDL is a histologically pleomorphic sarcoma, traditionally defined as well-differentiated liposarcoma with abrupt transition to high grade, nonlipogenic sarcoma. It can occur as part of recurrent well-differentiated liposarcoma, or may arise de novo. DDL most frequently occurs within the retroperitoneum, and while it is prone to local recurrence, it usually has a lower rate of metastasis than other pleomorphic sarcomas. We describe a case of retroperitoneal dedifferentiated liposarcoma in a 63-year-old male, who showed MDM2 amplification with fluorescence in situ hybridization, which displayed unusually aggressive behavior, with brain, lung and subcutaneous soft tissue metastases. As previous reports of metastatic liposarcoma have largely grouped DDL in with other (genetically and clinically distinct liposarcoma subtypes, we highlight and discuss the rare occurrence of brain metastasis in MDM2-amplified retroperitoneal liposarcoma.

Retroperitoneal approach for robot-assisted partial nephrectomy: technique and early outcomes

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A. Porreca

Full Text Available ABSTRACT Objectives The aim of our study is to present early outcomes of our series of retroperitoneal-RAPN (Robot Assisted Partial Nephrectomy. Materials and methods From September 2010 until December 2015, we performed 81 RAPN procedures (44 at left kidney and 37 at right. Average size was 3cm (1-9. Average PADUA score 7.1 (5-10. Average surgical time (overall and only robot time, ischemia time, blood loss, pathological stage, complications and hospital stay have been recorded. Results All of the cases were completed successfully without any operative complication or surgical conversion. Average surgical time was 177 minutes (75-340. Operative time was 145 minutes (80-300, overall blood loss was 142cc (60-310cc. In 30 cases the pedicle was late clamped with an average ischemia time of 4 minutes (2-7. None of the patient had positive surgical margins at definitive histology (49pT1a, 12pT1b, 3pT2a, 2pT3a. Hospital stay was 3 days (2-7. Conclusions The retroperitoneal robotic partial nephrectomy approach is safe and allows treatment of even quite complex tumors. It also combines the already well known advantages guaranteed by the da Vinci® robotic surgical system, with the advantages of the retroperitoneoscopic approach.

Primary or recurring extra-abdominal desmoid fibromatosis: assessment of treatment by observation only.

Science.gov (United States)

Barbier, O; Anract, P; Pluot, E; Larouserie, F; Sailhan, F; Babinet, A; Tomeno, B

2010-12-01

Extra-abdominal desmoid fibromatosis (EADF) is a benign tumoral condition, classically managed by more or less radical and sometimes mutilating excision. This treatment strategy is associated with a recurrence rate of nearly 50% according to various reports. EADF may show spontaneous stabilization over time. A retrospective series of 26 cases of EADF managed by simple observation was studied to assess spontaneous favorable evolution and identify possible factors impacting evolution. Eleven cases were of primary EADF with no treatment or surgery, and 15 of recurrence after surgery with no adjuvant treatment. MRI was the reference examination during follow-up. Twenty-four cases showed stabilization at a median 14 months; there were no cases of renewed evolution after stabilization. One primary tumor showed spontaneous regression, and one recurrence still showed evolution at end of follow-up (23 months). The sole factor impacting potential for evolution was prior surgery. No radiologic or pathologic criteria of evolution emerged from analysis. The present series, one of the largest dedicated to EADF managed by observation, confirmed recent literature findings: a conservative "wait-and-see" attitude is reasonable and should be considered when large-scale resection would entail significant functional or esthetic impairment. Level IV, retrospective study. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Percutaneous embolisation of retroperitoneal bleeding from pelvic fractures

International Nuclear Information System (INIS)

Grabenwoeger, F.; Dock, W.; Ittner, G.; Vienna Univ.

1989-01-01

Pelvic fractures may lead to severe retroperitoneal bleeding. Percutaneous catheter embolisation has become an increasingly important therapeutic alternative to surgical intervention. Most studies dealing with this problem have been small and we have attempted to evaluate the method on the basis of our own experience and a review of the literature. The success rate of percutaneous embolisation appears to be about 94%. The use of blood transfusion dropped from an average of 25.7 units before embolisation to an average of 6.5 units after embolisation. In spite of this, mortality in these patients remains high at 43.3% because of the serious additional injuries. The advantages and disadvantages of various embolising materials are discussed and various techniques of percutaneous embolisation are described. (orig.) [de

Transformação carcinomatosa de endometriose retroperitoneal

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João Augusto dos Santos Martines

2012-08-01

Full Text Available Os autores apresentam o caso de uma paciente de 45 anos de idade, portadora de dor abdominal crônica, sendo evidenciada massa retroperitoneal cuja biopsia por agulha revelou tratar-se de endometriose. Submetida a ooforectomia bilateral. A paciente evoluiu, durante 4 anos, sem controle do quadro álgico, com perda de peso e aumento das dimensões da massa tumoral. A exérese cirúrgica total da massa tumoral não foi possível devido às aderências às estruturas vasculares. O pós-operatóriofoi complicado com quadro séptico evoluindo a óbito. O resultado anatomopatológico fornecido pela autópsia foi de adenocarcinoma de padrão endometrióide.

IgG4-related retroperitoneal fibrosis and sclerosing cholangitis independent of autoimmune pancreatitis. A recurrent case after a 5-year history of spontaneous remission.

Science.gov (United States)

Miura, Hideaki; Miyachi, Yasutaka

2009-07-06

A new clinicopathological concept of IgG4-related sclerosing disease affecting various organs has recently been proposed in relation to autoimmune pancreatitis. This report describes the case of IgG4-related retroperitoneal fibrosis and sclerosing cholangitis independent of autoimmune pancreatitis, which recurred after a long period of spontaneous remission. An 80-year-old Japanese man presented with obstructive jaundice owing to a hepatic hilum bile duct stricture. Coincidentally, a soft tissue mass surrounding the abdominal aorta, suggesting retroperitoneal fibrosis, was identified. Unexpectedly, spontaneous regression of obstructive jaundice together with retroperitoneal fibrosis occurred. The presence of high serum IgG4 concentrations measured later led us to consider a possible association with autoimmune pancreatitis; however, there were no clinical features confirming autoimmune pancreatitis. After a 5-year history of spontaneous clinical remission, there was an elevation of serum IgG4 levels and renal dysfunction owing to bilateral hydronephrosis caused by a reemergence of the retroperitoneal mass. Evaluation by endoscopic retrograde cholangiopancreatography revealed a biliary stricture, suggesting sclerosing cholangitis which was observed without the presence of any pancreatic duct abnormality. The subsequent excellent results obtained using steroid therapy, namely the decrease in serum IgG4 levels and the regression of the retroperitoneal mass, strongly suggested that the present case was an IgG4-related sclerosing disease. Aside from high serum IgG4 concentrations, markedly elevated levels of serum IgE was found retrospectively, although the clinical significance remains unknown. When we encounter fibrotic diseases of unknown etiology, we should measure serum IgG4 concentrations and monitor the disease activity over long periods even after achieving clinical remission.

RF study and 3-D simulations of a side-coupling thermionic RF-gun

International Nuclear Information System (INIS)

Rimjaem, S.; Kusoljariyakul, K.; Thongbai, C.

2014-01-01

A thermionic RF-gun for generating ultra-short electron bunches was optimized, developed and used as a source at a linac-based THz radiation research laboratory of the Plasma and Beam Physics Research Facility, Chiang Mai University, Thailand. The RF-gun is a π/2-mode standing wave structure, which consists of two S-band accelerating cells and a side-coupling cavity. The 2856 MHz RF wave is supplied from an S-band klystron to the gun through the waveguide input-port at the cylindrical wall of the second cell. A fraction of the RF power is coupled from the second cell to the first one via a side-coupling cavity. Both the waveguide input-port and the side-coupling cavity lead to an asymmetric geometry of the gun. RF properties and electromagnetic field distributions inside the RF-gun were studied and numerically simulated by using computer codes SUPERFISH 7.19 and CST Microwave Studio 2012 © . RF characterizations and tunings of the RF-gun were performed to ensure the reliability of the gun operation. The results from 3D simulations and measurements are compared and discussed in this paper. The influence of asymmetric field distributions inside the RF-gun on the electron beam properties was investigated via 3D beam dynamics simulations. A change in the coupling-plane of the side-coupling cavity is suggested to improve the gun performance

RF study and 3-D simulations of a side-coupling thermionic RF-gun

Science.gov (United States)

Rimjaem, S.; Kusoljariyakul, K.; Thongbai, C.

2014-02-01

A thermionic RF-gun for generating ultra-short electron bunches was optimized, developed and used as a source at a linac-based THz radiation research laboratory of the Plasma and Beam Physics Research Facility, Chiang Mai University, Thailand. The RF-gun is a π/2-mode standing wave structure, which consists of two S-band accelerating cells and a side-coupling cavity. The 2856 MHz RF wave is supplied from an S-band klystron to the gun through the waveguide input-port at the cylindrical wall of the second cell. A fraction of the RF power is coupled from the second cell to the first one via a side-coupling cavity. Both the waveguide input-port and the side-coupling cavity lead to an asymmetric geometry of the gun. RF properties and electromagnetic field distributions inside the RF-gun were studied and numerically simulated by using computer codes SUPERFISH 7.19 and CST Microwave Studio 2012©. RF characterizations and tunings of the RF-gun were performed to ensure the reliability of the gun operation. The results from 3D simulations and measurements are compared and discussed in this paper. The influence of asymmetric field distributions inside the RF-gun on the electron beam properties was investigated via 3D beam dynamics simulations. A change in the coupling-plane of the side-coupling cavity is suggested to improve the gun performance.

RETROPERITONEAL LYMPH NODE DISSECTION AFTER INDUCTION CHEMOTHERAPY IN METASTATIC TESTICULAR NON-SEMINOMA

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V. B. Matveev

2014-07-01

Full Text Available Objective: to evaluate the outcome of retroperitoneal lymph node dissection (RLND in disseminated testicular non-seminoma patients with residual metastases after induction chemotherapy. Material and methods. The RLND performed in 1983 to 2007 were analyzed in 367 testicular non-seminoma patients with residual retroperitoneal masses after ineffective induction chemotherapy. The median age was 26.06.9 years. Orchidectomy was performed in all patients. Category N1 was regarded in 12 (3.3% patients, N2 in 79 (21.5%, N3 in 238 (64.9%, Nx in 38 (10.4%. Distant metastases were present in 133 (36.2% cases. The baseline tumor marker level was elevated in 328 (89.4% patients (S1 in 169 (46.0%, S2 in 108 (29.4%, S3 in 51 (13.9%, Sx in 39 (10.6%. According to the IGCCCG prognostic model, 149 (40.6% patients were classified as good prognostic group, 100 (27.2% as moderate, 77 (21.0% as poor ones; the prognostic group was not defined in 41 (11.2% cases who had started treatment at another facility due to data unavailability. After orchifuniculectomy, all patients received induction cisplatin-based chemotherapy which resulted in tumor shrinkage <50% in 70 (19.1%, 51-90% in 166 (45.2%, and >90% - in 29 (7.9% cases. The response was not properly assessed in 102 (27.8% cases. CT scan revealed residual retroperitoneal masses after chemotherapy in all patients (<2 cm - 52 (14.2%, 2-5 cm - 166 (45.2%, >5 cm - 149 (40.6%. The tumor markers level remained elevated following chemotherapy in 70 (19.1% cases. All patients underwent RLND (complete in 295 (80.4% cases. Radical RLND demanded resection of adjacent organs in 22 (5.9% cases. Extraretroperitoneal metastases were removed simultaneously with retroperitoneal tumor in 22 (5.9% patients. Postoperative chemotherapy was administered in 100 (27.2% cases. The median followup was 82.1 (3-188 months. Results. Complications developed in 31 (8.5% of the 367 of patients. Mortality rate was 0.6% (2/367 cases. Resection of

Application of modified R.E.N.A.L. nephrometry score system in evaluating the retroperitoneal partial nephrectomy for T1 renal cell carcinoma.

Science.gov (United States)

Wang, Qinzhang; Qian, Biao; Li, Qiang; Ni, Zhao; Li, Yinglong; Wang, Xinmin

2015-01-01

This study aims to investigate the application of the modified R.E.N.A.L. nephrometry score system in evaluating the operation difficulty of retroperitoneal partial nephrectomy in T1 renal cell carcinoma patients. A total of 52 patients with T1 renal cell carcinoma were enrolled. They all had retroperitoneal partial nephrectomy. Their clinical data was retrospectively analyzed. R.E.N.A.L. nephrometry score system was modified based on the features of retroperitoneal partial nephrectomy. The specificity, sensitivity and Youden index were compared between R.E.N.A.L. nephrometry score system and the modified R.E.N.A.L. nephrometry score system. The effect of the modified R.E.N.A.L. nephrometry score system on perioperative outcomes was analyzed. Three degrees of operation difficulty were defined by the modified R.E.N.A.L. nephrometry score system, which included the low, medium and high degree of operation difficulty. The specificity, sensitivity and Youden index of the modified R.E.N.A.L. nephrometry score system were better than those of the original R.E.N.A.L. nephrometry score system. Compared with low degree of operation difficulty, patients with medium and high degree of operation difficulty had significantly higher levels of operative time, warm ischemia time, and intraoperative blood loss (P system has a good effect in evaluating the operation difficulty of retroperitoneal partial nephrectomy.

Chronic expanding hematoma in the retroperitoneal space: a case report

Science.gov (United States)

2013-01-01

Background Chronic expanding hematoma is a rare condition that develops after surgery, trauma, or injury. It can also develop at any location in the body in the absence of trauma. Clinical findings and various diagnostic imaging modalities can aid in the differential diagnosis of this condition. In general, hematomas are naturally reabsorbed and rarely cause serious problems. However, hematomas that develop slowly without a history of trauma, surgery, or bleeding disorders could be difficult to differentiate from soft tissue neoplasms. In the present case, we describe a patient, without any history or physical evidence of trauma, who exhibited a large chronic expanding hematoma in the retroperitoneal space that resulted in hydronephrosis because of the pressure exerted on the left ureter. Case presentation A 69-year-old man presented to our hospital with a swollen lesion in the left flank. A mass, 19 cm in diameter, was detected in the retroperitoneal space by computed tomography. We suspected the presence of a chronic expanding hematoma, soft tissue tumor, or left renal artery aneurysm. Surgical treatment was performed. However, postoperative histopathological examination indicated that the mass was a nonmalignant chronic expanding hematoma. No recurrence was observed during a 2-year follow-up period. Conclusion In patients without a history of trauma who present slowly growing masses, the differential diagnosis should include chronic expanding hematoma in addition to cysts and soft tissue tumors. Moreover, the use of magnetic resonance imaging and computed tomography is essential to differentiate between chronic expanding hematoma and soft tissue tumors. PMID:24237992

RF characterization and testing of ridge waveguide transitions for RF power couplers

Energy Technology Data Exchange (ETDEWEB)

Kumar, Rajesh; Jose, Mentes; Singh, G.N. [Ion Accelerator Development Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Kumar, Girish [Department of Electrical Engineering, IIT Bombay, Mumbai 400076,India (India); Bhagwat, P.V. [Ion Accelerator Development Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

2016-12-01

RF characterization of rectangular to ridge waveguide transitions for RF power couplers has been carried out by connecting them back to back. Rectangular waveguide to N type adapters are first calibrated by TRL method and then used for RF measurements. Detailed information is obtained about their RF behavior by measurements and full wave simulations. It is shown that the two transitions can be characterized and tuned for required return loss at design frequency of 352.2 MHz. This opens the possibility of testing and conditioning two transitions together on a test bench. Finally, a RF coupler based on these transitions is coupled to an accelerator cavity. The power coupler is successfully tested up to 200 kW, 352.2 MHz with 0.2% duty cycle.

[Multivisceral organ procurement for transplantation derived mobilization maneouvres: very helpful auxiliary techniques in the excision of large retroperitoneal masses].

Science.gov (United States)

González, Javier; Shirodkar, S P; Ciancio, G

2011-04-01

The excision of large retroperitoneal masses poses a challenge for every surgeon. Sometimes the urologist must face situations that do not fit to any conventional approach or technique previously described. Obtaining adequate exposure for safe and oncologically correct management of these masses is based, on many cases, in the mobilization of anatomical adjacent structures to generate a sufficient field in abdominal areas of difficult access. Complex visceral mobilization maneuvers derived from multivisceral transplantation organ procurement surgery provides ancillary techniques that used properly facilitate their successful resolution. The main purpose of this paper is the description of these surgical maneuvers essential to increase both exposure and vascular control in addressing the ever-dreaded high-volume retroperitoneal masses.

Retroperitoneal migration of a self-inflicted ballpoint pen via the urethra

Directory of Open Access Journals (Sweden)

Jose Cury

2006-04-01

Full Text Available Numerous accounts documenting the introduction of foreign bodies into the urinary bladder have been reported. These foreign bodies are typically self-inserted via urethral but migration from adjacent organs by an ulcerative process and penetrating injuries are also reported. However, "contrary" migration of a self-inflicted vesical foreign body to the retroperitoneum was not previously reported in literature. We report here a case of a ballpoint pen self-inserted via urethral by a female patient, which was identified in retroperitoneal position years later.

RF study and 3-D simulations of a side-coupling thermionic RF-gun

Energy Technology Data Exchange (ETDEWEB)

Rimjaem, S., E-mail: sakhorn.rimjaem@cmu.ac.th [Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics (ThEP), Commission on Higher Education, Bangkok 10400 (Thailand); Kusoljariyakul, K.; Thongbai, C. [Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics (ThEP), Commission on Higher Education, Bangkok 10400 (Thailand)

2014-02-01

A thermionic RF-gun for generating ultra-short electron bunches was optimized, developed and used as a source at a linac-based THz radiation research laboratory of the Plasma and Beam Physics Research Facility, Chiang Mai University, Thailand. The RF-gun is a π/2-mode standing wave structure, which consists of two S-band accelerating cells and a side-coupling cavity. The 2856 MHz RF wave is supplied from an S-band klystron to the gun through the waveguide input-port at the cylindrical wall of the second cell. A fraction of the RF power is coupled from the second cell to the first one via a side-coupling cavity. Both the waveguide input-port and the side-coupling cavity lead to an asymmetric geometry of the gun. RF properties and electromagnetic field distributions inside the RF-gun were studied and numerically simulated by using computer codes SUPERFISH 7.19 and CST Microwave Studio 2012{sup ©}. RF characterizations and tunings of the RF-gun were performed to ensure the reliability of the gun operation. The results from 3D simulations and measurements are compared and discussed in this paper. The influence of asymmetric field distributions inside the RF-gun on the electron beam properties was investigated via 3D beam dynamics simulations. A change in the coupling-plane of the side-coupling cavity is suggested to improve the gun performance.

The RF Design of an HOM Polarized RF Gun for the ILC

International Nuclear Information System (INIS)

Wang, J.W.; Clendenin, J.E.; Colby, E.R.; Miller, R.A.; Lewellen, J.W.

2006-01-01

The ILC requires a polarized electron beam. While a highly polarized beam can be produced by a GaAs-type cathode in a DC gun of the type currently in use at SLAC, JLAB and elsewhere, the ILC injector system can be simplified and made more efficient if a GaAs-type cathode can be combined with a low emittance RF gun. Since this type of cathode is known to be extremely sensitive to vacuum contamination including back bombardment by electrons and ions, any successful polarized RF gun must have a significantly improved operating vacuum compared to existing RF guns. We present a new RF design for an L-Band normal conducting (NC) RF gun for the ILC polarized electron source. This design incorporates a higher order mode (HOM) structure, whose chief virtue in this application is an improved conductance for vacuum pumping on the cathode. Computer simulation models have been used to optimize the RF parameters with two principal goals: first to minimize the required RF power; second to reduce the peak surface field relative to the field at the cathode in order to suppress field emitted electron bombardment. The beam properties have been simulated initially using PARMELA. Vacuum and other practical issues for implementing this design are discussed

Accurate modeling of complete functional RF blocks: CHAMELEON RF

NARCIS (Netherlands)

Janssen, H.H.J.M.; Niehof, J.; Schilders, W.H.A.; Ciuprina, G.; Ioan, D.

2007-01-01

Next-generation nano-scale RF-IC designs have an unprecedented complexity and performance that will inevitably lead to costly re-spins and loss of market opportunities. In order to cope with this, the aim of the European Framework 6 CHAMELEON RF project is to develop methodologies and prototype

RF MEMS

Indian Academy of Sciences (India)

At the bare die level the insertion loss, return loss and the isolation ... ing and packaging of a silicon on glass based RF MEMS switch fabricated using DRIE. ..... follows the power law based on the asperity deformation model given by Pattona & ... Surface mount style RF packages (SMX series 580465) from Startedge Corp.

Peritoneal Dialysis and Retroperitoneal Laparoscopic Radical Nephrectomy: A Favorable Experience With a Patient Complicated by Renal Cell Carcinoma

Directory of Open Access Journals (Sweden)

Reika Imai

2017-12-01

Full Text Available Peritoneal dialysis (PD is an accepted modality for managing end-stage kidney disease. We herein report a 75-year-old female patient on chronic PD who was complicated by renal cell carcinoma. She was successfully treated with retroperitoneal laparoscopic radical nephrectomy followed by a prompt resumption of the procedure. Various surgeries disturbing the abdominal wall integrity often disrupt the regular PD schedule, and using minimally invasive approaches is therefore an attractive therapeutic option. Our experience emphasizes the feasibility and safety of a retroperitoneal approach–based laparoscopic technique based on several empirical examples. However, systemic studies on this topic are obviously lacking, so we strongly recommend the accumulation of more cases similar to our own. Several surgical concerns that need to be dealt with among PD patients are also discussed.

Adenocarcinomas arising from primary retroperitoneal mature teratomas: CT and MR imaging

International Nuclear Information System (INIS)

Wang, Li-Jen; Wong, Yon-Cheong; Chu, Sheng-Hsien; Ng, Kwai-Fong

2002-01-01

An adenocarcinoma arising from mature teratoma is one form of teratoma with malignant transformation. It is extremely rare but highly malignant. The authors report two patients with adenocarcinomas arising from primary retroperitoneal teratomas. The CT and MRI findings of the tumors are presented with emphasis on imaging features implying the presence of malignant transformation and differing from those of pure benign mature teratoma. Correct diagnosis of the presence of malignant transformation from a benign mature teratoma can be made as early as possible by awareness of the imaging features. (orig.)

Combined management of retroperitoneal sarcoma with dose intensification radiotherapy and resection: Long-term results of a prospective trial.

LENUS (Irish Health Repository)

Smith, Myles J F

2014-01-07

Late failure is a challenging problem following resection of retroperitoneal sarcoma (RPS). We investigated the effects of preoperative XRT plus dose escalation with early postoperative brachytherapy (BT) on long-term survival and recurrence in RPS.

Characteristic performance of radio-frequency(RF) plasma heating using inverter RF power supplies

International Nuclear Information System (INIS)

Imai, Takahiro; Uesugi, Yoshihiko; Takamura, Shuichi; Sawada, Hiroyuki; Hattori, Norifumi

2000-01-01

High heat flux plasma are produced by high powe (∼14 kW) ICRF heating using inverter power supplies in the linear divertor simulator NAGDIS-II. The power flow of radiated rf power is investigated by a calorimetric method. Conventional power calculation using antenna voltage and current gives that about 70% of the rf power is radiated into the plasma. But increase of the heat load at the target and anode is about 10% of the rf power. Through this experiment, we find that about half of the rf power is lost at the antenna surface through the formation of rf induced sheath. And about 30% of the power is lost into the vacuum vessel through the charge exchange and elastic collision of ions with neutrals. (author)

Simulations of S-band RF gun with RF beam control

Science.gov (United States)

Barnyakov, A. M.; Levichev, A. E.; Maltseva, M. V.; Nikiforov, D. A.

2017-08-01

The RF gun with RF control is discussed. It is based on the RF triode and two kinds of the cavities. The first cavity is a coaxial cavity with cathode-grid assembly where beam bunches are formed, the second one is an accelerating cavity. The features of such a gun are the following: bunched and relativistic beams in the output of the injector, absence of the back bombarding electrons, low energy spread and short length of the bunches. The scheme of the injector is shown. The electromagnetic field simulation and longitudinal beam dynamics are presented. The possible using of the injector is discussed.

Historical perspectives and future directions in the surgical management of retroperitoneal sarcoma.

Science.gov (United States)

Tseng, William W; Seo, Hyun Jae; Pollock, Raphael E; Gronchi, Alessandro

2018-01-01

Retroperitoneal sarcomas (RPS) have fascinated and intrigued physicians both past and present. Operative mortality rates were historically very high and complete resection was not possible for the majority of patients until only the last 2 decades. More recently, changes to the surgical approach and clinical decision-making in RPS have improved patient outcomes. With select integration of nonsurgical therapies, continued RPS-specific research, and ongoing collaborative efforts among major referral centers, the future appears promising. © 2017 Wiley Periodicals, Inc.

Rare Variants in Genes Encoding MuRF1 and MuRF2 Are Modifiers of Hypertrophic Cardiomyopathy

Directory of Open Access Journals (Sweden)

Ming Su

2014-05-01

Full Text Available Modifier genes contribute to the diverse clinical manifestations of hypertrophic cardiomyopathy (HCM, but are still largely unknown. Muscle ring finger (MuRF proteins are a class of muscle-specific ubiquitin E3-ligases that appear to modulate cardiac mass and function by regulating the ubiquitin-proteasome system. In this study we screened all the three members of the MuRF family, MuRF1, MuRF2 and MuRF3, in 594 unrelated HCM patients and 307 healthy controls by targeted resequencing. Identified rare variants were confirmed by capillary Sanger sequencing. The prevalence of rare variants in both MuRF1 and MuRF2 in HCM patients was higher than that in control subjects (MuRF1 13/594 (2.2% vs. 1/307 (0.3%, p = 0.04; MuRF2 22/594 (3.7% vs. 2/307 (0.7%; p = 0.007. Patients with rare variants in MuRF1 or MuRF2 were younger (p = 0.04 and had greater maximum left ventricular wall thickness (p = 0.006 than those without such variants. Mutations in genes encoding sarcomere proteins were present in 19 (55.9% of the 34 HCM patients with rare variants in MuRF1 and MuRF2. These data strongly supported that rare variants in MuRF1 and MuRF2 are associated with higher penetrance and more severe clinical manifestations of HCM. The findings suggest that dysregulation of the ubiquitin-proteasome system contributes to the pathogenesis of HCM.

rf impedance of the accelerating beam gap and its significance to the TRIUMF rf system

International Nuclear Information System (INIS)

Poirier, R.

1979-03-01

The rf system at TRIUMF is now operating with the highest Q, the lowest rf leakage into the beam gap, the best voltage stability, and the lowest resonator strongback temperatures ever measured since it was first put into operation. This paper describes the calculation of the rf impedance of the beam gap and its correlation to the rf problems encountered, which eventually led to modifications to the flux guides and resonator tips to accomplish the improved operation of the rf system

Positron emission tomography in patients with aggressive fibromatosis/desmoid tumours undergoing therapy with imatinib

Energy Technology Data Exchange (ETDEWEB)

Kasper, Bernd; Hohenberger, Peter [University of Heidelberg, Sarcoma Unit, ITM - Interdisciplinary Tumor Center Mannheim, Mannheim University Medical Center, Mannheim (Germany); Dimitrakopoulou-Strauss, Antonia; Strauss, Ludwig G. [German Cancer Research Center, Clinical Cooperation Unit Nuclear Medicine, Heidelberg (Germany)

2010-10-15

We used {sup 18}F-FDG PET to evaluate the FDG uptake in patients with aggressive fibromatosis (AF, also known as desmoid tumours) undergoing therapy with imatinib (imatinib mesylate, Glivec). The pilot study included nine patients with progressive AF receiving oral treatment with imatinib at a daily dose of 800 mg. Patients were examined using PET prior to the start of therapy and during imatinib treatment. Restaging according to the Response Evaluation Criteria in Solid Tumors (RECIST) was performed in parallel using CT and/or MRI and served as reference. The clinical outcomes in nine evaluable patients were as follows: seven patients with stable disease, and two patients with progressive disease. A 27% decrease in the median average standardized uptake value (SUV) of the sequential PET examinations was demonstrated in all evaluable patients with three patients (33%) showing a decrease in SUV of more than 40% (48%, 52% and 54%, respectively); no patient showed a substantial increase in SUV. To our knowledge, this is the first series of AF patients undergoing treatment with imatinib and monitored using sequential PET imaging, that allows detection of SUV changes after imatinib induction, thus helping to decide whether treatment should be continued or not. (orig.)

Fast access and early ligation of the renal pedicle significantly facilitates retroperitoneal laparoscopic radical nephrectomy procedures: modified laparoscopic radical nephrectomy

Directory of Open Access Journals (Sweden)

Yang Qing

2013-01-01

Full Text Available Abstract Background The objective of this study was to develop a modified retroperitoneal laparoscopic nephrectomy and compare its results with the previous technique. Methods One hundred retroperitoneal laparoscopic nephrectomies were performed from February 2007 to October 2011. The previous technique was performed in 60 cases (Group 1. The modified technique (n = 40 included fast access to the renal pedicle according to several anatomic landmarks and early ligation of renal vessels (Group 2. The mean operation time, mean blood loss, duration of hospital stay conversion rate and complication rate were compared between the groups. Results No significant differences were detected regarding mean patient age, mean body mass index, and tumor size between the two groups (P >0.05. The mean operation time was 59.5 ± 20.0 and 39.5 ± 17.5 minutes, respectively, in Groups 1 and 2 (P P P >0.05. Conclusions Early ligature using fast access to the renal vessels during retroperitoneal laparoscopic radical nephrectomy contributed to less operation time and intraoperative blood loss compared with the previous technique. In addition, the modified technique permits the procedure to be performed following the principles of open radical nephrectomy.

Retroperitoneal Mass Masquerading as Failure to Thrive in a 91-year-old Woman.

Science.gov (United States)

Ologun, Gabriel O; Yarze, Noel; Bertsch, David; Mwesige, Joseph

2017-11-08

Failure to thrive (FTT) is a state of overall decline. Patients often present with weight loss, poor appetite, malnutrition, and decreased physical functioning. The etiology is multifactorial including chronic diseases, functional impairments, and acute illnesses. Evaluation for reversible causes is paramount, and treatment is aimed at maintaining or improving functional status. We present a case of a 91-year-old woman with a retroperitoneal mass that was found on workup for failure to thrive.

Primary Cyst adenocarcinoma: exceptional etiology of a retroperitoneal cystic tumor.First National Communication

International Nuclear Information System (INIS)

Gonzalez, D.; Ruso, L.; Ettlin, A.

2010-01-01

This work is about the clinical case of a 29 year old patient who consulted for right lank pain, where a tumor was identified. Ultrasound confirmed the existence of a cystic process, and complete surgical abscission/exeresis was performed next to an area in the in the abdominal wall. Anatomopathological report confirmed a primary retroperitoneal cistoadenocarcinoma. No adjuvant treatment was applied, evolution was good 11 months after surgery, no evidence of the disease

Microfluidic stretchable RF electronics.

Science.gov (United States)

Cheng, Shi; Wu, Zhigang

2010-12-07

Stretchable electronics is a revolutionary technology that will potentially create a world of radically different electronic devices and systems that open up an entirely new spectrum of possibilities. This article proposes a microfluidic based solution for stretchable radio frequency (RF) electronics, using hybrid integration of active circuits assembled on flex foils and liquid alloy passive structures embedded in elastic substrates, e.g. polydimethylsiloxane (PDMS). This concept was employed to implement a 900 MHz stretchable RF radiation sensor, consisting of a large area elastic antenna and a cluster of conventional rigid components for RF power detection. The integrated radiation sensor except the power supply was fully embedded in a thin elastomeric substrate. Good electrical performance of the standalone stretchable antenna as well as the RF power detection sub-module was verified by experiments. The sensor successfully detected the RF radiation over 5 m distance in the system demonstration. Experiments on two-dimensional (2D) stretching up to 15%, folding and twisting of the demonstrated sensor were also carried out. Despite the integrated device was severely deformed, no failure in RF radiation sensing was observed in the tests. This technique illuminates a promising route of realizing stretchable and foldable large area integrated RF electronics that are of great interest to a variety of applications like wearable computing, health monitoring, medical diagnostics, and curvilinear electronics.

[DESCRIPTION OF A RETROPERITONEAL ACCESS ROUTE TO THE VESSELS OF THE SPLEEN FOR SPLENORENAL ARTERIAL AND VENOUS ANASTOMOSIS].

Science.gov (United States)

Gil-Vernet Vila, José María

2014-01-01

To perform arterial or venous spleno-renal anastomoses, surgeons have so far systematically used the transperitoneal way whic is burdened by a high mortality an morbility percentage. On the basis of anatomo-surgical considerations, a retroperitoneal approach has been found reaching the hilus of the spleen via the lumbar region; the first arterial spleno-renal anastomosis by this way was performed in 1972 and the first venous spleno-renal anastomosis due to portal hipertension also by this way was performed in 1974, the alter proving to be the least aggresive by avoiding damaging the páncreas, the most surgical and direct for reaching the splenic vessels thereby enabling a better exposure and an easier performing of the anastomoses. By being retroperitoneal, the loss or infección of the ascitic liquid in the cirrhotic patient is prevented.

Rf and space-charge induced emittances in laser-driven rf guns

International Nuclear Information System (INIS)

Kim, Kwang-Je; Chen, Yu-Jiuan.

1988-10-01

Laser-driven rf electron guns are potential sources of high-current, low-emittance, short bunch-length electron beams, which are required for many advanced accelerator applications, such as free-electron lasers and injectors for high-energy machines. In such guns the design of which was pioneered at Los Alamos National Laboratory and which is currently being developed at several other laboratories, a high-power laser beam illuminates a photo-cathode surface placed on an end wall of an rf cavity. The main advantages of this type of gun are that the time structure of the electron beam is controlled by the laser, eliminating the need for bunchers, and that the electric field in rf cavities can be made very strong, so that the effects due to space-charge repulsion can be minimized. In this paper, we present an approximate but simple analysis for the transverse and longitudinal emittances in rf guns that takes into account both the time variation of the rf field and the space-charge effect. The results are compared and found to agree well with those from simulation. 7 refs., 6 figs

Barrier rf systems in synchrotrons

International Nuclear Information System (INIS)

Bhat, Chandra M.

2004-01-01

Recently, many interesting applications of the barrier RF system in hadron synchrotrons have been realized. A remarkable example of this is the development of longitudinal momentum mining and implementation at the Fermilab Recycler for extraction of low emittance pbars for the Tevatron shots. At Fermilab, we have barrier RF systems in four different rings. In the case of Recycler Ring, all of the rf manipulations are carried out using a barrier RF system. Here, the author reviews various uses of barrier rf systems in particle accelerators including some new schemes for producing intense proton beam and possible new applications

Design of an L-band normally conducting RF gun cavity for high peak and average RF power

Energy Technology Data Exchange (ETDEWEB)

Paramonov, V., E-mail: paramono@inr.ru [Institute for Nuclear Research of Russian Academy of Sciences, 60-th October Anniversary prospect 7a, 117312 Moscow (Russian Federation); Philipp, S. [Deutsches Elektronen-Synchrotron DESY, Platanenallee 6, D-15738 Zeuthen (Germany); Rybakov, I.; Skassyrskaya, A. [Institute for Nuclear Research of Russian Academy of Sciences, 60-th October Anniversary prospect 7a, 117312 Moscow (Russian Federation); Stephan, F. [Deutsches Elektronen-Synchrotron DESY, Platanenallee 6, D-15738 Zeuthen (Germany)

2017-05-11

To provide high quality electron bunches for linear accelerators used in free electron lasers and particle colliders, RF gun cavities operate with extreme electric fields, resulting in a high pulsed RF power. The main L-band superconducting linacs of such facilities also require a long RF pulse length, resulting in a high average dissipated RF power in the gun cavity. The newly developed cavity based on the proven advantages of the existing DESY RF gun cavities, underwent significant changes. The shape of the cells is optimized to reduce the maximal surface electric field and RF loss power. Furthermore, the cavity is equipped with an RF probe to measure the field amplitude and phase. The elaborated cooling circuit design results in a lower temperature rise on the cavity RF surface and permits higher dissipated RF power. The paper presents the main solutions and results of the cavity design.

Practical RF system design

CERN Document Server

Egan, William F

2003-01-01

he ultimate practical resource for today's RF system design professionals Radio frequency components and circuits form the backbone of today's mobile and satellite communications networks. Consequently, both practicing and aspiring industry professionals need to be able to solve ever more complex problems of RF design. Blending theoretical rigor with a wealth of practical expertise, Practical RF System Design addresses a variety of complex, real-world problems that system engineers are likely to encounter in today's burgeoning communications industry with solutions that are not easily available in the existing literature. The author, an expert in the field of RF module and system design, provides powerful techniques for analyzing real RF systems, with emphasis on some that are currently not well understood. Combining theoretical results and models with examples, he challenges readers to address such practical issues as: * How standing wave ratio affects system gain * How noise on a local oscillator will affec...

Direct RF modulation transmitter, sampling clock frequency setting method for direct RF modulation transmitter

NARCIS (Netherlands)

Fukuda, Shuichi; Nauta, Bram

2013-01-01

PROBLEM TO BE SOLVED: To provide a direct RF modulation transmitter capable of satisfying a radiation level regulation even without providing a SAW filter. SOLUTION: A direct RF modulation transmitter includes: digital/RF converters 105, 106 to which an I digital baseband signal, a Q digital

Direct RF modulation transmitter, sampling clock frequency setting method for direct RF modulation transmitter

NARCIS (Netherlands)

Fukuda, Shuichi; Nauta, Bram

2014-01-01

PROBLEM TO BE SOLVED: To provide a direct RF modulation transmitter capable of satisfying a radiation level regulation even without providing a SAW filter. SOLUTION: A direct RF modulation transmitter includes: digital/RF converters 105, 106 to which an I digital baseband signal, a Q digital

Lymphatic endothelial cell line (CH3) from a recurrent retroperitoneal lymphangioma.

Science.gov (United States)

Way, D; Hendrix, M; Witte, M; Witte, C; Nagle, R; Davis, J

1987-09-01

An endothelial cell line derived from a massive recurrent chyle-containing retroperitoneal lymphangioma was isolated in monolayer culture. Scanning and transmission electron microscopy and immunohistochemistry confirmed a close resemblance to blood vascular endothelium with typical cobblestone morphology, positive immunofluorescence staining for endothelial marker Factor VIII-associated antigen and fibronectin, and prominent Weibel-Palade bodies. The endothelial cells also exhibited other ultrastructural features characteristic of lymphatic endothelium, including sparse microvillous surface projections, overlapping intercellular junctions, and abundant intermediate filaments. This endothelial cell line represents a new source of proliferating lymphatic endothelium for future study, including structural and functional comparison to blood vascular endothelium.

RF feedback for KEKB

Energy Technology Data Exchange (ETDEWEB)

Ezura, Eizi; Yoshimoto, Shin-ichi; Akai, Kazunori [National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan)

1996-08-01

This paper describes the present status of the RF feedback development for the KEK B-Factory (KEKB). A preliminary experiment concerning the RF feedback using a parallel comb-filter was performed through a choke-mode cavity and a klystron. The RF feedback has been tested using the beam of the TRISTAN Main Ring, and has proved to be effective in damping the beam instability. (author)

Intraduodenal sarcoma recurrence of retroperitoneal origin: an unusual cause for a duodenal obstruction

Directory of Open Access Journals (Sweden)

Bao Jean J

2012-04-01

Full Text Available Abstract Soft tissue sarcomas are uncommon tumors, and intraduodenal soft tissue sarcoma manifestation is even more rare. Only three cases of intraduodenal sarcomas have been reported in the literature thus far. Here, we report a case of an intraduodenal recurrence of a retroperitoneal sarcoma causing bowel obstruction. This unusual recurrence pattern likely relates to the patient’s previous resection and radiation treatment, and highlights the benefits, limitations and follow-up strategies after multimodality treatment.

Multispeciality Approach in the Management of Patient with Hereditary Gingival Fibromatosis: 1-Year Followup: A Case Report

Directory of Open Access Journals (Sweden)

T. Ramakrishnan

2010-01-01

Full Text Available Background. Hereditary gingival fibromatosis is a fibrotic enlargement of the gingiva. It may exist as an isolated abnormality or as part of multisystem syndrome. This paper reports a case of 16-year-old male with generalized severe gingival overgrowth, involving the maxillary and mandibular arches and covering almost all teeth. Methods. Periodontal management of gingival enlargement included gingivectomy in both arches except in the lower right molar region where flap surgery was done under general anesthesia. After a 2-month followup period, orthodontic treatment was started with fixed appliances. Monthly periodontal checkups and maintainance (scaling and polishing were scheduled to control the gingival inflammation. Results. Reevaluation of the patient of surgical treatment after two months did not show any recurrence of condition; however, minimal overgrowth was noted 1 month after the beginning of orthodontic treatment which was treated nonsurgically. Conclusions. Although the risk of recurrence is high with this condition, surgical treatment with correction of malocclusion and regular followup can provide excellent outcome as seen in this case.

Characterization and management of patients with retroperitoneal sarcoma, Hospital San Juan de Dios 2007-2012

International Nuclear Information System (INIS)

Batista Rodriguez, Gabriela

2013-01-01

Patients diagnosed with retroperitoneal sarcoma at the Hospital San Juan de Dios were characterized during the years 2007 to 2012. The population framework was taken from the hospital's Pathology service database. A total of 15 patients older than 12 years with a diagnosis of sarcoma or malignant fibrous histiocytoma and that the site of origin of the biopsy was the retroperitoneum were selected. The data of the selected patients were collected through a data collection form. The variables included were: age, sex, origin, dates of importance (income, discharge, surgery, complication), presence and type of complications, pathological staging, type of surgery, comorbidities, presence and date of recurrence, treatment with chemotherapy and radiotherapy, death and causes of death. A descriptive analysis with the calculation of frequency measurements (absolute and relative) was carried out to describe the occurrence of the event. The analysis of proportional risks was performed considering the relationship between death and time, the possible relationship with the service of approach, clinical stage and resection status was also assessed. Information on diagnosis, evaluation, staging and management of retroperitoneal sarcomas is cited in the theoretical framework [es

Versatile rf controller

International Nuclear Information System (INIS)

Howard, D.

1985-05-01

The low level rf system developed for the new Bevatron local injector provides precise control and regulation of the rf phase and amplitude for three 200 MHz linac cavities. The main features of the system are: extensive use of inexpensive, off-the-shelf components, ease of maintenance, and adaptability to a wide range of operation frequencies. The system utilizes separate function, easily removed rf printed circuit cards interconnected via the edge connectors. Control and monitoring are available both locally and through the computer. This paper will describe these features as well as the few component changes that would be required to adapt the techniques to other operating frequencies. 2 refs

Retroperitoneal Paraganglioma – a rare cause of arterial hypertension

Directory of Open Access Journals (Sweden)

Isabel Silva

2017-03-01

Full Text Available Paragangliomas are rare neuroendocrine tumours, most commonly found in adults. These differ from pheochromocytomas in that their location is extra-adrenal, and they are responsible for about 1% of arterial hypertension aetiologies. We report the case of a 30-year-old female whose past medical history was unremarkable. However, her arterial hypertension led to further examination in search of secondary aetiologies, in which a retroperitoneal mass and an increase in levels of catecholamines were detected; findings that led to the final diagnosis of paraganglioma. A multidisciplinary team, whose approach was to use pharmacological alpha-adrenergic blocking agents and a surgical resection of the lesion, treated the patient. The patient is clinically well but will continue to be monitored as an outpatient, and genetic testing is being encouraged.

Giant kidney worm (Dioctophyma renale) infection mimicking retroperitoneal neoplasm.

Science.gov (United States)

Sun, T; Turnbull, A; Lieberman, P H; Sternberg, S S

1986-07-01

A 50-year-old Chinese man was found by ultrasound and computed tomography to have a retroperitoneal mass in the right upper quadrant of the abdomen. At operation, a hemorrhagic cyst was detected at the upper pole of the right kidney adjacent to the adrenal gland. Microscopic examination revealed that the cyst wall was composed of granulomatous tissue loaded with eggs and cross-sections of parasites, identified as Dioctophyma renale. The eggs were characterized by a birefringent striated double wall. The presence of cross sections of adult worms of D. renale in human tissue has not been previously described. Another unique feature of this case was that the right kidney was intact, as examined grossly at laparotomy and by intravenous pyelography. Eggs were not detected in the urine.

Extraosseous Multiple Myeloma with Retroperitoneal Manifestation: A Case Report

International Nuclear Information System (INIS)

Berdugo, Juan Oswaldo; Nieto, Sonia Janeth; Garzon, Julian Gonzalo

2008-01-01

This paper presents a case of a 57 years old man (patient of Hospital Militar Central of Bogota, Colombia) with weight loss and a mass in the right clavicle. Plain film radiography shows a lytic lesion in the sternum side of the clavicle. biopsy reports a plasmacytomas, radiotherapy was performed. Three years later lesions of similar characteristics within ribs and a focal lesion in left testicle were detected. The diagnosis was multiple myeloma, Chemotherapy and orquidectomy were performed. One year after, patient complained of diffuse abdominal pain and loss weight, contrast abdominal CT was performed. Computed tomography showed a left heterogeneous mass with irregular contours that involved the retroperitoneal space occupying its three compartments. Biopsy was performed and reported pleomorphicplasmocytic proliferation with nuclear enlargement and hyperchromic nuclei consistent with multiple myeloma with abdominal involvement.

Solitary Bone Plasmacytoma Progressing into Retroperitoneal Plasma Cell Myeloma with No Related End Organ or Tissue Impairment: A Case Report and Review of the Literature

Directory of Open Access Journals (Sweden)

Gargi Tikku

2014-09-01

Full Text Available Solitary bone plasmacytomas and plasma cell myeloma are clonal proliferations of plasma cells. Many patients with solitary bone plasmacytomas develop plasma cell myeloma on follow-up. We present a case of a 70-year-old man who presented with fracture and a lytic lesion in the subtrochanteric region of the left femur and was assigned a diagnosis of solitary bone plasmacytoma. He received local curative radiotherapy. However, 4 months later his serum M protein and β2-microglobulin levels increased to 2.31 g/dL and 5.965 mg/L, respectively. He complained of abdominal fullness and constipation. Ultrasound and non-contrast CT imaging revealed multiple retroperitoneal masses. Colonoscopic examination was normal. Biopsy of the a retroperitoneal mass confirmed it to be a plasmacytoma. Repeat hemogram, blood urea, serum creatinine, skeletal survey, and bone marrow examination revealed no abnormalities. This is an unusual presentation of plasma cell myeloma, which manifested as multiple huge extramedullary retroperitoneal masses and arose from a solitary bone plasmacytoma, without related end organ or tissue impairment and bone marrow plasmacytosis. The patient succumbed to his disease 8 months after the appearance of the retroperitoneal masses. This case highlights the importance of close monitoring of patients diagnosed with solitary bone plasmacytoma with increased serum M protein and serum β2-microglobulin levels, so that early therapy can be instituted to prevent conversion to plasma cell myeloma.

RF Energy Compressor

International Nuclear Information System (INIS)

Farkas, Z.D.

1980-02-01

The RF Energy Compressor, REC described here, transforms cw rf into periodic pulses using an energy storage cavity, ESC, whose charging is controlled by 180 0 bi-phase modulation, PSK, and external Q switching, βs. Compression efficiency, C/sub e/, of 100% can be approached at any compression factor C/sub f/

Completely Isolated Retroperitoneal Enteric Duplication Cyst with Adenocarcinoma Transformation Managed with Robotic Radical Nephrectomy

OpenAIRE

Faraj, Kassem; Edwards, Luke; Gupta, Alia; Seifman, Brian

2017-01-01

Abstract Background: Enteric duplication cysts are congenital malformations that typically affect children in infancy, but can also affect adults. Rarely, these cysts can be complicated by malignancy. We present the first case of retroperitoneal duplication cyst that was complicated by malignancy transformation and managed by robot-assisted excision. Case presentation: A 64-year-old female with a history of a left-sided renal cyst presented with a 4-month history of abdominal pain and fatigue...

Tunable Q-Factor RF Cavity

Energy Technology Data Exchange (ETDEWEB)

Balcazar, Mario D. [Fermilab; Yonehara, Katsuya [Fermilab; Moretti, Alfred [Fermilab; Kazakevitch, Gregory [Fermilab

2018-01-01

Intense neutrino beam is a unique probe for researching beyond the standard model. Fermilab is the main institution to produce the most powerful and widespectrum neutrino beam. From that respective, a radiation robust beam diagnostic system is a critical element in order to maintain the quality of the neutrino beam. Within this context, a novel radiation-resistive beam profile monitor based on a gasfilled RF cavity is proposed. The goal of this measurement is to study a tunable Qfactor RF cavity to determine the accuracy of the RF signal as a function of the quality factor. Specifically, measurement error of the Q-factor in the RF calibration is investigated. Then, the RF system will be improved to minimize signal error.

Diagnostic Value of Multislice Computed Tomography and Magnetic Resonance Imaging in the Diagnosis of Retroperitoneal Spread of Testicular Cancer: A Literature Review

International Nuclear Information System (INIS)

Hansen, J.; Jurik, A.G.

2009-01-01

Testicular cancer is the most frequent malignant disorder in men aged 15-35 years. Generally, diagnosing and follow-up include computer tomography (CT) examinations to detect possible retroperitoneal spread (abdomen and pelvis), resulting in at least eight CT examinations. This patient group is thereby exposed to a non-neglectable radiation dose, increasing the risk of future radiation-induced secondary cancer. This is especially problematic in potentially surgically cured patients with stage 1 testicular cancer. Thus, it can be beneficial to substitute CT with magnetic resonance imaging (MRI), provided there is valid evidence that the diagnostic value of MRI is at least comparable to current multislice CT (MSCT). The purpose of this study was to analyze whether there is evidence to recommend a substitution of MSCT with MRI in the diagnosis of retroperitoneal spread of testicular cancer. A literature search on the diagnostic accuracy, specificity, and sensitivity of MSCT and MRI in the diagnosis of retroperitoneal spread of testicular cancer was performed in the following databases: PubMed, EmBase, and ISI Web of Science. The search was limited to include the period from 2000 to September 2008, and to human and English-language publications. Forty-four publications were obtained for formal review (27 from PubMed, 15 from EmBase, two from ISI Web of Science). None of the publications reviewed encompassed diagnostic specificity and sensitivity of MSCT, and they lacked systematic comparison of MSCT and MRI. Only one study included sensitivity and specificity of MRI compared to single-slice CT. Both methods had a sensitivity and a specificity of approximately 70%. The literature review did not reveal valid data regarding diagnostic accuracy of MRI compared with MSCT for diagnosing retroperitoneal spread of testicular cancer. A prospective blinded comparative study is needed to provide valid evidence

Diagnostic Value of Multislice Computed Tomography and Magnetic Resonance Imaging in the Diagnosis of Retroperitoneal Spread of Testicular Cancer: A Literature Review

Energy Technology Data Exchange (ETDEWEB)

Hansen, J. (Dept. of Medical Physics, Aarhus Univ. Hospital, Aarhus Sygehus, Aarhus (Denmark)); Jurik, A.G. (Dept. of Radiology, Aarhus Univ. Hospital, Aarhus Sygehus, Aarhus (Denmark))

2009-11-15

Testicular cancer is the most frequent malignant disorder in men aged 15-35 years. Generally, diagnosing and follow-up include computer tomography (CT) examinations to detect possible retroperitoneal spread (abdomen and pelvis), resulting in at least eight CT examinations. This patient group is thereby exposed to a non-neglectable radiation dose, increasing the risk of future radiation-induced secondary cancer. This is especially problematic in potentially surgically cured patients with stage 1 testicular cancer. Thus, it can be beneficial to substitute CT with magnetic resonance imaging (MRI), provided there is valid evidence that the diagnostic value of MRI is at least comparable to current multislice CT (MSCT). The purpose of this study was to analyze whether there is evidence to recommend a substitution of MSCT with MRI in the diagnosis of retroperitoneal spread of testicular cancer. A literature search on the diagnostic accuracy, specificity, and sensitivity of MSCT and MRI in the diagnosis of retroperitoneal spread of testicular cancer was performed in the following databases: PubMed, EmBase, and ISI Web of Science. The search was limited to include the period from 2000 to September 2008, and to human and English-language publications. Forty-four publications were obtained for formal review (27 from PubMed, 15 from EmBase, two from ISI Web of Science). None of the publications reviewed encompassed diagnostic specificity and sensitivity of MSCT, and they lacked systematic comparison of MSCT and MRI. Only one study included sensitivity and specificity of MRI compared to single-slice CT. Both methods had a sensitivity and a specificity of approximately 70%. The literature review did not reveal valid data regarding diagnostic accuracy of MRI compared with MSCT for diagnosing retroperitoneal spread of testicular cancer. A prospective blinded comparative study is needed to provide valid evidence

RF guns: a review

International Nuclear Information System (INIS)

Travier, C.

1990-06-01

Free Electron Lasers and future linear colliders require very bright electron beams. Conventional injectors made of DC guns and RF bunchers have intrinsic limitations. The recently proposed RF guns have already proven their capability to produce bright beams. The necessary effort to improve further these performances and to gain reliability is now undertaken by many laboratories. More than twenty RF gun projects both thermionic and laser-driven are reviewed. Their specific characteristics are outlined and their nominal performances are given

Measured performance of the GTA rf systems

International Nuclear Information System (INIS)

Denney, P.M.; Jachim, S.P.

1993-01-01

This paper describes the performance of the RF systems on the Ground Test Accelerator (GTA). The RF system architecture is briefly described. Among the RF performance results presented are RF field flatness and stability, amplitude and phase control resolution, and control system bandwidth and stability. The rejection by the RF systems of beam-induced disturbances, such as transients and noise, are analyzed. The observed responses are also compared to computer-based simulations of the RF systems for validation

Rf system specifications for a linear accelerator

International Nuclear Information System (INIS)

Young, A.; Eaton, L.E.

1992-01-01

A linear accelerator contains many systems; however, the most complex and costly is the RF system. The goal of an RF system is usually simply stated as maintaining the phase and amplitude of the RF signal within a given tolerance to accelerate the charged particle beam. An RF system that drives a linear accelerator needs a complete system specification, which should contain specifications for all the subsystems (i.e., high-power RF, low-level RF, RF generation/distribution, and automation control). This paper defines a format for the specifications of these subsystems and discusses each RF subsystem independently to provide a comprehensive understanding of the function of each subsystem. This paper concludes with an example of a specification spreadsheet allowing one to input the specifications of a subsystem. Thus, some fundamental parameters (i.e., the cost and size) of the RF system can be determined

Functional adrenal cortex preservation: A good reason for posterior retroperitoneal endoscopic approach.

Science.gov (United States)

Vidal, Óscar; Delgado-Oliver, Eduardo; Díaz Del Gobbo, Rafael; Hanzu, Felicia; Squarcia, Mattia; Martínez, Daniel; Fuster, David; Fondevila, Constantino

2018-05-24

Cortical-sparing adrenalectomy is a suitable treatment for hereditary and sporadic bilateral pheochromocytoma, in cases of low risk of malignancy, to reduce the possibility of adrenal insufficiency assuming the chance of local recurrence. The aim of the study is to analyze the functional results of partial adrenalectomy by retroperitoneal endoscopic approach in single-adrenal patients or patients requiring bilateral adrenalectomy. Prospective study between January 2015 and February 2016 including pheochromocytoma patients diagnosed with low risk of malignant mutations. All patients agreed to be included in the study. Experienced endocrine surgeons who have been trained in minimally invasive endocrine surgery performed the procedure using the same surgical technique. Demographic variables and clinical characteristics were collected, subsequently carrying out the descriptive analysis of the data. A total of 6 patients were registered, four associated with MEN type 2 syndrome and two in the context of VHL syndrome. Retroperitoneoscopic resection was performed without laparoscopic or open conversion and no postoperative complications; the average hospital stay was 2.5 days. Preservation of the functional cortex without corticosteroids was achieved in 5 (83%) of out 6 cases with a follow-up of 26.2 ± 6 months. Today, these 5 patients have a preserved adrenal function without hormone replacement. Cortical-sparing adrenalectomy by the retroperitoneal endoscopic approach, in expert hands, is safe and feasible for the treatment of hereditary and sporadic pheochromocytoma in a context of low malignancy, making it possible to avoid the need for corticoid replacement in most cases. Copyright © 2018 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

High time resolution beam-based measurement of the rf-to-laser jitter in a photocathode rf gun

Directory of Open Access Journals (Sweden)

Zhen Zhang

2014-03-01

Full Text Available Characterizing the rf-to-laser jitter in the photocathode rf gun and its possible origins is important for improving the synchronization and beam quality of the linac based on the photocathode rf gun. A new method based on the rf compression effect in the photocathode rf gun is proposed to measure the rf-to-laser jitter in the gun. By taking advantage of the correlation between the rf compression and the laser injection phase, the error caused by the jitter of the accelerating field in the gun is minimized and thus 10 fs time resolution is expected. Experimental demonstration at the Tsinghua Thomson scattering x-ray source with a time resolution better than 35 fs is reported in this paper. The experimental results are successfully used to obtain information on the possible cause of the jitter and the accompanying drifts.

Serum LH-RF and LH levels after synthetic LH-RF administration in man as measured by radioimmunoassays

International Nuclear Information System (INIS)

Shiina, Masaki; Makino, Tsunehisa; Nakamura, Yukio; Iizuka, Rihachi

1975-01-01

Using a radioimmunoassay (RIA) which is sensitive and highly specific to lutenizing hormone releasing factors (LRF, LH-RF), diminution of an exogeously administered synthetic LH-RF in the blood and the movement of LH released into the blood from the anterior lobe of hypopysis were examined on healthy adult males. The blood LH-RF level after an intravenous administration of 200 μg of synthetic LH-RF reached a maximum (mean, 35.0 ng/ml serum) 2.5 minutes after administration, followed by a rapid decrease, and was as low as 1.0 ng/ml serum 30 minutes after administration. The diminution of the exogenous LH-RF from the blood was rapidest 2.5-15 minutes after administration (t1/2=3.9 minutes) and slowest (t1/2=7.9 minutes) 15-30 minutes after administration. On the other hand, when 200 μg of the synthetic LH-RF was administered intramuscularly, LH-RF appeared only slightly in the blood 2.5 minutes after administration, and the maximum level (10 minutes after administration) was only 1.6 ng/ml serum. It diminished from the blood drawing lenient curve. The blood LH level continued to rise significantly starting 5 minutes after administration of 200 μg of the synthetic LH-RF both in intravenous and intramuscular cases, showing hardly any differences between them. The blood endogenous LH-RF level prior to the synthetic LH-RF administration was below the measurable sensitivity (10 pg/tupe). (Mukohata, S.)

Differentiating retroperitoneal liposarcoma tumors with optical coherence tomography

Science.gov (United States)

Lev, Dina; Baranov, Stepan A.; Carbajal, Esteban F.; Young, Eric D.; Pollock, Raphael E.; Larin, Kirill V.

2011-03-01

Liposarcoma (LS) is a rare and heterogeneous group of malignant mesenchymal neoplasms exhibiting characteristics of adipocytic differentiation. Currently, radical surgical resection represents the most effective and widely used therapy for patients with abdominal/retroperitoneal LS, but the presence of contiguous essential organs, such as the kidney, pancreas, spleen, adrenal glands, esophagus or colon, as well as often reoccurrence of LS in A/RP calls for the enhancement of surgical techniques to minimize resection and avoid LS reoccurrences. Difficulty in detecting the margins of neoplasms due to their affinity to healthy fat tissue accounts for the high reoccurrence of LS within A/RP. Nowadays, the microscopic detection of margins is possible only by use of biopsy, and the minimization of surgical resection of healthy tissues is challenging. In this presentation we'll demonstrate the initial OCT results for the imaging and distinction of LS and normal human fat tissues and clear detection of tumor boundaries.

High-brightness rf linear accelerators

International Nuclear Information System (INIS)

Jameson, R.A.

1986-01-01

The issue of high brightness and its ramifications in linacs driven by radio-frequency fields is discussed. A history of the RF linacs is reviewed briefly. Some current applications are then examined that are driving progress in RF linacs. The physics affecting the brightness of RF linacs is then discussed, followed by the economic feasibility of higher brightness machines

Radical Nephrectomy for Primary Retroperitoneal Liposarcoma Near the Kidney has a Beneficial Effect on Disease-Free Survival.

Science.gov (United States)

Rhu, Jinsoo; Cho, Chan Woo; Lee, Kyo Won; Park, Hyojun; Park, Jae Berm; Choi, Yoon-La; Kim, Sung Joo

2018-01-01

The purpose of this study is to analyze the clinical impact of radical nephrectomy on retroperitoneal liposarcoma near the kidney. Data of patients who underwent surgery for unilateral primary retroperitoneal liposarcoma near the kidney were retrospectively collected. Patients were divided into four groups according to whether they underwent nephrectomy and combined resection of other organs. Kaplan-Meier survival analysis was used to estimate disease-free survival and overall survival. Multivariable Cox analysis was used to analyze factors related to disease-free survival and overall survival. Nephrectomy (HR = 0.260, CI = 0.078-0.873, p = 0.029) had a beneficial effect on disease-free survival, while interaction model of nephrectomy*other organ resection (HR = 4.655, CI = 1.767-12.263, p = 0.002) showed poor disease-free survival. Other organ resection was not related to disease-free survival (HR = 1.543, CI = 0.146-16.251, p = 0.718). Operation method (p = 0.007) and FNCLCC grade (p free survival. While combined organ resection without nephrectomy group (HR = 1.604, CI = 0.167-15.370, p = 0.682) and radical nephrectomy with combined organ resection group (HR = 1.309, CI = 0.448-3.825, p = 0.622) did not show significant difference in disease-free survival from the mass excision only group, radical nephrectomy without combined organ resection group (HR = 0.279, CI = 0.078-0.991, p = 0.048) showed superior disease-free survival. Radical nephrectomy of unilateral primary retroperitoneal liposarcoma near the kidney has a beneficial effect on disease-free survival.

Novel Techniques for Retroperitoneal Implantation of Telemetry Transmitters for Physiologic Monitoring in Gottingen Minipigs (Sus scrofa domesticus)

Science.gov (United States)

2014-12-01

that this procedure permitted effective monitoring of complex physiologic data, including transthoracic impedance, without negatively affecting the...retroperitoneal implantation of the telemetry device permitted effective monitoring of complex physiologic data, including transthoracic impedance...nerve agent and cyanide poisoning in minipigs after intraosseous administration. Ann Emerg Med 60:424–430. 26. Ngawhirunpat T, Opanasopit P

Retroperitoneal extra-adrenal paraganglioma: a rare but important diagnosis.

LENUS (Irish Health Repository)

Ahmad, S

2012-01-31

BACKGROUND: Extra-adrenal paragangliomas of the retroperitonium are infrequently diagnosed. Their malignant behaviour cannot be predicted on initial clinical and histological assessment. These tumours have higher propensity for subsequent metastasis compared with pargangliomas at other sites. AIM: We aim to describe a case report of an incidental finding of left retroperitoneal paraganglioma in a young man who presented with right flank pain. We also aim to emphasize the importance of diagnosis and the malignant potential of these tumours. METHOD: Patient\\'s clinical notes, operative findings, imaging studies and laboratory investigations including histology results were reviewed. A literature search was done to look into the incidence, presentation, follow-up plan and treatment options for these tumours. CONCLUSION: Surgical resection is the only available curative option for extra-adrenal paragangliomas. Metastasis is observed years after surgery, hence long-term follow-up is required.

The Spallation Neutron Source RF Reference System

CERN Document Server

Piller, Maurice; Crofford, Mark; Doolittle, Lawrence; Ma, Hengjie

2005-01-01

The Spallation Neutron Source (SNS) RF Reference System includes the master oscillator (MO), local oscillator(LO) distribution, and Reference RF distribution systems. Coherent low noise Reference RF signals provide the ability to control the phase relationships between the fields in the front-end and linear accelerator (linac) RF cavity structures. The SNS RF Reference System requirements, implementation details, and performance are discussed.

RF radiation safety handbook

International Nuclear Information System (INIS)

Kitchen, Ronald.

1993-01-01

Radio frequency radiation can be dangerous in a number of ways. Hazards include electromagnetic compatibility and interference, electro-explosive vapours and devices, and direct effects on the human body. This book is a general introduction to the sources and nature of RF radiation. It describes the ways in which our current knowledge, based on relevant safety standards, can be used to safeguard people from any harmful effects of RF radiation. The book is designed for people responsible for, or concerned with, safety. This target audience will primarily be radio engineers, but includes those skilled in other disciplines including medicine, chemistry or mechanical engineering. The book covers the problems of RF safety management, including the use of measuring instruments and methods, and a review of current safety standards. The implications for RF design engineers are also examined. (Author)

Pregnant women models analyzed for RF exposure and temperature increase in 3T RF shimmed birdcages.

Science.gov (United States)

Murbach, Manuel; Neufeld, Esra; Samaras, Theodoros; Córcoles, Juan; Robb, Fraser J; Kainz, Wolfgang; Kuster, Niels

2017-05-01

MRI is increasingly used to scan pregnant patients. We investigated the effect of 3 Tesla (T) two-port radiofrequency (RF) shimming in anatomical pregnant women models. RF shimming improves B 1 + uniformity, but may at the same time significantly alter the induced current distribution and result in large changes in both the level and location of the absorbed RF energy. In this study, we evaluated the electrothermal exposure of pregnant women in the third, seventh, and ninth month of gestation at various imaging landmarks in RF body coils, including modes with RF shimming. Although RF shimmed configurations may lower the local RF exposure for the mother, they can increase the thermal load on the fetus. In worst-case configurations, whole-body exposure and local peak temperatures-up to 40.8°C-are equal in fetus and mother. Two-port RF shimming can significantly increase the fetal exposure in pregnant women, requiring further research to derive a very robust safety management. For the time being, restriction to the CP mode, which reduces fetal SAR exposure compared with linear-horizontal polarization modes, may be advisable. Results from this study do not support scanning pregnant patients above the normal operating mode. Magn Reson Med 77:2048-2056, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

Mini-open lateral retroperitoneal lumbar spine approach using psoas muscle retraction technique. Technical report and initial results on six patients.

Science.gov (United States)

Aghayev, Kamran; Vrionis, Frank D

2013-09-01

The main aim of this paper was to report reproducible method of lumbar spine access via a lateral retroperitoneal route. The authors conducted a retrospective analysis of the technical aspects and clinical outcomes of six patients who underwent lateral multilevel retroperitoneal interbody fusion with psoas muscle retraction technique. The main goal was to develop a simple and reproducible technique to avoid injury to the lumbar plexus. Six patients were operated at 15 levels using psoas muscle retraction technique. All patients reported improvement in back pain and radiculopathy after the surgery. The only procedure-related transient complication was weakness and pain on hip flexion that resolved by the first follow-up visit. Psoas retraction technique is a reliable technique for lateral access to the lumbar spine and may avoid some of the complications related to traditional minimally invasive transpsoas approach.

Development of new S-band RF window for stable high-power operation in linear accelerator RF system

Science.gov (United States)

Joo, Youngdo; Lee, Byung-Joon; Kim, Seung-Hwan; Kong, Hyung-Sup; Hwang, Woonha; Roh, Sungjoo; Ryu, Jiwan

2017-09-01

For stable high-power operation, a new RF window is developed in the S-band linear accelerator (Linac) RF systems of the Pohang Light Source-II (PLS-II) and the Pohang Accelerator Laboratory X-ray Free-Electron Laser (PAL-XFEL). The new RF window is designed to mitigate the strength of the electric field at the ceramic disk and also at the waveguide-cavity coupling structure of the conventional RF window. By replacing the pill-box type cavity in the conventional RF window with an overmoded cavity, the electric field component perpendicular to the ceramic disk that caused most of the multipacting breakdowns in the ceramic disk was reduced by an order of magnitude. The reduced electric field at the ceramic disk eliminated the Ti-N coating process on the ceramic surface in the fabrication procedure of the new RF window, preventing the incomplete coating from spoiling the RF transmission and lowering the fabrication cost. The overmoded cavity was coupled with input and output waveguides through dual side-wall coupling irises to reduce the electric field strength at the waveguide-cavity coupling structure and the possibility of mode competitions in the overmoded cavity. A prototype of the new RF window was fabricated and fully tested with the Klystron peak input power, pulse duration and pulse repetition rate of 75 MW, 4.5 μs and 10 Hz, respectively, at the high-power test stand. The first mass-produced new RF window installed in the PLS-II Linac is running in normal operation mode. No fault is reported to date. Plans are being made to install the new RF window to all S-band accelerator RF modules of the PLS-II and PAL-XFEL Linacs. This new RF window may be applied to the output windows of S-band power sources like Klystron as wells as the waveguide windows of accelerator facilities which operate in S-band.

An updated overview of the LEB RF system

International Nuclear Information System (INIS)

Rogers, J.D.; Ferrell, J.H.; Curbow, J.E.; Friedrichs, C.

1992-01-01

Each of the Low Energy Booster (LEB) rf systems consists of the following major subsystems: a vacuum tube final rf amplifier driven by a solid state rf amplifier, a ferrite-tuned rf cavity used to bunch and accelerate the beam, a low-level rf system including rf feedback systems, a computer-based supervisory control system, and associated power supplies. The LEB rf system is broadband with the exception of the rf cavity, which is electronically tuned from approximately 47.5 MHz to 59.7 MHz in 50 ms. The design and development status of the LEB rf system is presented, with particular emphasis on the cavity and tuner, and the tuner bias power supply

Predictors of viable germ cell tumor in postchemotherapeutic residual retroperitoneal masses

Directory of Open Access Journals (Sweden)

Khalid Al Othman

2014-01-01

Full Text Available Objective: The aim of this study was to identify predictors of viable germ cell tumor (GCT in postchemotherapeutic residual retroperitoneal masses. Materials and Methods: The pertinent clinical and pathologic data of 16 male patients who underwent postchemotherapeutic retroperitoneal lymph node dissection (PC-RPLND at King Faisal Specialist Hospital and Research Centre between 1994 and 2005 were reviewed retrospectively. It was found that all patients received cisplatin-based chemotherapy for advanced testicular GCT. Results: Out of the 16 male patients, 2 (13%, 8 (50%, and 6 (37% had viable GCT, fibrosis, and teratoma, respectively. Ten (10 of the patients with prechemotherapeutic S1 tumor markers did not have viable GCT, and two of the six patients who had prechemotherapeutic S2 tumor markers have viable GCT. All tumor marker levels normalized after chemotherapy even in patients with viable GCT. Four patients had vascular invasion without viable GCT. Furthermore, four patients had more than 60% embryonal elements in the original pathology, but only 1 had viable GCT at PC-RPLND. Four of the five patients with immature teratoma had teratoma at PC-RPLND but no viable GCT; however, out of the four patients with mature teratoma, one had viable GCT and two had teratoma at PC-RPLND. Of the two patients with viable GCT, one had 100% embryonal cancer in the original pathology, prechemotherapeutic S2 tumor markers, history of orchiopexy, and no vascular invasion; the other patient had yolk sac tumor with 25% embryonal elements and 40% teratoma in the original pathology, and prechemotherapeutic S2 tumor markers. Conclusion: None of the clinical or pathological parameters showed a strong correlation with the presence of viable GCT in PC-RPLND. However, patients with ≥S2 may be at higher risk to have viable GCT. Further studies are needed to clarify this.

RF gun using laser-triggered photocathode

International Nuclear Information System (INIS)

Akiyama, H.; Otake, Y.; Naito, T.; Takeuchi, Y.; Yoshioka, M.

1992-01-01

An RF gun using laser-triggered photocathode has many advantages as an injector of the linear colliders since it can generate a low emittance and high current pulsed beam. The experimental facility for the RF gun, such as an RF system, a laser system and a photocathode have been fabricated to study the fundamental characteristics. The dynamics of the RF gun has also studied by the 1D sheet beam model. (author)

Predicting retroperitoneal histology in postchemotherapy testicular germ cell cancer : A model update and multicentre validation with more than 1000 patients

NARCIS (Netherlands)

Vergouwe, Yvonne; Steyerberg, Ewout W.; Foster, Richard S.; Sleijfer, Dirk T.; Fossa, Sophie D.; Gerl, Arthur; de Wit, Ronald; Roberts, J. Trevor; Habbema, J. Dik F.

Objectives: Surgical resection of postchemotherapy retroperitoneal lymph nodes is often performed in patients with advanced nonseminomatous testicular germ cell cancer. We previously developed a model to predict the probability that the lymph nodes contain only necrotic or fibrotic (benign) tissue

BRS 369RF and BRS 370RF: Glyphosate tolerant, high-yielding upland cotton cultivars for central Brazilian savanna

Directory of Open Access Journals (Sweden)

Camilo de Lelis Morello

2015-12-01

Full Text Available BRS 369RF and BRS 370RF were developed by the EMBRAPA as a part of efforts to create high-yielding germplasm with combinations of transgenic traits. BRS 369RF and BRS 370RF are midseason cultivars and have yield stability, adaptation to the central Brazilian savanna, good fiber quality and tolerance to glyphosate herbicide.

RF and microwave microelectronics packaging II

CERN Document Server

Sturdivant, Rick

2017-01-01

Reviews RF, microwave, and microelectronics assembly process, quality control, and failure analysis Bridges the gap between low cost commercial and hi-res RF/Microwave packaging technologies Engages in an in-depth discussion of challenges in packaging and assembly of advanced high-power amplifiers This book presents the latest developments in packaging for high-frequency electronics. It is a companion volume to “RF and Microwave Microelectronics Packaging” (2010) and covers the latest developments in thermal management, electrical/RF/thermal-mechanical designs and simulations, packaging and processing methods, and other RF and microwave packaging topics. Chapters provide detailed coverage of phased arrays, T/R modules, 3D transitions, high thermal conductivity materials, carbon nanotubes and graphene advanced materials, and chip size packaging for RF MEMS. It appeals to practicing engineers in the electronic packaging and high-frequency electronics domain, and to academic researchers interested in underst...

Low frequency rf current drive

International Nuclear Information System (INIS)

Hershkowitz, N.

1992-01-01

An unshielded antenna for rf heating has been developed and tested during this report period. In addition to design specifications being given, some experimental results are presented utilizing: (1) an unprotected Faraday shield, (2) insulating guard limiters, (3) unshielded antenna experiments, (4) method for detecting small rf driven currents, (5) rf fast wave current drive experiments, (6) alfven wave interactions with electrons, and (7) machine conditioning, impurity generation and density control

Retroperitoneal relapse of non-seminomatous testicular cancer: computed tomography findings before retroperitoneal lymphadenectomy; Retroperitoneale Rezidive nicht-seminomatoeser Hodentumoren: Computertomographische Befunde vor retroperitonealer Lymphadenektomie

Energy Technology Data Exchange (ETDEWEB)

Hosten, N.; Stroszczynski, C.; Lemke, M.; Felix, R. [Strahlenklinik und Poliklinik, Charite Campus Virchow, Humboldt Univ. zu Berlin (Germany); Rick, O. [Abt. Innere Medizin mit Schwerpunkt Haematologie/Onkologie, Charite Campus Virchow, Humboldt Univ. zu Berlin (Germany)

1999-01-01

Purpose: In relapsing testicular cancer, additional chemotherapy is followed by abdominal CT. If residual lesions are found, retroperitoneal lymphadenectomy is considered. We studied retrospectively whether morphological criteria can help in selected cases in deciding about lymphadenectomy by distinguishing between vital tumor, scarring and mature teratoma. Methods: In 26 patients who had been treated by salvage chemotherapy and retroperitoneal lymphadenectomy for non-seminomatous testicular cancer between 1990 and 1997, abdominal computed tomography and histology were correlated. Results: Histological examination found scarring in 10 patients, vital tumor in 6, mature teratoma in 4, and simultaneous teratoma and vital tumor in 6. A single CT criterion for distinguishing between these histologies was not identified. In two patients with large masses which were partly cystic and partly solid vital tumor and teratoma were verified. Scarrings may be expected in cystic lesions at the level of the renal hilus which are lined by a thin and smooth wall. Size did not matter. Conclusion: Accurate differentiation between vital tumor and necrosis was not possible. Before lymphadenectomy CT, however, localised lesions. (orig.) [Deutsch] Ziel: Bei Patienten mit rezidivierten Hodentumoren wird nach erneuter Chemotherapie die abdominelle CT durchgefuehrt. Wenn verbliebene Raumforderungen nachgewiesen werden, wird eine retroperitoneale Lymphadenektomie in Betracht gezogen. Untersucht wurde, ob der Bildbefund Hinweise auf das Vorliegen von vitalem Tumor, Nekrose bzw. Narbe oder reifem Teratom geben kann, die in Einzelfaellen zur Indikationsstellung herangezogen werden koennten. Methoden: Bei 26 Patienten, die wegen eines rezidivierten nicht-seminomatoesen Hodentumors in den Jahren 1990 bis 1997 einer erneuten Chemotherapie mit anschliessender retroperitonealer Lymphadenektomie von Tumorresten unterzogen worden waren, wurden abdominelle CT und Histologie korreliert. Ergebnisse: Die

RF measurements I: signal receiving techniques

CERN Document Server

Caspers, F

2011-01-01

For the characterization of components, systems and signals in the RF and microwave range, several dedicated instruments are in use. In this paper the fundamentals of the RF-signal sampling technique, which has found widespread applications in 'digital' oscilloscopes and sampling scopes, are discussed. The key element in these front-ends is the Schottky diode which can be used either as an RF mixer or as a single sampler. The spectrum analyser has become an absolutely indispensable tool for RF signal analysis. Here the front-end is the RF mixer as the RF section of modern spectrum analysers has a rather complex architecture. The reasons for this complexity and certain working principles as well as limitations are discussed. In addition, an overview of the development of scalar and vector signal analysers is given. For the determination of the noise temperature of a one-port and the noise figure of a two-port, basic concepts and relations are shown. A brief discussion of commonly used noise measurement techniq...

Technology development of solid state rf systems at 350 MHz and 325 MHz for RF accelerator

International Nuclear Information System (INIS)

Rama Rao, B.V.; Mishra, J.K.; Pande, Manjiri; Gupta, S.K.

2011-01-01

For decades vacuum tubes and klystrons have been used in high power application such as RF accelerators and broadcast transmitters. However, now, the solid-state technology can give power output in kilowatt regime. Higher RF power output can be achieved by combining several solid-state power amplifier modules using power combiners. This technology presents several advantages over traditional RF amplifiers, such as simpler start-up procedure, high modularity, high redundancy and flexibility, elimination of high voltage supplies and high power circulators, low operational cost, online maintenance without shut down of RF power station and no warm up time. In BARC, solid state amplifier technology development is being done both at 350 MHz and 325 MHz using RF transistors such as 1 kW LDMOS and 350 Watt VDMOS. Topology of input and output matching network in RF modules developed, consist of two L type matching sections with each section having a combination of series micro-strip line and parallel capacitor. The design is of equal Q for both the sections and of 25 ohm characteristics impedance of micro strip lines. Based on this, lengths of micro strips lines and values of shunt capacitors have been calculated. The calculated and simulated values of network elements have been compared. Similarly power combiners have been designed and developed based on Wilkinson techniques without internal resistors and using coaxial technology. This paper presents design and development of RF power amplifier modules, associated power combiner technologies and then integrated RF power amplifier. (author)

Liquid Metal Droplet and Micro Corrugated Diaphragm RF-MEMS for reconfigurable RF filters

Science.gov (United States)

Irshad, Wasim

Widely Tunable RF Filters that are small, cost-effective and offer ultra low power consumption are extremely desirable. Indeed, such filters would allow drastic simplification of RF front-ends in countless applications from cell phones to satellites in space by replacing switched-array of static acoustic filters and YIG filters respectively. Switched array of acoustic filters are de facto means of channel selection in mobile applications such as cell phones. SAW and BAW filters satisfy most criteria needed by mobile applications such as low cost, size and power consumption. However, the trade-off is a significant loss of 3-4 dB in modern cell phone RF front-end. This leads to need for power-hungry amplifiers and short battery life. It is a necessary trade-off since there are no better alternatives. These devices are in mm scale and consume mW. YIG filters dominate applications where size or power is not a constraint but demand excellent RF performance like low loss and high tuning ratio. These devices are measured in inches and require several watts to operate. Clearly, a tunable RF filter technology that would combine the cost, size and power consumption benefits of acoustic filters with excellent RF performance of YIG filters would be extremely desirable and imminently useful. The objective of this dissertation is to develop such a technology based upon RF-MEMS Evanescent-mode cavity filter. Two highly novel RF-MEMS devices have been developed over the course of this PhD to address the unique MEMS needs of this technology. The first part of the dissertation is dedicated to introducing the fundamental concepts of tunable cavity resonators and filters. This includes the physics behind it, key performance metrics and what they depend on and requirements of the MEMS tuners. Initial gap control and MEMS attachment method are identified as potential hurdles towards achieving very high RF performance. Simple and elegant solutions to both these issues are discussed in

Linear collider RF: Introduction and summary

International Nuclear Information System (INIS)

Palmer, R.B.

1995-01-01

The relation of acceleration gradient with RF frequency is examined, and approximate general RF power requirements are derived. Considerations of efficiency and cost are discussed. RF Sources, presented at the conference, are reviewed. Overall efficiencies of the linear collider proposals are compared. copyright 1995 American Institute of Physics

Content of the canceroembryonal antigen in tumours of the organs of the abdominal cavity and the retroperitoneal space

Energy Technology Data Exchange (ETDEWEB)

Tkacheva, G A; Klimenkov, A A; Gladikov, Yu V; Gabuniya, R I [Akademiya Meditsinskikh Nauk SSSR, Moscow. Onkologicheskij Nauchnyj Tsentr

1979-08-01

The concentration of the canceroembryonal antigen (CEA) has been determined in vitro by the radioimmunological analysis of the blood plasma of 70 donors and 130 patients with malignant tumours of the intestine (6 persons), stomach (77), with relapsing gastric carcinoma (12), tumours of the pancreas (7), retroperitoneal space (18) and with inflammatory disease of the gastrointestinal tract (12). It is established that the radioimmunological test in vitro for CEA can be used not only for primary diagnosis of cancer of the rectum but also as a substantial supplement to the clinical diagnosis of carcinoma of the stomach and the pancreas. A relationship revealed between the rise in the content of CEA and the extent of malignancy provides additional information for correct diagnosing the stage of gastric carcinoma and a choice of an adequate method of treatment. Tolerance of the CEA level in the blood in retroperitoneal tumours and inflammatory diseases of the gastrointestinal tract may serve as a criterion for differential diagnosis of malignant newgrowths in the abdominal cavity.

RF and feedback systems

International Nuclear Information System (INIS)

Boussard, D.

1994-01-01

The radiofrequency system of the Tau Charm Factory accelerating 10 11 particles per bunch and a circulating current of 0.5 A is presented. In order to produce the very short bunches required, the RF system of TCF must provide a large RF voltage (8 MV) at a frequency in the neighbourhood of 400-500 MHz. It appears very attractive to produce the high voltage required with superconducting cavities, for which wall losses are negligible. A comparison between the sc RF system proposed and a possible copper system run at an average 1 MV/m, shows the clear advantage of sc cavities for TCF. (R.P.). 2 figs,. 1 tab

Compined preoperative diagnosis of stomach cancer involvement of the abdominal and retroperitoneal organs and tissues

International Nuclear Information System (INIS)

Fisher, M.E.; Gabuniya, R.I.; Kolesnikova, E.K.; Bal'ter, S.A.; Ostrovtsev, I.V.; Dolgushin, B.I.; Mazurov, S.T.; Mironova, G.T.

1987-01-01

An analysis of 136 cases of stomach cancer led to the determination of the role and place of gammatopography, echography, computerized X-ray tomography, angiography and laparoscopy in specified preoperative diagnosis of extraorganic spreading of primary tumors. The informative value and shortcomings of certain methods were shown. A high accuracy of the entire set of diagnostic procedures (94.8%) in the preoperative definition of stomach cancer involvement of the abdominal and retroperitoneal organs and tissues was emphasized

Stochastic cooling with a double rf system

International Nuclear Information System (INIS)

Wei, Jie.

1992-01-01

Stochastic cooling for a bunched beam of hadrons stored in an accelerator with a double rf system of two different frequencies has been investigated. The double rf system broadens the spread in synchrotron-oscillation frequency of the particles when they mostly oscillate near the center of the rf bucket. Compared with the ease of a single rf system, the reduction rates of the bunch dimensions are significantly increased. When the rf voltage is raised, the reduction rate, instead of decreasing linearly, now is independent of the ratio of the bunch area to the bucket area. On the other hand, the spread in synchrotron-oscillation frequency becomes small with the double rf system, if the longitudinal oscillation amplitudes of the particles are comparable to the dimension of the rf bucket. Consequently, stochastic cooling is less effective when the bunch area is close to the bucket area

RF Group Annual Report 2011

CERN Document Server

Angoletta, M E; Betz, M; Brunner, O; Baudrenghien, P; Calaga, R; Caspers, F; Ciapala, E; Chambrillon, J; Damerau, H; Doebert, S; Federmann, S; Findlay, A; Gerigk, F; Hancock, S; Höfle, W; Jensen, E; Junginger, T; Liao, K; McMonagle, G; Montesinos, E; Mastoridis, T; Paoluzzi, M; Riddone, G; Rossi, C; Schirm, K; Schwerg, N; Shaposhnikova, E; Syratchev, I; Valuch, D; Venturini Delsolaro, W; Völlinger, C; Vretenar, M; Wuensch, W

2012-01-01

The highest priority for the RF group in 2011 was to contribute to a successful physics run of the LHC. This comprises operation of the superconducting 400 MHz accelerating system (ACS) and the transverse damper (ADT) of the LHC itself, but also all the individual links of the injector chain upstream of the LHC – Linac2, the PSB, the PS and the SPS – don’t forget that it is RF in all these accelerators that truly accelerates! A large variety of RF systems had to operate reliably, often near their limit. New tricks had to be found and implemented to go beyond limits; not to forget the equally demanding operation with Pb ions using in addition Linac3 and LEIR. But also other physics users required the full attention of the RF group: CNGS required in 2011 beams with very short, intense bunches, AD required reliable deceleration and cooling of anti-protons, Isolde the post-acceleration of radioactive isotopes in Rex, just to name a few. In addition to the supply of beams for physics, the RF group has a num...

Rf power sources

International Nuclear Information System (INIS)

Allen, M.A.

1988-05-01

This paper covers RF power sources for accelerator applications. The approach has been with particular customers in mind. These customers are high energy physicists who use accelerators as experimental tools in the study of the nucleus of the atom, and synchrotron light sources derived from electron or positron storage rings. This paper is confined to electron-positron linear accelerators since the RF sources have always defined what is possible to achieve with these accelerators. 11 refs., 13 figs

Design and development of RF system for vertical test stand for characterization of superconducting RF cavities

International Nuclear Information System (INIS)

Mohania, Praveen; Rajput, Vikas; Baxy, Deodatta; Agrawal, Ankur; Mahawar, Ashish; Adarsh, Kunver; Singh, Pratap; Shrivastava, Purushottam

2011-01-01

RRCAT is developing a Vertical Test Stand (VTS) to test and qualify 1.3 GHz/650 MHz, SCRF Cavities in collaboration with Fermi National Accelerator Laboratory (FNAL) under Indian Institutions' Fermilab Collaboration. The technical details for VTS is being provided by FNAL, USA. The RF System of VTS needs to provide stable RF power to SCRF cavity with control of amplitude, relative phase and frequency. The incident, reflected, transmitted power and field decay time constant of the cavity are measured to evaluate cavity performance parameters (E, Qo). RF Power is supplied via 500 W Solid State amplifier, 1270-1310 MHz being developed by PHPMS, RRCAT. VTS system is controlled by PXI Platform and National Instruments LabVIEW software. Low Level RF (LLRF) system is used to track the cavity frequency using Phase Locked Loop (PLL). The system is comprised of several integrated functional modules which would be assembled, optimized, and tested separately. Required components and instruments have been identified and procurement for the same is underway. Inhouse development for the Solid State RF amplifier and instrument interfacing is in progress. This paper describes the progress on the development of the RF system for VTS. (author)

Low reflectance high power RF load

Science.gov (United States)

Ives, R. Lawrence; Mizuhara, Yosuke M.

2016-02-02

A load for traveling microwave energy has an absorptive volume defined by cylindrical body enclosed by a first end cap and a second end cap. The first end cap has an aperture for the passage of an input waveguide with a rotating part that is coupled to a reflective mirror. The inner surfaces of the absorptive volume consist of a resistive material or are coated with a coating which absorbs a fraction of incident RF energy, and the remainder of the RF energy reflects. The angle of the reflector and end caps is selected such that reflected RF energy dissipates an increasing percentage of the remaining RF energy at each reflection, and the reflected RF energy which returns to the rotating mirror is directed to the back surface of the rotating reflector, and is not coupled to the input waveguide. Additionally, the reflector may have a surface which generates a more uniform power distribution function axially and laterally, to increase the power handling capability of the RF load. The input waveguide may be corrugated for HE11 mode input energy.

Anatomy of the retroperitoneal space as shown by magnetic resonance imaging

International Nuclear Information System (INIS)

Zilch, H.G.; Hammersen, F.

1989-01-01

More than 300 NMR examinations form the basis of the survey presented of the anatomy and topography of the retroperitoneal space. The examinations were done with the Siemens supraconducting magnet system 'Magnetom' (1.0 Tesla), with different planes of imaging chosen, according to clinical approaches (axial, sagittal, frontal). Sectional thicknesses varied between 5 and 10 mm. The spin-echo technique was applied, with repetition times between 0.3 and 2.0s, echo times between 30 and 150 ms. In addition, special means such as high-resolution coils and respiratory gating were applied, and also a contrast medium (gadolinium-DTPA). The possibilities of imaging are explained, referring to the pancreas, kidneys, adrenal glands, lymph nodes, aorta abdominalis, and vena cava inferior. (orig./MG) [de

Review of pulsed rf power generation

International Nuclear Information System (INIS)

Lavine, T.L.

1992-04-01

I am going to talk about pulsed high-power rf generation for normal-conducting electron and positron linacs suitable for applications to high-energy physics in the Next Linear Collider, or NLC. The talk will cover some basic rf system design issues, klystrons and other microwave power sources, rf pulse-compression devices, and test facilities for system-integration studies

PEP-II RF System Operation and Performance

International Nuclear Information System (INIS)

McIntosh, P.

2005-01-01

The Low Energy Ring (LER) and High Energy Ring (HER) RF systems have operated now on PEP-II since July 1998 and have assisted in breaking all design luminosity records back in June 2001. Luminosity on PEP-II has steadily increased since then as a consequence of larger e+ and e- beam currents being accumulated. This has meant that the RF systems have inevitably been driven harder, not only to achieve these higher stored beam currents, but also to reliably keep the beams circulating whilst at the same time minimizing the number of aborts due to RF system faults. This paper details the current PEP-II RF system configurations for both rings, as well as future upgrade plans spanning the next 3-5 years. Limitations of the current RF system configurations are presented, highlighting improvement projects which will target specific areas within the RF systems to ensure that adequate operating overheads are maintained and reliable operation is assured. The Low Energy Ring (LER) and High Energy Ring (HER) RF systems have operated now on PEP-II since July 1998 and have assisted in breaking all design luminosity records back in June 2001. Luminosity on PEP-II has steadily increased since then as a consequence of larger e+ and e- beam currents being accumulated. This has meant that the RF systems have inevitably been driven harder, not only to achieve these higher stored beam currents, but also to reliably keep the beams circulating whilst at the same time minimizing the number of aborts due to RF system faults. This paper details the current PEP-II RF system configurations for both rings, as well as future upgrade plans spanning the next 3-5 years. Limitations of the current RF system configurations are presented, highlighting improvement projects which will target specific areas within the RF systems to ensure that adequate operating overheads are maintained and reliable operation is assured

RF-Station control crate

International Nuclear Information System (INIS)

Beuzekom, M.G. van; Es, J.T. van.

1992-01-01

This report gives a description of the electronic control-system for the RF-station of AmPS. The electronics form the connection between the computer-system and the hardware of the RF-station. Only the elements of the systems which are not described in the other NIKHEF-reports are here discussed in detail. (author). 7 figs

RF front-end world class designs

CERN Document Server

Love, Janine

2009-01-01

All the design and development inspiration and direction a harware engineer needs in one blockbuster book! Janine Love site editor for RF Design Line,columnist, and author has selected the very best RF design material from the Newnes portfolio and has compiled it into this volume. The result is a book covering the gamut of RF front end design from antenna and filter design fundamentals to optimized layout techniques with a strong pragmatic emphasis. In addition to specific design techniques and practices, this book also discusses various approaches to solving RF front end design problems and h

Mentored retroperitoneal laparoscopic renal surgery in children: a safe approach to learning.

Science.gov (United States)

Farhat, W; Khoury, A; Bagli, D; McLorie, G; El-Ghoneimi, A

2003-10-01

To review the feasibility of introducing advanced retroperitoneal renal laparoscopic surgery (RRLS) to a paediatric urology division, using the mentorship-training model. Although the scope of practice in paediatric urology is currently adapting endoscopic surgery into daily practice, most paediatric urologists in North America have had no formal training in laparoscopic surgery. The study included four paediatric urologists with 3-25 years of practice; none had had any formal laparoscopic training or ever undertaken advanced RRLS. An experienced laparoscopic surgeon (the mentor) assisted the learning surgeons over a year. The initial phases of learning incorporated detailed lectures, visualization through videotapes and 'hands-on' demonstration by the expert in the technique of the standardized steps for each type of surgery. Over 10 months, ablative and reconstructive RRLS was undertaken jointly by the surgeons and the mentor. After this training the surgeons operated independently. To prevent lengthy operations, conversion to open surgery was planned if there was no significant progression after 2 h of laparoscopic surgery. Over the 10 months of mentorship, 36 RRLS procedures were undertaken in 31 patients (28 ablative and eight reconstructive). In all cases the mentored surgeons accomplished both retroperitoneal access and the creation of a working space within the cavity. The group was able to initiate ablative RRLS but the mentor undertook all the reconstructive procedures. After the mentorship period, over 10 months, 12 ablative procedures were undertaken independently, and five other attempts at RRLS failed. Although the mentored approach can successfully and safely initiate advanced RRLS in a paediatric urology division, assessing the laparoscopic practice pattern after mentorship in the same group of trainees is warranted. Ablative RRLS is easier to learn for the experienced surgeon, but reconstructive procedures, e.g. pyeloplasty, require a high degree

Investigation of MIM Diodes for RF Applications

KAUST Repository

Khan, Adnan

2015-01-01

zero bias condition as well as the possibility of realizing them through printing makes them attractive for (Radio Frequency) RF applications. However, MIM diodes have not been explored much for RF applications. One reason preventing their widespread RF

RF sheaths for arbitrary B field angles

Science.gov (United States)

D'Ippolito, Daniel; Myra, James

2014-10-01

RF sheaths occur in tokamaks when ICRF waves encounter conducting boundaries and accelerate electrons out of the plasma. Sheath effects reduce the efficiency of ICRF heating, cause RF-specific impurity influxes from the edge plasma, and increase the plasma-facing component damage. The rf sheath potential is sensitive to the angle between the B field and the wall, the ion mobility and the ion magnetization. Here, we obtain a numerical solution of the non-neutral rf sheath and magnetic pre-sheath equations (for arbitrary values of these parameters) and attempt to infer the parametric dependences of the Child-Langmuir law. This extends previous work on the magnetized, immobile ion regime. An important question is how the rf sheath voltage distributes itself between sheath and pre-sheath for various B field angles. This will show how generally previous estimates of the rf sheath voltage and capacitance were reasonable, and to improve the RF sheath BC. Work supported by US DOE grants DE-FC02-05ER54823 and DE-FG02-97ER54392.

Practical guide to RF-MEMS

CERN Document Server

Iannacci, Jacopo

2013-01-01

Closes the gap between hardcore-theoretical and purely experimental RF-MEMS books. The book covers, from a practical viewpoint, the most critical steps that have to be taken in order to develop novel RF-MEMS device concepts. Prototypical RF-MEMS devices, both including lumped components and complex networks, are presented at the beginning of the book as reference examples, and these are then discussed from different perspectives with regard to design, simulation, packaging, testing, and post-fabrication modeling. Theoretical concepts are introduced when necessary to complement the practical

Diagnostic Accuracy of Selective 3-T MR Neurography-guided Retroperitoneal Genitofemoral Nerve Blocks for the Diagnosis of Genitofemoral Neuralgia.

Science.gov (United States)

Fritz, Jan; Dellon, A Lee; Williams, Eric H; Rosson, Gedge D; Belzberg, Allan J; Eckhauser, Frederick E

2017-10-01

Purpose To determine if 3-T magnetic resonance (MR) neurography-guided retroperitoneal genitofemoral nerve (GFN) blocks are safe and effective for the diagnosis of genitofemoral neuralgia. Materials and Methods Following institutional review board approval and informed consent, 26 subjects (16 men, 10 women; mean age, 42 years [range, 24-78 years]; mean body mass index, 28 kg/m 2 [range, 20-35 kg/m 2 ]) with intractable groin pain were included. By using a 3-T MR imaging system, intermediate-weighted turbo spin-echo pulse sequences, and MR-conditional needles, diagnostic MR neurography-guided GFN blocks were performed in the retroperitoneum. Outcome variables included technical success, procedure time, complications, and rates of positive and negative GFN blocks in association with therapeutic outcomes. For the assessment of a learning curve, Mann-Whitney test was used. P values ≤ .05 were considered to indicate a statistically significant difference. Results In 26 subjects, 30 retroperitoneal GFN blocks were performed. Twelve (40%) were performed with an anterior needle path, 12 (40%) with a lateral needle path, and six (20%) with a posterior needle path. GFN blocks were technically successful in 24 of 26 (92%) subjects, achieving appropriate scrotal anesthesia. No complications occurred. The time required for a GFN block was 40 minutes (range, 18-67 minutes). The rate of a successful GFN intervention after a positive GFN block was 88% (14 of 16). The rate of a successful intervention of an alternative target after a negative GFN block was 71% (five of seven). Conclusion Selective retroperitoneally directed MR neurography-guided GFN blocks are safe and effective with high technical success and positive effect on surgical decision making in patients with presumed genitofemoral neuralgia. © RSNA, 2017 Online supplemental material is available for this article.

The CEBAF RF Separator System Upgrade

International Nuclear Information System (INIS)

Hovater, J.; Mark Augustine; Al Guerra; Richard Nelson; Robert Terrell; Mark Wissmann

2004-01-01

The CEBAF accelerator uses RF deflecting cavities operating at the third sub-harmonic (499 MHz) of the accelerating frequency (1497 MHz) to ''kick'' the electron beam to the experimental halls. The cavities operate in a TEM dipole mode incorporating mode enhancing rods to increase the cavity's transverse shunt impedance [1]. As the accelerators energy has increased from 4 GeV to 6 GeV the RF system, specifically the 1 kW solid-state amplifiers, have become problematic, operating in saturation because of the increased beam energy demands. Two years ago we began a study to look into replacement for the RF amplifiers and decided to use a commercial broadcast Inductive Output Tube (IOT) capable of 30 kW. The new RF system uses one IOT amplifier on multiple cavities as opposed to one amplifier per cavity as was originally used. In addition, the new RF system supports a proposed 12 GeV energy upgrade to CEBAF. We are currently halfway through the upgrade with three IOTs in operation and the remaining one nearly installed. This paper reports on the new RF system and the IOT performance

Superconducting RF activities at Cornell University

International Nuclear Information System (INIS)

Kirchgessner, J.; Moffat, D.; Padamsee, H.; Rubin, D.; Sears, J.; Shu, Q.S.

1990-01-01

This paper outlines the RF superconductivity research and development work that has taken place at Cornell Laboratory of Nuclear Studies over the past years. The work that has been performed since the last RF superconductivity workshop is emphasized together with a discussion of the direction of future efforts. Past work is summarized first, focusing on research and development activities in the area of RF superconductivity. Superconducting TeV linear collider is then discussed focusing on the application of superconducting RF to a future TeV linear collider. Linear collider structure development is then described centering on the development of a simpler (thereby cheaper) structure for a TeV linear collider. B-factory with superconducting RF is outlined focusing on the formulation of a conceptual design for a B-factory. B-factory structure development is discussed in relation to the advancement in the capability of SC cavities to carry beam currents of several amperes necessary for a high luminosity storage ring. High gradients are discussed as the key to the realization of a high energy superconducting linac or a superconducting RF B-factory. (N.K.)

Synchronization of RF fields of Indus 2 RF cavities for proper injection and acceleration of beam

International Nuclear Information System (INIS)

Tiwari, Nitesh; Bagduwal, Pritam S.; Lad, M.; Hannurkar, P.R.

2009-01-01

Indus-2 is a synchrotron light source with designed parameters of 2.5 GeV, 300 mA beam current. Four RF cavities fed from four RF power stations have been used for beam acceleration from 550 MeV to 2.5 GeV and synchrotron loss compensation. Particle should reach the RF cavity at the proper phase for proper acceptance of the beam in ring. At injection if the phase is not proper the acceptance efficiency reduces and the maximum stored current in the ring also gets limited. Equal contribution from four cavities at every value of current and energy level is very important. Improper phase will cause the imbalance of the power among different station hence will limit maximum stored current and reduce life time of the stored beam. Phase optimization was done in two-step, first at injection to have better injection rate and the stations were operated at the sufficient power for control loops to operate. Then at 2 GeV and 2.5 GeV energy so that beam extracts equal power from all four RF stations. Phase synchronization of all four cavities from injection to 2.5 GeV has already been done at 50 mA stored beam current. If phases of RF fields inside four RF cavities is not proper then beam will not see the total RF voltage as summation of all four cavity gap voltages, hence it is a very important parameter to be optimized and maintained during operation. (author)

Far-field RF energy transfer and harvesting

NARCIS (Netherlands)

Visser, H.J.; Vullers, R.; Briand, D.; Yeatman, E.; Roundy, S.

2015-01-01

This chapter deals with radio frequency (RF) energy transfer over a distance. After explaining the differences between nonradiative and radiative RF energy transfer, the chapter gives definitions for transfer and harvesting. Nonradiative RF energy transfer is mostly employed in inductive systems,

Desmoid-type fibromatosis: a front-line conservative approach to select patients for surgical treatment.

Science.gov (United States)

Fiore, Marco; Rimareix, Françoise; Mariani, Luigi; Domont, Julien; Collini, Paola; Le Péchoux, Cecile; Casali, Paolo G; Le Cesne, Axel; Gronchi, Alessandro; Bonvalot, Sylvie

2009-09-01

Surgery is still the standard treatment for desmoid-type fibromatosis (DF). Recently, the Institut Gustave Roussy (IGR), Villejuif, France, reported a series of patients treated with a front-line conservative approach (no surgery and no radiotherapy). The disease remained stable in more than half of patients. This study was designed to evaluate this approach on the natural history of the disease in a larger series of patients. A total of 142 patients presenting to the IGR or Istituto Nazionale Tumori (INT), Milan, Italy, were initially treated using a front-line deliberately conservative policy. Their progression-free survival (PFS) was observed and a multivariate analysis was performed for major clinical variables. Seventy-four patients presented with primary tumor, 68 with recurrence. Eighty-three patients received a "wait & see" policy (W&S), whereas 59 were initially offered medical therapy (MT), mainly hormonal therapy and chemotherapy. A family history of sporadic colorectal cancer was present in 8% of patients. The 5-year PFS was 49.9% for the W&S group and 58.6% for the medically treated patients (P = 0.3196). Similar results emerged for primary and recurrent DF. Multivariate analysis identified no clinical variables as independent predictors of PFS. In the event of progression, all patients were subsequently managed safely. A conservative policy could be a safe approach to primary and recurrent DF, which could avoid unnecessary morbidity from surgery and/or radiation therapy. Half of patients had medium-term stable disease after W&S or MT. A multidisciplinary, stepwise approach should be prospectively tested in DF.

A low-power RF system with accurate synchronization for a S-band RF-gun using a laser-triggered photocathode

International Nuclear Information System (INIS)

Otake, Y.; Naito, T.; Shintake, T.; Takata, K.; Takeuchi, Y.; Urakawa, J.; Yoshioka, M.; Akiyama, H.

1992-01-01

An S-band RF-gun using a laser-triggered photocathode and its low-power RF system have been constructed. The main elements of the low-power RF system comprise a 600-W amplifier, an amplitude modulator, a phase detector, a phase shifter and a frequency-divider module. Synchronization between the RF fields for acceleration and the mode-locked laser pulses for beam triggering are among the important points concerning the RF-gun. The frequency divider module which down-converts from 2856 MHz(RF) to 89.25 MHz(laser), and the electrical phase-shifter were specially developed for stable phase control. The phase jitter of the frequency divider should be less than 10 ps to satisfy our present requirements. The first experiments to trigger and accelerate beams with the above-mentioned system were carried out in January, 1992. (Author) 6 figs., 5 refs

Reliability impact of RF tube technology for the NPB

International Nuclear Information System (INIS)

Bueck, J.C.

1989-01-01

Two reliability options, redundancy and operating margin, are examined to determine their effect on power system configurations using RF tube technology (klystron and klystrode) powered Neutral Particle Beam weapons. Redundance is addressed by providing an additional identical RF tube to the tubes required to power an accelerator RF element (DTL section, RFQ, or CCL). RF elements do not share RF power with other RF elements. Operating margin provides increased reliability by sizing the RF tubes such that tube operating levels may be increased compensate for the loss of a tube. It is shown that power system mass is affected by the choice of reliability measures, that higher power tubes coupled with higher power RF elements may mitigate mass increases, and that redundancy appears preferable to operating margin as a method of improving RF system reliability

ISR RF cavities

CERN Multimedia

1983-01-01

In each ISR ring the radiofrequency cavities were installed in one 9 m long straight section. The RF system of the ISR had the main purpose to stack buckets of particles (most of the time protons)coming from the CPS and also to accelerate the stacked beam. The installed RF power per ring was 18 kW giving a peak accelerating voltage of 20 kV. The system had a very fine regulation feature allowing to lower the voltage down to 75 V in a smooth and well controlled fashion.

Ability of Rf5 and Rf6 to Restore Fertility of Chinsurah Boro II-type Cytoplasmic Male Sterile Oryza Sativa (ssp. Japonica) Lines.

Science.gov (United States)

Zhang, Honggen; Che, Jianlan; Ge, Yongshen; Pei, Yan; Zhang, Lijia; Liu, Qiaoquan; Gu, Minghong; Tang, Shuzhu

2017-12-01

Three-line Oryza sativa (ssp. japonica) hybrids have been developed mainly using Chinsurah Boro II (BT)-type cytoplasmic male sterility (CMS). The Rf1 gene restores the fertility of BT-type CMS lines, and is the only fertility restorer gene (Rf) that has been used to produce three-line japonica hybrids. Using more Rf genes to breed BT-type restorer lines may broaden the genetic diversity of the restorer lines, and represents a viable approach to improve the heterosis level of BT-type japonica hybrids. We identified two major Rf genes from '93-11' that are involved in restoring the fertility of BT-type CMS plants. These genes were identified from resequenced chromosome segment substitution lines derived from a cross between the japonica variety 'Nipponbare' and the indica variety '93-11'. Molecular mapping results revealed that these genes were Rf5 and Rf6, which are the Rf genes that restore fertility to Honglian-type CMS lines. The BT-type F 1 hybrids with either Rf5 or Rf6 exhibited normal seed setting rates, but F 1 plants carrying Rf6 showed more stable seed setting rates than those of plants carrying Rf5 under heat-stress conditions. Furthermore, the seed setting rates of F 1 hybrids carrying both Rf5 and Rf6 were more stable than that of F 1 plants carrying only one Rf gene. Rf6 is an important genetic resource for the breeding of BT-type japonica restorer lines. Our findings may be useful for breeders interested in developing BT-type japonica hybrids.

Idiopathic retroperitoneal fibrosis associated with Hashimoto's thyroiditis in a patient with a single functioning kidney

Directory of Open Access Journals (Sweden)

Byung Sun Kim

2013-12-01

Full Text Available Retroperitoneal fibrosis (RPF is a rare disease characterized by the presence of fibroinflammatory tissue around the abdominal aorta and ureteral entrapment in most cases. Idiopathic RPF is frequently reported in association with autoimmune diseases; however, there have been few reports of idiopathic RPF associated with Hashimoto's thyroiditis. Here, we report a case of idiopathic RPF with Hashimoto's thyroiditis in a patient with a single functioning kidney, which was successfully treated by corticosteroid therapy and transient intraureteral stent insertion with a double-J catheter.

RF current distribution and topology of RF sheath potentials in front of ICRF antennae

International Nuclear Information System (INIS)

Colas, L.; Heuraux, S.; Bremond, S.; Bosia, G.

2005-01-01

The 2D (radial/poloidal) spatial topology of RF-induced convective cells developing radially in front of ion cyclotron range of frequency (ICRF) antennae is investigated, in relation to the spatial distribution of RF currents over the metallic structure of the antenna. This is done via a Green's function, determined from the ICRF wave coupling equations, and well-suited to open field lines extending toroidally far away on both sides of the antenna. Using such formalism, combined with a full-wave calculation using the 3D antenna code ICANT (Pecoul S. et al 2000 Comput. Phys. Commun. 146 166-87), two classes of convective cells are analysed. The first one appears in front of phased arrays of straps, and depending on the strap phasing, its topology is interpreted using the poloidal profiles of either the RF current or the RF voltage of the strip line theory. The other class of convective cells is specific to antenna box corners and is evidenced for the first time. Based on such analysis, general design rules are worked out in order to reduce the RF-sheath potentials, which generalize those proposed in the earlier literature, and concrete antenna design options are tested numerically. The merits of aligning all strap centres on the same (tilted) flux tube, and of reducing the antenna box toroidal conductivity in its lower and upper parts, are discussed

A comparison of pelvic retroperitoneal pneumography and computed tomography in the assessment of extramural invasion of rectal carcinoma

International Nuclear Information System (INIS)

Kaibara, Nobuaki; Kimura, Osamu; Nishidoi, Hideaki; Ikeguchi, Masahide; Sugezawa, Akira; Sumi, Kenichi; Ohta, Michio; Koga, Shigemasa

1988-01-01

Pelvic retroperitoneal pneumography (PRP) and pelvic computed tomography (CT) were performed on 33 patients with rectal carcinoma in order to compare the usefulness of the two diagnostic procedures in the preoperative assessment of local malignant extramural invasion. Six PRP-negative patients in whom no free air was visualized in the retroperitoneal space surrounding the mass, were all assessed as having extramural invasion by CT scan and all had histologic evidence of invasion. Of 27 PRP-positive patients in whom free air was seen surrounding the mass, 18 were diagnosed as having extramural invasion on CT, 15 of whom had histologic proof of invasion. In the remaining 9 PRP-positive patients, there was no evidence of extramural invasion on the CT scans, but 5 patients showed evidence of invasion histologically. PRP, when positive, had an unacceptably high rate of being false positive and was therefore unreliable in assessing extramural invasion, whereas CT was able to detect, to some extent, extramural invasion which PRP failed to demonstrate. Based on these findings, we conclude that CT is more useful than PRP in the preoperative assessment of extramural invasion of rectal carcinoma, but is of limited diagnostic value when negative. (author)

Reducing Energy Degradation Due to Back-bombardment Effect with Modulated RF Input in S-band Thermionic RF Gun

Science.gov (United States)

Kii, Toshiteru; Nakai, Yoko; Fukui, Toshio; Zen, Heishun; Kusukame, Kohichi; Okawachi, Norihito; Nakano, Masatsugu; Masuda, Kai; Ohgaki, Hideaki; Yoshikawa, Kiyoshi; Yamazaki, Tetsuo

2007-01-01

Energy degradation due to back-bombardment effect is quite serious to produce high-brightness electron beam with long macro-pulse with thermionic rf gun. To avoid the back-bombardment problem, a laser photo cathode is used at many FEL facilities, but usually it costs high and not easy to operate. Thus we have studied long pulse operation of the rf gun with thermionic cathode, which is inexpensive and easy to operate compared to the photocathode rf gun. In this work, to reduce the energy degradation, we controlled input rf power amplitude by controlling pulse forming network of the power modulator for klystron. We have successfully increased the pulse duration up to 4 μs by increasing the rf power from 7.8 MW to 8.5 MW during the macro pulse.

SPEAR 2 RF SYSTEM LOADS

International Nuclear Information System (INIS)

2002-01-01

The design and performance of higher order mode (HOM) dampers for the SPEAR 2 RF system is presented. The SPEAR beam had experienced occasional periods of instability due to transverse oscillations which were driven by HOMs in the RF cavities. A substantial fraction of this RF energy was coupled out of the cavity into the waveguide connecting the cavity to the klystron. This waveguide was modified by adding a stub of smaller cross section, terminated by a ferrite tile load, to the system. Design considerations of the load, and its effect on HOMs and beam stability will be discussed

The FELIX RF system

International Nuclear Information System (INIS)

Manintveld, P.; Delmee, P.F.M.; Geer, C.A.J. van der; Meddens, B.J.H.; Meer, A.F.G. van der; Amersfoort, P.W. van

1992-01-01

The performance of the RF system for the Free Electron Laser for Infrared eXperiments (FELIX) is discussed. The RF system provides the input power for a triode gun (1 GHz, 100 W), a prebuncher (1 GHz, 10 kW), a buncher (3 GHz, 20 MW), and two linacs (3 GHz, 8 MW each). The pulse length in the system is 20 μs. The required electron beam stability imposes the following demands on the RF system: a phase stability better than 0.3 deg for the 1 GHz signals and better than 1 deg for the 3 GHz signals; the amplitude stability has to be better than 1% for the 1 GHz and better than 0.2% for the 3 GHz signals. (author) 3 refs.; 6 figs

Discussion of high brightness rf linear accelerators

International Nuclear Information System (INIS)

Jameson, R.A.

1987-01-01

The fundamental aspects of high-brightness rf linacs are outlined, showing the breadth and complexity of the technology and indicating that synergism with advancements in other areas is important. Areas of technology reviewed include ion sources, injectors, rf accelerator structures, beam dynamics, rf power, and automatic control

A rare case of retroperitoneal malignant triton tumor invading renal vein and small intestine

Directory of Open Access Journals (Sweden)

Mijović Žaklina

2013-01-01

Full Text Available Introduction. Malignant Triton tumor is a very rare malignant peripheral nerve sheath tumor with rhabdomyosarcomatous differentiation. Most of those tumors occur in patients with von Recklinghausen’s disease or as a late complication of irradiation and commonly seen in the head, neck, extremities and trunk. Case report. We reported retroperitoneal malignant Triton tumor in a 57-year-old female patient. Skin lesions were not present, and there was no family history of neurofibromatosis or previous irradiation. The presented case is one of a few recorded in the specialized literature that occurs in the retroperitoneal space in sporadic form. In this case, tumor consisted of a multilobular mass was in close relation with the abdominal aorta and inferior vena cava and involved the renal vein with gross invasion of the small intestine. The patient underwent total resection of the tumor and left nefrectomy was performed. The small intestine 10 cm in length was also resected and end-to-end anastomosis was conducted. The postoperative course was uneventful and the patient was discharged from the hospital ten days after the surgery. Conclusion. Diagnostically, it is crucial to recognize this uncommon histological variant because malignant Triton tumor has a worse prognosis than classic malignant peripheral nerve sheath tumor does. The use of the immunohistochemistry is essential in making the correct diagnosis. Only appropriate pathological evaluation supported by immunostaining with S-100 protein and desmin confirmed the diagnosis. Aggressive surgical management treatment improves the prognosis of such cases with adjuvant radiotherapy.

Pulsed rf excited spectrometer having improved pulse width control

International Nuclear Information System (INIS)

1977-01-01

RF excitation for a spectrometer is obtained by pulse width modulating an RF carrier to produce the desired broadband RF exciting spectrum. The RF excitation includes a train of composite RF pulses, each composite pulse having a primary pulse portion of a first RF phase and a second pulse portion of a second RF phase opposite that of the first. In this manner, the finite rise and fall times of the primary pulse portion are compensated for by the corresponding rise and fall times of the secondary pulse portion. The primary pulse portion is lengthened by an amount equal to the secondary pulse portion so that the secondary pulse portion cancels the added primary pulse portion. In a spectrometer, the compensating second pulse component removes certain undesired side bands of the RF excitation caused by the finite rise and fall times of the applied RF pulses. The compensating second pulse component removes certain undesired side bands associated with each of the resonant lines of the excited resonance spectrum of the sample under analysis, particularly for wide band RF excitation

Broadband direct RF digitization receivers

CERN Document Server

Jamin, Olivier

2014-01-01

This book discusses the trade-offs involved in designing direct RF digitization receivers for the radio frequency and digital signal processing domains.  A system-level framework is developed, quantifying the relevant impairments of the signal processing chain, through a comprehensive system-level analysis.  Special focus is given to noise analysis (thermal noise, quantization noise, saturation noise, signal-dependent noise), broadband non-linear distortion analysis, including the impact of the sampling strategy (low-pass, band-pass), analysis of time-interleaved ADC channel mismatches, sampling clock purity and digital channel selection. The system-level framework described is applied to the design of a cable multi-channel RF direct digitization receiver. An optimum RF signal conditioning, and some algorithms (automatic gain control loop, RF front-end amplitude equalization control loop) are used to relax the requirements of a 2.7GHz 11-bit ADC. A two-chip implementation is presented, using BiCMOS and 65nm...

Late effects of intraoperative radiation therapy on retroperitoneal tissues, intestine, and bile duct in a large animal model

International Nuclear Information System (INIS)

Sindelar, W.F.; Tepper, J.E.; Kinslla, T.J.; Barnes, M.; DeLuca, A.M.; Terrill, R.; Matthews, D.; Johnstone, P.A.S.; Anderson, W.J.; Bollinger, B.K.

1994-01-01

The late histopathological effects of intraoperative radiotherapy (IORT) on retroperitoneal tissues, intestine, and bile duct were investigated in dogs. Fourteen adult foxhounds were subjected to laparotomy and varying doses (0-45 Gy) of IORT (11 MeV electrons) delivered to retroperitoneal tissues including the great vessels and ureters, to a loop of defunctionalized small bowel, or to the extrahepatic bile duct. One control animal received an aortic transection and reanastomosis at the time of laparotomy; another control received laparotomy alone. This paper describes the late effects of single-fraction IORT occurring 3-5 years following treatment. Dogs receiving IORT to the retroperitoneum through a 4 X 15 cm portal showed few gross or histologic abnormalities at 20 Gy. At doses ranging from 30-45 Gy, radiation changes in normal tissues were consistently observed. Retroperitoneal fibrosis with encasement of the ureters and great vessels developed at doses ≥30 Gy. Radiation changes were present in the aorta and vena cava at doses ≥40 Gy. A 30 Gy dog developed an in-field malignant osteosarcoma at 3 years which invaded the vertebral column and compressed the spinal cord. A 40 Gy animal developed obstruction of the right ureter with fatal septic hydronephrosis at 4 years. Animals receiving IORT through a 5 cm IORT portal to an upper abdominal field which included a defunctionalized loop of small bowel, showed few gross or histologic abnormalities at a dose of 20 Gy. At 30 Gy, hyaline degeneration of the intestinal muscularis layer of the bowel occurred. At a dose of 45 Gy, internal intestinal fistulae developed. One 30 Gy animal developed right ureteral obstruction and hydronephrosis at 5 years. A dog receiving 30 Gy IORT through a 5 cm portal to the extrahepatic bile duct showed diffuse fibrosis through the gastroduodenal ligament. These canine studies contribute to the area of late tissue tolerance to IORT. 7 refs., 3 figs., 5 tabs

Late effects of intraoperative radiation therapy on retroperitoneal tissues, intestine, and bile duct in a large animal model

Energy Technology Data Exchange (ETDEWEB)

Sindelar, W.F.; Tepper, J.E.; Kinslla, T.J.; Barnes, M.; DeLuca, A.M.; Terrill, R.; Matthews, D.; Johnstone, P.A.S. [National Institutes of Health, Bethesda, MD (United States); Anderson, W.J. [Terre Haute Center for Medical Education, IN (United States); Bollinger, B.K. [National Naval Medical Center, Bethesda, MD (United States)

1994-07-01

The late histopathological effects of intraoperative radiotherapy (IORT) on retroperitoneal tissues, intestine, and bile duct were investigated in dogs. Fourteen adult foxhounds were subjected to laparotomy and varying doses (0-45 Gy) of IORT (11 MeV electrons) delivered to retroperitoneal tissues including the great vessels and ureters, to a loop of defunctionalized small bowel, or to the extrahepatic bile duct. One control animal received an aortic transection and reanastomosis at the time of laparotomy; another control received laparotomy alone. This paper describes the late effects of single-fraction IORT occurring 3-5 years following treatment. Dogs receiving IORT to the retroperitoneum through a 4 X 15 cm portal showed few gross or histologic abnormalities at 20 Gy. At doses ranging from 30-45 Gy, radiation changes in normal tissues were consistently observed. Retroperitoneal fibrosis with encasement of the ureters and great vessels developed at doses {ge}30 Gy. Radiation changes were present in the aorta and vena cava at doses {ge}40 Gy. A 30 Gy dog developed an in-field malignant osteosarcoma at 3 years which invaded the vertebral column and compressed the spinal cord. A 40 Gy animal developed obstruction of the right ureter with fatal septic hydronephrosis at 4 years. Animals receiving IORT through a 5 cm IORT portal to an upper abdominal field which included a defunctionalized loop of small bowel, showed few gross or histologic abnormalities at a dose of 20 Gy. At 30 Gy, hyaline degeneration of the intestinal muscularis layer of the bowel occurred. At a dose of 45 Gy, internal intestinal fistulae developed. One 30 Gy animal developed right ureteral obstruction and hydronephrosis at 5 years. A dog receiving 30 Gy IORT through a 5 cm portal to the extrahepatic bile duct showed diffuse fibrosis through the gastroduodenal ligament. These canine studies contribute to the area of late tissue tolerance to IORT. 7 refs., 3 figs., 5 tabs.

[Clinical spectrum of patients with spontaneous retroperitoneal hematomas].

Science.gov (United States)

Sánchez-González, Amada; Riancho-Zarrabeitia, Leyre; Salmón-González, Zaida; Riancho, José Antonio; Valero, Carmen

2015-10-05

Spontaneous retroperitoneal hematoma (SRH) is a potentially fatal clinical entity requiring immediate recognition and intervention. The clinical records of 18-year-old and older patients admitted to the University Hospital Marqués de Valdecilla from 2003 to 2013 were reviewed. "Spontaneous" was defined as unrelated to trauma, invasive procedures or bleeding due to aortic aneurysm rupture. Thirty-four patients with SRH (44% were on anticoagulant drugs). One-third of cases had chronic renal insufficiency. Abdominal pain was the most common symptom both in anticoagulated and non-anticoagulated patients (80% in anticoagulated and 89% in non-anticoagulated patients). About one half of the patients developed shock. A CT scan was the most commonly performed diagnostic test, followed by abdominal ultrasound. Most cases were managed conservatively (80%). More than half of the patients (66%) restarted anticoagulation therapy after the acute event with a mean delay of 19 days (range 2-90 days). None of them suffered a new bleeding episode. Restarting the anticoagulation treatment after hematoma resolution seems to be a safe practice. There is an increasing frequency of SRH in non-anticoagulated patients. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

Rf Station For Ion Beam Staking In Hirfl-csr

CERN Document Server

Arbuzov, V S; Bushuev, A A; Dranichnikov, A N; Gorniker, E I; Kendjebulatov, E K; Kondakov, A A; Kondaurov, M; Kruchkov, Ya G; Krutikhin, S A; Kurkin, G Ya; Mironenko, L A; Motygin, S V; Osipov, V N; Petrov, V M; Pilan, Andrey M; Popov, A M; Rashenko, V V; Selivanov, A N; Shteinke, A R; Vajenin, N F

2004-01-01

BINP has developed and produced the RF station for Institute of Modern Physics (IMP), Lanzhou, China, for multipurpose accelerator complex with electron cooling. The RF station will be used for accumulation of ion beams in the main ring of the system. It was successfully tested in IMP and installed into the main accelerator ring of the complex. The RF station includes accelerating RF cavity and RF power generator with power supplies. The station works within frequency range 6.0 - 14.0 MHz, maximum voltage across the accelerating gap of the RF cavity - 20 kV. In the RF cavity the 200 VNP ferrite is utilized. A residual gas pressure in vacuum chamber does not exceed 2,5E-11 mbar. Maximum output power of the RF generator 25 kW. The data acquisition and control of the RF station is based on COMPACT - PCI bus and provides all functions of monitoring and control.

New developments in RF power sources

International Nuclear Information System (INIS)

Miller, R.H.

1994-06-01

The most challenging rf source requirements for high-energy accelerators presently being studied or designed come from the various electron-positron linear collider studies. All of these studies except TESLA (the superconducting entry in the field) have specified rf sources with much higher peak powers than any existing tubes at comparable high frequencies. While circular machines do not, in general, require high peak power, the very high luminosity electron-positron rings presently being designed as B factories require prodigious total average rf power. In this age of energy conservation, this puts a high priority on high efficiency for the rf sources. Both modulating anodes and depressed collectors are being investigated in the quest for high efficiency at varying output powers

Multi-level RF identification system

Science.gov (United States)

Steele, Kerry D.; Anderson, Gordon A.; Gilbert, Ronald W.

2004-07-20

A radio frequency identification system having a radio frequency transceiver for generating a continuous wave RF interrogation signal that impinges upon an RF identification tag. An oscillation circuit in the RF identification tag modulates the interrogation signal with a subcarrier of a predetermined frequency and modulates the frequency-modulated signal back to the transmitting interrogator. The interrogator recovers and analyzes the subcarrier signal and determines its frequency. The interrogator generates an output indicative of the frequency of the subcarrier frequency, thereby identifying the responding RFID tag as one of a "class" of RFID tags configured to respond with a subcarrier signal of a predetermined frequency.

High power RF oscillator with Marx generators

International Nuclear Information System (INIS)

Murase, Hiroshi; Hayashi, Izumi

1980-01-01

A method to maintain RF oscillation by using many Marx generators was proposed and studied experimentally. Many charging circuits were connected to an oscillator circuit, and successive pulsed charging was made. This successive charging amplified and maintained the RF oscillation. The use of vacuum gaps and high power silicon diodes improved the characteristics of RF current cut-off of the circuit. The efficiency of the pulsed charging from Marx generators to a condenser was theoretically investigated. The theoretical result showed the maximum efficiency of 0.98. The practical efficiency obtained by using a proposed circuit with a high power oscillator was in the range 0.50 to 0.56. The obtained effective output power of the RF pulses was 11 MW. The maximum holding time of the RF pulses was about 21 microsecond. (Kato, T.)

Status of RF superconductivity at Argonne

International Nuclear Information System (INIS)

Shepard, K.W.

1990-01-01

Development of a superconducting slow-wave structures began at Argonne National Laboratory (ANL) in 1971, and led to the first superconducting heavy-ion linac (ATLAS - the Argonne Tandem-Linac Accelerator System). The Physics Division at ANL has continued to develop superconducting RF technology for accelerating heavy-ions, with the result that the linac has been in an almost continuous process of upgrade and expansion. In 1987, the Engineering Physics Division at ANL began developing of superconducting RF components for the acceleration of high-brightness proton and deuterium beams. The two divisions collaborate in work on several applications of RF superconductivity, and also in work to develop the technology generally. The present report briefly describes major features of the superconducting heavy-ion linac (very-low-velocity superconducting linac, positive ion injector), proton accelerating structures (superconducting resonant cavities for acceleration of high-current proton and deuteron beams, RF properties of oxide superconductors), and future work. Both divisions expect to continue a variety of studies, frequently in collaboration, to advance the basic technology of RF superconductivity. (N.K.)

Additive manufacturing of RF absorbers

Science.gov (United States)

Mills, Matthew S.

The ability of additive manufacturing techniques to fabricate integrated electromagnetic absorbers tuned for specific radio frequency bands within structural composites allows for unique combinations of mechanical and electromagnetic properties. These composites and films can be used for RF shielding of sensitive electromagnetic components through in-plane and out-of-plane RF absorption. Structural composites are a common building block of many commercial platforms. These platforms may be placed in situations in which there is a need for embedded RF absorbing properties along with structural properties. Instead of adding radar absorbing treatments to the external surface of existing structures, which adds increased size, weight and cost; it could prove to be advantageous to integrate the microwave absorbing properties directly into the composite during the fabrication process. In this thesis, a method based on additive manufacturing techniques of composites structures with prescribed electromagnetic loss, within the frequency range 1 to 26GHz, is presented. This method utilizes screen printing and nScrypt micro dispensing to pattern a carbon based ink onto low loss substrates. The materials chosen for this study will be presented, and the fabrication technique that these materials went through to create RF absorbing structures will be described. The calibration methods used, the modeling of the RF structures, and the applications in which this technology can be utilized will also be presented.

RF BREAKDOWN STUDIES USING PRESSURIZED CAVITIES

Energy Technology Data Exchange (ETDEWEB)

Johnson, Rolland

2014-09-21

Many present and future particle accelerators are limited by the maximum electric gradient and peak surface fields that can be realized in RF cavities. Despite considerable effort, a comprehensive theory of RF breakdown has not been achieved and mitigation techniques to improve practical maximum accelerating gradients have had only limited success. Part of the problem is that RF breakdown in an evacuated cavity involves a complex mixture of effects, which include the geometry, metallurgy, and surface preparation of the accelerating structures and the make-up and pressure of the residual gas in which plasmas form. Studies showed that high gradients can be achieved quickly in 805 MHz RF cavities pressurized with dense hydrogen gas, as needed for muon cooling channels, without the need for long conditioning times, even in the presence of strong external magnetic fields. This positive result was expected because the dense gas can practically eliminate dark currents and multipacting. In this project we used this high pressure technique to suppress effects of residual vacuum and geometry that are found in evacuated cavities in order to isolate and study the role of the metallic surfaces in RF cavity breakdown as a function of magnetic field, frequency, and surface preparation. One of the interesting and useful outcomes of this project was the unanticipated collaborations with LANL and Fermilab that led to new insights as to the operation of evacuated normal-conducting RF cavities in high external magnetic fields. Other accomplishments included: (1) RF breakdown experiments to test the effects of SF6 dopant in H2 and He gases with Sn, Al, and Cu electrodes were carried out in an 805 MHz cavity and compared to calculations and computer simulations. The heavy corrosion caused by the SF6 components led to the suggestion that a small admixture of oxygen, instead of SF6, to the hydrogen would allow the same advantages without the corrosion in a practical muon beam line. (2) A

A case of retroperitoneal carcinoid tumor which was radioeffective

International Nuclear Information System (INIS)

Nishimura, Kazuo; Ogawa, Osamu; Yoshimura, Naoki; Nakagawa, Takashi; Takahashi, Rei; Sasaki, Miharu.

1984-01-01

A 51-year-old man was referred to our hospital on May, 24, 1978, with complaints of lower abdominal pain, lower abdominal mass, constipation and pollakisuria. Physical examination revealed a lower abdominal tumor which was smooth, elastic soft and of childs' head size. IVP and urethrography revealed left nonvisualizing kidney, right hydronephrosis and deformity of bladder. CT scan revealed a large intrapelvic mass. Under the diagnosis of retroperitoneal tumor, operation was done on June, 29, 1978. Adhesive changes between the tumor, sacrococcyx and left internal iliac artery was so severe that the tumor could not be resected, and only biopsy-specimen was taken. Pathohistological diagnosis of the tumor was carcinoid tumor. He received postoperative radiation therapy with total dosis of 5000 rad in 5 weeks, and complete remission was obtained. Now, more than 5 years have passed after operation, no recurrence was detected. Carcinoid tumors are rare and generally are not radioeffective, but some cases without carcinoid syndrome, including our case, are radioeffective. So radiation therapy should be the second choice of treatment for carcinoid tumor. (author)

RF engineering basic concepts: S-parameters

CERN Document Server

Caspers, F

2011-01-01

The concept of describing RF circuits in terms of waves is discussed and the S-matrix and related matrices are defined. The signal flow graph (SFG) is introduced as a graphical means to visualize how waves propagate in an RF network. The properties of the most relevant passive RF devices (hybrids, couplers, non-reciprocal elements, etc.) are delineated and the corresponding S-parameters are given. For microwave integrated circuits (MICs) planar transmission lines such as the microstrip line have become very important.

The Development of the Electrically Controlled High Power RF Switch and Its Application to Active RF Pulse Compression Systems

Energy Technology Data Exchange (ETDEWEB)

Guo, Jiquan [Stanford Univ., CA (United States)

2008-12-01

In the past decades, there has been increasing interest in pulsed high power RF sources for building high-gradient high-energy particle accelerators. Passive RF pulse compression systems have been used in many applications to match the available RF sources to the loads requiring higher RF power but a shorter pulse. Theoretically, an active RF pulse compression system has the advantage of higher efficiency and compactness over the passive system. However, the key component for such a system an element capable of switching hundreds of megawatts of RF power in a short time compared to the compressed pulse width is still an open problem. In this dissertation, we present a switch module composed of an active window based on the bulk effects in semiconductor, a circular waveguide three-port network and a movable short plane, with the capability to adjust the S-parameters before and after switching. The RF properties of the switch module were analyzed. We give the scaling laws of the multiple-element switch systems, which allow the expansion of the system to a higher power level. We present a novel overmoded design for the circular waveguide three-port network and the associated circular-to-rectangular mode-converter. We also detail the design and synthesis process of this novel mode-converter. We demonstrate an electrically controlled ultra-fast high power X-band RF active window built with PIN diodes on high resistivity silicon. The window is capable of handling multi-megawatt RF power and can switch in 2-300ns with a 1000A current driver. A low power active pulse compression experiment was carried out with the switch module and a 375ns resonant delay line, obtaining 8 times compression gain with a compression ratio of 20.

Pulsed rf systems for large storage rings

International Nuclear Information System (INIS)

Wilson, P.B.

1979-03-01

The possibility is considered that by using a pulsed rf system a substantial reduction can be made in the rf power requirement for the next generation of large storage rings. For a ring with a sufficiently large circumference, the time between bunch passages, T/sub b/, can exceed the cavity filling time, T/sub f/. As the ratio T/sub b//T/sub f/ increases, it is clear that at some point the average power requirement can be reduced by pulsing the rf to the cavities. In this mode of operation, the rf power is turned on a filling time or so before the arrival of a bunch and is switched off again at the time of bunch passage. There is no rf energy in the accelerating structure, and hence no power dissipation, for most of the period between bunches

RF power generation for future linear colliders

International Nuclear Information System (INIS)

Fowkes, W.R.; Allen, M.A.; Callin, R.S.; Caryotakis, G.; Eppley, K.R.; Fant, K.S.; Farkas, Z.D.; Feinstein, J.; Ko, K.; Koontz, R.F.; Kroll, N.; Lavine, T.L.; Lee, T.G.; Miller, R.H.; Pearson, C.; Spalek, G.; Vlieks, A.E.; Wilson, P.B.

1990-06-01

The next linear collider will require 200 MW of rf power per meter of linac structure at relatively high frequency to produce an accelerating gradient of about 100 MV/m. The higher frequencies result in a higher breakdown threshold in the accelerating structure hence permit higher accelerating gradients per meter of linac. The lower frequencies have the advantage that high peak power rf sources can be realized. 11.42 GHz appears to be a good compromise and the effort at the Stanford Linear Accelerator Center (SLAC) is being concentrated on rf sources operating at this frequency. The filling time of the accelerating structure for each rf feed is expected to be about 80 ns. Under serious consideration at SLAC is a conventional klystron followed by a multistage rf pulse compression system, and the Crossed-Field Amplifier. These are discussed in this paper

Circuit design for RF transceivers

CERN Document Server

Leenaerts, Domine; Vaucher, Cicero S

2007-01-01

Second edition of this successful 2001 RF Circuit Design book, has been updated, latest technology reviews have been added as well as several actual case studies. Due to the authors being active in industry as well as academia, this should prove to be an essential guide on RF Transceiver Design for students and engineers.

RF Pulsed Heating

Energy Technology Data Exchange (ETDEWEB)

Pritzkau, David P.

2002-01-03

RF pulsed heating is a process by which a metal is heated from magnetic fields on its surface due to high-power pulsed RF. When the thermal stresses induced are larger than the elastic limit, microcracks and surface roughening will occur due to cyclic fatigue. Pulsed heating limits the maximum magnetic field on the surface and through it the maximum achievable accelerating gradient in a normal conducting accelerator structure. An experiment using circularly cylindrical cavities operating in the TE{sub 011} mode at a resonant frequency of 11.424 GHz is designed to study pulsed heating on OFE copper, a material commonly used in normal conducting accelerator structures. The high-power pulsed RF is supplied by an X-band klystron capable of outputting 50 MW, 1.5 {micro}s pulses. The test pieces of the cavity are designed to be removable to allow testing of different materials with different surface preparations. A diagnostic tool is developed to measure the temperature rise in the cavity utilizing the dynamic Q change of the resonant mode due to heating. The diagnostic consists of simultaneously exciting a TE{sub 012} mode to steady-state in the cavity at 18 GHz and measuring the change in reflected power as the cavity is heated from high-power pulsed RF. Two experimental runs were completed. One run was executed at a calculated temperature rise of 120 K for 56 x 10{sup 6} pulses. The second run was executed at a calculated temperature rise of 82 K for 86 x 10{sup 6} pulses. Scanning electron microscope pictures show extensive damage occurring in the region of maximum temperature rise on the surface of the test pieces.

Isolated Retroperitoneal Hydatid Cyst Invading Splenic Hilum

Directory of Open Access Journals (Sweden)

Safak Ozturk

2014-01-01

Full Text Available Introduction. Hydatid disease (HD is an infestation that is caused by the larval stage of Echinococcus granulosus. The liver is affected in approximately two-thirds of patients, the lungs in 25%, and other organs in a small proportion. Primary retroperitoneal hydatid cyst is extremely rare. The most common complaint is abdominal pain; however, the clinical features of HD may be generally dependent on the location of the cyst. Case Presentation. A 43-year-old female was admitted with the complaint of abdominal pain. Her physical examination was normal. Computed tomography (CT revealed a 17 × 11 cm cystic lesion, with a thick and smooth wall that is located among the left liver lobe, diaphragm, spleen, tail of the pancreas, and transverse colon and invading the splenic hilum. Total cystectomy and splenectomy were performed. Pathological examination was reported as cyst hydatid. Discussion. Cysts in the peritoneal cavity are mainly the result of the spontaneous or traumatic rupture of concomitant hepatic cysts or surgical inoculation of a hepatic cyst. Serological tests contribute to diagnosis. In symptomatic and large hydatid peritoneal cysts, surgical resection is the only curative treatment. Total cystectomy is the gold standard. Albendazole or praziquantel is indicated for inoperable and disseminated cases. Percutaneous aspiration, injection, and reaspiration (PAIR technique is another nonsurgical option.

The LHC Low Level RF

CERN Document Server

Baudrenghien, Philippe; Molendijk, John Cornelis; Olsen, Ragnar; Rohlev, Anton; Rossi, Vittorio; Stellfeld, Donat; Valuch, Daniel; Wehrle, Urs

2006-01-01

The LHC RF consists of eight 400 MHz superconducting cavities per ring, with each cavity independently powered by a 300 kW klystron, via a circulator. The challenge for the Low Level is to cope with very high beam current (more than 1 A RF component) and achieve excellent beam lifetime (emittance growth time in excess of 25 hours). Each cavity has an associated Cavity Controller rack consisting of two VME crates which implement high gain RF Feedback, a Tuner Loop with a new algorithm, a Klystron Ripple Loop and a Conditioning system. In addition each ring has a Beam Control system (four VME crates) which includes a Frequency Program, Phase Loop, Radial Loop and Synchronization Loop. A Longitudinal Damper (dipole and quadrupole mode) acting via the 400 MHz cavities is included to reduce emittance blow-up due to filamentation from phase and energy errors at injection. Finally an RF Synchronization system implements the bunch into bucket transfer from the SPS into each LHC ring. When fully installed in 2007, the...

Feasibility of retroperitoneal pelvic lymph node exploration in cervix-carcinoma treated by radio-surgery association or a definitive radiotherapy

International Nuclear Information System (INIS)

Bolla, M.; Sarrazin, R.; Berland, E.; Schmidt, M.H.; Rolachon, I.; Salvat, J.

1995-01-01

From June 1980 to May 1993, 52 patients with a mean age of 49, underwent a retroperitoneal pelvic lymph node laparoscopy procedure for cervix carcinoma classified as stage IA (14), IB (12), IIA (6), IIB (14), IIIB(3), IVA (3). Two techniques were used: a retroperitoneoscopy in 16 cases and a panoramic retroperitoneal pelviscopy (PRPP) in 36 cases. The aim was to define, with a better accuracy, the pelvic lymph node status, to adapt the target volume, and to estimate the morbidity.More nodes were biopsied with PRPP than with retroperitoneoscopy (p<0.05). There was a disagreement between the conventional radiologic assessment and the histological results in 28.6%. Specificity is 100%. Intra-operative and post-surgical morbidity was equivalent in the two procedures. One grade 3 urinary late morbidity (3%) was observed among the 33 patients who underwent a pelvic external irradiation. There was no morbidity of the gastro-intestinal tract. Discussion deals with the support offered by the two laparoscopic procedures to define the pelvic lymph node status, to choose the planning target volume, and to precise the lymph node boost. (authors) 24 refs., 3 tabs

Retroperitoneal Malignant Peripheral Nerve Sheath Tumor Replacing an Absent Kidney in a Child

Directory of Open Access Journals (Sweden)

Samin Alavi

2013-01-01

Full Text Available Malignant peripheral nerve sheath tumors (MPNSTs are nonrhabdomyosarcoma soft tissue sarcomas with rare occurrence in children specially in the retroperitoneum. We describe a young child who presented with an abdominal mass. Both ultrasound and computed tomography revealed a large right-sided abdominal mass in the anatomic place of right kidney, while no kidney or ureter was observed at that side. He underwent surgical resection of the tumor with a primary impression of Wilms tumor. To the authors’ knowledge, this is the first case of retroperitoneal malignant peripheral nerve sheath tumor and absent kidney. This case suggests the very rare probability of association of MPNSTs in children with genitourinary tract anomalies such as renal agenesis.

RF phase distribution systems at the SLC

International Nuclear Information System (INIS)

Jobe, R.K.; Schwarz, H.D.

1989-04-01

Modern large linear accelerators require RF distribution systems with minimal phase drifts and errors. Through the use of existing RF coaxial waveguides, and additional installation of phase reference cables and monitoring equipment, stable RF distribution for the SLC has been achieved. This paper discusses the design and performance of SLAC systems, and some design considerations for future colliders. 6 refs., 4 figs

RF properties of high-T/sub c/ superconductors

International Nuclear Information System (INIS)

Bohn, C.L.; Delayen, J.R.; Dos Santos, D.I.; Lanagan, M.T.; Shepard, K.W.

1988-01-01

We have investigated the rf properties of high-T/sub c/ superconductors over a wide range of temperature, frequency, and rf field amplitude. We have tested both bulk polycrystalline samples and thick films on silver substrates. At 150 MHz and 4.2 K, we have measured a surface resistance of 18 μ/sup /OMEGA// at low rf field and 3.6 m/sup /OMEGA// at an rf field of 270 gauss. All samples showed a strong dependence of the surface resistance on rf field; however, no breakdown of the superconducting state has been observed up to the highest field achieved (320 gauss). 9 refs., 4 figs., 1 tab

Comparability of scores on the MMPI-2-RF scales generated with the MMPI-2 and MMPI-2-RF booklets.

Science.gov (United States)

Van der Heijden, P T; Egger, J I M; Derksen, J J L

2010-05-01

In most validity studies on the recently released 338-item MMPI-2 (Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989) Restructured Form (MMPI-2-RF; Ben-Porath & Tellegen, 2008; Tellegen & Ben-Porath, 2008), scale scores were derived from the 567-item MMPI-2 booklet. In this study, we evaluated the comparability of the MMPI-2-RF scale scores derived from the original 567-item MMPI-2 booklet with MMPI-2-RF scale scores derived from the 338-item MMPI-2-RF booklet in a Dutch student sample (N = 107). We used a counterbalanced (ABBA) design. We compared results with those previously reported by Tellegen and Ben-Porath (2008). Our findings support the comparability of the scores of the 338-item version and the 567-item version of the 50 MMPI-2-RF scales. We discuss clinical implications and directions for further research.

Measurement of RF characteristics of magnetic alloys for an RF cavity of the accumulator cooler ring

International Nuclear Information System (INIS)

Watanabe, M.; Chiba, Y.; Katayama, T.; Koseki, T.; Ohtomo, K.; Tsutsui, H.

2004-01-01

The magnetic alloy (MA)-loaded RF cavity has been studied for an RF stacking system of the accumulator cooler ring (ACR). RF characteristics of several high-permeability MA cores were measured in the frequency range between 1 and 50 MHz. The effects of the cut-core configuration, cutting the core and leaving air gaps between two circular halves, were also investigated. The results show that the shunt impedance remains high and the appropriate inductance and Q-value can be obtained by increasing the gap width of the cut core in the frequency region of the ACR cavity

Study of Control Grid Thermionic Cathode RF Gun

CERN Document Server

Xiao, Jin; Ming, Li; Xinfan, Yang; Xumin, Shen; Yanan, Chen; Zhou, Xu

2004-01-01

In this paper, the beam loading effect of RF Gun was analyzed. To minimize the energy spread, the grid control RF Gun was introduced. The result shows that the grid congrol RF Gun can increase electron beam within 1% energy spread.

Development of L-band pillbox RF window

International Nuclear Information System (INIS)

Takeuchi, Y.; Fukuda, S.; Hisamatsu, H.; Saito, Y.; Takahashi, A.

1994-01-01

A pillbox RF output window was developed for the L-band pulsed klystron for the Japanese Hadron Project (JHP) 1-GeV proton linac. The window was designed to withstand a peak RF power of 6 MW, where the pulse width is 600 μsec and the repetition rate is 50 Hz. A high power model was fabricated using an alumina ceramic which has a low loss tangent of 2.5x10 -5 . A high power test was successfully performed up to a 113 kW RF average power with a 4 MW peak power, a 565 μsec pulse width and a 50 Hz repetition rate. By extrapolating the data of this high power test, the temperature rise of the ceramic is estimated low enough at the full RF power of 6 MW. Thus this RF window is expected to satisfy the specifications of the L-band Klystron. (author)

Microbunching and RF Compression

International Nuclear Information System (INIS)

Venturini, M.; Migliorati, M.; Ronsivalle, C.; Ferrario, M.; Vaccarezza, C.

2010-01-01

Velocity bunching (or RF compression) represents a promising technique complementary to magnetic compression to achieve the high peak current required in the linac drivers for FELs. Here we report on recent progress aimed at characterizing the RF compression from the point of view of the microbunching instability. We emphasize the development of a linear theory for the gain function of the instability and its validation against macroparticle simulations that represents a useful tool in the evaluation of the compression schemes for FEL sources.

Local Multi-Channel RF Surface Coil versus Body RF Coil Transmission for Cardiac Magnetic Resonance at 3 Tesla: Which Configuration Is Winning the Game?

Directory of Open Access Journals (Sweden)

Oliver Weinberger

Full Text Available The purpose of this study was to demonstrate the feasibility and efficiency of cardiac MR at 3 Tesla using local four-channel RF coil transmission and benchmark it against large volume body RF coil excitation.Electromagnetic field simulations are conducted to detail RF power deposition, transmission field uniformity and efficiency for local and body RF coil transmission. For both excitation regimes transmission field maps are acquired in a human torso phantom. For each transmission regime flip angle distributions and blood-myocardium contrast are examined in a volunteer study of 12 subjects. The feasibility of the local transceiver RF coil array for cardiac chamber quantification at 3 Tesla is demonstrated.Our simulations and experiments demonstrate that cardiac MR at 3 Tesla using four-channel surface RF coil transmission is competitive versus current clinical CMR practice of large volume body RF coil transmission. The efficiency advantage of the 4TX/4RX setup facilitates shorter repetition times governed by local SAR limits versus body RF coil transmission at whole-body SAR limit. No statistically significant difference was found for cardiac chamber quantification derived with body RF coil versus four-channel surface RF coil transmission. Our simulation also show that the body RF coil exceeds local SAR limits by a factor of ~2 when driven at maximum applicable input power to reach the whole-body SAR limit.Pursuing local surface RF coil arrays for transmission in cardiac MR is a conceptually appealing alternative to body RF coil transmission, especially for patients with implants.

Local Multi-Channel RF Surface Coil versus Body RF Coil Transmission for Cardiac Magnetic Resonance at 3 Tesla: Which Configuration Is Winning the Game?

Science.gov (United States)

Winter, Lukas; Dieringer, Matthias A.; Els, Antje; Oezerdem, Celal; Rieger, Jan; Kuehne, Andre; Cassara, Antonino M.; Pfeiffer, Harald; Wetterling, Friedrich; Niendorf, Thoralf

2016-01-01

Introduction The purpose of this study was to demonstrate the feasibility and efficiency of cardiac MR at 3 Tesla using local four-channel RF coil transmission and benchmark it against large volume body RF coil excitation. Methods Electromagnetic field simulations are conducted to detail RF power deposition, transmission field uniformity and efficiency for local and body RF coil transmission. For both excitation regimes transmission field maps are acquired in a human torso phantom. For each transmission regime flip angle distributions and blood-myocardium contrast are examined in a volunteer study of 12 subjects. The feasibility of the local transceiver RF coil array for cardiac chamber quantification at 3 Tesla is demonstrated. Results Our simulations and experiments demonstrate that cardiac MR at 3 Tesla using four-channel surface RF coil transmission is competitive versus current clinical CMR practice of large volume body RF coil transmission. The efficiency advantage of the 4TX/4RX setup facilitates shorter repetition times governed by local SAR limits versus body RF coil transmission at whole-body SAR limit. No statistically significant difference was found for cardiac chamber quantification derived with body RF coil versus four-channel surface RF coil transmission. Our simulation also show that the body RF coil exceeds local SAR limits by a factor of ~2 when driven at maximum applicable input power to reach the whole-body SAR limit. Conclusion Pursuing local surface RF coil arrays for transmission in cardiac MR is a conceptually appealing alternative to body RF coil transmission, especially for patients with implants. PMID:27598923

Local Multi-Channel RF Surface Coil versus Body RF Coil Transmission for Cardiac Magnetic Resonance at 3 Tesla: Which Configuration Is Winning the Game?

Science.gov (United States)

Weinberger, Oliver; Winter, Lukas; Dieringer, Matthias A; Els, Antje; Oezerdem, Celal; Rieger, Jan; Kuehne, Andre; Cassara, Antonino M; Pfeiffer, Harald; Wetterling, Friedrich; Niendorf, Thoralf

2016-01-01

The purpose of this study was to demonstrate the feasibility and efficiency of cardiac MR at 3 Tesla using local four-channel RF coil transmission and benchmark it against large volume body RF coil excitation. Electromagnetic field simulations are conducted to detail RF power deposition, transmission field uniformity and efficiency for local and body RF coil transmission. For both excitation regimes transmission field maps are acquired in a human torso phantom. For each transmission regime flip angle distributions and blood-myocardium contrast are examined in a volunteer study of 12 subjects. The feasibility of the local transceiver RF coil array for cardiac chamber quantification at 3 Tesla is demonstrated. Our simulations and experiments demonstrate that cardiac MR at 3 Tesla using four-channel surface RF coil transmission is competitive versus current clinical CMR practice of large volume body RF coil transmission. The efficiency advantage of the 4TX/4RX setup facilitates shorter repetition times governed by local SAR limits versus body RF coil transmission at whole-body SAR limit. No statistically significant difference was found for cardiac chamber quantification derived with body RF coil versus four-channel surface RF coil transmission. Our simulation also show that the body RF coil exceeds local SAR limits by a factor of ~2 when driven at maximum applicable input power to reach the whole-body SAR limit. Pursuing local surface RF coil arrays for transmission in cardiac MR is a conceptually appealing alternative to body RF coil transmission, especially for patients with implants.

Path-sum calculations for rf current drive

International Nuclear Information System (INIS)

Belo, Jorge H.; Bizarro, Joao P.S.; Rodrigues, Paulo

2001-01-01

Path sums and Gaussian short-time propagators are used to solve two-dimensional Fokker-Planck models of lower-hybrid (LH) and electron-cyclotron (EC) current drive (CD), and are shown to be well suited to the two limiting situations where the rf quasilinear diffusion coefficient is either relatively small, D rf ≅0.1, or very large, D rf →∞, the latter case enabling a special treatment. Results are given for both LHCD and ECCD in the small D rf case, whereas the limiting situation is illustrated only for ECCD. To check the accuracy of path-sum calculations, comparisons with finite difference solutions are provided

Geometry Optimization of DC/RF Photoelectron Gun

CERN Document Server

Chen Ping; Yu, David

2005-01-01

Pre-acceleration of photoelectrons in a pulsed, high voltage, short, dc gap and its subsequent injection into an rf gun is a promising method to improve electron beam emittance in rf accelerators. Simulation work has been performed in order to optimize the geometric shapes of a dc/rf gun and improve electron beam properties. Variations were made on cathode and anode shapes, dc gap distance, and inlet shape of the rf cavity. Simulations showed that significant improvement on the normalized emittance (< 1 mm-mrad), compared to a dc gun with flat cathode, could be obtained after the geometric shapes of the gun were optimized.

High power RF transmission line component development

International Nuclear Information System (INIS)

Hong, B. G.; Hwang, C. K.; Bae, Y. D.; Yoon, J. S.; Wang, S. J.; Gu, S. H.; Yang, J. R.; Hahm, Y. S.; Oh, G. S.; Lee, J. R.; Lee, W. I.; Park, S. H.; Kang, M. S.; Oh, S. H.; Lee, W.I.

1999-12-01

We developed the liquid stub and phase shifter which are the key high RF power transmission line components. They show reliable operation characteristics and increased insulation capability, and reduced the size by using liquid (silicon oil, dielectric constant ε=2.72) instead of gas for insulating dielectric material. They do not have finger stock for the electric contact so the local temperature rise due to irregular contact and RF breakdown due to scratch in conductor are prevented. They can be utilized in broadcasting, radar facility which require high RF power transmission. Moreover, they are key components in RF heating system for fusion reactor. (author)

High power RF transmission line component development

Energy Technology Data Exchange (ETDEWEB)

Hong, B. G.; Hwang, C. K.; Bae, Y. D.; Yoon, J. S.; Wang, S. J.; Gu, S. H.; Yang, J. R.; Hahm, Y. S.; Oh, G. S.; Lee, J. R.; Lee, W. I.; Park, S. H.; Kang, M. S.; Oh, S. H.; Lee, W.I

1999-12-01

We developed the liquid stub and phase shifter which are the key high RF power transmission line components. They show reliable operation characteristics and increased insulation capability, and reduced the size by using liquid (silicon oil, dielectric constant {epsilon}=2.72) instead of gas for insulating dielectric material. They do not have finger stock for the electric contact so the local temperature rise due to irregular contact and RF breakdown due to scratch in conductor are prevented. They can be utilized in broadcasting, radar facility which require high RF power transmission. Moreover, they are key components in RF heating system for fusion reactor. (author)

Idiopathic retroperitoneal fibrosis involving a unilateral renal sinus: A case report and literature review

International Nuclear Information System (INIS)

Lee, Seul Bi; Yoon, Jung Hee; Kim, Seung Ho; Lee, Ye Daum; Kim, Suk Jung; Lim, Yun Jung; Jung, Hyun Kyung; Lee, Jin Soo

2016-01-01

Idiopathic retroperitoneal fibrosis (RPF) is a rare disease entity and its etiology is uncertain. We report two similar cases which showed an uncommon presentation of idiopathic RPF. A 66-year-old woman and an 80-year-old man presented with incidental findings of left renal pelvic mass-like lesions. Computed tomography revealed a soft tissue density mass replacing the left renal pelvis, which was suspicious for renal pelvic cancer, and the diagnosis of idiopathic RPF was surgically confirmed. To the best of our knowledge, a few cases of idiopathic RPF presenting with features of a localized unilateral renal pelvic mass mimicking renal pelvic cancer have been reported

Idiopathic retroperitoneal fibrosis involving a unilateral renal sinus: A case report and literature review

Energy Technology Data Exchange (ETDEWEB)

Lee, Seul Bi; Yoon, Jung Hee; Kim, Seung Ho; Lee, Ye Daum; Kim, Suk Jung; Lim, Yun Jung; Jung, Hyun Kyung; Lee, Jin Soo [Dept. of Radiology, Haeundae Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of)

2016-06-15

Idiopathic retroperitoneal fibrosis (RPF) is a rare disease entity and its etiology is uncertain. We report two similar cases which showed an uncommon presentation of idiopathic RPF. A 66-year-old woman and an 80-year-old man presented with incidental findings of left renal pelvic mass-like lesions. Computed tomography revealed a soft tissue density mass replacing the left renal pelvis, which was suspicious for renal pelvic cancer, and the diagnosis of idiopathic RPF was surgically confirmed. To the best of our knowledge, a few cases of idiopathic RPF presenting with features of a localized unilateral renal pelvic mass mimicking renal pelvic cancer have been reported.

Commissioning of the 400 MHz LHC RF System

CERN Document Server

Ciapala, Edmond; Baudrenghien, P; Brunner, O; Butterworth, A; Linnecar, T; Maesen, P; Molendijk, J; Montesinos, E; Valuch, D; Weierud, F

2008-01-01

The installation of the 400 MHz superconducting RF system in LHC is finished and commissioning is under way. The final RF system comprises four cryo-modules each with four cavities in the LHC tunnel straight section round IP4. Also underground in an adjacent cavern shielded from the main tunnel are the sixteen 300 kW klystron RF power sources with their high voltage bunkers, two Faraday cages containing RF feedback and beam control electronics, and racks containing all the slow controls. The system and the experience gained during commissioning will be described. In particular, results from conditioning the cavities and their movable main power couplers and the setting up of the low level RF feedbacks will be presented.

Short range RF communication for jet engine control

Science.gov (United States)

Sexton, Daniel White (Inventor); Hershey, John Erik (Inventor)

2007-01-01

A method transmitting a message over at least one of a plurality of radio frequency (RF) channels of an RF communications network is provided. The method comprises the steps of detecting a presence of jamming pulses in the at least one of the plurality of RF channels. The characteristics of the jamming pulses in the at least one of the plurality of RF channels is determined wherein the determined characteristics define at least interstices between the jamming pulses. The message is transmitted over the at least one of the plurality of RF channels wherein the message is transmitted within the interstices of the jamming pulse determined from the step of determining characteristics of the jamming pulses.

Physical Layer Security Enhancement in Multiuser Mixed RF#x002F;FSO Relay Networks under RF Interference

KAUST Repository

El-Malek, Ahmed H. Abd; Salhab, Anas M.; Zummo, Salam A.; Alouini, Mohamed-Slim

2017-01-01

In this paper, the impact of radio frequency (RF) co-channel interference (CCI) on the performance of multiuser (MU) mixed RF#x002F;free space optical (FSO) relay network with opportunistic user scheduling is studied. In the considered system, a user is opportunistically selected to communicate with a single destination through an amplify-and- forward (AF) relay in the presence of a single passive eavesdropper. The RF#x002F;FSO channel models are assumed to follow Rayleigh#x002F;Gamma-Gamma fading models, respectively with pointing errors and identical RF CCI signals. Exact closed-form expression for the system outage probability is derived. Then, an asymptotic expression for the outage probability is obtained at the high signal- to-interference-plus-noise ratio (SINR) regime. The asymptotic results are used to formulate a power allocation problem to obtain optimal RF transmission power. Then, the secrecy performance is studied in the presence of CCI at both the authorized relay and eavesdropper by obtaining exact and asymptotic closed-form expressions for the intercept probability. The derived analytical formulas herein are supported by numerical and simulation results to clarify the main contributions of the work.

Physical Layer Security Enhancement in Multiuser Mixed RF#x002F;FSO Relay Networks under RF Interference

KAUST Repository

El-Malek, Ahmed H. Abd

2017-05-12

In this paper, the impact of radio frequency (RF) co-channel interference (CCI) on the performance of multiuser (MU) mixed RF#x002F;free space optical (FSO) relay network with opportunistic user scheduling is studied. In the considered system, a user is opportunistically selected to communicate with a single destination through an amplify-and- forward (AF) relay in the presence of a single passive eavesdropper. The RF#x002F;FSO channel models are assumed to follow Rayleigh#x002F;Gamma-Gamma fading models, respectively with pointing errors and identical RF CCI signals. Exact closed-form expression for the system outage probability is derived. Then, an asymptotic expression for the outage probability is obtained at the high signal- to-interference-plus-noise ratio (SINR) regime. The asymptotic results are used to formulate a power allocation problem to obtain optimal RF transmission power. Then, the secrecy performance is studied in the presence of CCI at both the authorized relay and eavesdropper by obtaining exact and asymptotic closed-form expressions for the intercept probability. The derived analytical formulas herein are supported by numerical and simulation results to clarify the main contributions of the work.

Performance Analysis of RF-FSO Multi-Hop Networks

KAUST Repository

Makki, Behrooz

2017-05-12

We study the performance of multi-hop networks composed of millimeter wave (MMW)-based radio frequency (RF) and free-space optical (FSO) links. The results are obtained in the cases with and without hybrid automatic repeat request (HARQ). Taking the MMW characteristics of the RF links into account, we derive closed-form expressions for the network outage probability. We also evaluate the effect of various parameters such as power amplifiers efficiency, number of antennas as well as different coherence times of the RF and the FSO links on the system performance. Finally, we present mappings between the performance of RF- FSO multi-hop networks and the ones using only the RF- or the FSO-based communication, in the sense that with appropriate parameter settings the same outage probability is achieved in these setups. The results show the efficiency of the RF-FSO setups in different conditions. Moreover, the HARQ can effectively improve the outage probability/energy efficiency, and compensate the effect of hardware impairments in RF-FSO networks. For common parameter settings of the RF-FSO dual- hop networks, outage probability 10^{-4} and code rate 3 nats-per-channel-use, the implementation of HARQ with a maximum of 2 and 3 retransmissions reduces the required power, compared to the cases with no HARQ, by 13 and 17 dB, respectively.

CAT/RF Simulation Lessons Learned

Science.gov (United States)

2003-06-11

IVSS-2003-MAS-7 CAT /RF Simulation Lessons Learned Christopher Mocnik Vetronics Technology Area, RDECOM TARDEC Tim Lee DCS Corporation...developed a re- configurable Unmanned Ground Vehicle (UGV) simulation for the Crew integration and Automation Test bed ( CAT ) and Robotics Follower (RF...Advanced Technology Demonstration (ATD) experiments. This simulation was developed as a component of the Embedded Simulation System (ESS) of the CAT

Retroperitoneal Endometriosis: A Possible Cause of False Positive Finding at 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography

International Nuclear Information System (INIS)

Maffione, Anna Margherita; Panzavolta, Riccardo; Lisato, Laura Camilla; Ballotta, Maria; D'Isanto, Mariangela Zanforlini; Rubello, Domenico

2015-01-01

Endometriosis is a frequent and clinically relevant problem in young women. Laparoscopy is still the gold standard for the diagnosis of endometriosis, but frequently both morphologic and functional imaging techniques are involved in the diagnostic course before achieving a conclusive diagnosis. We present a case of a patient affected by infiltrating retroperitoneal endometriosis falsely interpreted as a malignant mass by contrast-enhanced magnetic resonance imaging and 18 F-fluorodeoxyglucose positron emission tomography/computed tomography

Development and advances in conventional high power RF systems

International Nuclear Information System (INIS)

Wilson, P.B.

1995-06-01

The development of rf systems capable of producing high peak power (hundreds of megawatts) at relatively short pulse lengths (0.1--5 microseconds) is currently being driven mainly by the requirements of future high energy linear colliders, although there may be applications to industrial, medical and research linacs as well. The production of high peak power rf typically involves four basic elements: a power supply to convert ac from the ''wall plug'' to dc; a modulator, or some sort of switching element, to produce pulsed dc power; an rf source to convert the pulsed dc to pulsed rf power; and possibly an rf pulse compression system to further enhance the peak rf power. Each element in this rf chain from wall plug to accelerating structure must perform with high efficiency in a linear collider application, such that the overall system efficiency is 30% or more. Basic design concepts are discussed for klystrons, modulators and rf pulse compression systems, and their present design status is summarized for applications to proposed linear colliders

47 CFR 27.52 - RF safety.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false RF safety. 27.52 Section 27.52 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Technical Standards § 27.52 RF safety. Licensees and manufacturers are subject to the...

Superconducting RF for energy-recovery linacs

International Nuclear Information System (INIS)

Liepe, M.; Knobloch, J.

2006-01-01

Since superconducting RF for particle accelerators made its first appearance in the 1970s, it has found highly successful application in a variety of machines. Recent progress in this technology has made so-called Energy-Recovery Linacs (ERLs)-originally proposed in 1965-feasible, and interest in this type of machine has increased enormously. A superconducting linac is the driving heart of ERLs, and emittance preservation and cost efficiency is of utmost importance. The resulting challenges for the superconducting cavity technology and RF field control are manifold. In March 2005 the first international workshop on ERLs was held at Newport News, VA, to explore the potential of ERLs and to discuss machine-physics and technology challenges and their solutions. This paper reviews the state-of-the-art in superconducting RF and RF control for ERLs, and summarizes the discussions of the SRF working group on this technology during the ERL2005 workshop

Frequency control of RF booster cavity in TRIUMF

International Nuclear Information System (INIS)

Fong, K.; Laverty, M.

1993-01-01

A booster is used in the TRIUMF cyclotron to increase the energy gain per turn for beam orbits corresponding to energies greater than 370 MeV. It operates at 92.24 MHz, the 4 th harmonic of the cyclotron main rf, and at a nominal voltage of 150 kV. Excitation is provided by a 90 kW rf system that is phase locked to the main rf. When the main rf is interrupted due to sparking or other causes, a controller built into the low frequency source of the booster rf system disables the phase-locked loop, and reconfigures the source as a temperature stabilized oscillator operating at the last locked frequency. When the cyclotron rf is restored it usually will be at different frequency. The oscillator tunes automatically to this new frequency. The acquisition time is extended by the controller to match the response time of the mechanical tuner in the cavity

Microwave RF antennas and circuits nonlinearity applications in engineering

CERN Document Server

Aluf, Ofer

2017-01-01

This book describes a new concept for analyzing RF/microwave circuits, which includes RF/microwave antennas. The book is unique in its emphasis on practical and innovative microwave RF engineering applications. The analysis is based on nonlinear dynamics and chaos models and shows comprehensive benefits and results. All conceptual RF microwave circuits and antennas are innovative and can be broadly implemented in engineering applications. Given the dynamics of RF microwave circuits and antennas, they are suitable for use in a broad range of applications. The book presents analytical methods for microwave RF antennas and circuit analysis, concrete examples, and geometric examples. The analysis is developed systematically, starting with basic differential equations and their bifurcations, and subsequently moving on to fixed point analysis, limit cycles and their bifurcations. Engineering applications include microwave RF circuits and antennas in a variety of topological structures, RFID ICs and antennas, micros...

Embedded control system for high power RF amplifiers

International Nuclear Information System (INIS)

Sharma, Deepak Kumar; Gupta, Alok Kumar; Jain, Akhilesh; Hannurkar, P.R.

2011-01-01

RF power devices are usually very sensitive to overheat and reflected RF power; hence a protective interlock system is required to be embedded with high power solid state RF amplifiers. The solid state RF amplifiers have salient features of graceful degradation and very low mean time to repair (MTTR). In order to exploit these features in favour of lowest system downtime, a real-time control system is embedded with high power RF amplifiers. The control system is developed with the features of monitoring, measurement and network publishing of various parameters, historical data logging, alarm generation, displaying data to the operator and tripping the system in case of any interlock failure. This paper discusses the design philosophy, features, functions and implementation details of the embedded control system. (author)

47 CFR 95.1125 - RF safety.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false RF safety. 95.1125 Section 95.1125 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PERSONAL RADIO SERVICES Wireless Medical Telemetry Service (WMTS) General Provisions § 95.1125 RF safety. Portable devices...

Spurious RF signals emitted by mini-UAVs

Science.gov (United States)

Schleijpen, Ric (H. M. A.); Voogt, Vincent; Zwamborn, Peter; van den Oever, Jaap

2016-10-01

This paper presents experimental work on the detection of spurious RF emissions of mini Unmanned Aerial Vehicles (mini-UAV). Many recent events have shown that mini-UAVs can be considered as a potential threat for civil security. For this reason the detection of mini-UAVs has become of interest to the sensor community. The detection, classification and identification chain can take advantage of different sensor technologies. Apart from the signatures used by radar and electro-optical sensor systems, the UAV also emits RF signals. These RF signatures can be split in intentional signals for communication with the operator and un-intentional RF signals emitted by the UAV. These unintentional or spurious RF emissions are very weak but could be used to discriminate potential UAV detections from false alarms. The goal of this research was to assess the potential of exploiting spurious emissions in the classification and identification chain of mini-UAVs. It was already known that spurious signals are very weak, but the focus was on the question whether the emission pattern could be correlated to the behaviour of the UAV. In this paper experimental examples of spurious RF emission for different types of mini-UAVs and their correlation with the electronic circuits in the UAVs will be shown

The TESLA RF System

International Nuclear Information System (INIS)

Choroba, S.

2003-01-01

The TESLA project proposed by the TESLA collaboration in 2001 is a 500 to 800GeV e+/e- linear collider with integrated free electron laser facility. The accelerator is based on superconducting cavity technology. Approximately 20000 superconducting cavities operated at 1.3GHz with a gradient of 23.4MV/m or 35MV/m will be required to achieve the energy of 500GeV or 800GeV respectively. For 500GeV ∼600 RF stations each generating 10MW of RF power at 1.3GHz at a pulse duration of 1.37ms and a repetition rate of 5 or 10Hz are required. The original TESLA design was modified in 2002 and now includes a dedicated 20GeV electron accelerator in a separate tunnel for free electron laser application. The TESLA XFEL will provide XFEL radiation of unprecedented peak brilliance and full transverse coherence in the wavelength range of 0.1 to 6.4nm at a pulse duration of 100fs. The technology of both accelerators, the TESLA linear collider and the XFEL, will be identical, however the number of superconducting cavities and RF stations for the XFEL will be reduced to 936 and 26 respectively. This paper describes the layout of the entire RF system of the TESLA linear collider and the TESLA XFEL and gives an overview of its various subsystems and components

RF Control System Upgrade at CAMD

CERN Document Server

Suller, Victor P; Jines, Paul; Launey, Daren

2005-01-01

A description is given of the new control system for the RF system of the CAMD light source. The new design being implemented brings all RF signals into the data acquisition system via a modular, custom made, RF detector and renders the amplitude and tune control loops in the VME computer. On line calculations ensure monitoring of proper operation and display the information to the user in an efficient way. In addition, an advanced load impedance monitoring diagnostic has been implemented, being displayed as a Smith Chart, which is based on the system used at the SRS in Daresbury, England.

EXCESS RF POWER REQUIRED FOR RF CONTROL OF THE SPALLATION NEUTRON SOURCE (SNS) LINAC, A PULSED HIGH-INTENSITY SUPERCONDUCTING PROTON ACCELERATOR

International Nuclear Information System (INIS)

Lynch, M.; Kwon, S.

2001-01-01

A high-intensity proton linac, such as that being planned for the SNS, requires accurate RF control of cavity fields for the entire pulse in order to avoid beam spill. The current design requirement for the SNS is RF field stability within ±0.5% and ±0.5 o [1]. This RF control capability is achieved by the control electronics using the excess RF power to correct disturbances. To minimize the initial capital costs, the RF system is designed with 'just enough' RF power. All the usual disturbances exist, such as beam noise, klystron/HVPS noise, coupler imperfections, transport losses, turn-on and turn-off transients, etc. As a superconducting linac, there are added disturbances of large magnitude, including Lorentz detuning and microphonics. The effects of these disturbances and the power required to correct them are estimated, and the result shows that the highest power systems in the SNS have just enough margin, with little or no excess margin

SQIF Arrays as RF Sensors (Briefing Charts)

National Research Council Canada - National Science Library

Yukon, Stanford P

2007-01-01

... (Superconducting Quantum Interference Filter) arrays may be employed as sensitive RF sensors. RF SQIF arrays fabricated with high Tc Josephson junctions can be cooled with small Sterling microcoolers...

On the frequency scalings of RF guns

International Nuclear Information System (INIS)

Lin, L.C.; Chen, S.C.; Wurtele, J.S.

1995-01-01

A frequency scaling law for RF guns is derived from the normalized Vlasov-Maxwell equations. It shows that higher frequency RF guns can generate higher brightness beams under the assumption that the accelerating gradient and all beam and structure parameters are scaled with the RF frequency. Numerical simulation results using MAGIC confirm the scaling law. A discussion of the range of applicability of the law is presented. copyright 1995 American Institute of Physics

Conventional RF system design

International Nuclear Information System (INIS)

Puglisi, M.

1994-01-01

The design of a conventional RF system is always complex and must fit the needs of the particular machine for which it is planned. It follows that many different design criteria should be considered and analyzed, thus exceeding the narrow limits of a lecture. For this reason only the fundamental components of an RF system, including the generators, are considered in this short seminar. The most common formulas are simply presented in the text, while their derivations are shown in the appendices to facilitate, if desired, a more advanced level of understanding. (orig.)

47 CFR 90.1335 - RF safety.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false RF safety. 90.1335 Section 90.1335 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Wireless Broadband Services in the 3650-3700 MHz Band § 90.1335 RF safety...

Adaptive RF front-ends for hand-held applications

CERN Document Server

van Bezooijen, Andre; van Roermund, Arthur

2010-01-01

The RF front-end - antenna combination is a vital part of a mobile phone because its performance is very relevant to the link quality between hand-set and cellular network base-stations. The RF front-end performance suffers from changes in operating environment, like hand-effects, that are often unpredictable. ""Adaptive RF Front-Ends for Hand-Held Applications"" presents an analysis on the impact of fluctuating environmental parameters. In order to overcome undesired behavior two different adaptive control methods are treated that make RF frond-ends more resilient: adaptive impedance control,

Method of electron emission control in RF guns

International Nuclear Information System (INIS)

Khodak, I.V.; Kushnir, V.A.

2001-01-01

The electron emission control method for a RF gun is considered.According to the main idea of the method,the additional resonance system is created in a cathode region where the RF field strength could be varied using the external pulse equipment. The additional resonance system is composed of a coaxial cavity coupled with a RF gun cylindrical cavity via an axial hole. Computed results of radiofrequency and electrodynamic performances of such a two-cavity system and results of the RF gun model pilot study are presented in. Results of particle dynamics simulation are described

Method of electron emission control in RF guns

CERN Document Server

Khodak, I V

2001-01-01

The electron emission control method for a RF gun is considered.According to the main idea of the method,the additional resonance system is created in a cathode region where the RF field strength could be varied using the external pulse equipment. The additional resonance system is composed of a coaxial cavity coupled with a RF gun cylindrical cavity via an axial hole. Computed results of radiofrequency and electrodynamic performances of such a two-cavity system and results of the RF gun model pilot study are presented in. Results of particle dynamics simulation are described.

Characterization of Energy Availability in RF Energy Harvesting Networks

Directory of Open Access Journals (Sweden)

Daniela Oliveira

2016-01-01

Full Text Available The multiple nodes forming a Radio Frequency (RF Energy Harvesting Network (RF-EHN have the capability of converting received electromagnetic RF signals in energy that can be used to power a network device (the energy harvester. Traditionally the RF signals are provided by high power transmitters (e.g., base stations operating in the neighborhood of the harvesters. Admitting that the transmitters are spatially distributed according to a spatial Poisson process, we start by characterizing the distribution of the RF power received by an energy harvester node. Considering Gamma shadowing and Rayleigh fading, we show that the received RF power can be approximated by the sum of multiple Gamma distributions with different scale and shape parameters. Using the distribution of the received RF power, we derive the probability of a node having enough energy to transmit a packet after a given amount of charging time. The RF power distribution and the probability of a harvester having enough energy to transmit a packet are validated through simulation. The numerical results obtained with the proposed analysis are close to the ones obtained through simulation, which confirms the accuracy of the proposed analysis.

ORIC RF system: preparation for HHIRF

International Nuclear Information System (INIS)

Mosko, S.W.; Rylander, J.D.; Schulze, G.K.

1977-01-01

The integration of the Oak Ridge Isochronous Cyclotron (ORIC) into the Holifield Heavy Ion Research Facility (HHIRF) requires several rf system modifications to permit injection of ion beams from the 25 MV tandem electrostatic accelerator into ORIC. A new dee eliminates structural interference with the injected beam path and provides an opportunity to improve the mechanical stability of the resonator and to reduce rf voltage gradients in areas susceptible to sparking. Space for structural improvements is realized by reducing the ion beam aperture from 4.8 cm to 2.4 cm. The complexity of the original ORIC rf power system was substantially reduced. A new broadband solid state driver amplifier between the frequency synthesizer and the main power amplifier eliminates most circuit tuning and permits the use of a new simplified dee rf voltage regulator loop. Most of the remaining instrumentation and control circuitry is TTL compatible and will eventually tie to the ORIC computer control system through a CAMAC interface

Global voltage control for the LEP RF system

International Nuclear Information System (INIS)

Ciapala, E.; Butterworth, A.; Peschardt, E.

1993-01-01

The LEG RF system is installed as independent 16 cavity units. In addition to the eight copper cavity units originally installed 12 units with super-conducting cavities are being added for the LEP200 energy upgrade. The total RF voltage determines the synchrotron tune (Qs) and must be controlled precisely during energy ramping. Local function generators in each of the RF units are pre-loaded such that when triggered simultaneously by ramp timing events transmitted over the general timing system the total voltage varies to give the Qs function required. A disadvantage is that loss of RF in a unit at any time after the loading process cannot be corrected. As the number of RF units increases automatic control of the total RF voltage and its distribution around LEP becomes desirable. A global voltage control system, based on a central VME controller, has recently been installed. It has direct and rapid access to the RF units over the LEP time division multiplexing system. Initial tests on operation and performance at fixed energy and during energy ramping are described, as well as the implementation of a Qs loop in which Qs can be set directly using on-line synchrotron frequency measurements

DESIGN OF A DC/RF PHOTOELECTRON GUN

International Nuclear Information System (INIS)

YU, D.; NEWSHAM, Y.; SMIRONOV, A.; YU, J.; SMEDLEY, J.; SRINIVASAN RAU, T.; LEWELLEN, J.; ZHOLENTS, A.

2003-01-01

An integrated dc/rf photoelectron gun produces a low-emittance beam by first rapidly accelerating electrons at a high gradient during a short (∼1 ns), high-voltage pulse, and then injecting the electrons into an rf cavity for subsequent acceleration. Simulations show that significant improvement of the emittance appears when a high field (∼ 0.5-1 GV/m) is applied to the cathode surface. An adjustable dc gap ((le) 1 mm) which can be integrated with an rf cavity is designed for initial testing at the Injector Test Stand at Argonne National Laboratory using an existing 70-kV pulse generator. Plans for additional experiments of an integrated dc/rf gun with a 250-kV pulse generator are being made

High power rf component testing for the NLC

International Nuclear Information System (INIS)

Vlieks, A.E.; Fowkes, W.R.; Loewen, R.J.; Tantawi, S.G.

1998-09-01

In the Next Linear Collider (NLC), the high power rf components must be capable of handling peak rf power levels in excess of 600 MW. In the current view of the NLC, even the rectangular waveguide components must transmit at least 300 MW rf power. At this power level, peak rf fields can greatly exceed 100 MV/m. The authors present recent results of high power tests performed at the Accelerator Structure Test Area (ASTA) at SLAC. These tests are designed to investigate the rf breakdown limits of several new components potentially useful for the NLC. In particular, the authors tested a new TE 01 --TE 10 circular to rectangular wrap-around mode converter, a modified (internal fin) Magic Tee hybrid, and an upgraded flower petal mode converter

Water cooling of RF structures

International Nuclear Information System (INIS)

Battersby, G.; Zach, M.

1994-06-01

We present computer codes for heat transfer in water cooled rf cavities. RF parameters obtained by SUPERFISH or analytically are operated on by a set of codes using PLOTDATA, a command-driven program developed and distributed by TRIUMF [1]. Emphasis is on practical solutions with designer's interactive input during the computations. Results presented in summary printouts and graphs include the temperature, flow, and pressure data. (authors). 4 refs., 4 figs

Unbalanced field RF electron gun

Science.gov (United States)

Hofler, Alicia

2013-11-12

A design for an RF electron gun having a gun cavity utilizing an unbalanced electric field arrangement. Essentially, the electric field in the first (partial) cell has higher field strength than the electric field in the second (full) cell of the electron gun. The accompanying method discloses the use of the unbalanced field arrangement in the operation of an RF electron gun in order to accelerate an electron beam.

A no-load RF calorimeter

Science.gov (United States)

Chernoff, R. C.

1975-01-01

The described device can be used to measure the output of any dc powered RF source. No dummy load is required for the measurements. The device is, therefore, called the 'no-load calorimeter' (NLC). The NLC measures the power actually fed to the antenna or another useful load. It is believed that the NLC can compete successfully with directional coupler type systems in measuring the output of high-power RF sources.

Status of 174 MHz RF system for BEP

International Nuclear Information System (INIS)

Biryuchevsky, Yu.A.; Gorniker, E.I.; Kendjebulatov, E.K.; Krutikhin, S.A.; Kurkin, G.Ya.; Petrov, V.M.; Pilan, A.M.

2012-01-01

The new RF system for the BEP storage ring (which is an injector of VEPP-2000 accelerating complex) will increase the particles energy in the BEP from 0.9 to 1 GeV. RF system operates at a frequency of 174 MHz and consists of an accelerating cavity, RF power generator and control system.

EM modeling of RF drive in DTL tank 4

International Nuclear Information System (INIS)

Kurennoy, Sergey S.

2012-01-01

A 3-D MicroWave Studio model for the RF drive in the LANSCE DTL tank 4 has been built. Both eigensolver and time-domain modeling are used to evaluate maximal fields in the drive module and RF coupling. The LANSCE DTL tank 4 has recently been experiencing RF problems, which may or may not be related to its replaced RF coupler. This situation stimulated a request by Dan Rees to provide EM modeling of the RF drive in the DTL tank 4 (T4). Jim O'Hara provided a CAD model that was imported into the CST Microwave Studio (MWS) and after some modifications became a part of a simplified MWS model of the T4 RF drive. This technical note describes the model and presents simulation results.

Slice-selective RF pulses for in vivo B1+ inhomogeneity mitigation at 7 tesla using parallel RF excitation with a 16-element coil.

Science.gov (United States)

Setsompop, Kawin; Alagappan, Vijayanand; Gagoski, Borjan; Witzel, Thomas; Polimeni, Jonathan; Potthast, Andreas; Hebrank, Franz; Fontius, Ulrich; Schmitt, Franz; Wald, Lawrence L; Adalsteinsson, Elfar

2008-12-01

Slice-selective RF waveforms that mitigate severe B1+ inhomogeneity at 7 Tesla using parallel excitation were designed and validated in a water phantom and human studies on six subjects using a 16-element degenerate stripline array coil driven with a butler matrix to utilize the eight most favorable birdcage modes. The parallel RF waveform design applied magnitude least-squares (MLS) criteria with an optimized k-space excitation trajectory to significantly improve profile uniformity compared to conventional least-squares (LS) designs. Parallel excitation RF pulses designed to excite a uniform in-plane flip angle (FA) with slice selection in the z-direction were demonstrated and compared with conventional sinc-pulse excitation and RF shimming. In all cases, the parallel RF excitation significantly mitigated the effects of inhomogeneous B1+ on the excitation FA. The optimized parallel RF pulses for human B1+ mitigation were only 67% longer than a conventional sinc-based excitation, but significantly outperformed RF shimming. For example the standard deviations (SDs) of the in-plane FA (averaged over six human studies) were 16.7% for conventional sinc excitation, 13.3% for RF shimming, and 7.6% for parallel excitation. This work demonstrates that excitations with parallel RF systems can provide slice selection with spatially uniform FAs at high field strengths with only a small pulse-duration penalty. (c) 2008 Wiley-Liss, Inc.

Development of C-band High-Power Mix-Mode RF Window

CERN Document Server

Michizono, S; Matsumoto, T; Nakao, K; Takenaka, T

2004-01-01

High power c-band (5712 MHz) rf system (40 MW, 2 μs, 50 Hz) is under consideration for the electron-linac upgrade aimed for the super KEKB project. An rf window, which isolates the vacuum and pass the rf power, is one of the most important components for the rf system. The window consists of a ceramic disk and a pill-box housing. The mix-mode rf window is designed so as to decrease the electric field on the periphery of the ceramic disk. A resonant ring is assembled in order to examine the high-power transmission test. The window was tested up to the transmission power of 160 MW. The rf losses are also measured during the rf operation.

Massive retroperitoneal haemorrhage after extracorporeal shock wave lithotripsy (ESWL).

Science.gov (United States)

Inoue, Hiromasa; Kamphausen, Thomas; Bajanowski, Thomas; Trübner, Kurt

2011-01-01

A 76-year-old male suffering from nephrolithiasis developed a shock syndrome 5 days after extracorporal shock wave lithotripsy (ESWL). CT scan of the abdomen showed massive haemorrhage around the right kidney. Although nephrectomy was performed immediately, the haemorrhage could not be controlled. Numerous units of erythrocytes were transfused, but the patient died. The autopsy revealed massive retroperitoneal haemorrhage around the right kidney. The kidney showed a subcapsular haematoma and a rupture of the capsule. The right renal artery was dissected. The inferior vena cava was lacerated. Accordingly, a hemorrhagic shock as the cause of death was determined, which might mainly have resulted from the laceration of the inferior vena cava due to ESWL. ESWL seems to be a relatively non-invasive modality, but one of its severe complications is perirenal hematoma. The injuries of the blood vessels might have been caused by excessive shock waves. Subsequently, anticoagulation therapy had been resumed 3 days after EWSL, which might have triggered the haemorrhage. Physicians should note that a haemorrhage after an ESWL can occur and they should pay attention to the postoperative management in aged individuals especially when they are under anticoagulation therapy.

rf beam-current, -phase, and -position monitors

International Nuclear Information System (INIS)

Young, L.

1984-01-01

A prototype rf beam monitor has been tested on the Racetrack Microtron's (RTM) 100 kV injector beam line at the National Bureau of Standards (NBS). This beam monitor is capable of measuring the current, the relative phase, and the position of the beam. The beam is bunched at 2380 MHz for acceleration by the linac in the injector beam line. This train of beam bunches passing through the beam monitor cavities excites the cavities at this resonance frequency of 2380 MHz. Probes in the cavities couple some of the beam-excited rf power out of the cavities. This rf power can be amplified if necessary and then analyzed by a double balanced mixer (DBM). The DBM can also be used as a phase detector. The effective shunt impedance of the cavities was measured with the CW beam. For the position monitor cavity, the shunt impedance is proportional to the displacement from the axis. The measured response of the prototype rf beam current monitor setup is a linear function of beam current. Response of the rf beam-position monitor is also shown

RF Anechoic Chambers, Tri-Service Research Laboratory

Data.gov (United States)

Federal Laboratory Consortium — In collaboration with the Navy, there are 12 RF Anechoic and static free exposure chambers located at TSRL. These chambers cover the majority of the RF spectrum and...

An investigation of the DC and RF performance of InP DHBTs transferred to RF CMOS wafer substrate

Science.gov (United States)

Ren, Kun; Zheng, Jiachen; Lu, Haiyan; Liu, Jun; Wu, Lishu; Zhou, Wenyong; Cheng, Wei

2018-05-01

This paper investigated the DC and RF performance of the InP double heterojunction bipolar transistors (DHBTs) transferred to RF CMOS wafer substrate. The measurement results show that the maximum values of the DC current gain of a substrate transferred device had one emitter finger, of 0.8 μm in width and 5 μm in length, are changed unobviously, while the cut-off frequency and the maximum oscillation frequency are decreased from 220 to 171 GHz and from 204 to 154 GHz, respectively. In order to have a detailed insight on the degradation of the RF performance, small-signal models for the InP DHBT before and after substrate transferred are presented and comparably extracted. The extracted results show that the degradation of the RF performance of the device transferred to RF CMOS wafer substrate are mainly caused by the additional introduced substrate parasitics and the increase of the capacitive parasitics induced by the substrate transfer process itself. Project supported by the National Natural Science Foundation of China (No. 61331006) and the Natural Science Foundation of Zhejiang Province (No. Y14F010017).

Case report: Retroperitoneal biliary fluid collections secondary to common bile duct rupture - an unusual complication of choledocholithiasis in a child

International Nuclear Information System (INIS)

Rastogi, Rajul; Rastogi, Vaibhav

2008-01-01

Rupture of the common bile duct (CBD) in a child secondary to choledocholithiasis is a rare event. In this article, the authors describe a child who presented with an acute abdomen due to CBD rupture, with subsequent acute retroperitoneal fluid collections, all diagnosed preoperatively on CT scan. The aim of this article is to show the pathways that such collections can take in the retroperitoneum

The Bohm criterion for rf discharges

International Nuclear Information System (INIS)

Meijer, P.M.; Goedheer, W.J.

1991-01-01

The well-known dc Bohm criterion is extended to rf discharges. Both low- (ω rf much-lt ω pi ) and high-(ω pi much-lt ω rf ) frequency regimes are considered. For low frequencies, the dc Bohm criterion holds. This criterion states that the initial energy of the ions entering the sheath must exceed a limit in order to obtain a stable sheath. For high frequencies, a modified limit is derived, which is somewhat lower than that of the dc Bohm criterion. The resulting ion current density in a high-frequency sheath is only a few percent lower than that for the dc case

rf coupler technology for fusion applications

International Nuclear Information System (INIS)

Hoffman, D.J.

1983-01-01

Radio frequency (rf) oscillations at critical frequencies have successfully provided a means to convey power to fusion plasmas due to the electrical-magnetic properties of the plasma. While large rf systems to couple power to the plasma have been designed, built, and tested, the main link to the plasma, the coupler, is still in an evolutionary stage of development. Design and fabrication of optimal antennas for fusion applications are complicated by incomplete characterizations of the harsh plasma environment and of coupling mechanisms. A brief description of rf coupler technology required for plasma conditions is presented along with an assessment of the status and goals of coupler development

Longitudinal beam dynamics with rf noise

International Nuclear Information System (INIS)

Shih, H.J.; Ellison, J.A.; Cogburn, R.; Newberger, B.S.

1993-06-01

The Dome-Krinsky-Wang (DKW) diffusion-inaction theory for rf-noise-induced emittance dilution is reviewed and related to recent work on the approximation of stochastic processes by Markov processes. An accurate and efficient numerical procedure is developed to integrate the diffusion equation of the DKW theory. Tracking simulations are undertaken to check the validity of the theory in the parameter range of the Superconducting Super Collider (SSC) and to provide additional information. The study of effects of rf noise is applied to two problems of interest at the SSC: (1) determination of noise tolerance levels in the rf system, and (2) feasibility of beam extraction using crystal channeling

RF high voltage performance of RF transmission line components on the DIII-D Fast Wave Current Drive (FWCD) system

International Nuclear Information System (INIS)

Ferguson, S.W.; Callis, R.W.; Cary, W.P.; Phelps, D.A.; Ponce, D.; Baity, F.W.; Barber, G.

1995-01-01

The performance of the high voltage rf components of the DIII-D Fast Wave Current Drive System (FWCD) have been evaluated under various conditions of insulator configuration, insulator material, insulating gas and gas pressure. The insulator materials that have been investigated are alumina, steatite, pyrex, quartz, and teflon. The results of this evaluation are discussed in this paper. Additionally a rf high potter was developed to aid in the evaluation of rf high voltage components. The high potter consists of a 50 Ω, 1/4 wavelength cavity with a variable position short and a 50 ohm matched tap at one end of the cavity. With this configuration rf voltages were generated in excess of 100 kVp in the frequency range 30 to 60 MHz

RF high voltage performance of RF transmission line components on the DIII-D Fast Wave Current Drive (FWCD) System

International Nuclear Information System (INIS)

Ferguson, S.W.; Callis, R.W.; Cary, W.P.; Phelps, D.A.; Ponce, D.; Baity, F.W.; Barber, G.

1995-12-01

The performance of the high voltage rf components of the DIII-D Fast Wave Current Drive System (FWCD) have been evaluated under various conditions of insulator configuration, insulator material, insulating gas and gas pressure. The insulator materials that have been investigated are alumina, steatite, pyrex, quartz, and teflon. The results of this evaluation are discussed in this paper. Additionally a rf high potter was developed to aid in the evaluation of rf high voltage components. The high potter consists of a 50 Ω, 1/4 wavelength cavity with a variable position short and a 50 ohm matched tap at one end of the cavity. With this configuration rf voltages were generated in excess of 100 kVp in the frequency range 30 to 60 MHz

47 CFR 101.1525 - RF safety.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false RF safety. 101.1525 Section 101.1525 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Service and Technical Rules for the 70/80/90 GHz Bands § 101.1525 RF safety. Licensees in the 70...

Simulation of synchrotron motion with rf noise

International Nuclear Information System (INIS)

Leemann, B.T.; Forest, E.; Chattopadhyay, S.

1986-08-01

The theoretical formulation is described that is behind an algorithm for synchrotron phase-space tracking with rf noise and some preliminary simulation results of bunch diffusion under rf noise obtained by actual tracking

Protocol Design and Performance Analysis of Multiuser Mixed RF and Hybrid FSO/RF Relaying With Buffers

KAUST Repository

Al-Eryani, Yasser F.

2018-03-07

In this paper, a multiuser mixed radio frequency (RF) and hybrid free-space optical (FSO)/RF system is considered, where multiple mobile users transmit their data to an intermediate decode-and-forward relay node through RF links using a virtual multiple-input multipleoutput (MIMO) system, and the relay node forwards the multiplexed data of all users through a FSO link that is supported by a RF MIMO backup system to the destination. The relay node is equipped with a buffer in the physical layer for temporal storage of the users\\' data until the best channel conditions at the relay-destination link aremet. For this communication setup, we first propose a transmission protocol that achieves a multiplexing gain through a virtual MIMO system. After that, we derive closed-form expressions for the end-to-end outage probability, asymptotic outage probability, average symbol error rate, and the ergodic capacity when considering the delay-tolerant (finite buffer size) scenario. The results show that buffering in the physical layer provides a significant enhancement to the system performance (outage, error rate, and ergodic capacity). It is also found that pointing error and severe weather turbulence conditions become more tolerable with the existence of the relay\\'s buffer and RF backup link (in the second hop). In addition, the proposed virtual MIMO scheme shows a significant performance enhancement at a high number of receiving antennas, which introduces potential lowcomplexity diversity gain-based massive MIMO schemes.

Protocol Design and Performance Analysis of Multiuser Mixed RF and Hybrid FSO/RF Relaying With Buffers

KAUST Repository

Al-Eryani, Yasser F.; Salhab, Anas; Zummo, Salam A.; Alouini, Mohamed-Slim

2018-01-01

In this paper, a multiuser mixed radio frequency (RF) and hybrid free-space optical (FSO)/RF system is considered, where multiple mobile users transmit their data to an intermediate decode-and-forward relay node through RF links using a virtual multiple-input multipleoutput (MIMO) system, and the relay node forwards the multiplexed data of all users through a FSO link that is supported by a RF MIMO backup system to the destination. The relay node is equipped with a buffer in the physical layer for temporal storage of the users' data until the best channel conditions at the relay-destination link aremet. For this communication setup, we first propose a transmission protocol that achieves a multiplexing gain through a virtual MIMO system. After that, we derive closed-form expressions for the end-to-end outage probability, asymptotic outage probability, average symbol error rate, and the ergodic capacity when considering the delay-tolerant (finite buffer size) scenario. The results show that buffering in the physical layer provides a significant enhancement to the system performance (outage, error rate, and ergodic capacity). It is also found that pointing error and severe weather turbulence conditions become more tolerable with the existence of the relay's buffer and RF backup link (in the second hop). In addition, the proposed virtual MIMO scheme shows a significant performance enhancement at a high number of receiving antennas, which introduces potential lowcomplexity diversity gain-based massive MIMO schemes.

Application and analysis of retroperitoneal laparoscopic partial nephrectomy with sequential segmental renal artery clamping for patients with multiple renal tumor: initial experience.

Science.gov (United States)

Zhu, Jundong; Jiang, Fan; Li, Pu; Shao, Pengfei; Liang, Chao; Xu, Aiming; Miao, Chenkui; Qin, Chao; Wang, Zengjun; Yin, Changjun

2017-09-11

To explore the feasibility and safety of retroperitoneal laparoscopic partial nephrectomy with sequential segmental renal artery clamping for the patients with multiple renal tumor of who have solitary kidney or contralateral kidney insufficiency. Nine patients who have undergone retroperitoneal laparoscopic partial nephrectomy with sequential segmental renal artery clamping between October 2010 and January 2017 were retrospectively analyzed. Clinical materials and parameters during and after the operation were summarized. Nineteen tumors were resected in nine patients and the operations were all successful. The operation time ranged from 100 to 180 min (125 min); clamping time of segmental renal artery was 10 ~ 30 min (23 min); the amount of blood loss during the operation was 120 ~ 330 ml (190 ml); hospital stay after the operation is 3 ~ 6d (5d). There was no complication during the perioperative period, and the pathology diagnosis after the surgery showed that there were 13 renal clear cell carcinomas, two papillary carcinoma and four perivascular epithelioid cell tumors with negative margins from the 19 tumors. All patients were followed up for 3 ~ 60 months, and no local recurrence or metastasis was detected. At 3-month post-operation follow-up, the mean serum creatinine was 148.6 ± 28.1 μmol/L (p = 0.107), an increase of 3.0 μmol/L from preoperative baseline. For the patients with multiple renal tumors and solitary kidney or contralateral kidney insufficiency, retroperitoneal laparoscopic partial nephrectomy with sequential segmental renal artery clamping was feasible and safe, which minimized the warm ischemia injury to the kidney and preserved the renal function effectively.

Superconductor Digital-RF Receiver Systems

Science.gov (United States)

Mukhanov, Oleg A.; Kirichenko, Dmitri; Vernik, Igor V.; Filippov, Timur V.; Kirichenko, Alexander; Webber, Robert; Dotsenko, Vladimir; Talalaevskii, Andrei; Tang, Jia Cao; Sahu, Anubhav; Shevchenko, Pavel; Miller, Robert; Kaplan, Steven B.; Sarwana, Saad; Gupta, Deepnarayan

Digital superconductor electronics has been experiencing rapid maturation with the emergence of smaller-scale, lower-cost communications applications which became the major technology drivers. These applications are primarily in the area of wireless communications, radar, and surveillance as well as in imaging and sensor systems. In these areas, the fundamental advantages of superconductivity translate into system benefits through novel Digital-RF architectures with direct digitization of wide band, high frequency radio frequency (RF) signals. At the same time the availability of relatively small 4K cryocoolers has lowered the foremost market barrier for cryogenically-cooled digital electronic systems. Recently, we have achieved a major breakthrough in the development, demonstration, and successful delivery of the cryocooled superconductor digital-RF receivers directly digitizing signals in a broad range from kilohertz to gigahertz. These essentially hybrid-technology systems combine a variety of superconductor and semiconductor technologies packaged with two-stage commercial cryocoolers: cryogenic Nb mixed-signal and digital circuits based on Rapid Single Flux Quantum (RSFQ) technology, room-temperature amplifiers, FPGA processing and control circuitry. The demonstrated cryocooled digital-RF systems are the world's first and fastest directly digitizing receivers operating with live satellite signals in X-band and performing signal acquisition in HF to L-band at ˜30GHz clock frequencies.

Analog techniques in CEBAF's RF control system

International Nuclear Information System (INIS)

Hovater, C.; Fugitt, J.

1989-01-01

Recent developments in high-speed analog technology have progressed into the areas of traditional RF technology. Diode related devices are being replaced by analog IC's in the CEBAF RF control system. Complex phase modulators and attenuators have been successfully tested at 70 MHz. They have three advantages over existing technology: lower cost, less temperature sensitivity, and more linearity. RF signal conditioning components and how to implement the new analog IC's will be covered in this paper. 4 refs., 5 figs

Analog techniques in CEBAF'S RF control system

International Nuclear Information System (INIS)

Hovater, C.; Fugitt, J.

1989-01-01

Recent developments in high-speed analog technology have progressed into the areas of traditional rf technology. Diode-related devices are being replaced by analog IC's in the CEBAF rf control system. Complex phase modulators and attenuators have been successfully tested at 70 MHz. They have three advantages over existing technology: lower cost, less temperature sensitivity, and more linearity. Rf signal conditioning components and how to implement the new analog IC's will be covered in this paper. 4 refs., 5 figs

Upgrade of the Cryogenic CERN RF Test Facility

CERN Document Server

Pirotte, O; Brunner, O; Inglese, V; Koettig, T; Maesen, P; Vullierme, B

2014-01-01

With the large number of superconducting radiofrequency (RF) cryomodules to be tested for the former LEP and the present LHC accelerator a RF test facility was erected early in the 1990’s in the largest cryogenic test facility at CERN located at Point 18. This facility consisted of four vertical test stands for single cavities and originally one and then two horizontal test benches for RF cryomodules operating at 4.5 K in saturated helium. CERN is presently working on the upgrade of its accelerator infrastructure, which requires new superconducting cavities operating below 2 K in saturated superfluid helium. Consequently, the RF test facility has been renewed in order to allow efficient cavity and cryomodule tests in superfluid helium and to improve its thermal performances. The new RF test facility is described and its performances are presented.

Upgrade of the cryogenic CERN RF test facility

International Nuclear Information System (INIS)

Pirotte, O.; Benda, V.; Brunner, O.; Inglese, V.; Maesen, P.; Vullierme, B.; Koettig, T.

2014-01-01

With the large number of superconducting radiofrequency (RF) cryomodules to be tested for the former LEP and the present LHC accelerator a RF test facility was erected early in the 1990’s in the largest cryogenic test facility at CERN located at Point 18. This facility consisted of four vertical test stands for single cavities and originally one and then two horizontal test benches for RF cryomodules operating at 4.5 K in saturated helium. CERN is presently working on the upgrade of its accelerator infrastructure, which requires new superconducting cavities operating below 2 K in saturated superfluid helium. Consequently, the RF test facility has been renewed in order to allow efficient cavity and cryomodule tests in superfluid helium and to improve its thermal performances. The new RF test facility is described and its performances are presented

The LEP RF Trip and Beam Loss Diagnostics System

CERN Document Server

Arnaudon, L; Beetham, G; Ciapala, Edmond; Juillard, J C; Olsen, R

2002-01-01

During the last years of operation the number of operationally independent RF stations distributed around LEP reached a total of 40. A serious difficulty when running at high energy and high beam intensities was to establish cause and effect in beam loss situations, where the trip of any single RF station would result in beam loss, rapidly producing further multiple RF station trips. For the last year of operation a fast post-mortem diagnostics system was developed to allow precise time-stamping of RF unit trips and beam intensity changes. The system was based on eight local DSP controlled fast acquisition and event recording units, one in each RF sector, connected to critical RF control signals and fast beam intensity monitors and synchronised by GPS. The acquisition units were armed and synchronised at the start of each fill. At the end of the fill the local time-stamped RF trip and beam intensity change history tables were recovered, events ordered and the results stored in a database for subsequent analys...

ACCELERATORS: RF system design and measurement of HIRF-CSRe

Science.gov (United States)

Xu, Zhe; Zhao, Hong-Wei; Wang, Chun-Xiao; Xia, Jia-Wen; Zhan, Wen-Long; Bian, Zhi-Bin

2009-05-01

An RF system for the CSRe (cooling storage experimental ring) is designed and manufactured domestically. The present paper mainly describes the RF system design in five main sections: ferrite ring, RF cavity, RF generator, low level system and cavity cooling. The cavity is based on a type of coaxial resonator which is shorted at the end with one gap and loaded with domestic ferrite rings. The RF generator is designed in the push-pull mode and the low level control system is based on a DSP+FGPA+DDS+USB interface and has three feedback loops. Finally we give the results of the measurement on our system.

Alternative RF coupling configurations for H− ion sources

International Nuclear Information System (INIS)

Briefi, S.; Fantz, U.; Gutmann, P.

2015-01-01

RF heated sources for negative hydrogen ions both for fusion and accelerators require very high RF powers in order to achieve the required H − current what poses high demands on the RF generators and the RF circuit. Therefore it is highly desirable to improve the RF efficiency of the sources. This could be achieved by applying different RF coupling concepts than the currently used inductive coupling via a helical antenna, namely Helicon coupling or coupling via a planar ICP antenna enhanced with ferrites. In order to investigate the feasibility of these concepts, two small laboratory experiments have been set up. The PlanICE experiment, where the enhanced inductive coupling is going to be investigated, is currently under assembly. At the CHARLIE experiment systematic measurements concerning Helicon coupling in hydrogen and deuterium are carried out. The investigations show that a prominent feature of Helicon discharges occurs: the so-called low-field peak. This is a local improvement of the coupling efficiency at a magnetic field strength of a few mT which results in an increased electron density and dissociation degree. The full Helicon mode has not been achieved yet due to the limited available RF power and magnetic field strength but it might be sufficient for the application of the coupling concept to ion sources to operate the discharge in the low-field-peak region

Reduced dose uncertainty in MRI-based polymer gel dosimetry using parallel RF transmission with multiple RF sources

International Nuclear Information System (INIS)

Sang-Young Kim; Jung-Hoon Lee; Jin-Young Jung; Do-Wan Lee; Seu-Ran Lee; Bo-Young Choe; Hyeon-Man Baek; Korea University of Science and Technology, Daejeon; Dae-Hyun Kim; Jung-Whan Min; Ji-Yeon Park

2014-01-01

In this work, we present the feasibility of using a parallel RF transmit with multiple RF sources imaging method (MultiTransmit imaging) in polymer gel dosimetry. Image quality and B 1 field homogeneity was statistically better in the MultiTransmit imaging method than in conventional single source RF transmission imaging method. In particular, the standard uncertainty of R 2 was lower on the MultiTransmit images than on the conventional images. Furthermore, the MultiTransmit measurement showed improved dose resolution. Improved image quality and B 1 homogeneity results in reduced dose uncertainty, thereby suggesting the feasibility of MultiTransmit MR imaging in gel dosimetry. (author)

High power RF test of an 805 MHz RF cavity for a muon cooling channel

International Nuclear Information System (INIS)

Li, Derun; Corlett, J.; MacGill, R.; Rimmer, R.; Wallig, J.; Zisman, M.; Moretti, A.; Qian, Z.; Wu, V.; Summers, D.; Norem, J.

2002-01-01

We present recent high power RF test results on an 805 MHz cavity for a muon cooling experiment at Lab G in Fermilab. In order to achieve high accelerating gradient for large transverse emittance muon beams, the cavity design has adopted a pillbox like shape with 16 cm diameter beam iris covered by thin Be windows, which are demountable to allow for RF tests of different windows. The cavity body is made from copper with stiff stainless steel rings brazed to the cavity body for window attachments. View ports and RF probes are available for visual inspections of the surface of windows and cavity and measurement of the field gradient. Maximum of three thermo-couples can be attached to the windows for monitoring the temperature gradient on the windows caused by RF heating. The cavity was measured to have Q 0 of about 15,000 with copper windows and coupling constant of 1.3 before final assembling. A 12 MW peak power klystron is available at Lab G in Fermilab for the high power test. The cavity and coupler designs were performed using the MAFIA code in the frequency and the time domain. Numerical simulation results and cold test measurements on the cavity and coupler will be presented for comparisons

On the performance of hybrid RF and RF/FSO fixed gain dual-hop transmission systems

KAUST Repository

Ansari, Imran Shafique

2013-04-01

In this work, we present the performance analysis of a dual-branch transmission system composed of a direct radio frequency (RF) link and a dual-hop relay composed of asymmetric RF and free-space optical (FSO) links and compare it without having a direct RF path to see the effects of diversity on our system. The FSO link accounts for pointing errors and both types of detection techniques (i.e. indirect modulation/direct detection (IM/DD) as well as heterodyne detection). The performance is evaluated under the assumption of selection combining diversity scheme. RF links are modeled by Rayleigh fading distribution whereas the FSO link is modeled by a unified Gamma-Gamma fading distribution. Specifically, we derive new exact closed-form expressions for the cumulative distribution function, probability density function, moment generating function, and moments of the end-to-end signal-to-noise ratio of these systems in terms of the Meijer\\'s G function. We then capitalize on these results to offer new exact closed-form expressions for the outage probability, higher-order amount of fading, average error rate for binary and M-ary modulation schemes, and ergodic capacity, all in terms of Meijer\\'s G functions. All our new analytical results are also verified via computer-based Monte-Carlo simulations. © 2013 IEEE.

Design and manufacture of the RF power supply and RF transmission line for SANAEM project Prometheus

Science.gov (United States)

Turemen, G.; Ogur, S.; Ahiska, F.; Yasatekin, B.; Cicek, E.; Ozbey, A.; Kilic, I.; Unel, G.; Alacakir, A.

2017-08-01

A 1-5 MeV proton beamline is being built by the Turkish Atomic Energy Authority in collaboration with a number of graduate students from different universities. The primary goal of the project, is to acquire the design ability and manufacturing capability of all the components locally. SPP will be an accelerator and beam diagnostics test facility and it will also serve the detector development community with its low beam current. This paper discusses the design and construction of the RF power supply and the RF transmission line components such as its waveguide converters and its circulator. Additionally low and high power RF test results are presented to compare the performances of the locally produced components to the commercially available ones.

The RF voltage dependence of the electron sheath heating in low pressure capacitively coupled rf discharges

International Nuclear Information System (INIS)

Buddemeier, U.; Kortshagen, U.; Pukropski, I.

1995-01-01

In low pressure capacitively coupled RF discharges two competitive electron heating mechanisms have been discussed for some time now. At low pressures the stochastic sheath heating and for somewhat higher pressures the Joule heating in the bulk plasma have been proposed. When the pressure is increased at constant RF current density a transition from concave electron distribution functions (EDF) with a pronounced cold electron group to convex EDFs with a missing strong population of cold electrons is found. This transition was interpreted as the transition from dominant stochastic to dominant Joule heating. However, a different interpretation has been given by Kaganovich and Tsendin, who attributed the concave shaped EDFs to the spatially inhomogeneous RF field in combination with the nonlocality of the EDF

Femoral neuropathy due to retroperitoneal bleeding. A red herring in medicine complicates anticoagulant therapy and influences the Russian Communist Revolution (Crown Prince Alexis, Rasputin).

Science.gov (United States)

Willbanks, O L; Willbanks, S E

1983-02-01

Femoral neuropathy occurs when occult retroperitoneal bleeding impinges on the appropriate nerve roots. The syndrome involves the acute onset of groin and thigh pain with characteristic flexion and external rotation of the hip. It may mimic other conditions such as acute arterial occlusion. Thorough knowledge of the anatomy of the femoral nerve explains the clinical features and leads the clinician to suspect the occurrence of this syndrome. Three cases have been reviewed that exhibited this condition as a result of retroperitoneal bleeding, a complication of systemic heparin therapy. The hemophilia that afflicted Alexis, the Crown Prince of Russia and son of Tsar Nicholas and Tsarina Alexandra, resulted in this clinical syndrome. The consequences enabled the sinister starets, Gregory Rasputin, to become intimately involved with the royal family, influencing the response of the Tsar to the political events in Russia, thereby playing an important role in setting the stage for the 1917 Russian communist revolution.

Rheumatoid factor (RF)

Science.gov (United States)

... page: //medlineplus.gov/ency/article/003548.htm Rheumatoid factor (RF) To use the sharing features on this ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

Retroperitoneal arteriovenous malformation extending through the inferior vena cava into the heart and causing inferior vena cava dissection

International Nuclear Information System (INIS)

Sung, Yon Mi; Choe, Yeon Hyeon; Park, Seung Woo; Park, Pyo Won; Sung, Chang Ohk

2005-01-01

We present a case of retroperitoneal arteriovenous malformation extending through the inferior vena cava into the heart, which was associated with dissection of the inferior vena cava in a 32-year-old female. Computed tomography and magnetic resonance imaging showed a double-lumen inferior vena cava and a rod-like solid component attached to a sac-like lesion in the right heart chambers. Digital subtraction angiography showed an arteriovenous malformation draining to the inner lumen of the inferior vena cava. (orig.)

Effects of an RF limiter on TEXTOR's edge plasmas

International Nuclear Information System (INIS)

Boedo, J.A.; Sakawa, Y.; Gray, D.S.; Mank, G.; Noda, N.

1997-01-01

Studies directed towards the reduction of particle and heat fluxes to plasma facing components by the application of ponderomotive forces generated by radio frequency (RF) are being conducted in TEXTOR. A modified poloidal limiter is used as an antenna with up to 3 kW of RF power; the data obtained show that the plasma is repelled by the RF ponderomotive potential. The density is reduced by a factor of 2-4 and the radial decay length is substantially altered. The density near the limiter decays exponentially with RF power. The electron temperature profile changes, with the decay length becoming longer (almost flat) during the RF. The temperature in the scrape off layer (SOL) increases and its increase is roughly proportional to the RF power until it saturates, suggesting that the heating efficiency drops with power, and that improved performance is to be expected at higher powers. (orig.)

A self-adaptive feedforward rf control system for linacs

International Nuclear Information System (INIS)

Zhang Renshan; Ben-Zvi, I.; Xie Jialin

1993-01-01

The design and performance of a self-adaptive feedforward rf control system are reported. The system was built for the linac of the Accelerator Test Facility (ATF) at Brookhaven National Laboratory. Variables of time along the linac macropulse, such as field or phase are discretized and represented as vectors. Upon turn-on or after a large change in the operating-point, the control system acquires the response of the system to test signal vectors and generates a linearized system response matrix. During operation an error vector is generated by comparing the linac variable vectors and a target vector. The error vector is multiplied by the inverse of the system's matrix to generate a correction vector is added to an operating point vector. This control system can be used to control a klystron to produce flat rf amplitude and phase pulses, to control a rf cavity to reduce the rf field fluctuation, and to compensate the energy spread among bunches in a rf linac. Beam loading effects can be corrected and a programmed ramp can be produced. The performance of the control system has been evaluated on the control of a klystron's output as well as an rf cavity. Both amplitude and phase have been regulated simultaneously. In initial tests, the rf output from a klystron has been regulated to an amplitude fluctuation of less than ±0.3% and phase variation of less than ±0.6deg. The rf field of the ATF's photo-cathode microwave gun cavity has been regulated to ±5% in amplitude and simultaneously to ±1deg in phase. Regulating just the rf field amplitude in the rf gun cavity, we have achieved amplitude fluctuation of less than ±2%. (orig.)

Pulsed rf superconductivity program at SLAC

International Nuclear Information System (INIS)

Campisi, I.E.; Farkas, Z.D.

1984-08-01

Recent tests performed at SLAC on superconducting TM 010 caavities using short rf pulses (less than or equal to 2.5 μs) have established that at the cavity surface magnetic fields can be reached in the vicinity of the theoretical critical fields without an appreciable increase in average losses. Tests on niobium and lead cavities are reported. The pulse method seems to be best suited to study peak field properties of superconductors in the microwave band, without the limitations imposed by defects. The short pulses also seem to be more effective in decreasing the causes of field emission by rf processing. Applications of the pulsed rf superconductivity to high-gradient linear accelerators are also possible

Rf system considerations for a large hadron collider

International Nuclear Information System (INIS)

Raka, E.

1988-01-01

In this paper, we shall discuss how we arrive at a particular choice of voltage and frequency; the type of acceleration structure that would be suitable for obtaining the required voltage and resonant impedance; static beam loading including a simplified beam stability criterion involving the beam current and total rf system shunt impedance; the basic principle of rf phase and frequency control loops; and the effect of rf noise and its interaction with these loops. Finally, we shall consider the need for and design of rf systems to damp independently coherent oscillations of individual bunches or groups of bunches. 30 refs., 17 figs., 2 tabs

RF Energy Harvesting Peel-and-Stick Sensors

Energy Technology Data Exchange (ETDEWEB)

Lalau-Keraly, Christopher [PARC; Schwartz, David; Daniel, George; Lee, Joseph

2017-08-29

PARC, a Xerox Company, is developing a low-cost system of peel-and-stick wireless sensors that will enable widespread building environment sensor deployment with the potential to deliver up to 30% energy savings. The system is embodied by a set of RF hubs that provide power to the automatically located sensor nodes, and relays data wirelessly to the building management system (BMS). The sensor nodes are flexible electronic labels powered by rectified RF energy transmitted by a RF hub and can contain multiple printed and conventional sensors. The system design overcomes limitations in wireless sensors related to power delivery, lifetime, and cost by eliminating batteries and photovoltaic devices. The sensor localization is performed automatically by the inclusion of a programmable multidirectional antenna array in the RF hub. Comparison of signal strengths when the RF beam is swept allows for sensor localization, further reducing installation effort and enabling automatic recommissioning of sensors that have been relocated, overcoming a significant challenge in building operations. PARC has already demonstrated wireless power and temperature data transmission up to a distance of 20m with a duty cycle less than a minute between measurements, using power levels well within the FCC regulation limits in the 902-928 MHz ISM band. The sensor’s RF energy harvesting antenna dimensions was less than 5cmx9cm, demonstrating the possibility of small form factor for the sensor nodes.

Outage Analysis of Asymmetric RF-FSO Systems

KAUST Repository

Ansari, Imran Shafique; Abdallah, Mohamed M.; Alouini, Mohamed-Slim; Qaraqe, Khalid A.

2017-01-01

In this work, the outage performance analysis of a dual-hop transmission system composed of asymmetric radio frequency (RF) channels cascaded with free-space optical (FSO) links is presented. The RF links are modeled by the Rayleigh fading

Indoor Wireless RF Energy Transfer for Powering Wireless Sensors

Directory of Open Access Journals (Sweden)

H. Visser

2012-12-01

Full Text Available For powering wireless sensors in buildings, rechargeable batteries may be used. These batteries will be recharged remotely by dedicated RF sources. Far-field RF energy transport is known to suffer from path loss and therefore the RF power available on the rectifying antenna or rectenna will be very low. As a consequence, the RF-to-DC conversion efficiency of the rectenna will also be very low. By optimizing not only the subsystems of a rectenna but also taking the propagation channel into account and using the channel information for adapting the transmit antenna radiation pattern, the RF energy transport efficiency will be improved. The rectenna optimization, channel modeling and design of a transmit antenna are discussed.

Radiofrequency (RF) radiation measurement for diathermy machine

International Nuclear Information System (INIS)

Rozaimah Abdul Rahim; Roha Tukimin; Mohd Amirul Nizam; Ahmad Fadzli; Mohd Azizi

2010-01-01

Full-text: Diathermy machine is one of medical device that use widely in hospital and clinic. During the diathermy treatment, high radiofrequency (RF) currents (shortwave and microwave) are used to heat deep muscular tissues through electromagnetic energy to body tissues. The heat increases blood flow, relieve pain and speeding up recovery. The stray RF radiation from the machine can exposes to unintended tissue of the patient, to the operator (physical therapist) and also can cause electromagnetic interference (EMI) effect to medical devices around the machine. The main objective of this study is to establish a database of the RF radiation exposure levels experienced by the operator and patient during the treatments. RF radiation (electric and magnetic field) produced by the diathermy machines were measured using special RF survey meters. The finding of this study confirms that radiation levels on the surface and near the applicator of the diathermy machine much more elevated due to the much closer distance to the source and they exceeding the occupational and general public exposure limit. The results also shows the field strengths drop very significantly when the distance of measurement increase. (author)

Phase calibration strategies for synchrotron RF signals

Energy Technology Data Exchange (ETDEWEB)

Andreev, Aleksandr [TEMF, Technische Universitaet Darmstadt (Germany); Klingbeil, Harald [TEMF, Technische Universitaet Darmstadt (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Lens, Dieter [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany)

2016-07-01

For the FAIR facility that is currently under construction, the beam quality requirements impose several demands on the low-level RF (LLRF) systems. For example the phase error of the gap voltage of a specific RF cavity must be less than 1 . The RF reference signals for the FAIR synchrotron RF cavity systems are generated by direct digital synthesis modules (DDS) mounted in one crate called Group-DDS. In order to allow performing various multi-harmonic operations, each DDS unit operates at a certain mode defined by the harmonic number that can be changed during the operation. Since the DDS modules generate reference RF signals for different LLRF systems, the precise calibration of units to compensate the different phase response is of importance. The currently used calibration procedure is done with a fixed harmonic number for each module and uses the DDS module configured to the highest harmonic number as a reference. If the harmonic number of the DDS module is changed, one then has to repeat the calibration for the new values. Therefore, a new calibration method with respect to the absolute phases of DDS modules is under development and will be presented.

Low-level RF control system issues for an ADTT accelerator

International Nuclear Information System (INIS)

Ziomek, C.D.; Regan, A.H.; Lynch, M.T.; Bowling, P.S.

1994-01-01

The RF control system for a charged-particle accelerator must maintain the correct amplitude and phase of RF field inside the accelerator cavity in the presence of perturbations, noises, and time varying system components. For an accelerator with heavy beam-loading, fluctuations in the beam current cause large perturbations to the RF field amplitude and phase that must be corrected by the RF control system. The ADTT applications require a high-current, heavily beam-loaded, continuous-wave (CW) accelerator. Additional concerns created by the CW operation include system start-up, beam interruption, and fault recovery. Also, the RF control system for an ADTT facility must include sophisticated automation to reduce the operator interaction and support. This paper describes an RF control system design that addresses these various issues by evaluation a combination of feedback and feed forward control techniques. Experience from the high-current Ground Test Accelerator (GTA) is drawn upon for this RF control system design. Comprehensive computer modeling with the Matrix x software has been used to predict the performance of this RF control system

Design of RF system for CYCIAE-230 superconducting cyclotron

Energy Technology Data Exchange (ETDEWEB)

Yin, Zhiguo, E-mail: bitbearAT@hotmail.com; Ji, Bin; Fu, Xiaoliang; Cao, Xuelong; Zhao, Zhenlu; Zhang, Tinajue

2017-05-11

The CYCIAE230 is a low-current, compact superconducting cyclotron designed for proton therapy. The Radio Frequency system consists of four RF cavities and applies second harmonic to accelerate beams. The driving power for the cavity system is estimated to be approximately 150 kW. The LLRF controller is a self-made device developed and tested at low power using a small-scale cavity model. In this paper, the resonator systems of an S.C. cyclotron in history are reviewed. Contrary to those RF systems, the cavities of the CYCIAE230 cyclotron connect two opposite dees. Two high-power RF windows are included in the system. Each window carries approximately 75 kW RF power from the driver to the cavities. Thus, the RF system for the CY-CIAE230 cyclotron is operated in driven push–pull mode. The two-way amplifier-coupler-cavity systems are operated with approximately the same amount of RF power but 180° out of phase compared with each other. The design, as well as the technical advantage and limitations of this operating mode, of the CYCIAE230 cyclotron RF system is analyzed.

RF system considerations for large high-duty-factor linacs

International Nuclear Information System (INIS)

Lynch, M.T.; Ziomek, C.D.; Tallerico, P.J.; Regan, A.H.; Eaton, L.; Lawrence, G.

1994-01-01

RF systems are often a major cost item for linacs, but this is especially true for large high-duty-factor linacs (up to and including CW) such as the Accelerator for Production of Tritium (APT) or the Accelerator for Transmutation of nuclear Waste (ATW). In addition, the high energy and high average beam current of these machines (approximately 1 GeV, 100--200 mA) leads to a need for excellent control of the accelerating fields in order to minimize the possibility of beam loss in the accelerator and the resulting activation. This paper will address the key considerations and limitations in the design of the RF system. These considerations impact the design of both the high power RF components and the RF controls. As might be expected, the two concerns sometimes lead to conflicting design requirements. For example minimum RF operating costs lead to a desire for operation near saturation of the high power RF generators in order to maximize the operating efficiency. Optimal control of the RF fields leads to a desire for maximum overdrive capability in those same generators in order to respond quickly to disturbances of the accelerator fields

Design of RF system for CYCIAE-230 superconducting cyclotron

Science.gov (United States)

Yin, Zhiguo; Ji, Bin; Fu, Xiaoliang; Cao, Xuelong; Zhao, Zhenlu; Zhang, Tinajue

2017-05-01

The CYCIAE230 is a low-current, compact superconducting cyclotron designed for proton therapy. The Radio Frequency system consists of four RF cavities and applies second harmonic to accelerate beams. The driving power for the cavity system is estimated to be approximately 150 kW. The LLRF controller is a self-made device developed and tested at low power using a small-scale cavity model. In this paper, the resonator systems of an S.C. cyclotron in history are reviewed. Contrary to those RF systems, the cavities of the CYCIAE230 cyclotron connect two opposite dees. Two high-power RF windows are included in the system. Each window carries approximately 75 kW RF power from the driver to the cavities. Thus, the RF system for the CY-CIAE230 cyclotron is operated in driven push-pull mode. The two-way amplifier-coupler-cavity systems are operated with approximately the same amount of RF power but 180° out of phase compared with each other. The design, as well as the technical advantage and limitations of this operating mode, of the CYCIAE230 cyclotron RF system is analyzed.

Outcomes in a series of 103 retroperitoneal sarcomas.

Science.gov (United States)

Pierie, J-P E N; Betensky, R A; Choudry, U; Willett, C G; Souba, W W; Ott, M J

2006-12-01

To report the effect on outcome of selection in patients receiving intra-operative electron beam radiation (IOERT) and external beam radiation therapy (EBRT). One hundred and three patients treated for primary RS were studied. Median follow-up was 27 months. Clinical presentation, tumor characteristics, and treatment methods were analyzed to determine impact on survival and recurrence and if selection was occurring. Mean age was 55+/-17 years. Mean tumor size was 15+/-6cm and 88 were high-grade. Complete gross tumor resection (CR) occurred in 62 patients and improved survival vs. both debulking (p=0.0005) and biopsy (p<0.0001). The 5- and 10-year survival rates were 62% and 52% for those with CR vs. 29% and 20% after incomplete resection. Among the 62 CR patients, there was selection to receive additional EBRT+/-IOERT in patients with high-grade tumors (p=0.005) and/or microscopically positive margins (p=0.011). In these high-risk patients there was a trend for IOERT to further augment survival vs. EBRT alone and to increase the time to both local and distant recurrences (p=0.036). Complete gross resection is the primary form of curative treatment for retroperitoneal sarcomas. Selection led to patients with high-risk tumors receiving additional radiation therapy. There appears to be a beneficial effect of IOERT plus EBRT in these high-risk patients after complete tumor resection.

High power RF systems for the BNL ERL project

Energy Technology Data Exchange (ETDEWEB)

Zaltsman, A.; Lambiase, R.

2011-03-28

The Energy Recovery Linac (ERL) project, now under construction at Brookhaven National Laboratory, requires two high power RF systems. The first RF system is for the 703.75 MHz superconducting electron gun. The RF power from this system is used to drive nearly half an Ampere of beam current to 2 MeV. There is no provision to recover any of this energy so the minimum amplifier power is 1 MW. It consists of 1 MW CW klystron, transmitter and power supplies, 1 MW circulator, 1 MW dummy load and a two-way power splitter. The second RF system is for the 703.75 MHz superconducting cavity. The system accelerates the beam to 54.7 MeV and recovers this energy. It will provide up to 50 kW of CW RF power to the cavity. It consists of 50 kW transmitter, circulator, and dummy load. This paper describes the two high power RF systems and presents the test data for both.

The absolute age of SE-RF-6 (Ngamanie) and its relation to SE-RF-2 (Nenumbo) : two decorated lapita sites in the southeast Solomon Islands

International Nuclear Information System (INIS)

Green, R.C.; Jones, M.

2007-01-01

The relative age of SE-RF-6, SE-RF-2 and SE-SZ-8, three decorative phase Lapita sites in the Reef/Santa Cruz region of the Outer Easter Islands of Solomon Islands, has been the subject of dispute. A review of the evidence recovered from SE-RF-6 (Ngamanie), in conjunction with a Bayesian calibration model, supports the notion that it postdates the nearby site of SE-RF-2 (Nenumbo). We conclude that the SE-RF-6 represents an occupation of 50 to 100 years duration (compared with 50 or less for SE-RF-2), beginning some time in the interval 2470-2910 BP. (author). 22 refs., 4 figs., 3 tabs

RF MEMS: status of the industry and roadmaps

Science.gov (United States)

Bouchaud, Jeremie; Wicht, Henning

2005-01-01

Microsystems for Radio Frequency applications, known as RF MEMS, have entered the commercialization phase in 2003. Bulk Acoustic Wave filters are already produced in series and first commercial samples of switches are available. On the other hand, reliability and packaging problems are still a major hurdle especially for switches and tunable capacitors. Will RF MEMS hold their promise to be one of the future major businesses for MEMS? The presentation will give an overview on RF MEMS applications and market players. WTC will highlight technical challenges that still have to be solved to open mass markets such as mobile telephony and WLAN. WTC will also present applications of RF MEMS and opportunities in niche markets with high added value like military and space applications. WTC will provide a regional analysis and compare R&D focus and public funding situation in North America, Europe and Asia. Finally, WTC will present an updated product roadmap market forecast for RF MEMS devices for the 2004-2008 time period.

Theory, analysis and design of RF interferometric sensors

CERN Document Server

Nguyen, Cam

2012-01-01

Theory, Analysis and Design of RF Interferometric Sensors presents the theory, analysis and design of RF interferometric sensors. RF interferometric sensors are attractive for various sensing applications that require every fine resolution and accuracy as well as fast speed. The book also presents two millimeter-wave interferometric sensors realized using RF integrated circuits. The developed millimeter-wave homodyne sensor shows sub-millimeter resolution in the order of 0.05 mm without correction for the non-linear phase response of the sensor's quadrature mixer. The designed millimeter-wave double-channel homodyne sensor provides a resolution of only 0.01 mm, or 1/840th of the operating wavelength, and can inherently suppress the non-linearity of the sensor's quadrature mixer. The experimental results of displacement and velocity measurement are presented as a way to demonstrate the sensing ability of the RF interferometry and to illustrate its many possible applications in sensing. The book is succinct, ye...

RF Breakdown in Normal Conducting Single-cell Structures

CERN Document Server

Dolgashev, Valery A; Higo, Toshiyasu; Nantista, Christopher D; Tantawi, Sami G

2005-01-01

Operating accelerating gradient in normal conducting accelerating structures is often limited by rf breakdown. The limit depends on multiple parameters, including input rf power, rf circuit, cavity shape and material. Experimental and theoretical study of the effects of these parameters on the breakdown limit in full scale structures is difficult and costly. We use 11.4 GHz single-cell traveling wave and standing wave accelerating structures for experiments and modeling of rf breakdown behavior. These test structures are designed so that the electromagnetic fields in one cell mimic the fields in prototype multicell structures for the X-band linear collider. Fields elsewhere in the test structures are significantly lower than that of the single cell. The setup uses matched mode converters that launch the circular TM01 mode into short test structures. The test structures are connected to the mode launchers with vacuum rf flanges. This setup allows economic testing of different cell geometries, cell materials an...

Application to the conservation of RF tags in the radiation environment

International Nuclear Information System (INIS)

Teraura, Nobuyuki; Ito, Kunio; Takahashi, Naoki; Sakurai, Kouichi

2011-01-01

RF tags that are implemented RFID technology as tag has been used in various fields. Tags have been developed, such as resistance to chemicals and high temperature resistant RF tags are also used in specialized fields. The RF tag apply to the existing nuclear field, had been concerned about the effects of radiation to the RF tags. Now, since the RF tag with a goal to develop radiation-proof, we have examined, such as applying for maintenance of nuclear facilities under radiation environment. We report the results and RF tags to be radiation resistant. (author)

Retroperitoneal fibrosis: the clinical and radiological manifestation

International Nuclear Information System (INIS)

Pan Weidong; Zhao Rongguo; Qin Mingwei; Xue Huadan; Liang Jixiang

2005-01-01

Objective: To analyze the clinical and radiological features of retroperitoneal fibrosis (RPF), and to deepen the understanding of this unusual disease and improve the diagnostic level at the early stage. Methods: Fourteen cases (10 males and 4 females, mean age 45.8 years) of pathologically diagnosed RPF from January 1990 to June 2004 were summarized. The clinical and radiological performance of the cases were analyzed. All patients received non-contrast CT scanning, 10 of them underwent enhanced CT scanning as well. 8 patients received MRI, 10 patients received IVP examination, and 11 received B-ultrasound. Results: (1) The very first symptoms usually included back pain, bellyache (10 cases), or urinary tract obstruction (3 cases), with increase of ESR, IgG, CRP value and abnormal renal function. (2) The result of radiological examination showed that 11 lesions of the 14 cases located at retroperitoneum. Ten cases were mass type and 4 cases were diffuse type. Non-contrast CT scanning revealed soft tissue mass at retroperitoneum with in homogenous or homogenous density. After contrast medium injection the lesions were enhanced with different extent. MRI results showed that the lesions presented low signal in T 1 WI, while in T 2 WI the signals had no obvious coherence but were different from one case to another. Conclusion: Radiological examination is one of the important methods for diagnosis of RPF. Based on the different characteristics of RPF in CT and MRI, together with the clinical findings, we will get valuable references for staging and follow-up of RPF. (authors)

Plasma edge cooling during RF heating

International Nuclear Information System (INIS)

Suckewer, S.; Hawryluk, R.J.

1978-01-01

A new approach to prevent the influx of high-Z impurities into the core of a tokamak discharge by using RF power to modify the edge plasma temperature profile is presented. This concept is based on spectroscopic measurements on PLT during ohmic heating and ATC during RF heating. A one dimensional impurity transport model is used to interpret the ATC results

High-powered, solid-state rf systems

International Nuclear Information System (INIS)

Reid, D.W.

1987-01-01

Over the past two years, the requirement to supply megawatts of rf power for space-based applications at uhf and L-band frequencies has caused dramatic increases in silicon solid-state power capabilities in the frequency range from 10 to 3000 MHz. Radar and communications requirements have caused similar increases in gallium arsenide solid-state power capabilities in the frequency ranges from 3000 to 10,000 MHz. This paper reviews the present state of the art for solid-state rf amplifiers for frequencies from 10 to 10,000 MHz. Information regarding power levels, size, weight, and cost will be given. Technical specifications regarding phase and amplitude stability, efficiency, and system architecture will be discussed. Solid-stage rf amplifier susceptibility to radiation damage will also be examined

High RF Power Production for CLIC

CERN Document Server

Syratchev, I; Adli, E; Taborelli, M

2007-01-01

The CLIC Power Extraction and Transfer Structure (PETS) is a passive microwave device in which bunches of the drive beam interact with the impedance of the periodically loaded waveguide and excite preferentially the synchronous mode. The RF power produced (several hundred MW) is collected at the downstream end of the structure by means of the Power Extractor and delivered to the main linac structure. The PETS geometry is a result of multiple compromises between beam stability and main linac RF power needs. Another requirement is to provide local RF power termination in case of accelerating structure failure (ON/OFF capability). Surface electric and magnetic fields, power extraction method, HOM damping, ON/OFF capability and fabrication technology were all evaluated to provide a reliable design

Computational Tools for RF Structure Design

CERN Document Server

Jensen, E

2004-01-01

The Finite Differences Method and the Finite Element Method are the two principally employed numerical methods in modern RF field simulation programs. The basic ideas behind these methods are explained, with regard to available simulation programs. We then go through a list of characteristic parameters of RF structures, explaining how they can be calculated using these tools. With the help of these parameters, we introduce the frequency-domain and the time-domain calculations, leading to impedances and wake-fields, respectively. Subsequently, we present some readily available computer programs, which are in use for RF structure design, stressing their distinctive features and limitations. One final example benchmarks the precision of different codes for calculating the eigenfrequency and Q of a simple cavity resonator.

Prototype rf cavity for the HISTRAP accelerator

International Nuclear Information System (INIS)

Mosko, S.W.; Dowling, D.T.; Olsen, D.K.

1989-01-01

HISTRAP, a proposed synchrotron-cooling-storage ring designed to both accelerate and decelerate very highly charged very heavy ions for atomic physics research, requires an rf accelerating system to provide /+-/2.5 kV of peak accelerating voltage per turn while tuning through a 13.5:1 frequency range in a fraction of a second. A prototype half-wave, single gap rf cavity with biased ferrite tuning was built and tested over a continuous tuning range of 200 kHz through 2.7 MHz. Initial test results establish the feasibility of using ferrite tuning at the required rf power levels. The resonant system is located entirely outside of the accelerator's 15cm ID beam line vacuum enclosure except for a single rf window which serves as an accelerating gap. Physical separation of the cavity and the beam line permits in situ vacuum baking of the beam line at 300/degree/C