Structural design of a positioning spherical parallel manipulator to be utilized in brain biopsy.

BACKGROUND: During the last decades, there has been a great increase in the usage of robotic systems during surgeries in order to reach increased operational precision, reduced operation times, enhanced recovery periods, low infection risks, and limited scar formations for aesthetic reasons. In light of this, the current study focuses on the field of robotic surgery by introducing the kinematic structure of the precise robotic positioning manipulator for brain biopsy. METHODOLOGY: Throughout the study, two degrees of freedom spherical parallel robot manipulator was proposed in order to position brain biopsy needle precisely during the brain biopsy operation on the target workspace. RESULTS: Direct and inverse kinematics of the manipulator were carried out parametrically by using quaternion algebra. The prototype of the manipulator was manufactured by rapid prototyping for hardware verification. CONCLUSIONS: Hardware verification of the manufactured prototype was completed distinctly by using motion capture cameras and manufactured mock-up setup that mimics tumour locations inside the brain. Successful verification results in terms of precision were achieved.

Splenic artery embolization with Ankaferd blood stopper in a sheep model.

PURPOSE: Splenic artery embolization is a minimally invasive therapeutic procedure utilized in a number of disorders. Ankaferd blood stopper (ABS) is a novel hemostatic agent with a new mechanism of action independent of clotting factors. We aimed to investigate the safety and efficiency of ABS for splenic artery embolization in a sheep model. METHODS: Seven adult female sheep were included in the study. Selective celiac angiography was performed using a 5F diagnostic catheter and then a 2.7F hydrophilic coating microcatheter was advanced coaxially to the distal part of the main splenic artery. Under fluoroscopic guidance, 6 mL mixture composed of half-and-half ABS and contrast agent was slowly injected. Fluoroscopy was used to observe the deceleration and stagnation of the flow. Control celiac angiograms were obtained immediately after the embolization. After the procedure, the animals were observed for one day and then sacrificed with intravenous sodium thiopental. RESULTS: Technical success rate was 100%. None of the animals died or experienced a major systemic adverse event during the procedure. All of the spleens appeared dark on macroscopic examination due to excessive thrombosis. Microscopically, the majority of the splenic sinusoids (90%-95%) were necrotic. CONCLUSION: In our study, splenic artery embolization by ABS was found to be safe and effective in the short-term. Further studies are needed to better understand the embolizing potential of this novel hemostatic agent.

Ultrasound validation of Trendelenburg positioning to increase internal jugular vein cross-sectional area in chronic dialysis patients.

BACKGROUND AND AIM: Trendelenburg positioning (TP) is a common approach used during internal jugular vein (IJV) cannulation. No evidence indicates that TP significantly increases the cross-sectional area (CSA) of the IJV or decreases the overlap between the carotid artery (CA) and the IJV in dialysis patients. The primary aim of this study was to investigate the effects of the TP on the CSA of the right IJV and on its relationship to the CA. METHODS: Thirty-seven consecutive hemodialysis patients older than 18 years of age were enrolled. We measured the CSA of the right IJV and overlap rate (at end-expiration at the level of the cricoid cartilage) between the CA and the IJV in two positions: State 0, table flat (no tilt), with the patient in the supine position; State T, in which the operating table was tilted to 15° of TP. RESULTS: Data were collected for all of the 37 patients enrolled in the study. The change in CSA and overlap between the CA and the IJV from the supine to the TP was not significantly different. The CSA was paradoxically decreased in 11 of 37 patients when changed from State 0 to State T. CONCLUSIONS: TP does not significantly increase the CSA of the right IJV or decrease the overlap between the CA and the IJV in dialysis patients. In fact, in some patients, it reduces the CSA. Therefore, the use of the TP for IJV cannulation in dialysis patients can no longer be supported.

Inframammarial Giant Fibroadenoma Removing and a Nipple-sparing Breast Reconstruction in an Adolescent: A Case Report.

Fibroadenomas are common, benign breast tumors that usually affect women in the second and third decade of life. Giant fibroadenomas often cause significant concern for the patient or family regarding malignant potential and altered breast development. Most fibroadenomas are benign. Local excision of small lesions through a circumareolar or inframammary incision rather than radical surgery is appropriate. Breast ultrasound represents the most commonly used imaging modality for the study of pediatric female breast masses and fibroadenomas. Detailed descriptions of the sonographic appearances of fibroadenomas in young girls are sparse. We believe that surgical treatment for the patient should include tumor extirpation and immediate restoration of breast appearance, minimizing visible scars, protection of the developing breast bud, nipple, and areola. This modality reduces psychosocial comorbidity.

Comparison of apparent diffusion coefficient values among different MRI platforms: a multicenter phantom study.

PURPOSE: We aimed to compare apparent diffusion coefficient (ADC) values among magnetic resonance imaging (MRI) scanners from different vendors. MATERIALS AND METHODS: We used a custom-made phantom solution consisting of distilled water, 0.9% NaCl, 25% NaCl, and shampoo for diffusion-weighted MRI (DW-MRI) examinations. DW-MRI was performed with similar sequence parameters using six different 1.5 Tesla MR scanners (scanners A-F). ADC maps were automatically constructed for all DW-MR images (b factors of 0 and 1000 s/mm(2)). ADC measurements were performed using regions of interest and seven different software programs, including four different postprocessing workstations, two different picture archiving and communication systems, and operator console software for each MR scanner. RESULTS: The ADC values generated by scanners A and F were higher and those of scanner B were lower than those generated by the other scanners (P = 0.002). The intravendor difference in the ADC values averaged from scanners D, E, and F was statistically significant (P < 0.001). The difference between the ADC values obtained by scanners C and E was not statistically different (P = 0.15). CONCLUSION: ADC values may differ among different MRI systems used for DW-MRI. Thus, the MRI vendor should be considered when using DW-MRI in a clinical setting.

Relationship between the right internal jugular vein and carotid artery at ipsilateral head rotation.

Ultrasound-guided right internal jugular vein catheterization (RIJV) should be the first choice to decrease the catheter-related complications in high-risk hemodialysis patients. For this procedure, clinicians should identify the optimum positions of the RIJV, including its lower overlap with the carotid artery (CA) and high cross-sectional area of the vein. The aim of this prospective randomized study to evaluate the effects of mild ipsilateral head rotation combined with Trendelenburg position on RIJV cross-sectional area and its relation to the CA in adult patients. Forty ASA I-II patients who were undergoing elective surgery were enrolled for this study. The subjects were asked to remain supine in the 15-20° Trendelenburg position. Two-dimensional ultrasound was then used to measure the degree of overlap between the RIJV and CA, the cross-sectional area of the RIJV. These measurements were compared between head rotation to the >30° left, <30° left, neutral, and <30° right positions. When the head was in the >30° left position, overlap was seen in 38 of 40 patients (95%). As the head was rotated from >30° left to <30° right, the CA-RIJV overlap (from 95% to 57.5%), and the cross-sectional area (from 14.2 mm to 8.7 mm) significantly decreased. In conclusion, when the head was turned to <30° right, the CA-RIJV overlap significantly decreased, and the cross-sectional area also decreased. When clinicians determine the optimal head position before RIJV cannulation, it is important to consider the advantages and disadvantages of the different head positions from >30° left to <30° right.

An unexpected cause of pleural effusion in paediatric emergency medicine.

Pancreaticopleural fistula (PPF) is an uncommon complication of chronic pancreatitis leading to a large and recurrent pleural effusion. Since the patients presented predominantly with respiratory symptoms, diagnosis and treatment were often delayed. We describe a child who was admitted to our paediatric emergency department with an acute onset of dyspnoea and unilateral massive pleural effusion caused by PPF. Multidetector CT is an easily accessible method that is able to show both the thoracic and abdominal findings non-invasively. The clinical and imaging features of this unusual entity are discussed.

Phenotyping of chronic obstructive pulmonary disease using the modified Bhalla scoring system for high-resolution computed tomography.

BACKGROUND: Identifying different phenotypes of chronic obstructive pulmonary disease (COPD) is important for both therapeutic options and clinical outcome of the disease. OBJECTIVE: To characterize the phenotypes of COPD according to high-resolution computed tomography (HRCT) findings; and to correlate HRCT scores obtained using the modified Bhalla scoring system with clinical and physiological indicators of systemic inflammation. METHODS: The present study included 80 consecutive patients with stable COPD. HRCT scans were evaluated by two independent radiologists according to the modified Bhalla scoring system. RESULTS: Fifty-four patients exhibited morphological changes on HRCT examination while 26 had no pathological findings. Patients with HRCT findings had lower spirometric measurements and higher levels of inflammation, and reported more exacerbations in the previous year compared with patients with no findings on HRCT. Patients with morphological changes were classified into one of three groups according to their HRCT phenotype(s): emphysema (E) only, E + bronchiectasis (B)/peribronchial thickening (PBT) or B/PBT only. Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC ratio, C-reactive protein (CRP) levels and the number of exacerbations among the groups were significantly different. Pairwise comparisons between the E only and E+B/PBT groups showed significantly lower FVC, FEV1 and FEV1/FVC values, and higher CRP levels and number of exacerbations compared with the B/PBT group. No significant differences were found between the E+B/PBT and the B/PBT groups. An inverse correlation was found between the total HRCT score and FVC, FEV1 and FEV1/FVC; the correlation was positive with CRP level, erythrocyte sedimentation rate and number of exacerbations. CONCLUSION: The present study exposed the intimate relationship between phenotype(s) characterized by HRCT and scoring for morphological abnormalities; and clinical and functional parameters and inflammatory markers. The inclusion of HRCT among routine examinations for COPD may provide significant benefits both in the management and prognosis of COPD patients.

Cortical and cerebellar atrophy, but no lesion in a patient with neuro-Behçet's disease.

Neuro-Behçet's disease (NBD) is a rare clinical entity. There are no reports about cortical atrophy in NBD. We report a patient with NBD exhibiting only cortical and cerebellar atrophy without any lesions. A 38-year-old male was hospitalized due to gait disorder. He had experienced forgetfulness, irritability, sexual and behavioral dyscontrol, and incontinence for 5 years. Magnetic resonance imaging (MRI) showed cortical and cerebellar atrophy, but there were no lesions. In the differential diagnosis of NBD, physicians should take into account the presence of both brainstem and cerebellar and cortical atrophy even in the absence of typical lesions for NBD, particularly in the presence of cognitive dysfunctions.

Optimal angle of needle entry for internal jugular vein catheterization with a neutral head position: a CT study.

PURPOSE: The aim of this study is to determine the optimal angle of needle entry in the sagittal plane for internal jugular vein (IJV) catheterization with the central approach while the head is in the neutral position. METHODS: The contrast-enhanced carotid artery computed tomography angiographies of 123 consecutive patients were retrospectively reviewed. The point of merger between the sternal and clavicular heads of the sternocleidomastoid muscle was assumed as a clinical entry (CE) point. The angle between CE point and the center of the IJV, the depth, diameter of the vessels and the degree of overlap between the IJV and carotid artery (CA) were measured. RESULTS: The angles between the CE point and the center of the IJVs were similar, 7° ± 13° medial and 8° ± 12° medial on the right and the left side, respectively. The center of IJVs from the CE point was between 0° and 16° toward the medial in 79.8% on the right side and 89.9% on the left side of patients. The diameters of the right IJVs were greater than the left IJVs (p = 0.001). The depth from the skin and overlap between IJV and CA did not vary between the two sides. CONCLUSIONS: When a central approach is used for right internal jugular vein (RIJV) cannulation with a neutral head position, the orientation of the angle of needle entry (i.e., 16°) medially in the sagittal plane may quadruple the success rate of RIJV catheterization compared to the success rate of a laterally oriented angle of entry as recommended by the classic method.

Left femoral vein is a better choice for cannulation in children: a computed tomography study.

BACKGROUND: Central venous catheters are often required in emergency rooms and intensive care and/or those undergoing major surgical procedures. In this study, we aimed to gain a better understanding of the anatomy of the femoral vessel in relation to central venous cannulation. METHODS: The right and left (total of 180) femoral veins (FVs) of 90 consecutive pediatric patients were retrospectively evaluated using computed tomography images. Patients were divided into two groups according to their age: group 1, patients up to 9 years of age; and group 2, patients between 9 and 16 years of age. RESULTS: The position and overlap of femoral artery (FA) to FV are significantly different between the left and right sides in both groups (P = 0.001). The left FV was most commonly located medial to the FA. However, the right FV was most commonly located posterior-medial to the FA. The incidence of overlap of the FA over the FV was significantly lower at the left side in both groups. CONCLUSION: The incidence of overlap of the FA over the FV was significantly lower at the left side in pediatric patients. This finding was similar between the patients aged 2-8 years and those aged 9-16 years and may have significant clinical implications. Guiding clinicians to select the left FV of children for cannulation may result in lower arterial puncture rates while accessing the central vein.

Short-term effects of Ankaferd hemostat for renal artery embolization: an experimental study.

PURPOSE: Renal artery embolization (RAE) is a minimally invasive therapeutic technique that is utilized in a number of disorders. Ankaferd is a novel hemostatic agent with a new mechanism of action independent of clotting factors. We used Ankaferd for RAE in a sheep model. METHODS: Seven adult female sheep were included in the study. Selective renal arteriogram using 5-F diagnostic catheter was performed to make sure that each kidney was fed by a single renal artery and the animal had normal renal vasculature. Coaxial 2.7-F microcatheter was advanced to the distal main renal artery. Under fluoroscopic guidance, 2 mL of Ankaferd mixed with 2 mL of nonionic iodinated contrast agent was slowly injected. Fluoroscopy was used to observe the deceleration of flow and stagnation. Control renal angiograms were performed just after embolization. After the procedure, the animals were observed for 1 day and then sacrificed with intravenous sodium thiopental. RESULTS: The technical success was observed in seven of the seven animals.. After embolization procedure, none of the animals died or experienced a major systemic adverse event. On macroscopic examination of the embolized kidneys, thrombus at the level of main renal artery formed after Ankaferd embolization was more compact compared with the thrombi that was not Ankaferd-associated, which was observed elsewhere. Microscopically, majority of the renal tubular cells (80-90 %) were necrotic, and there was epithelial cell damage in a small portion of the cells (10-20 %). CONCLUSIONS: RAE was safe and effective in the short-term with Ankaferd in studied animals. Further studies should be conducted to better delineate the embolizing potential of this novel hemostatic agent.