Therapeutic Difficulty in a Case of Supratentorial Primitive Neuroectodermal Tumor Diagnosed during Pregnancy

Sarica, Feyzi Birol,Tufan, Kadir,Sen, Orhan,Erdogan, Bulent The Korean Neurosurgical Society 2009 Journal of Korean neurosurgical society Vol.45 No.1

We report a supratentorial primitive neuroectodermal tumor (sPNET) in 17-year-old primipara in the second trimester her pregnancy. Magnetic resonance imaging revealed a left frontoparietal mass with solid and cystic component. Gross-total resection was achieved via a left frontoparietal craniotomy. It was decided to suspend the radiotherapy and chemotherapy until the 30 weeks of gestation. But, a sudden uncal herniation was developed due to the reccurrence of the tumor and bleeding into the tumor at the 25 weeks of gestation and the patient died after urgent decompressive surgery. sPNETs is an extremely rare brain tumor in pregnancy and only two cases were reported in the literature to date. There is no universally agreed treatment protocol for sPNETs during pregnancy and a multidisciplinary approach is required in treatment. In the present study, the clinical, histopathological features and therapeutical difficulties of sPNETs diagnosed during pregnancy was discussed with the literature review.

Development of a fast transient simulator for gas-liquid two-phase flow in pipes

Choi, J.,Pereyra, E.,Sarica, C.,Lee, H.,Jang, I.S.,Kang, J. Elsevier 2013 Journal of petroleum science & engineering Vol.102 No.-

The objective of this study is to develop a simplified transient model and a simulator for gas-liquid two-phase flow in pipelines. The reliable predictions of liquid holdup and pressure drop are essential for pipeline design in oil and gas industry. In this study, the drift-flux approach is utilized to calculate liquid holdups. A modification of the power law correlation presented by Al-sarkhi and Sarica (2009) is suggested for pressure drop calculation. The proposed approach and correlation are continuous and flow pattern independent. Additionally, the developed model is simple and presents an easy tuning capability with either experimental data or synthetic data coming from steady state simulators. The simplicity of the model allows quick implementation yielding in a faster simulator as compared to available commercial software. The developed simulator is tested with Vigneron et al. (1995) experimental data, which include two transient conditions; liquid flow rate changes and gas flow rate changes. The results of simulation are compared with OLGA (OiL and GAs simulator supplied by SPT group) simulations and show fair agreement in terms of liquid holdups and pressures.

RELATIONSHIPS BETWEEN CUSP POINTS IN THE EXTENDED MODULAR GROUP AND FIBONACCI NUMBERS

Koruoglu, Ozden,Sarica, Sule Kaymak,Demir, Bilal,Kaymak, A. Furkan The Honam Mathematical Society 2019 호남수학학술지 Vol.41 No.3

Cusp (parabolic) points in the extended modular group ${\bar{\Gamma}}$ are basically the images of infinity under the group elements. This implies that the cusp points of ${\bar{\Gamma}}$ are just rational numbers and the set of cusp points is $Q_{\infty}=Q{\cup}\{{\infty}\}$.The Farey graph F is the graph whose set of vertices is $Q_{\infty}$ and whose edges join each pair of Farey neighbours. Each rational number x has an integer continued fraction expansion (ICF) $x=[b_1,{\cdots},b_n]$. We get a path from ${\infty}$ to x in F as $<{\infty},C_1,{\cdots},C_n>$ for each ICF. In this study, we investigate relationships between Fibonacci numbers, Farey graph, extended modular group and ICF. Also, we give a computer program that computes the geodesics, block forms and matrix represantations.

Relationships between cusp points in the extended modular group and Fibonacci numbers

¨Ozden Koruo˘glu,Sule Kaymak Sarica,Bilal Demir,A. Furkan Kaymak 호남수학회 2019 호남수학학술지 Vol.41 No.3

Cusp (parabolic) points in the extended modular group $\overline{\Gamma}$ are basically the images of infinity under the group elements. This implies that the cusp points of $\overline{\Gamma}$ are just rational numbers and the set of cusp points is $Q_{\infty}=Q\cup\left\{ \infty\right\} .$The Farey graph $F$ is the graph whose set of vertices is $Q_{\infty}$ and whose edges join each pair of Farey neighbours. Each rational number $x$ has an integer continued fraction expansion (ICF) $x=[b_{1},...,b_{n}].$ We get a path from $\infty$ to $x$ in $F$ as \TEXTsymbol{<}$\infty,C_{1},...,C_{n}>$ for each ICF. In this study, we investigate relationships between Fibonacci numbers, Farey graph, extended modular group and ICF. Also, we give a computer program that computes the geodesics, block forms and matrix represantations.

Update on Current Technologies for Deep Brain Stimulation in Parkinson’s Disease

Michelle Paff,Aaron Loh,Can Sarica,Andres M. Lozano,Alfonso Fasano 대한파킨슨병및이상운동질환학회 2020 Journal Of Movement Disorders Vol.13 No.3

Deep brain stimulation (DBS) is becoming increasingly central in the treatment of patients with Parkinson’s disease and other movement disorders. Recent developments in DBS lead and implantable pulse generator design provide increased flexibility for programming, potentially improving the therapeutic benefit of stimulation. Directional DBS leads may increase the therapeutic window of stimulation by providing a means of avoiding current spread to structures that might give rise to stimulation-related side effects. Similarly, control of current to individual contacts on a DBS lead allows for shaping of the electric field produced between multiple active contacts. The following review aims to describe the recent developments in DBS system technology and the features of each commercially available DBS system. The advantages of each system are reviewed, and general considerations for choosing the most appropriate system are discussed.

Hydrodynamics model for gas-liquid stratified flow in horizontal pipes using minimum dissipated energy concept

Lee, H.,Al-Sarkhi, A.,Pereyra, E.,Sarica, C.,Park, C.,Kang, J.,Choi, J. Elsevier 2013 Journal of petroleum science & engineering Vol.108 No.-

A new hydrodynamics model is proposed using minimum energy dissipation concept for gas-liquid stratified flow in horizontal pipes. It determines the liquid holdup and the pressure drop in gas-liquid stratified flow without the need of interfacial friction factor closure relationship. Model predictions show fair agreement when compared with experimental data and existing mechanistic models.

Effect of constipation on acute urinary retention following transrectal prostate biopsy

Cahit Sahin,Orhun Sinanoglu,Yavuz Karaca,Alpaslan Yuksel,Eyup Veli Kucuk,Kemal Sarica,Erhan Erdogan 대한비뇨의학회 2023 Investigative and Clinical Urology Vol.64 No.3

Purpose: To evaluate the possible effect of constipation on the acute urinary retention (AUR) after transrectal ultrasound-guided prostate biopsy (TRUS PB). Materials and Methods: A total of 1,167 patients with prostate-specific antigen (PSA) >4 ng/mL and/or abnormal digital rectal examination underwent a standard 12 core transrectal ultrasound-guided prostate needle biopsy in our hospital and the findings were examined prospectively. Chronic constipation (CC) was defined according to the Rome IV criteria. All cases were well evaluated with respect to clinical-histopathological factors; International Prostate Symptom Score (IPSS), prostate volume, post-void residue, age, body mass index, histopathological inflammation, and AUR. Results: The mean age of patients was 64.63±8.31 years, the PSA level was 11.60±16.83 ng/mL, and the prostate volume was 54.66±25.44 mL. In 265 cases (22.7%), CC anamnesis was present and AUR developed in 28 (2.4%) of the cases. In the multivariate analysis for the risk of developing urinary retention, prostate volume, pre-operative IPSS, and presence of CC requiring manual maneuvers to facilitate defecation were found to be risk factors (p=0.023, 0.010, and 0.001, respectively). Conclusions: Our findings demonstrated that CC may be a critical factor in the prediction of AUR formation following TRUS PB.

Radiological noninvasive assessment of ureteral stone impaction into the ureteric wall: A critical evaluation with objective radiological parameters

Ozlem Elibol,Kadihan Yalcin Safak,Ayse Buz,Bilal Eryildirim,Kutluhan Erdem,Kemal Sarica 대한비뇨의학회 2017 Investigative and Clinical Urology Vol.58 No.5

Purpose: To determine the predictive value of certain radiological parameters for an objective asssessment of the presence of ureteral stone impaction. Materials and Methods: Seventy-nine patients with a single proximal ureteral stones were retrieved from the departmental database. Both clinical and particularly radiological data of all cases were well evaluated on this aspect. In addition to the time period between the first colic attack and definitive management; diameter of proximal ureter and renal pelvis, longitudinal and transverse stone size, Hounsfied unit (HU) of the stone and lastly ureteral wall thickness at the impacted stone site were all carefully evaluated and noted. Results: Patients had a single proximal ureteral stone. While mean age of the cases was ranged 20 to 78 years; mean stone size was 15.62±4.26 mm. Evaluation of our data demonstrated that although there was a statistically significant correlation between ureteral wall thickness and patients age, transverse diameter of the stone, ureteral diameter just proximal to the stone, renal pelvic diameter and the duration of renal colic attacks; no correlation could be demonstrated between patients sex and the HU of the stone. Conclusions: Prediction of the presence and degree of proximal ureteral stone impaction is a challenging issue and our data indicated a highly significant correlation between ureteral wall thickness and the some certain radiological as well as clinical parameters evaluated which will give an objective information about the presence of impaction which may in turn be helpful in the follow-up and also management plans of such calculi.

Efficacy of magnetic resonance imaging for diagnosis of penile fracture: A controlled study

Erkin Saglam,Fatih Tarhan,Mustafa B. Hamarat,Utku Can,Alper Coskun,Emre Camur,Kemal Sarica 대한비뇨의학회 2017 Investigative and Clinical Urology Vol.58 No.4

Purpose: To evaluate the diagnostic value of magnetic resonance imaging (MRI) in patients with suspected penile fracture. Materials and Methods: A total of 122 patients admitted to our inpatient clinic with a suspicion of penile fracture following a recent history of penile trauma and who underwent surgical exploration were included this study. A thorough physical examination, a detailed medical history, description of the trauma, and preoperative International Index of Erectile Function (IIEF) scores were obtained for each patient prior to surgery. Thirty-eight of these patients were evaluated with MRI before the surgical exploration. Intraoperative findings were also recorded. Physical findings and IIEF scores were also recorded at postoperative 6 months. Results: The mean age of our patient group was 36.5±12.3 years. Penile fracture was detected in 105 of 122 patients in whom surgical exploration was performed owing to a suspected diagnosis. The mean time interval from penile trauma to hospital admittance was 9.9±15.1 hours. No cavernosal defect was detected in 9 of 84 patients (10.7%) who were not evaluated with MRI prior to surgery. Compared with surgical exploration, MRI findings showed 100% (30 of 30) sensitivity and 87.5% (7 of 8) specificity in the diagnosis of penile fracture. MRI had a high negative predictive value of 100% (7 of 7) and a positive predictive value of 96.7% (30 of 31) with just 1 misdiagnosed patient. Conclusions: MRI is a reliable diagnostic tool in the diagnosis of penile fractures. Compared to history and physical findings taken all together, the high sensitivity and specificity of this imaging technique can decrease the number of unnecessary surgical explorations.