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1.
Am J Case Rep ; 23: e936964, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36184835

RESUMO

BACKGROUND Wandering spleen (WS) is a rare medical condition in which the spleen migrates from its usual position commonly to the pelvis or lower abdomen assuming an ever-wandering state. The incidence of ectopic spleen is 0.2%, with variable clinical manifestations from asymptomatic to abdominal emergency. Symptoms are most attributed to complications related to torsion, so that a nonoperative management of a WS is not advised. According to the literature, 69.5% of patients with WS need splenectomy and 78.6% need laparotomy. CASE REPORT The patient exhibited vague intermittent lower abdominal pain for 6 months due to progressive torsion of the spleen, which resulted in venous congestion. Abdominal investigation revealed a mobile intra-abdominal mass and parenchymatous consistency in the pelvis. Diagnosis by computed tomography outlined abdominal splenomegaly with abnormal position both of pancreas and stomach. Laparoscopy established a giant spleen, with a lengthened pelvic and twisty vascular pedicle. In its ectopic location, the spleen had dragged the pancreas with it, which had taken a vertical position. The classic splenic ligaments were not recognizable. Spleen was removed with median laparotomic incision. Splenectomy was performed to prevent any traumatic fractures of the spleen, a complete twist of the splenic hilum, and the onset of recurrent acute pancreatitis. CONCLUSIONS Wandering spleen is rare in patients presenting with acute abdominal pain. An approach supported by clinical findings and investigation, even considering splenectomy over splenopexy, and laparoscopy over open surgery, may solve and prevent complications and health risks.


Assuntos
Hérnia Hiatal , Hérnias Diafragmáticas Congênitas , Obstrução Intestinal , Laparoscopia , Pancreatite , Baço Flutuante , Dor Abdominal/etiologia , Doença Aguda , Feminino , Hérnia Hiatal/complicações , Hérnias Diafragmáticas Congênitas/cirurgia , Humanos , Obstrução Intestinal/etiologia , Obstrução Intestinal/cirurgia , Laparoscopia/métodos , Pancreatite/complicações , Pelve , Esplenectomia/efeitos adversos , Esplenomegalia/complicações , Esplenomegalia/cirurgia , Baço Flutuante/complicações , Baço Flutuante/cirurgia
2.
Phys Rev Lett ; 122(10): 107402, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30932659

RESUMO

We demonstrate amplification of longitudinal optical (LO) phonons by polar-optical interaction with an electron plasma in a GaAs structure coupled to a metallic metasurface using two-color two-dimensional spectroscopy. In a novel scheme, the metamaterial resonator enhances broadband terahertz fields, which generate coherent LO phonons and drive free electrons in the conduction band of GaAs. The time evolution of the LO phonon amplitude is monitored with midinfrared pulses via the LO-phonon-induced Kerr nonlinearity of the sample, showing an amplification of the LO phonon amplitude by up to a factor of 10, in agreement with a theoretical estimate.

3.
Opt Lett ; 42(15): 2918-2921, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28957207

RESUMO

A design is presented for a beam splitter suitable for ultrashort pulses in the mid-infrared and terahertz spectral range consisting of a structured metal layer on a diamond substrate. Both the theory and experiment show that this beam splitter does not distort the temporal pulse shape.

4.
Anticancer Res ; 36(12): 6579-6583, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27919986

RESUMO

AIM: The feasibility of videoscopic inguinal-iliac-obturator lymphadenectomy (VIIOL) was assessed in 20 patients with melanoma and compared with a retrospective sample of 24 patients undergoing standard 'open' technique (IIOL). RESULTS: No postoperative death occurred; the mean operative time was lower in the IIOL series (190 min vs. 302 min) but the quality of life was greatly improved in the VIIOL group thanks to earlier bladder catheter removal, no nasogastric suction, less pain, earlier mobilization, lower in-hospital stay, and earlier resumption of daily activities (27.6 vs. 83.2 days, p<0.001). Six out of 20 patients in the IIOL series had wound complications (30%) as compared to one in the VIIOL series (4%) (p=0.035). CONCLUSION: Staging and therapeutic efficacy of VIIOL were similar to the standard technique; the longer operative time of VIIOL was greatly compensated by less pain, lower wound complication rate, and earlier discharge from hospital and recovery of daily activities.


Assuntos
Ílio/cirurgia , Canal Inguinal/cirurgia , Excisão de Linfonodo/métodos , Melanoma/cirurgia , Feminino , Humanos , Metástase Linfática , Masculino , Melanoma/patologia , Pessoa de Meia-Idade
5.
J Chem Phys ; 144(18): 184202, 2016 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-27179477

RESUMO

We present the first two-dimensional (2D) terahertz (THz) experiment with three phase-locked THz pulses and a fully phase-resolved detection of the nonlinearly emitted field by electrooptic sampling. In a prototype experiment we study the ultrafast dynamics of nonlinear two-phonon and two-photon interband coherences in the narrow-gap semiconductor InSb. Due to the extraordinarily large optical interband dipole of InSb the experiments were performed in the strongly nonperturbative regime of light-matter interaction allowing for impulsive off-resonant excitation of both two-phonon coherences and two-photon interband coherences, the ultrafast dynamics of which is experimentally observed as a function of the waiting time in the three-pulse 2D experiment. Our novel three-pulse 2D THz spectroscopy paves the way for the detailed investigation of nonlinear quantum coherences in solids and holds potential for an extension to other systems.

6.
Phys Rev Lett ; 116(17): 177401, 2016 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-27176538

RESUMO

We report the first observation of two-phonon quantum coherences in a semiconductor. Two-dimensional terahertz (THz) spectra recorded with a sequence of three THz pulses display strong two-phonon signals, clearly distinguished from signals due to interband two-photon absorption and electron tunneling. The two-phonon coherences originate from impulsive off-resonant excitation in the nonperturbative regime of light-matter interaction. A theoretical analysis provides the relevant Liouville pathways, showing that nonlinear interactions using the large interband dipole moment generate stronger two-phonon excitations than linear interactions.

7.
Opt Lett ; 40(14): 3404-7, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26176480

RESUMO

Electric-field transients covering the extremely wide frequency range from 0.5 to 26 THz are generated in the organic nonlinear crystal 4-N,N-dimethylamino-4'-N'-methylstilbazolium 2,4,6-trimethylbenzenesulfonate (DSTMS). Parametric difference frequency mixing within the spectrum of 25-fs amplified pulses centered at 800 nm provides a highly stable broadband output with an electric-field amplitude of up to several hundred kilovolts/cm. The high stability of the terahertz pulse parameters allows for sensitive phase-resolved broadband spectroscopy of optically thick crystalline samples.

8.
Melanoma Res ; 19(4): 243-51, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19584766

RESUMO

We reviewed our experience to assess the predictive role of preoperative lymphoscintigraphy with regard to the pathological status of sentinel lymph node (sN) in patients with cutaneous melanoma, to optimize the surgical treatment planning with regard to the use of intraoperative frozen section examination of sN. Eighty-eight patients with clinically node-negative cutaneous melanoma pT1b-T4 stage underwent preoperative lymphoscintigraphy for the lymphatic mapping of sN. A lymphoscintigraphic 'score' (from L1 to L5) was developed based on the ratio of radiotracer concentration within sN nodes as compared with the injection site. Our score allowed us to foresee that sN of patients with thick melanomas (T3 and T4) and a low preoperative score (L1-L2-L3) had a 90% expected likelihood (P<0.001) of harboring metastasis, whereas sN in patients with thin melanomas (T1b-T2) and high preoperative score (from L4 to L5) showed a 100% likelihood of being metastasis free. In conclusion, the sN is a reliable predictor of regional lymph node status in patients with cutaneous malignant melanoma. Moreover, we suggest that a low score (L1-L2-L3) associated with a thick melanoma is a good predictive factor of the positive sN involvement. This information could be useful in scheduling the intraoperative frozen-section examination with an expected benefit of a positive test in almost 90% of patients. Such patients might be selected for a 'one-stage' procedure with a more effective cost/benefit ratio and decreased hospitalization costs.


Assuntos
Linfonodos/diagnóstico por imagem , Metástase Linfática/diagnóstico por imagem , Melanoma/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Cuidados Intraoperatórios , Excisão de Linfonodo , Linfonodos/fisiologia , Linfonodos/cirurgia , Metástase Linfática/diagnóstico , Masculino , Melanoma/patologia , Melanoma/secundário , Melanoma/cirurgia , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Cintilografia , Estudos Retrospectivos , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Agregado de Albumina Marcado com Tecnécio Tc 99m , Carga Tumoral
9.
Anticancer Res ; 27(4C): 2849-53, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17695459

RESUMO

BACKGROUND: Primary melanoma of the esophagus is a very rare and aggressive neoplasm; only a small number of patients survive more than 1 year after initial diagnosis. CASE REPORT: We describe a case of primary melanoma of the esophagus in a woman with a history of invasive breast cancer. The patient suffered from dysphagic and dyspeptic disorders. The abdomen ultrasonography and the esophagogastroscopy showed a lesion located at the esophago-gastric junction extending to the gastric fundus. Histological and immunohistochemical studies revealed a primary esophageal infiltrating melanoma. A total gastrectomy and regional lymphadenectomy with a partial resection of the distal esophagus was performed. RESULTS: During laparotomic exploration, numerous dark lymp hnodes were found. On frozen sections, surprisingly neither malignant cells nor melanin were detected in the lymph nodes. Resection margins were not involved with the tumor. CONCLUSION: Patient is still alive with no evidence of recurrence at 24 months after surgical treatment, alone.


Assuntos
Neoplasias da Mama/patologia , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Linfonodos/patologia , Melanoma/patologia , Melanoma/cirurgia , Idoso , Feminino , Humanos , Excisão de Linfonodo , Linfonodos/cirurgia , Metástase Linfática
10.
Anticancer Res ; 27(3B): 1605-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17595783

RESUMO

Primary osteosarcoma of the spermatic cord is a rare tumour with few mentions in the literature. A 59-year-old man presented with a large painless left inguinal and scrotal mass. The patient underwent excision of the mass, which arose from the spermatic cord. A left high dissection of the spermatic cord and radical orchiectomy due to associated atrophy of the left testicle were performed. Pathological findings were suggestive of spermatic cord osteosarcoma. The patient died eleven years later of metastatic lung disease. Spermatic cord osteosarcoma is an uncommon neoplasm and its preoperative diagnosis is very difficult. Any palpable suspicious mass of the cord should be investigated with ultrasonography before excision; CT scan and magnetic resonance imaging may be helpful in defining preoperative diagnosis and the extension of the mass into the neighbouring tissues. Surgical treatment of spermatic cord sarcomas in adults is via a radical orchiectomy with high dissection of the spermatic cord and en bloc excision of involved neighbouring tissues; overall 5- and 10-year survival rates are reported in the literature to be 75% and 55%, respectively.


Assuntos
Neoplasias Ósseas/patologia , Osteossarcoma/patologia , Cordão Espermático/patologia , Neoplasias Testiculares/patologia , Neoplasias Ósseas/cirurgia , Evolução Fatal , Humanos , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Orquiectomia , Osteossarcoma/cirurgia , Cordão Espermático/cirurgia , Neoplasias Testiculares/cirurgia
11.
J Surg Oncol ; 85(3): 102-11, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14991881

RESUMO

BACKGROUND AND OBJECTIVES: Literature review suggests that the sentinel lymph node (sN) represents a reliable predictor of axillary lymph node status in breast cancer patients; however, some important issues, such as the optimisation of the technique for the intraoperative identification of the sN, the role of intraoperative frozen section examination of the sN, and the clinical implications of sN metastasis as regards the surgical management of the axilla, still require further confirmation. The authors aimed (1) to assess the feasibility of sN identification with a combined approach (vital blue dye lymphatic mapping and radioguided surgery, RGS) and the specific contribution of either techniques to the detection of the sN, (2) to determine the accuracy and usefulness of intraoperative frozen section examination of the sN in order to perform a one-stage surgical procedure, and (3) to define how the sN might modulate the therapeutic planning in different stages of disease. MATERIALS AND METHODS: From October 1997 to June 2001, 334 patients with early-stage (T(1-2) N(0) M(0)) invasive mammary carcinoma underwent sN biopsy; the average age of patients was 61.5 years (range, 39-75 years). In a subset of 153 patients, both vital blue dye (Patent Blue-V) lymphatic mapping and RGS were used to identify the sN, and the relative contribution of each of the two techniques was assessed. RESULTS: In the whole group, the sN was identified in 326 of 334 patients (97.6%), and 105 of 326 patients (37.3%) had positive axillary lymph nodes (pN+). In 9 of 105 pN+ patients, the definitive histologic examination of the sN did not show metastases but these were detected in non-sN, thus giving an 8.6% false-negative rate, a negative predictive value of 94.5% (156/165), and an accuracy of 96.5% (252/261). As regards the specific contribution of the two different techniques used in the identification of the sN, the detection rate was 73.8% (113/153) with Patent Blue-V alone, 94.1% (144/153) with RGS alone, and 98.7% (151/153) with Patent Blue-V combined with RGS (P < 0.001). Noteworthy, whenever the sN was identified, the prediction of axillary lymph node status was remarkably similar (93-95% sensitivity; 100% specificity; 95-97% negative predictive value, and 97-98% accuracy) whichever of the three procedures was adopted (Patent Blue-V alone, RGS alone, or combined Patent Blue-V and RGS). Intraoperative frozen section examination was performed in 261 patients, who had at least one sN identified, out of 267 patients who underwent complete axillary dissection; 170 patients had histologically negative sN (i.o. sN-) and 91 patients histologically positive sN (i.o. sN+). All 91 i.o. sN+ were confirmed by definitive histology, whereas in 14 of 170 i.o. sN- patients (8.2%) metastases were detected at definitive histology. As regards the correlation between the size of sN metastasis, the primary tumour size, and the status of non-sN in the axilla, micrometastases were detected at final histology in 23 patients and macrometastases in 82 patients. When only micrometastases were detected, the sN was the exclusive site of nodal metastasis in 20 of 23 patients (86.9%) while in 3 patients with tumour size larger than 10 mm micrometastases were detected also in non-sN. Macrometastases were never detected in pT(1a) breast cancer patients; the sN was the exclusive site of these metastases in 30 patients (36.6%), while in 52 patients (63.4%) there were metastases both in sN and non-sN. CONCLUSIONS: Sentinel lymphadenectomy can better be accomplished when both procedures (lymphatic mapping with vital blue dye and RGS) are used, because of the significantly higher sN detection rate, although the prediction of axillary lymph node status remains remarkably similar whichever method is used. The intraoperative frozen section examination proved to be rather accurate in predicting the actual pathologic status of the sN, with a negative predictive value of 91.8%; in 35% of patients it allowed sN biopsy and axillary dissection to be performed in a one-stage surgical procedure. Finally, specific clinical and histopathologic features of the primary tumour and sN might be used to tailor the loco-regional and systemic treatment in different clinical settings, such as in ductal carcinoma in-situ (DCIS), early-stage invasive breast cancer, and patients with large breast cancer undergoing neo-adjuvant CT for breast-saving surgery as well as elderly patients with operable breast cancer.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Excisão de Linfonodo , Linfonodos/patologia , Biópsia de Linfonodo Sentinela , Adulto , Idoso , Axila/cirurgia , Protocolos Clínicos/normas , Feminino , Secções Congeladas , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Sensibilidade e Especificidade
12.
J Surg Oncol ; 85(3): 133-40, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14991885

RESUMO

BACKGROUND: The sentinel lymph node (sN) represents one of the most powerful predictors of the outcome of patients with Stages I and II cutaneous melanoma, and may be relevant for the therapeutic planning of early-stage melanoma patients. Since adopting the technique of lymphatic mapping with vital blue dye (Patent Blue-V) in July 1993, we have periodically up-dated the methodology and revised our results in order to define the contribution of radio-guided surgery (RGS) to the detection of the sN as well as the role of intraoperative frozen section examination of the sN. MATERIALS AND METHODS: Between July 1993 and December 1997, 180 patients with clinically node-negative primary cutaneous melanoma (Stages I-II) underwent sN biopsy followed by "selective lymph node dissection" (SLND) whenever sN metastasis was detected. Presently, complete data are available in 165 patients who were divided into two consecutive subsets of 39 and 126 patients, based on the technique for the identification of the sN: Patent Blue-V only or Patent Blue-V associated to RGS. Moreover, in this second subset of patients intraoperative frozen section findings were compared with definitive pathologic examination. RESULTS: As regards the first subset of 39 patients (17 males and 22 females; mean age 51.3 years), the sN was identified in 35 patients (89.7%); 8 patients (22.8%) were found to have metastatic melanoma cells in their sN, and they all underwent SLND of the affected basin. As regards the second set of 126 patients (54 males and 72 females; mean age 53.5 years), the sN was detected in every case by means of the combined technique (Patent Blue-V and RGS): in 4 of 126 patients (3.2%), the sN was detected by means of RGS only whereas in no patient was the sN detected by Patent Blue-V only. Frozen section examination was performed in 123 of 126 patients who had sN detection by Patent Blue-V and RGS, and the intraoperative examination had a sensitivity of 66.6% (22 of 33), specificity of 100% (90 of 90), negative predictive value of 89.1% (90 of 101), and accuracy of 91% (112 of 123). The benefit of frozen section examination in avoiding a two-stage procedure was 17.9% (22 of 123 patients). In patients with thicker lesions (pT(3)-pT(4)), the sensitivity and the benefit of intraoperative examination were 76% (19 of 25) and 32% (19 of 59 patients), respectively. CONCLUSIONS: Sentinel node lymphadenectomy can be better accomplished when both procedures (lymphatic mapping with Patent Blue-V and RGS) are used because the two methods look quite complementary. In fact, the use of the radiocolloid mapping allows to detect a hot spot in the regional basin prior to making the skin incision in order to perform a minimal invasive access, and it may also more accurately differentiate the true sN from a secondary echelon node (non-sN). The use of frozen section examination should be restricted to patients with pT(3)-pT(4) primary melanoma, due to the higher sensitivity and benefit in terms of avoiding a two-stage operative procedure.


Assuntos
Linfonodos/patologia , Melanoma/patologia , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Período Intraoperatório , Masculino , Melanoma/cirurgia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Sensibilidade e Especificidade , Neoplasias Cutâneas/cirurgia
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