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This paper deals with the control of wind energy systems with the doubly fed induction generator (DFIG) without recurring to any mechanical sensors. The control objective dressed here is twofold: maximum power point tracking (MPPT) and reactive power regulation in the DFIG. The designed controller is based on the nonlinear state-space representation of the controlled system, including a sliding mode controller and a high gain observer. The whole system enjoys a semi-global practical stability, proved using tools from the Lyapunov theory. These theoretical results are confirmed by simulations involving wide range variation of the wind speed.

The problem of Maximum Power Point Tracking (MPPT) for photovoltaic (PV) arrays is addressed. The considered PV System includes a PV Generator (PVG) connected to DC Bus using a DC/DC Converter. Unlike standard PV systems, the used static converter is of the series resonant type (SRC). Indeed, this latter optimizes the power losses during the switching phases. The proposed output feedback control is a robust nonlinear controller, based on Nonlinear model of PV System, ought to be able to instantaneously determine the maximum power point (MPP) when solar irradiance and temperature are measurable. It is formally shown that the developed controller actually meets the MPPT objective. These theoretical results are confirmed by simulation.

Background/Aims: Technological advancements had a serious impact on the evolution of robotic systems in stereotactic neurosurgery over the last three decades and may turn robot-assisted stereotactic neurosurgery into a sophisticated alternative to purely mechanical guiding devices. Objectives: To compare robot-assisted and conventional frame-based deep brain stimulation (DBS) surgery with regard to accuracy, precision, reliability, duration of surgery, intraoperative imaging quality, safety and maintenance using a standardized setup. Methods: Retrospective evaluation of 80 consecutive patients was performed who underwent DBS surgery using either a frame-based mechanical stereotactic guiding device (n = 40) or a stereotactic robot (ROSA Brain, MedTech, Montpellier, France) (n = 40). Results: The mean accuracy of robot-assisted and conventional lead implantation was 0.76 mm (SD: 0.37 mm, range: 0.17–1.52 mm) and 1.11 mm (SD: 0.59 mm, range: 0.10–2.90 mm), respectively. We observed a statistically significant difference in accuracy (p < 0.001) when comparing lateral deviations between both modalities. Furthermore, a statistical significance was observed when investigating the proportion of values exceeding 2.00 mm between both groups (p = 0.013). In 8.75% (n = 7) of conventionally implanted leads, lateral deviations were greater than 2.0 mm. With a maximum value of 1.52 mm, this threshold was never reached during robot-guided DBS. The mean duration of DBS surgery could be reduced significantly (p < 0.001) when comparing robot-guided DBS (mean: 325.1 ± 81.6 min) to conventional lead implantation (mean: 394.8 ± 66.6 min). Conclusions: Robot-assisted DBS was shown to be superior to conventional lead implantation with respect to accuracy, precision and operation time. Improved quality control, continuous intraoperative monitoring and less manual adjustment likely contribute to the robotic system’s reliability allowing high accuracy during lead implantation despite limited experience. Hence, robot-assisted lead implantation can be considered an appropriate and reliable alternative to purely mechanical devices.

La fibrose retroperitoneale (FRP) est une maladie rare. Elle se caracterise par la transformation progressive du tissu adipeux retoperitoneal en une masse fibreuse qui enserre l'aorte, la veine cave inferieure et les voies urinaires responsable d'une alteration progressive de la fonction renale. Le mode habituel de presentation de cette maladie comporte l'association de douleurs lombaires, d'une insuffisance renale, et d'un syndrome inflammatoire biologique. Nous rapportons 12 cas de fibrose retroperitoneale dont nous precisons les particularites cliniques, radiologiques et therapeutiques. Il s'agit d'une etude retrospective portant sur douze cas de fibrose retroperitoneale colliges au service d'urologie au CHU Hassan II de Fes durant une periode de 9 ans (2005-2013). Il s'agissait de dix hommes et deux femmes. La symptomatologie clinique etait tres variable, dominee par la douleur lombaire qui etait presente chez tous les malades et une hydrocele chez un patient. Les explorations biologiques avaient montre une insuffisance renale chez tous les malades et un syndrome inflammatoire chez dix patients. Le diagnostic de la maladie etait suspecte dans tous les cas sur les donnees de l'echographie qui a montre une obstruction de la voie excretrice superieure sans obstacle visible chez tous les malades, et confirme par la TDM abdominale sans injection du produit de contraste qui objectivait une lesion tissulaire retroperitoneale engainant les vaisseaux et les voies urinaires. Dans notre serie, la fibrose retroperitoneale etait idiopathique dans neuf cas. Elle etait peri anevrysmale chez deux malades, et post radiotherapie chez un malade. Tous nos patients avaient beneficie d'un drainage urinaire par sonde ureterale double J. Sept malades avaient recu une corticotherapie. Une amelioration clinique et biologique, avec disparition de la douleur et amelioration de l'etat general, a ete observee chez 6 patients. A travers cette etude nous avons confirme la rarete de la fibrose retroperitoneale, la difficulte de son diagnostic, la frequence de la douleur, du syndrome inflammatoire et de l'insuffisance renale. La TDM abdominale sans injection du produit de contraste confirme le diagnostic. Le drainage urinaire est indispensable dans la plupart des cas et le suivi regulier des malades est necessaire. Mots cles: Fibrose retroperitoneale, insuffisance renale, TDM abdominale, sondes ureterales en double j, corticotherapie English Title: Retroperitoneal fibrosis: about 12 cases English Abstract Retroperitoneal fibrosis (RPF) is rare. It is characterized by the gradual transformation of retroperitoneal adipose tissue into a fibrous mass surrounding the aorta, the inferior vena cava and the urinary tract responsible for progressive alteration in the renal function. It usually manifests as lumbar pain associated with renal failure and biologic inflammatory syndrome. We report 12 cases of retroperitoneal fibrosis in order to determine its clinical, radiological and therapeutic features. We conducted a retrospective study of 12 patients with retroperitoneal fibrosis whose medical data were collected in the Departement of Urology at the University Hospital Hassan II, Fes over a period of 9 years (2005-2013). The study involved ten men and two women. Clinical symptomatology was very variable, dominated by lumbar pain in all patients and hydrocele in 1 patient. Laboratory tests showed renal failure in all patients and inflammatory syndrome in 10 patients. The diagnosis of retroperitoneal fibrosis was suspected in all patients on ultrasound showing obstruction of the upper urinary tract without visible obstacle. The diagnosis was confirmed by abdominal CT scan without contrast that objectified a retroperitoneal tissue lesion enveloping the vessels and the urinary tract. Nine patients had idiopathic retroperitoneal fibrosis. Two patients had perianeurysmal fibrosis and one patient had post-radiation fibrosis. All patients underwent urinary drainage by double J. ureteral catheter. Seven patients underwent corticosteroid therapy. Six patients had an improvement of clinical and laboratory test outcome with disappearance of pain and improvement of the general condition. This study confirms the rarity of retroperitoneal fibrosis, the difficulty of diagnosis, pain associated with inflammatory syndrome and renal failure as common manifestations. Abdominal CT scan without contrast is the gold standard for definitive diagnosis. Urinary drainage is essential in most cases as well as regular monitoring of patients. Keywords: Retroperitoneal fibrosis, renal failure, abdominal computed tomography scan, double-J ureteral catheter, corticosteroid therapy

The increasing use of nonlinear loads entails serious electrical energy quality problem in power grids. In this paper, the energy quality issue is dealt with by using three-phase four-leg shunt active power filters (SAPFs). A new model that describes the whole controlled system including the SAPF and associated nonlinear and unbalanced loads is developed. The model also accounts for the electrical grid line impedance. The control objective is threefold: to make up for the harmonics and the reactive currents absorbed by the loads; to cancel the neutral current; and to regulate the inverter DC capacitor voltage. Based on the new model, a nonlinear controller is designed, using the backstepping technique. Moreover, the controller is made adaptive for compensating the uncertainty on the switching loss power. The performances of the proposed adaptive controller are formally analysed using tools from the Lyapunov stability and averaging theory, and their supremacy with respect to standard control solutions is illustrated through simulation.

Zirconocene catalyst supported on silica gel was prepared for olefin polymerization by surface modification of calcined silica with SiCl 4 , and the reaction between the modified silica and cyclopentadienyl sodium and ZrCl 4 . The catalyst was characterized by using Fourier-transform infrared (FT-IR) spectrometer, thermogravimetric (TG), and differential scanning calorimetric (DSC) analytic spectrometer. It was found that the metallocene structure could be formed and connected on silica surface by chemical bond. Initial catalytic tests showed that the supported metallocene was catalytically active (methylaluminoxane as a cocatalyst), producing polymer with higher molecular weight than the metallocene just immobilized on the surface of silica gel.

We evaluated the treatment of oligodendroglial brain tumors with interstitial brachytherapy (IBT) using (125)iodine seeds ((125)I) and analyzed prognostic factors.Between January 1991 and December 2010, 63 patients (median age 43.3 years, range 20.8-63.4 years) suffering from oligodendroglial brain tumors were treated with (125)I IBT either as primary, adjuvantly after incomplete resection, or as salvage therapy after tumor recurrence. Possible prognostic factors influencing disease progression and survival were retrospectively investigated.The actuarial 2-, 5-, and 10-year overall and progression-free survival rates after IBT for WHO II tumors were 96.9, 96.9, 89.8 % and 96.9, 93.8, 47.3 %; for WHO III tumors 90.3, 77, 54.9 % and 80.6, 58.4, 45.9 %, respectively. Magnetic resonance imaging demonstrated complete remission in 2 patients, partial remission in 13 patients, stable disease in 17 patients and tumor progression in 31 patients. Median time to progression for WHO II tumors was 87.6 months and for WHO III tumors 27.8 months. Neurological status improved in 10 patients and remained stable in 20 patients, while 9 patients deteriorated. There was no treatment-related mortality. Treatment-related morbidity was transient in 11 patients. WHO II, KPS ≥ 90 %, frontal location, and tumor surface dose 50 Gy were associated with increased overall survival (p ≤ 0.05). Oligodendroglioma and frontal location were associated with a prolonged progression-free survival (p ≤ 0.05).Our study indicates that IBT achieves local control rates comparable to surgery and radio-/chemotherapy treatment, is minimally invasive, and safe. Due to the low rate of side effects, IBT may represent an attractive option as part of a multimodal treatment schedule, being supplementary to microsurgery or as a salvage therapy after chemotherapy and conventional irradiation.

The efficacy and safety of stereotactic radiosurgery (SRS) for treatment of intracranial meningiomas has been demonstrated in numerous studies with short- and intermediate-term follow-up. In this retrospective single-center study, we present long-term outcomes of SRS performed with a linear accelerator (LINAC) for typical intracranial meningiomas. Between August 1990 and December 2007, 148 patients with 168 typical intracranial meningiomas were treated with stereotactic LINAC-SRS, either as primary treatment or after microsurgical resection. A median tumor surface dose of 12 Gy (range 7–20 Gy) and a median maximum dose of 24.1 Gy (range 11.3–58.6 Gy) was applied. The median target volume was 4.7 ml (range 0.2–32.8 ml, SD ± 4.8 ml). Overall mean radiological follow-up was 12.6 years. Tumor shrinkage was seen in 75 (44.6 %) and stable disease in 85 (50.6 %) cases. Eight of 168 meningiomas (4.8 %) showed local tumor progression. The tumor control rate (TCR) after 5, 10, and 15 years was 93.6 % at each time point, and the progression-free survival (PSF) rates were 92, 89, and 89 %, respectively. The neurological symptoms existing prior to LINAC-SRS improved in 77 patients (59.7 %), remained unchanged in 42 (32.6 %), and deteriorated in 10 (7.8 %) patients. Our study emphasizes the efficacy of LINAC-SRS for de novo, residual and recurrent typical intracranial meningiomas. A high long-term local TCR with a low morbidity rate could be achieved. LINAC-SRS should thus be considered as a primary treatment option, as one arm of a combined treatment approach for incompletely resected meningiomas, or as a salvage therapy for recurrences.

The current rationale for target selection in Tourette syndrome revolves around the notion of cortico-basal ganglia circuit involvement in the pathophysiology of the disease. However, despite extensive research, the ideal target for deep brain stimulation is still under debate, with many structures being neglected and underexplored. Based on clinical observations and taking into account the prevailing hypotheses of network processing in Tourette syndrome, we chose the fields of Forel, namely field H1, as a target for deep brain stimulation. The fields of Forel constitute the main link between the striatopallidal system and the thalamocortical network, relaying pallidothalamic projections from core anatomical structures to the thalamic ventral nuclear group. In a retrospective study we investigated two patients suffering from chronic, medically intractable Tourette syndrome who underwent bilateral lead implantation in field H1 of Forel. Clinical scales revealed significant alleviation of tics and comorbid symptoms, namely depression and anxiety, in the postoperative course in both patients.

Objective This study evaluates the efficacy of linear accelerator (LINAC) radiosurgery using micro multi-leaf collimator technique (μMLC) in the treatment of a consecutive series of patients with vestibular schwannomas. Patients and methods In this retrospective study, we enrolled 50 patients with non-neurofibromatosis type 2 vestibular schwannoma who were treated with μMLC LINAC-based SRS at University Hospital of Cologne, Germany. A minimum clinical follow-up of 24 months was conducted. Thirty-nine out of the 50 tumors (78 %) were treated with μMLC LINAC as a primary treatment (a newly diagnosed tumor). The remaining 11 vestibular schwannomas (22%) were treated as a salvage treatment (5 patients with a residual tumor; and 6 patients with a recurrent tumor following a microsurgical resection). The median tumor volume was 1.4 ml . The median tumor surface dose, median maximal dose and median therapeutic isodose were 12 Gy, 16 Gy and 77% respectively. Results Follow-up MR images showed that a tumor progression-free status was achieved for 95.7% of patients. Partial tumor shrinkage was observed after μMLC LINAC SRS for 21.3% of patients. No change in tumor size (a stable tumor) was noted for 74.5% of patients. Tumor progression was observed for 4.3% of patients. At the end of follow-up, the actuarial 5- year and 10 year progression-free survival after radiosurgery were both 95.7%. Conclusions LINAC radiosurgery using a micro multi-leaf collimator for vestibular schwannomas smaller than 3 cm is effective in yielding a high local tumor control, whereas the treatment-related morbidity remains low.

Intraoperative assessment of lead localization has become a standard procedure during deep brain stimulation surgery in many centers, allowing immediate verification of targeting accuracy and, if necessary, adjustment of the trajectory. The most suitable imaging modality to determine lead positioning, however, remains controversially discussed. Current approaches entail the implementation of computed tomography and magnetic resonance imaging. In the present study, we adopted the technique of intensity-based 2D 3D registration that is commonly employed in stereotactic radiotherapy and spinal surgery. For this purpose, intraoperatively acquired 2D x-ray images were fused with preoperative 3D computed tomography (CT) data to verify lead placement during stereotactic robot assisted surgery. Accuracy of lead localization determined from 2D 3D registration was compared to conventional 3D 3D registration in a subsequent patient study. The mean Euclidian distance of lead coordinates estimated from intensity-based 2D 3D registration versus flat-panel detector CT 3D 3D registration was 0.7 mm ± 0.2 mm. Maximum values of these distances amounted to 1.2 mm. To further investigate 2D 3D registration a simulation study was conducted, challenging two observers to visually assess artificially generated 2D 3D registration errors. 95% of deviation simulations, which were visually assessed as sufficient, had a registration error below 0.7 mm. In conclusion, 2D 3D intensity-based registration revealed high accuracy and reliability during robot guided stereotactic neurosurgery and holds great potential as a low dose, cost effective means for intraoperative lead localization.

This study evaluates the efficacy of linear accelerator (LINAC) radiosurgery using micro multi-leaf collimator technique (μMLC) in the treatment of a consecutive series of patients with vestibular schwannomas.In this retrospective study, we enrolled 50 patients with non-neurofibromatosis type 2 vestibular schwannoma who were treated with μMLC LINAC-based SRS at University Hospital of Cologne, Germany. A minimum clinical follow-up of 24 months was conducted. Thirty-nine out of the 50 tumors (78 %) were treated with μMLC LINAC as a primary treatment (a newly diagnosed tumor). The remaining 11 vestibular schwannomas (22%) were treated as a salvage treatment (5 patients with a residual tumor; and 6 patients with a recurrent tumor following a microsurgical resection). The median tumor volume was 1.4 ml. The median tumor surface dose, median maximal dose and median therapeutic isodose were 12 Gy, 16 Gy and 77% respectively.Follow-up MR images showed that a tumor progression-free status was achieved for 95.7% of patients. Partial tumor shrinkage was observed after μMLC LINAC SRS for 21.3% of patients. No change in tumor size (a stable tumor) was noted for 74.5% of patients. Tumor progression was observed for 4.3% of patients. At the end of follow-up, the actuarial 5- year and 10 year progression-free survival after radiosurgery were both 95.7%.LINAC radiosurgery using a micro multi-leaf collimator for vestibular schwannomas smaller than 3 cm is effective in yielding a high local tumor control, whereas the treatment-related morbidity remains low.

IntroductionPallidal deep brain stimulation (GPi-DBS) is an effective therapy for isolated dystonia, but 10–20% of patients show improvement below 25–30%. We here investigated causes of insufficient response to GPi-DBS in isolated dystonia in a cross-sectional study.MethodsPatients with isolated dystonia at time of surgery, and

L'angiomyolipome rénal est une tumeur qui est reconnue bénigne. Elle présente trois composantes différentes: musculaire, vasculaire et graisseuse, dont la distribution est variable. Le diagnostic repose sur la mise en évidence de la composante graisseuse intra-tumorale en TDM ou IRM. Exceptionnellement la tumeur peut avoir un caractère agressive avec extension locorégionale et veineuse (la veine rénale et la veine cave inferieure). Nous présentons une observation d'une patiente âgée de 37 ans présentant un Angiomyolipome rénal volumineux avec extension à la veine rénale.Mots clés: Rein, angiomyolipome, tumeur, veine rénaleEnglish Title: Aggressive renal angiomyolipoma extending to the renal vein: about a case and literature reviewEnglish AbstractRenal angiomyolipoma is a benign tumor. It is characterized of three different components: muscular, vascular and greasy. Their distribution is variable. Diagnosis is based on the identification of the intratumoral greasy component on CT scan and MRI. In exceptional circumstances, this tumor may be aggressive with locoregional and venous extension (renal vein and inferior vena cava). We here report the case of a 37-year old patient with voluminous renal angiomyolipoma extending to the renal vein.Keywords: Rein, angiomyolipoma, tumor, renal vein

A hierarchical porous zirconium phosphate membrane was prepared from bis(hexamethylenetriaminepenta(methylenephosphonic acid)), ZrOCl 2 ·8H 2 O, SiF 4 and hexadecyl trimethyl ammonium bromide. The membrane contains macropores of 200 nm in diameter, and mesopores of 19.2 nm in diameter. The membranes pores were bridged and limited by (–Si–O–) n edges. The porous membrane exhibited high efficiency in removing Pb 2+ and Cu 2+ from wastewater.

Background Pallidal deep brain stimulation (GPi-DBS) effectively ameliorates idiopathic dystonia, although approximately 15% of patients respond insufficiently. Although various thalamic and subthalamic targets have been suggested for dystonic tremor, no systematic studies have been published on thalamic DBS in dystonic tremor. We assessed the effect of thalamic/subthalamic area DBS (Th-DBS) on dystonic head tremor and dystonia in a single-blind design. Methods Dystonic head tremor and dystonia before and 3 months after surgery were quantified via blinded video-ratings using the Fahn-Tolosa-Marin-Tremor-Scale and the Burke-Fahn-Marsden-Dystonia-Rating-Scale in seven patients with idiopathic cervical or segmental dystonia, dystonic head tremor, and bilateral Th-DBS. Pain, side effects, adverse events, and stimulation parameters were assessed. Results Th-DBS improved dystonic tremor and dystonia (P

Background: The spinothalamocortical tract (STC) is seen as a neural tract responsible for or involved in the generation or transmission of thalamic pain. Either the thalamus itself or the posterior limb of the internal capsule (PLIC) are targets for deep brain stimulation (DBS) in patients with thalamic pain, but due to its low contrast, conventional MRI cannot visualize the STC directly. Objectives: To show the feasibility of integrating diffusion tensor imaging-based tractography into the stereotactic treatment planning for identification of an object-oriented lead trajectory that allows STC-DBS with multiple electrode contacts. Methods: Diffusion tensor imaging was performed in 4 patients with thalamic pain. The STC was modeled and integrated into the stereotactic treatment planning for DBS. DBS-lead implantation was done according to trajectory planning along the modeled STC at the level of the PLIC. Results: After implantation, electrode stimulation was possible over a length of more than 20 mm with a tractography-based trajectory along the PLIC part of the STC. After a follow-up of 12 months, pain relief of more than 40% was achieved in 3 of 4 patients with rating on a visual analogue scale. In 1 patient, stimulation failed to reach any long-lasting positive effects. Conclusions: Integrating tractography data into stereotactic planning of DBS in thalamic pain is technically feasible. It can be used to identify a lead trajectory that allows for multiple contact stimulation along the STC at the level of the PLIC. Due to long-lasting positive stimulation effect, tractography-guided stimulation of sensory fibers seems to be beneficial for thalamic pain relief.

This paper addresses the problem of controlling quarter-vehicle semi-active suspension systems. Presently, the suspension system involves a magnetorheologic MR damper featuring a hysteretic behavior captured through Dahl model. The control problem is dealt with backstepping control design. First, an observer is designed to get online estimates of the hysteresis internal state. Then, an adaptive state-feedback controller, that ensures a tight regulation of the chassis vertical position, is designed assuming all internal state variables to be accessible to measurements. Finally, an adaptive output-feedback controller is obtained combining the previous designed observer and state-feedback controller. It is formally established that the output-feedback controller asymptotically meets its control objectives. This theoretical result is confirmed by several simulation tests.

Genitourinary tuberculosis is a common type of extra-pulmonary tuberculosis . The kidneys, ureter, bladder or genital organs are usually involved. Tuberculosis of the prostate has mainly been described in immune-compromised patients. However, it can exceptionally be found as an isolated lesion in immune-competent patients. Tuberculosis of the prostate may be difficult to differentiate from carcinoma of the prostate and the chronic prostatitis when the prostate is hard and nodular on digital rectal examination and the urine is negative for tuberculosis bacilli. In many cases, a diagnosis of tuberculous prostatitis is made by the pathologist, or the disease is found incidentally after transurethral resection. Therefore, suspicion of tuberculous prostatitis requires a confirmatory biopsy of the prostate. We report the case of 60-year-old man who presented a low urinary tract syndrome. After clinical and biological examination, and imaging, prostate cancer was highly suspected. Transrectal needle biopsy of the prostate was performed and histological examination showed tuberculosis lesions.

L'angiomyolipome rénal est une tumeur rénale bénigne ayant une composante graisseuse. À travers une série de 8 cas nous montrons les critères diagnostiques et les particularités de prise en charges de l angiomyolipome rénal. Notre étude porte sur 8 cas d'angiomyolipomes rénaux durant une période de 4 ans, explorés par une échographie et une tomodensitométrie abdominales. le diagnostic a été retenu sur les données de l'imagerie dans tous les cas. Deux patients suivis pour une sclérose tubéreuse de Bourneville depuis l'enfance. L'âge moyenest de 42 ans. L'échographie aretrouvé un aspect hyperéchogène hétérogène dans tous les cas .La tomodensitométrie a permis la détection de la composante graisseuse. Le diagnostic radiologique de l'angiomyolipome rénal repose essentiellement sur la détection de la composante graisseuse. L'association à une sclérose tubéreuse de Bourneville est un argument diagnostique supplémentaire.

La fibrose rétropéritonéale (FRP) est une maladie rare. Elle se caractérise par la transformation progressive du tissu adipeux rétopéritonéal en une masse fibreuse qui enserre l'aorte, la veine cave inférieure et les voies urinaires responsable d'une altération progressive de la fonction rénale. Le mode habituel de présentation de cette maladie comporte l'association de douleurs lombaires, d'une insuffisance rénale, et d'un syndrome inflammatoire biologique. Nous rapportons 12 cas de fibrose rétropéritonéale dont nous précisons les particularités cliniques, radiologiques et thérapeutiques. Il s'agit d'une étude rétrospective portant sur douze cas de fibrose rétropéritonéale colligés au service d'urologie au CHU Hassan II de Fès durant une période de 9 ans (2005-2013). Il s'agissait de dix hommes et deux femmes. La symptomatologie clinique était très variable, dominée par la douleur lombaire qui était présente chez tous les malades et une hydrocèle chez un patient. Les explorations biologiques avaient montré une insuffisance rénale chez tous les malades et un syndrome inflammatoire chez dix patients. Le diagnostic de la maladie était suspecté dans tous les cas sur les données de l'échographie qui a montré une obstruction de la voie excrétrice supérieure sans obstacle visible chez tous les malades, et confirmé par la TDM abdominale sans injection du produit de contraste qui objectivait une lésion tissulaire rétropéritonéale engainant les vaisseaux et les voies urinaires. Dans notre série, la fibrose rétropéritonéale était idiopathique dans neuf cas. Elle était péri anévrysmale chez deux malades, et post radiothérapie chez un malade. Tous nos patients avaient bénéficié d'un drainage urinaire par sonde urétérale double J. Sept malades avaient reçu une corticothérapie. Une amélioration clinique et biologique, avec disparition de la douleur et amélioration de l'état général, a été observée chez 6 patients. A travers cette étude nous avons confirmé la rareté de la fibrose rétropéritonéale, la difficulté de son diagnostic, la fréquence de la douleur, du syndrome inflammatoire et de l'insuffisance rénale. La TDM abdominale sans injection du produit de contraste confirme le diagnostic. Le drainage urinaire est indispensable dans la plupart des cas et le suivi régulier des malades est nécessaire.

We report a rare case of an elderly woman presented with right renal mass with invasion of renal vein and several small lymphadenopathy in the hilar area .the diagnosis of kidney cancer is suspected and the patient underwent open radical nephrectomy, surrenalectomy and lymphadenectomy dissection. The pathologic examinations find a rosai dorfman disease. This unusual benign entity is uncommon in the kidney, but in medical imaging, it may simulate an infiltrative renal neoplasm, especially a lymphoma or leukemia or even renal cell carcinoma. A comprehensive literature review was undertaken to summarize the clinical and pathologic features of this disorder.Pan African Medical Journal 2016; 24

Urinary bladder calculi are rarely seen in women and any history of previous pelvic surgery must, therefore, raise suspicion of an iatrogenic etiology. According to the literature, fewer than 2% of all bladder calculi occur in female subjects and, thus, their presence should provoke careful assessment of the etiology. We report one case of a fragment of Foley catheter balloon as a cause of Bladder stone in 28 years old woman. We analyzed the diagnosis, aspect and therapeutic management of this case which is the first described in literature to our knowledge.

Background The current notion that cortico-striato-thalamo-cortical circuits are involved in the pathophysiology of obsessive-compulsive disorder (OCD) has instigated the search for the most suitable target for deep brain stimulation (DBS). However, despite extensive research, uncertainty about the ideal target remains with many structures being underexplored. The aim of this report is to address a new target for DBS, the medial dorsal (MD) and the ventral anterior (VA) nucleus of the thalamus, which has thus far received little attention in the treatment of OCD. Methods In this retrospective trial, four patients (three female, one male) aged 31–48 years, suffering from therapy-refractory OCD underwent high-frequency DBS of the MD and VA. In two patients (de novo group) the thalamus was chosen as a primary target for DBS, whereas in two patients (rescue DBS group) lead implantation was performed in a rescue DBS attempt following unsuccessful primary stimulation. Results Continuous thalamic stimulation yielded no significant improvement in OCD symptom severity. Over the course of thalamic DBS symptoms improved in only one patient who showed “partial response” on the Yale-Brown Obsessive Compulsive (Y-BOCS) Scale. Beck Depression Inventory scores dropped by around 46% in the de novo group; anxiety symptoms improved by up to 34%. In the de novo DBS group no effect of DBS on anxiety and mood was observable. Conclusion MD/VA-DBS yielded no adequate alleviation of therapy-refractory OCD, the overall strategy in targeting MD/VA as described in this paper can thus not be recommended in DBS for OCD. The magnocellular portion of MD (MDMC), however, might prove a promising target in the treatment of mood related and anxiety disorders.

La pyélonéphrite aigue emphysémateuse (PNE) est une forme grave d'infection rénale. Elle est grevée d'une lourde mortalité en dehors d'un traitement rapide et efficace. Notre travail vise à préciser les caractéristiques cliniques et paracliniques ainsi que les particularités de la prise en charge thérapeutique de cette pathologie et nous mettons l'accent sur la possibilité d'un traitement conservateur chez le diabétique. Nous avons analysé les dossiers médicaux des patients traités pour PNE au service d'urologie du CHU Hassan II de Fès entre Janvier 2004 et janvier 2010. Pour chaque dossier, nous avons précisé les caractéristiques cliniques, paracliniques et thérapeutiques ainsi que l'évolution après traitement. Il s'agissait de 5 patientes dont l'âge moyen était de 45,6 ans. Elles étaient toutes diabétiques. Une obstruction d'origine lithiasique des voies excrétrices supérieures a été retrouvée chez 3 patientes (60%). Le diagnostic avait été porté par l'intermédiaire de la tomodensitométrie (TDM) abdominale. Toutes les patientes avaient bénéficié des mesures de réanimation associant notamment une antibiothérapie et insulinothérapie. Le traitement chirurgical était conservateur dans tous les cas. En effet, un drainage chirurgical des collections péri rénales était réalisé dans deux cas, un drainage rénal percutané dans un cas et un drainage par une sonde urétérale double JJ dans 2 cas. L'évolution clinique et radiologique était excellente avec conservation rénale chez toutes les patientes. La pyélonéphrite emphysémateuse est une complication rare et grave, en particulier chez un patient diabétique. Le diagnostic positif sur la TDM. Le traitement chirurgical doit être conservateur au maximum, en dehors des formes graves, surtout chez le patient diabétique qui est un risque potentiel d'insuffisance rénale chronique.

The management of deep-seated cerebral cavernous malformations (CCMs) is still controversial. Although surgery remains the treatment of choice in patients with recurrent hemorrhage, patients with CCMs located in the brainstem are in many cases not eligible for resection due to high procedure-related morbidity and mortality. We evaluated the long-term outcome of LINAC radiosurgery (LINAC-RS) for the treatment of brainstem CCMs.Between December 1992 and March 2008, 14 patients (6 men, 8 women) harboring brainstem CCMs underwent LINAC-RS. Pretreatment neuroimaging showed no associated developmental venous angiomas (DVAs) in any of our patients. Prior to treatment, all patients suffered at least from one symptomatic hemorrhage (median 1.8, range 1–3). A median follow-up of 7.1 years (range 2.0–16.8 years) could be obtained in 12 patients. We applied a median tumor surface dose of 13.9 Gy (range 11–18 Gy; median tumor volume 1.6 ml, range 0.4–4.3 ml).Following LINAC-RS, neurological outcome improved in 4 (33.3%) and remained unchanged in 8 patients (66.7%). Rebleeding with subsequent transient neurological status deterioration occurred in 4 patients (33.3%), leading to additional surgical resection in 2 patients (16.7%). The corresponding annual hemorrhage rate was 4.8% (4/82.8 patient–years). Adverse radiation effects (ARE, defined by perilesional hyperintensity on T2-weighted MR images) were revealed in 3 patients (25%), leading to transient neurological deficits in 2 patients (16.7%). There were no procedure-related complications leading to either permanent morbidity or mortality.Our results support the role of LINAC-RS as an efficient and safe treatment to significantly reduce the annual hemorrhage rate in patients suffering from brainstem CCMs not eligible to microsurgery. Compared with radiosurgery for arteriovenous malformations (AVMs), the intervention-related morbidity is higher.

We present the long-term results of a consecutive series of patients with meningiomas treated by LINAC-radiosurgery using the micro-multi-leaf collimator technique (μMLC). Between May 2001 and July 2009, 78 patients (m:f = 24:54; median age, 56.8 years; range, 20.1–81 years) with 87 intracranial meningiomas (78 WHO I, seven WHO II, two WHO III) were treated with μMLC-LINAC radiosurgery at our institution, either as a primary or salvage treatment following one or more microsurgical procedures. Fifty-eight of 87 tumors (66.7%) were located in the skull base. The remaining 29 meningiomas (33.3%) were located in the convexity of the brain. The median tumor volume was 4.8 ml (range, 0.2–18.3 ml). The median tumor surface dose, maximal dose, and therapeutic isodose were 12 Gy, 16 Gy, and 75%, respectively. For retrospective evaluation, we included 70 patients (78 tumors) with a minimum radiological follow-up of 24 months. After a median follow-up of 79.7 months (range, 24.2–109.1 months), 24 patients (34.3%) improved in their clinical status (paresis of N. abducens 18/48, facial paresis 4/8, and hemiparesis 2/9), 41 patients remained stable (58.6%), three patients had treatment-related temporary complaints (4.3%); two patients developed vertigo, and one had a left-sided hemihypesthesia. All complaints recovered completely after steroid medication within 2 weeks. Two patients (2.8%) developed permanent trigeminal neuralgia. Follow-up MR images showed a partial remission in 21 tumors (26.9%) and a stable tumor size in 55 cases (70.5%). Two patients with high-grade meningiomas showed a tumor progression (one WHO II and one WHO III meningioma). At the end of follow-up (July 2010), the actuarial 5- and 9-year progression-free survival after radiosurgery were 98 and 96%, respectively. There was no treatment-related mortality. LINAC radiosurgery using a micro multi-leaf collimator for complex shaped intracranial meningiomas is effective yielding a high local tumor control, whereas the treatment-related morbidity remains low.

The optimal management of subtotally resected or recurrent malignant meningiomas remains controversial. We evaluated the efficacy of linear accelerator (LINAC) radiosurgery for atypical and anaplastic meningiomas after incomplete resection or treatment of recurrences. Between August 1990 and December 2003, 16 patients with 28 meningiomas WHO II and III were treated by stereotactic LINAC radiosurgery at our institution. The median radiological follow-up was 60.3 months, respectively (range: 7.2–173.9 months). Fourteen tumors in nine patients were classified as WHO II and 14 tumors in seven patients as WHO III. The median surface dose was 14 Gy (range: 10–15 Gy) with a median tumor volume of 4.8 ml (range: 0.51–51.4 ml). Clinical condition improved in four patients, remained unchanged in nine and deteriorated in one. Tumor shrinkage was seen in eight of 28 meningiomas and a stable disease in 12. Eight of 28 meningiomas showed local tumor progression. The overall tumor control rate (TCR) was 84%, 70%, 70% after 3, 5, 10 years. According to grading the corresponding TCR after 3, 5, 10 years was 91%, 81%, 81% for grade II and 77%, 60%, 60% for grade III meningiomas. Overall progression-free survival (PFS) was 74%, 67%, 58% after 3, 5, 10 years. According to grading the PFS after 3, 5, 10 years was 88%, 75%, 75% for grade II meningiomas and 57%, 57%, 43% for grade III meningiomas. Our results show the efficacy and safety of LINAC radiosurgery for incompletely resected or recurrent malignant meningiomas with a relatively high local tumor control and low morbidity.

The emerging field of organic/inorganic nanocomposites has become the focus of considerable research in recent years. In particular, graphene coated with iron oxide nanostructures are widely required for various applications. In this work, we report the preparation of graphene oxide/magnetite GO/Fe3O4 nanocomposite via a simple hydrothermal method. Our experimental results obtained by transmission electron microscopy (TEM) reveal that well defined Fe3O4 nanorods (NRs), about 8-11 nm in diameter and 50-60 nm in length, were uniformly anchored on graphene oxide nanosheets. X-ray diffraction (XRD) confirms the successful assembly of Fe3O4 on to GO nanosheets. Thermo gravimetric analysis results(TGA) show a good thermal stability for the nanocomposite. Raman laser studies carried out at various laser powers and acquisition times show that all the samples undergo changes in intensities and peak positions which reflect the modification of the electronic structure and electron-phonon interactions.

To evaluate the efficacy of interstitial radiosurgery (IRS) for pineal parenchymal tumors (PPTs).18 consecutively admitted patients (twelve male and six female, age range 6-68 years, median age 34 years) with PPTs (eight pineocytomas, ten malignant PPTs) were treated at the authors' institution with IRS using stereotactically guided iodine-125 seed implantation ((125)I-IRS) as either primary or salvage therapy. The cumulative tumor surface dose ranged from 40 to 64 Gy. Adjuvant radiotherapy of the whole brain or the craniospine was done in patients with grade III and grade IV PPT. The median follow-up period was 57.4 months (range 6-134 months).Overall actuarial 5- and 8-year survival rates after IRS were 100% and 86% for pineocytomas, and the overall actuarial 5-year survival rate was 78% for high-grade PPTs. Follow-up magnetic resonance imaging showed complete remission in 72% (13/18) and partial remission in 28% (5/18) of the cases. One patient developed an out-of-field relapse 4 years after partial remission of a pineocytoma, which had already been treated with IRS. There was no treatment-related mortality. Treatment-related morbidity occurred in two patients only.This study indicates that stereotactic (125)I-IRS for the management of PPTs is quite efficient and safe. Due to the low rate of side effects, IRS may develop into an attractive alternative to microsurgery in de novo diagnosed pineocytomas. In malignant PPTs, IRS may be routinely applied in a multimodality treatment schedule supplementary to conventional irradiation.

Exact simulations of solar cells require an efficient and accurate method able to model the device studied. For the case of the model single-diode/two resistors, five parameters must be identified the photo-generated current Iph, the reverse saturation current I0, the shunt resistance Rp, the series resistance Rs and the curve fitting parameter a (the ideality factor). This paper outlines a simple and accurate method for modeling of photovoltaic panels. The process just uses the normal data provided by the manufacturer to calculating the parameters of single-diode/two resistors model. An equation expressed as a function of Rs is solved numerically, while the other parameters depend exclusively on the series resistance are determined analytically. The accuracy of the resulting model is confirmed experimentally for two modules from different manufacturers and distinct technologies.

L'angiomyolipome rénal est une tumeur rénale bénigne ayant une composante graisseuse. À travers une série de 8 cas nous montrons les critères diagnostiques et les particularités de prise en charges de l angiomyolipome rénal. Notre étude porte sur 8 cas d'angiomyolipomes rénaux durant une période de 4 ans, explorés par une échographie et une tomodensitométrie abdominales. le diagnostic a été retenu sur les données de l'imagerie dans tous les cas. Deux patients suivis pour une sclérose tubéreuse de Bourneville depuis l'enfance. L'âge moyenest de 42 ans. L'échographie aretrouvé un aspect hyperéchogène hétérogène dans tous les cas. La tomodensitométrie a permis la détection de la composante graisseuse. Le diagnostic radiologique de l'angiomyolipome rénal repose essentiellement sur la détection de la composante graisseuse. L'association à une sclérose tubéreuse de Bourneville est un argument diagnostique supplémentaire.

Although microsurgery remains the first-line treatment, gross total resection of cystic craniopharyngeomas (CP) is associated with significant morbidity and mortality and the addition of external irradiation to subtotal resection proves to achieve similar tumor control. However, concern regarding long-term morbidity associated with external irradiation in children still remains. With this retrospective analysis, the authors emphasize intracavitary brachytherapy using phosphorus-32 (P-32) as a treatment option for children with cystic CP. Between 1992 and 2009, 17 children (median age 15.4 years; range 7–18 years) with cystic CP underwent intracavitary brachytherapy using P-32. Eleven patients were treated for recurrent tumor cysts; 6 patients were treated primarily. MR imaging revealed solitary cysts in 7 patients; 10 patients had mixed solid–cystic lesions (median tumor volume 11.1 ml; range 0.5–78.9 ml). The median follow-up time was 61.9 months (range 16.9–196.6 months). Local cyst control could be achieved in 14 patients (82 %). Three patients showed progression of the treated cystic formation (in-field progression) after a median time of 8.3 months (range 5.3–10.3 months), which led to subsequent interventions. The development of new, defined cysts and progression of solid tumor parts (out-of-field progression) occurred in 5 patients and led to additional interventions in 4 cases. There was neither surgery-related permanent morbidity nor mortality in this study. The overall progression-free survival was 75, 63, and 52 % after 1, 3, and 5 years, respectively. Intracavitary brachytherapy using P-32 represents a safe and effective treatment option for children harboring cystic CP, even as primary treatment. However, P-32 does not clearly affect growth of solid tumor parts or the development of new cystic formations.

Background The optimal treatment of glomus jugulare tumors (GJTs) remains controversial. Due to the critical location, microsurgery still provides high treatment-related morbidity and a decreased quality of life. Thus, we performed stereotactical radiosurgery (SRS) for the treatment of GJTs and evaluated the long-term outcome. Methods Between 1991 and 2011, 32 patients with GJTs underwent SRS using a linear accelerator (LINAC) either as primary or salvage therapy. Twenty-seven patients (median age 59.9 years, range 28.7–79.9 years) with a follow-up greater than five years (median 11 years, range 5.3–22.1 years) were selected for retrospective analysis. The median therapeutic single dose applied to the tumor surface was 15 Gy (range 11–20 Gy) and the median tumor volume was 9.5 ml (range 2.8–51 ml). Results Following LINAC-SRS, 10 of 27 patients showed a significant improvement of their previous neurological complaints, whereas 12 patients remained unchanged. Five patients died during follow-up due to old age or other, not treatment-related reasons. MR-imaging showed a partial remission in 12 and a stable disease in 15 patients. No tumor progression was observed. The actuarial overall survival rates after five, ten and 20 years were 100%, 95.2% and 79.4%, respectively. Conclusions Stereotactic LINAC-Radiosurgery can achieve an excellent long-term tumor control beside a low rate of morbidity in the treatment of GJTs. It should be considered as an alternative therapy regime to surgical resection or fractionated external beam radiation either as primary, adjuvant or salvage therapy.