Microvascular Decompression for Hemifacial Spasm without the Use of Neuromonitoring and Fix Retraction: A Single-Center Experience.

AIM: To evaluate outcome of patients with hemifacial spasm surgically treated by microvascular decompression without the use of neuromonitoring and fix retraction. MATERIAL AND METHODS: Of the 78 patients with hemifacial spasm operated by the senior author of this study between 2016 and 2020, 60 patients who were followed up were included and retrospectively investigated. The female:male ratio was 32:28, and the mean age was 42.5 ± 11.5 years (range 23?71 years). All the patients were operated via the lateral retrosigmoid suboccipital infrafloccular approach, and no permanent retractor was employed during the procedures. Additionally, intraoperative neuromonitoring was not performed for any of the patients. RESULTS: Single vessel compression was observed in 77% of the patients, whereas 16% and 6% experienced compression in two and three vessels, respectively. Immediate recovery was achieved in 70% of the patients. Half of the remaining 30% fully recovered within 6 months?2 years. Furthermore, the complaints of 5% of the patients were alleviated, whereas no improvement was observed in 10% of the patients. One patient developed a recurrence. CONCLUSION: Microvascular decompression is a highly effective method for the treatment of hemifacial spasm. In this study, we did not resort to intraoperative neuromonitoring and observed that our postoperative complication rates were consistent with the existing literature.

Evaluation of Percutaneous Unilateral Kyphoplasty Results in Osteoporotic Vertebral Compression Fractures Using Individual 3D Printed Guide Template Support.

AIM: To compare the clinical and radiological outcomes of unilateral percutaneous kyphoplasty (PKP) surgeries performed using 3D printing technology in patients with osteoporotic compression fractures to conventional unilateral PKP surgeries. MATERIAL AND METHODS: Patients with acute painful single-level osteoporotic vertebral compression fracture (OVCF) who need surgical treatment were divided into two groups: group A (patients who had 3D template-guided PKP) and group B (patients who conventional PKP). To compare the two surgical procedures, Total Absorbed Radiation Dose (TARD), pre- and postoperative visual analog scale (VAS) scores, and Total Surgery Time (TST) were calculated and compared between groups in both surgical groups. RESULTS: A total of 44 patients with single-level OVCF who were experiencing acute pain were successfully operated on, with 22 patients in each group. TARD (2.6 ± 0.4 mGy vs. 6.1 ± 1.9 mGy, p < 0.05) and TST (12.4 ± 2.6 min vs. 20.2 ± 3.2 min, p < 0.05) differed significantly different between groups A and B. There was no statistically significant difference between the patient groups in preoperative and postoperative VAS values (p > 0.05). Cement leakage was lower in group A (3/22, 13.6%) than in group B (6/22, 27.3%) (p > 0.05). There were no neurological complications or infections in either group. CONCLUSION: When compared to the conventional procedure, the unilateral percutaneous kyphoplasty method was supported by a 3D printing guide template. By reducing operative time and radiation exposure, tt has resulted in a more effective surgical procedure for patients and a safer surgical procedure for surgeons and anaesthesiologists.

Importance of Preoperative Vertical Geometric Analysis in Surgery for Anterior Communicating Artery Aneurysm.

OBJECTIVE: In this study, we analyzed the vertical geometry of the anterior communicating artery (AComA) complex with the aim to improve the surgical site orientation during aneurysm operations. Further, the geometric data that can contribute to the success of the surgical technique applied for AComA aneurysms are reported. METHODS: Computed tomography angiography data of the cerebral arteries of 100 patients who visited our clinic were analyzed. A three-dimensional examination was performed according to the Frankfurt horizontal plane (FHP) using the RadiAnt DICOM Viewer (Medixant, Poznan, Poland), and vertical measurements of the AComA complex were calculated. RESULTS: The Willis polygon values were found to be consistent with those in the literature. The mean height of the AComA complex was 30.58 ± 4.80 mm according to the FHP. CONCLUSIONS: Preoperative evaluation of the vertical geometry of the AComA complex is essential for AComA aneurysm surgery. The height of the AComA complex is a key parameter affecting intraoperative surgical site visibility. Preoperative calculation of the height of the AComA complex relative to FHP can facilitate intraoperative surgical site orientation.

Preoperatively, Which Parameter Allows Us to Predict the C5 Palsy After Cervical Open-Door Laminoplasty?

AIM: To uncover factors that can predict the development of C5 palsy before surgery by evaluating several different parameters. MATERIAL AND METHODS: A total of 177 patients who underwent surgery between 2015 and 2020 were included in the study. In total, C5 palsy was observed in 22 (12.4%) of our patients. The radiological and clinical data of the patients were retrospectively analyzed and added to the data. RESULTS: A total of 177 patients who satisfied the criteria were included in the study, among whom 117 (66.1%) and 60 (33.9%) were male and female, respectively. Patients with ossified posterior longitudinal ligament (OPLL) (92; 52.0%) needed surgery the most. C5 palsy developed in 16/92 (17.3%) patients who had surgery for OPLL. This result was statistically significant (p < 0.001). However, a significant difference in the postoperative Pavlov ratio was noted between both groups (p=0.027). The foraminal dimensions for the C5 palsy group were significantly lower than those for the non-C5 palsy group. CONCLUSION: Smaller C5 root foramina diameter measurements were the most important predictive factor for the development of C5 palsy after open-door cervical laminoplasty. Although the pathophysiology remains to be fully understood, ischemia-reperfusion injury supposedly plays a role therein.

Is Balloon Kyphoplasty Effective for Bone Remodeling of AO-Type A3-4 Fractures at the Thoracolumbar Junction?

AIM: Vertebral compression fractures (VCF) occur most commonly at the thoracolumbar junction (TLJ). Balloon kyphoplasty (BKP) is an effective method of bone remodeling in these cases. In this study, we evaluate the parameters that affect bone retropulsion and restoration in TLJ VCF without neurological deficits. MATERIAL AND METHODS: Thirty-one of Frankel E and AO A3-4 type VCFs fractures at the TLJ, with bone retropulsion into the spinal canal, from 2017 to 2020, were evaluated retrospectively. Data was gathered on patient demographics and medical histories. Measurements of anterior vertebral heights, posterior vertebral heights, local kyphotic angles, spinal cord area, and bone retropulsion into the spinal canal (BRC) were evaluated preoperatively, early postoperatively, and late postoperatively. RESULTS: In those patients who underwent early surgery ( 4 weeks postfracture), a significantly greater increase in anterior vertebral heights was seen between early postoperative and preoperative measurements than in patients who underwent late surgery ( 4 weeks postfracture) (p = 0.016). At the six-month follow-up, a significantly greater decrease in local kyphotic angle measurements was seen in patients over 65 years of age than those under 65 (p = 0.023). Comparison of local kyphotic angles between sexes revealed a significant decrease in measurements at follow-up in female patients (p = 0.029). Both early postoperative and late postoperative local kyphotic angle measurements of patients with a body mass index (BMI) ≥25 were significantly lower than those of patients with a BMI 25 (p = 0.012). CONCLUSION: The restoration of vertebral angles and heights with the maximum level of BKP can effectively reduce BRC.

What is the Effect of Pedicle Screw Reinsertion Through the Same Trajectory on Pullout Strength?

AIM: To investigate the pullout strength of a pedicle screw reinserted through the same trajectory MATERIAL and METHODS: Fifty freshly frozen lamb L4 vertebrae were divided into the following five groups: Group 1, inserted with a 5-mm pedicle screw; Group 2, inserted with a 5-mm pedicle screw followed by the removal and reinsertion of the same screw after control; Group 3, inserted with a 5-mm pedicle screw followed by the removal and reinsertion of a 5.5-mm screw after control; Group 4, inserted with a 5.5-mm pedicle screw; and Group 5, inserted with a 5.5-mm pedicle screw followed by the removal and reinsertion of the same screw after control. Pedicle screws were inserted into the right pedicles, and axial pullout testing was performed at 5 mm/min. All data were recorded. A load-displacement curve was used to obtain the peak value of the pullout strength for all specimens. RESULTS: The mean pullout strengths were 1086.22 N, 1043.32 N, 1039.18, 1199.10, and 1131.68 N for Groups 1?5, respectively. No significant difference was observed among all groups (p > 0.05). CONCLUSION: Perioperative reinsertion of the same screw or (0.5 mm) larger in diameter through the same trajectory after the control of the screw trajectory did not affect the pullout strength of the screw.

Comparison of cerebral AVMs in patients undergoing surgical resection with and without prior endovascular embolization.

AIM: Brain arteriovenous malformations (AVMs) are congenital anomalies that present as intracranial hemorrhage or epilepsy. AVMs often remain clinically silent for extended periods. Although AVM treatment methods are controversial, three treatment strategies are usually combined or applied alone: surgical removal, embolization and stereotactic radiosurgery. We compared clinical and radiological outcomes in intracranial AVM patients treated via surgical resection with and without prior embolization. MATERIALS AND METHODS: Patients who did (30 patients) and did not (30 patients) undergo endovascular embolization before surgical resection at the Izmir Katip Çelebi University Atatürk Training and Research Hospital Neurosurgery Clinic from 2011 to 2019 were included in this retrospective, cohort study. Symptoms at diagnosis, comorbidities and clinical (AVM and Spetzler-Martin grade) and morphological characteristics were assessed. RESULTS: A mean one-year follow-up assessed outcomes using the modified Rankin score, and imaging studies assessed AVM obliteration post-procedure. Mean operation times for surgical resection with and without embolization were 166.50 ± 32.02 and 204.47 ± 26.66 min, respectively. Mean patient hospitalization periods for surgical resection with and without embolization were 8.43 ± 3.60 and 12.00 ± 5.51 days, respectively. CONCLUSION: Among patients who underwent surgical resection, significant operation time and hospitalization time differences were observed in favor of patients who underwent embolization, indicating that preoperative embolization is a safe and beneficial method for treating ruptured and non-ruptured AVMs.

Caregiver burden in cerebral palsy: Validity and reliability of the Turkish version of caregiver difficulties scale.

BACKGROUND: This study aims to translate the caregiver difficulties scale (CDS) into Turkish language and to reveal its reliability and validity in Turkish informal family caregivers of children with cerebral palsy (CP). METHODS: This study included 130 participants (39.9 ± 7.8 years; range 24-58 years; 106 females and 24 males). Demographic properties of participants, relationship with the care recipient, income, caregiving time, CP type and diseases of the child (e.g., epilepsy, hydrocephalus and congenital heart disease) and the caregiver were recorded. The CDS, caregiver well-being scale (CWBS), World Health Organization Quality of Life (WHOQOL-BREF) and Beck depression inventory (BDI) were used for data collection. The internal consistency of the CDS was assessed using the calculation of Cronbach's alpha coefficient. A test-retest interval of 2 weeks was used to assess the reliability. The intercorrelation of variables was evaluated using the Spearman correlation coefficient. The receiver operating characteristic (ROC) analysis was performed to find the predictive power of CDS scores for depression. RESULTS: A total of 130 family caregivers of children with CP completed the test/retest procedures. The Cronbach alpha coefficients were found as 0.878 for the test and 0.852 for the retest. Intraclass correlation coefficient (ICC) value was found between 0.83 and 0.90 for test-retest reliability of the CDS. In addition, the CDS showed a significantly strong correlation with CWBS-activities of living subscale and WHOQOL-BREF psychological, physical and environment domains, as well as a significantly moderate correlation with CWBS basic needs subscale, BDI and WHOQOL-BREF general health and social domains. CDS scores that are >46 resulted in a sensitivity of 81.48% and a specificity of 73.79% for moderate-severe depression. CONCLUSION: The Turkish version of the CDS is a valid and reliable measure for caregiver burden of family caregivers of children with CP.

The importance of preoperative planning to perform safely temporal lobe surgery.

Neurosurgeons should know the anatomy required for safe temporal lobe surgery approaches. The present study aimed to determine the angles and distances necessary to reach the temporal stem and temporal horn in surgical approaches for safe temporal lobe surgery by using a 3.0 T magnetic resonance imaging technique in post-mortem human brain hemispheres fixed by the Klingler method. In our study, 10 post-mortem human brain hemisphere specimens were fixed according to the Klingler method. Magnetic resonance images were obtained using a 3.0 T magnetic resonance imaging scanner after fixation. Surgical measurements were conducted for the temporal stem and temporal horn by magnetic resonance imaging, and dissection was then performed under a surgical microscope for the temporal stem. Each stage of dissection was achieved in high-quality three-dimensional images. The angles and distances to reach the temporal stem and temporal horn were measured in transcortical T1, trans-sulcal T1-2, transcortical T2, trans-sulcal T2-3, transcortical T3, and subtemporal trans-collateral sulcus approaches. The safe maximum posterior entry point for anterior temporal lobectomy was measured as 47.16 ± 5.00 mm. Major white-matter fibers in this region and their relations with each other are shown. The distances to the temporal stem and temporal horn, which are important in temporal lobe surgical interventions, were measured radiologically, and safe borders were determined. Surgical strategy and preoperative planning should consider the relationship of the lesion and white-matter pathways.

Three-Dimensional Printing Assisted Preoperative Surgical Planning for Cerebral Arteriovenous Malformation.

OBJECTIVE: The aim of this study to investigate the benefits of patient-based 3-dimensional (3D) cerebral arteriovenous malformation (AVM) models for preoperative surgical planning and education. METHODS: Fifteen patients were operated on for AVMs between 2015 and 2019 with patient-based 3D models. Ten patients' preoperative cranial angiogram screenings were evaluated preoperatively or perioperatively via patient-based 3D models. Two patients needed emergent surgical intervention; their models were solely designed based on their AVMs and used during the operation. However, the other patients who underwent elective surgery had the modeling starting from the skull base. These models were used both preoperatively and perioperatively. The benefits of patients arising from treatment with these models were evaluated via patient files and radiological data. RESULTS: Fifteen patients (10 males and five females) between 16 and 66 years underwent surgery. The mean age of the patients was 40.0±14.72. The most frequent symptom patients observed were headaches. Four patients had intracranial bleeding; the symptom of admission was a loss of consciousness. Two patients (13.3%) belonged to Spetzler-Martin (SM) grade I, four (26.7%) belonged to SM grade II, eight (53.3%) belonged to SM grade III, and one (6.7%) belonged to SM grade IV. The mean operation duration was 3.44±0.47 hours. Three patients (20%) developed transient neurologic deficits postoperatively, whereas three other patients died (20%). CONCLUSION: Several technological innovations have emerged in recent years to reduce undesired outcomes and support the surgical team. For example, 3D models have been employed in various surgical procedures in the last decade. The routine usage of patient-based 3D models will not only support better surgical planning and practice, but it will also be useful in educating assistants and explaining the situation to the patient as well.

Early Experience with Salvage Robotic-Assisted Radical Prostatectomy in Proton Beam Radiotherapy Failures.

AIMS: To assess the perioperative and short-term functional and oncologic outcomes of the salvage robot-assisted radical prostatectomy (sRARP), after recurrence following primary proton beam therapy for clinically localized prostate cancer. METHODS: Ten patients undergoing sRARP after failure of the prior definitive proton beam therapy for localized prostate cancer were included. BCR is defined as a prostate-specific antigen (PSA) value of 2.0 ng/mL greater than the absolute nadir. All of the individuals had a diagnosis of prostate cancer via biopsy after proton beam therapy, with negative findings on magnetic resonance imaging/computer tomography of the pelvis and abdomen, and a bone scan. The sRARP procedure with pelvic lymph node dissection was performed by a single surgeon in all patients. RESULTS: The median age of the cohort at sRARP was 66.8 years, and the mean BMI was 29.2 kg/m2. The mean duration from proton beam therapy to sRARP was 58.4 months; the mean preoperative PSA level was 5.5 ng/mL, the mean operative time was 230 minutes, and the approximate blood loss was 745 mL. Anastomotic leakage occurred in half of the individuals, and bladder neck contracture developed in 6 patients. For 8 patients, the continence results within 6 months followup were available. Overall, 24 complications occurred in 9 patients. At follow-up in the 32nd month, the overall survival rate was 80%, and the BCR-free survival rate was 90%. CONCLUSION: sRARP after proton beam therapy is an applicable procedure, but has a high risk of serious complications.

Are 3D Printing Templates an Advantage in Upper Thoracic Pedicle Screw Fixation?

Background This study aims to compare the clinical results of patients with upper thoracic vertebral fractures treated with pedicle screw and posterior spinal fusion with preoperative surgical planning and 3-dimensional (3D) modeling and patients treated with freehand screws. Methods Fifty patients who underwent pedicle screw placement with a diagnosis of upper thoracic fracture between June 2018 and October 2020 were included in our study. Pedicle screws were used in 25 patients (group 1) after the planning was completed with the help of 3D preoperative printing and modeling. Pedicle screws were applied in 25 patients in the control group (group 2) using the freehand technique. Intraoperative bleeding amount, operation time, and correct screw placement data in both groups were recorded. Results The operation time was 134 ± 22 minutes for group 1 and 152 ± 38 minutes for group 2. The difference in operation times was found to be statistically significant (p < 0.05). Based on axial and sagittal reconstruction images, the accuracy rate of pedicle screw placement (grades 0 and 1) in group I was 96.6% compared to 83.6% in group II. The minor perforation rate (grade 1, <2 mm) was 5.8% in group I compared to 11.8% in group II. The moderate perforation rate (grade 2, 2-4 mm) was 3.4% in group I compared to 14% in group II. The severe perforation rate (grade 3, >4 mm) was 2.3% in group II; however, misplaced screws were not associated with neurological deficits. The difference in overall accuracy rates between the two groups was significant (p < 0.05). Conclusions For 3D models of upper thoracic pedicle screw insertion, guide plates can be produced inexpensively and individually. It provides a new method for the accurate placement of upper thoracic pedicle screws with high accuracy and secure use in screw insertion.

Edema-mass Ratio Based On Magnetic Resonance Imaging As A Preoperative Diagnostic Factor For Posterior Fossa Metastasis.

BACKGROUND: Peritumoral edema of primary brain tumors is an important cause of morbidity and mortality. The number of studies currently available on the prognostic role of peritumoral brain edema in the posterior fossa is extremely limited. OBJECTIVE: Based on the known importance of magnetic resonance imaging in diagnosing supratentorial metastases, this study aimed to investigate the effects of peritumoral edema on survival of patients with posterior fossa metastases and the preoperative diagnostic value of MRI. METHODS: Edema and mass volumes of 49 patients with posterior fossa metastasis, who underwent surgery during 2012-2016, were measured using magnetic resonance imaging. The edema/mass indices were retrospectively calculated and interpreted by evaluating the demographic, clinical, and survival data. RESULTS: The study consisted of 32 (65.3%) male and 17 (34.7%) female participants, with the mean age ± standard deviation of 47.25±29.25 (17-81) years. Among the 49 patients with posterior fossa metastases, 34 (69.4%) had carcinoma, while 15 (30.6%) had non-carcinoma metastases. The edema/mass indices of patients with carcinoma and non-carcinoma metastases were found to be 14.55±9.64 and 1.34±1.08, respectively, and the difference was statistically significant (p<0.001). The mean survival of patients with carcinoma and non-carcinoma metastases was found to be 642±11.52 days and 726±9.32 days, respectively; however, this difference was not statistically significant (p=0.787). CONCLUSION: The edema/mass ratio was found to be a significant diagnostic factor for the prediction of posterior fossa metastases. Further detailed studies are warranted to investigate the effect of edema/mass ratio on survival rate.

3.0 Tesla MRI scanner evaluation of supratentorial major white matter tracts and central core anatomical structures of postmortem human brain hemispheres fixed by Klingler method.

Background: As an advanced imaging technique for the human brain, the importance of magnetic resonance imaging technique (MRI) is indisputable. The study aims to contribute to the literature by imaging post-mortem human brain hemispheres fixed with the Klinger method through the a 3.0 Tesla MRI Scanner and by defining the supratentorial major white matter tracts and central core anatomical structures.Methods: In our study, 10 post-mortem human brain hemisphere specimens were placed in 10% formalin solution for at least two months according to the Klingler method. The images were obtained using a 3.0 Tesla MRI Scanner. Anatomical structures were described on the T1-T2 axial, coronal, and sagittal MRI sections and compared with control images obtained from healthy humans.Results: Our examination revealed major association fibers, the basal cores and nuclei were denser, and the connections between them were clearly visible. The basal nuclei particularly were visualized more clearly compared with the normal MRI examinations. The claustrum, putamen, lateral and medial part of globus pallidus, and the caudolenticular bridges of the caudate nucleus could be clearly distinguished. The optic radiation line toward the occipital area as well as the forceps major and minor were distinct in the axial sections. Meanwhile, the imaging emphasized the importance of temporal stem, and the fibers it contained were clearly observed in the coronal sections.Conclusion: The use of hemispheres fixed using the Klinger method in post-mortem MRI examinations on brain hemispheres showed a clear separation of white matter fibers and nuclear structures.

Hydrogen Peroxide Sensors Based on Fluorescence Quenching of the 2-AminobenzimidazoleFluorophore.

The fluorescence emission of the parent 2-aminobenzimidazole (ABZ, 1), the mono- and disubstituted derivatives (2, 3), 2-aminonaphthoimidazole (4), and 4-amino dinaphthodiazepine 5 (λem = 315-400 nm) is strongly quenched in the presence of aqueous hydrogen peroxide. The quenching process is dual: for diazepine 5, quenching is dynamic at lower H2O2 concentrations with linear reduction of the fluorescence lifetime from 4.3 to 2.6 ns. At higher H2O2 concentrations, a second species appears in the absorption and emission spectra with fluorescence lifetimes of 1.3 ns, indicating the formation of a new (ground-state) hydrogen-bonded ABZ-H2O2 complex (static quenching). Sensors 1 and 2 show also dual quenching that fits with a static 1:1 and 1:2 model with K1:1 = 8(11) M-1 and K1:2 = 21(147) M-1 for 1(2). The formation of a 1:2 complex (1:(H2O2)2) is also supported by density functional theory (DFT) calculations and spectra simulations.

Comparison of Biomechanical Properties of Dura Mater Substitutes and Cranial Human Dura Mater : An In Vitro Study.

OBJECTIVE: The aim of this study was to investigate the biomechanical differences between human dura mater and dura mater substitutes to optimize biomimetic materials. METHODS: Four groups were investigated. Group I used cranial dura mater (n=10), group II used Gore-Tex® Expanded Cardiovascular Patch (W.L. Gore & Associates Inc., Flagstaff, AZ, USA) (n=6), group III used Durepair® (Medtronic Inc., Goleta, CA, USA) (n=6), and group IV used Tutopatch® (Tutogen Medical GmbH, Neunkirchen am Brand, Germany) (n=6). We used an axial compression machine to measure maximum tensile strength. RESULTS: The mean tensile strengths were 7.01±0.77 MPa for group I, 22.03±0.60 MPa for group II, 19.59±0.65 MPa for group III, and 3.51±0.63 MPa for group IV. The materials in groups II and III were stronger than those in group I. However, the materials in group IV were weaker than those in group I. CONCLUSION: An important dura mater graft property is biomechanical similarity to cranial human dura mater. This biomechanical study contributed to the future development of artificial dura mater substitutes with biomechanical properties similar to those of human dura mater.

Craniometric Analysis of Skullbase With Magnetic Resonance Imaging in Patients With Chiari Malformation.

Basilar invagination, Platibasi, increased tentorium angle, and posterior fossa hypoplasia are the anomalies associated with Chiari malformation. When Chiari is symptomatic; tonsillary ectopenia appears to be a definitive criterion for diagnosis and treatment, the detection of additional anomaly may alter the surgical outcome. The aim of this study is to investigate the relationship between tonsillar ectopia and other anomalies.The authors retrospectively reviewed 31 cases which had Chiari Malformation at our Hospital. There were 8 men (25.8%) and 23 female (74.2%). Average age of the samples is 37.93 ±â€Š12.93 years. Seventeen patients (54.8%) had tonsillar ectopia 0 to 5 mm, 14 patients had tonsillar ectopia over 5 mm. Seven patients had syrinx (22.6%), 2 patients had mild hydrocephalus (6.5%). Six patients had surgery for the treatment. The mean length of the clivus was 39.3 mm, supraoksiput length was 40.4 mm, cerebellar hemisphere length was 61.08 mm, Mc Rae line was 33.14 mm, Twinning Line was 79.4mm, and Tentorium-Twinning line angle was 40.35°. There was no significant difference between Tonsillar ectopia, syrinks, and hydrocephalus. Basilar invagination had relationship between platibasi (6 patients had platibasi according to 2 mm criteria, 2 patients had platibasi according to 5 mm criteria (P < 0.05). Patients with syrinx had relationship between Chamberlain line (P < 0.05).In the authors' study, although there was no statistically significant difference between the tonsillary ectopia and the criteria of these anomalies, the relationship between basilar invagination and platibasi was significant.

Three Dimensional Printing and Biomaterials in the Repairment of Bone Defects; Hydroxyapatite PLA Filaments

Background/aim: Application fields of bone tissue engineering studies continue to expand. New biocompatible materials aimed to improve bone repairment and regeneration of implants are being discovered everyday by scientists, engineers, and surgeons. Our objective in this study is to combine polylactic acid which is a polymer with hydroxyapatite in the repairment of bone defects considering the increased need by medical application fields. Materials and methods: After 750 g of PLA with a diameter of 2.85 mm was granulated into minimum particles, these particles were homogenously mixed with hydroxyapatite prepared in laboratory environment. Using this mixture, HA-PLA filament with a diameter of 2.85 mm was prepared in the extrusion device in Kütahya Medical Sciences University Innovative Technology Laboratory. The temperature was 250 °C and the gearmotor speed was 9 rpm during extrusion. X-ray diffraction (XRD) analysis was made for crystal phase analyses of the produced hydroxyapatite powder, to determine the produced main phase and examine whether a minor phase occurred. Vickers microhardness test was applied on both samples to measure the endurance levels of the samples prepared with HA-PLA filament. A loading force of 10 kg was applied on the samples for 10 s. Results: Hydroxyapatite peaks in XRD spectrum of the sample presented in figures are concordant with Joint Committee on Powder Diffraction Standards, JCPDS - File Card No. 01-075-9526 and no significant minor phase was observed. For both samples, hardness value was observed to increase between 3 and 5 mm. Conclusion: Surfacing hydroxyapatite on metallic materials is possible. By similar logic, to increase durability with low cost, characteristics of biomaterials can be improved with combinations such as hydroxyapatite PLA. Thus, we found that while these materials have usage limitations due to present disadvantages when used alone, it is possible to increase their efficiency and availability through different combinations.

A very easy technique of stenting for laparoscopic pyeloplasty: penbegul intravenous cannula (PICA) technique.

INTRODUCTION: Double-J stent insertion during laparoscopic pyeloplasty is a difficult and time-consuming process and several techniques were defined to perform a double-J stent with an antegrade approach. In this study we present the technique (PICA) of antegrade double-J placement during laparoscopic pyeloplasty by using 14 gauge intravenous cannula. Surgical technique: After we complete the suturing of the posterior wall of the anastomosis during laparoscopic pyeloplasty, we first puncture the abdominal wall with a 14-gauge "intravenous cannula" from a location that provides most suitable angle for inserting the double-J stent into the ureter. We remove the metal needle of the cannula, and the sheath which has an inner diameter of 5.2F remains over the abdominal wall. The double J stent is then advanced from inside the cannula sheath to the intraperitoneal area; under laparoscopic imaging the stent is gently grasped at its distal end using an atraumatic laparoscopic forceps to insert it into the ureter. The stent is then pulled down to its proximal end, and after the guidewire is removed, the proximal end of the double-J stent is placed inside the renal pelvis with an atraumatic forceps. With this technique we can apply the double-J stent in just one step. Additionaly we can use a 14-gauge IV cannula sheath as a trocar when needed during laparoscopic pyeloplasty to retract an organ or reveal an anastomosis line. COMMENTS: Our new technique of antegrade double-J placement during laparoscopic pyeloplasty by 14 gauge intravenous cannula sheath, is very easy and quick to perform.

A very easy technique of stenting for laparoscopic pyeloplasty: penbegul intravenous cannula (PICA) technique

ABSTRACT Introduction: Double-J stent insertion during laparoscopic pyeloplasty is a difficult and time-consuming process and several techniques were defined to perform a double-J stent with an antegrade approach. In this study we present the technique (PICA) of antegrade double-J placement during laparoscopic pyeloplasty by using 14 gauge intravenous cannula. Surgıcal technıque: After we complete the suturing of the posterior wall of the anastomosis during laparoscopic pyeloplasty, we first puncture the abdominal wall with a 14-gauge "intravenous cannula" from a location that provides most suitable angle for inserting the double-J stent into the ureter. We remove the metal needle of the cannula, and the sheath which has an inner diameter of 5.2F remains over the abdominal wall. The double J stent is then advanced from inside the cannula sheath to the intraperitoneal area; under laparoscopic imaging the stent is gently grasped at its distal end using an atraumatic laparoscopic forceps to insert it into the ureter. The stent is then pulled down to its proximal end, and after the guidewire is removed, the proximal end of the double-J stent is placed inside the renal pelvis with an atraumatic forceps. With this technique we can apply the double-J stent in just one step. Additionaly we can use a 14-gauge IV cannula sheath as a trocar when needed during laparoscopic pyeloplasty to retract an organ or reveal an anastomosis line. Comments: Our new technique of antegrade double-J placement during laparoscopic pyeloplasty by 14 gauge intravenous cannula sheath, is very easy and quick to perform.