22G Needle Research Articles

Positive Pressure and Negative Pressure Irrigation Dynamics with Different Needle Designs Using Computational Fluid Dynamics

This study aimed to investigate the irrigation dynamics of the positive pressure side-vented (SV) needle, EndoVac (micropores) needle and modified apical negative pressure (mANP) open-ended needle using computational fluid dynamics (CFD). A simulation of a prepared root canal (conical frustum) of 15 mm length with an apical diameter of 0.40 mm following Protaper F4 apical preparation was created using three-dimensional (3D) CAD software. The 3D simulated needle of SV 30G needle, EndoVac with micropores needle and mANP, 30G flat open-ended needle were also created. The irrigation dynamics were evaluated through transient CFD simulations. In addition, the irrigation dynamics of mANP at 0.2 mm, 0.5 mm, and 1.0 mm short from the working length were also assessed. The EndoVac and mANP showed negative apical static pressure and streamline patterns able to reach the apical region, thus indicating negligible extrusion. Meanwhile, SV showed positive apical static pressure and almost nonexistent streamlines beyond the needle tip. The SV showed the highest wall shear stress (WSS) magnitude of 1030Pa whereas Endovac (161 Pa) and mANP1 (258 Pa). However, SV revealed lower average WSS (10 Pa) compared to mANP1 (13 Pa) and mANP2 (11 Pa). This is due to SV developed a localised maximum WSS opposite the open vent area only therefore, uneven distribution of WSS. The EndoVac system developed a localised maximum WSS in the pair of micropores furthest away from the apical. CFD analysis of the EndoVac, mANP and SV showed different technique approach, needle design and needle depths insertion affect the irrigation dynamics pattern and magnitude.

Does needle size matter? Effects of micro-hypodermic needle injections of botulinum toxin type A in patients with hemifacial spasm

IntroductionBotulinum toxin type A (BoNT/A) injections are the first-line treatment for primary hemifacial spasms (HFS), but require frequent painful injections. Although micro-hypodermic needles are commonly used for aesthetic BoNT/A injections to lessen pain and bruising, their benefits in HFS remain unclear. ObjectiveTo compare side effects of BoNT/A injection, specifically pain and bruising, between primary HFS patients who received injections using micro-hypodermic needles (34-G) and those using standard needles (30-G). MethodsThis cross-over, double-blind, randomised controlled trial involved HFS patients who received BoNT/A injections using either a 34-G or 30-G needle at two visits 12 weeks apart. Primary outcomes, pain and bruising were assessed immediately after injection using the Visual Analogue Scale (VAS) and Short-form McGill Pain Questionnaire (Thai version, SF-MPQ). Bruise assessment was also conducted one week after each injection. Secondary outcomes involved comparing efficacy of BoNT/A between the two types of needles and assessing other complications beyond pain and bruising. Results65 HFS patients (47 women and 18 men; mean age 59.46 ± 11.48 years; mean disease duration 5.86 ± 4.16 years) were included in the study. Patients who received 34-G needle injections reported significantly reduced pain, as indicated by VAS, total SF-MPQ scores, and bruise scores, compared to those who received 30-G needle injections (p < 0.001, each). There were no differences in efficacy or occurrence of other complications associated with BoNT/A between the two needle types. ConclusionIn HFS patients, BoNT/A injections using micro-hypodermic needles resulted in reduced pain and bruising, compared to standard needles, while maintaining similar BoNT/A benefits.

Needle-tract seeding following endoscopic ultrasound-guided fine-needle aspiration using a 25G needle for pancreatic tail cancer.

Needle-tract seeding following endoscopic ultrasound-guided fine-needle aspiration using a 25G needle for pancreatic tail cancer.

The safety and efficacy of endoscopic ultrasound-guided portal pressure gradient measurement with concomitant endoscopic ultrasound-guided liver biopsy: a systematic review

IntroductionPortal hypertension (PH) is a complication of advanced liver disease. Traditionally, PH has been quantified using hepatic venous pressure gradient (HVPG) through an indirect transjugular approach requiring ionizing radiation exposure. Endoscopic ultrasound-guided porto-systemic pressure gradient (EUS-PPG) measurement is an emerging alternative, minimally invasive technique that provides direct portal pressure measurement. The aim of this systematic review is to evaluate the safety and efficacy of EUS-PPG measurement and concomitant EUS-guided liver biopsy (EUS-LB) in patients with chronic liver disease.MethodsThe preferred reporting items for systematic reviews and meta-analyses method was used. A PubMed, Medline, Web of Science, Google Scholar, and CINAHL search for terms “endoscopic ultrasound,” “EUS,” and “portal pressure gradient” was used to identify qualifying studies. Eligible studies included those which were published before 2022, reporting outcomes of EUS-PPG measurement, simultaneous EUS-LB if applicable, and adverse events rate. Risk of bias was assessed by Egger’s test. Results were synthesized using I2 to test heterogeneity.ResultsFour published studies including 147 patients met inclusion criteria, with mean age 59.6 years, 59% male. Indications for EUS-PPG measurement were history of chronic liver disease or suspected cirrhosis, viral hepatitis, alcohol associated liver disease, hepatic sinusoidal obstruction or Budd Chiari syndrome. The pooled technical success rate of EUS-PPG measurements was 98.61% with 95% confidence interval of 95.20% - 99.82%. A 25-gauge needle was used in 92% (135/147) of patients. EUS-PPG measurement was performed through a transgastric approach in all 147 (100%) patients using a compact manometer with pressure transducer and non-compressible tubing. The mean PPG was 10.07 (range 6.44 – 13.70) mmHg. Ninety-five patients underwent simultaneous EUS-LB using 19G needle with wet suction technique. Technical success rate of EUS-LB was 100% and specimen was adequate in 99% (94/95) patients to establish histological diagnosis. There were no major life-threatening complications of the EUS-PPG procedure. Predominant adverse events were abdominal pain 6.1% (9/147) and sore throat 5.4% (8/147).ConclusionEUS-PPG measurement is safe and useful in providing an assessment of portal pressure in patients with chronic liver disease. Future studies are needed to evaluate whether there is consistent correlation between EUS-PPG measurements and histologic fibrosis stage by liver biopsy.

EARLY-STAGE SELF-ASSEMBLING PEPTIDE HYDROGEL-BASED INTERVENTION FOR ARTICULAR PATELLA CARTILAGE REPAIR

AbstractObjectivesThe aim of this study was to develop an in vitro GAG-depleted patella model and assess the biomechanical effects following treatment with a SAP:CS self-assembling hydrogel.MethodsPorcine patellae (4–6 month old) were harvested and subject to 0.1% (w/v) sodium dodecyl sulfate (SDS) washes to remove GAGs from the cartilage. Patellae were GAG depleted and then treated by injection with SAP (∼ 6 mM) and CS (10 mg) in Ringer's solution through a 30G needle. Native, GAG depleted and SAP:CS treated patellae were tested through static indentation testing, using 15g load, 5mm indenter over 1hr period. The degree of deformation of each group was assessed and compared (Mann-Whitney, p&lt;0.05). Native, GAG depleted, sham (saline only) and SAP:CS treated paired patellae and femurs were additionally characterized tribologically through sequential wear testing when undergoing a walking gait profile (n=6 per group). The cartilage surfaces were assessed and compared (Mann-Whitney, p&lt;0.05) using the ICRS scoring system, surface damage was illustrated through the application of Indian ink.ResultsStatic indentation tests indicated significant increase in indentation deformation of GAG depleted group compared to native group (n=6, p&lt;0.01) and significant reduction in deformation of SAP:CS treated group compared to GAG depleted group (n=6, p&lt;0.05). Sequential wear tests indicated a significant increase in the cartilage damage on the both surfaces of the patellofemoral joint in the GAG depleted group, compared to the native group (n=6, p&lt;0.001), Following SAP:CS treatment, significant protection from damage was observed on femoral surface (n=6, p&lt;0.005), with some non-significant reduction in damage on the patella surface. Sham injections showed no significant increase in damage compared to the native and treated samples.ConclusionsThe ∼50% reduction of GAGs represented a moderate osteoarthritic patella cartilage model. This same loss transferred to the dynamic wear tests with significant changes in the damage on the femoral counter face associated with the GAG loss. SAP:CS treatment showed promise in restoring cartilage stiffness to treat Chondromalacia patella in static indentation tests. Sequential wear tests showed that the SAP:CS treatment protects the cartilage layer of both surfaces in the patellofemoral joint from damage in an extreme degeneration model. The sham injections showed that injecting cartilage with a 30G and saline does not cause any significant damage to the cartilage layer.Declaration of Interest(a) fully declare any financial or other potential conflict of interest

Optimized total RNA isolation from bovine sperm with enhanced sperm head lysis.

Increasing evidence of sperm RNA's role in fertilization and embryonic development has provided impetus for its isolation and thorough characterization. Sperm are considered tough-to-lyse cells due to the compact condensed DNA in sperm heads. Lack of consensus among bovine sperm RNA isolation protocols introduces experimental variability in transcriptome studies. Here, we describe an optimized method for total RNA isolation from bovine sperm using the TRIzol reagent. This study critically investigated the effects of various lysis conditions on sperm RNA isolation. Sperm suspended in TRIzol were subjected to a combination of mechanical treatments (sonication and passage through a 30G needle and syringe) and chemical treatments (supplementation with reducing agents 1,4-dithiothreitol and tris(2-carboxyethyl) phosphine hydrochloride (TCEP)). Microscopic evaluation of sperm lysis confirmed preferential sperm tail versus sperm head lysis. Interestingly, only TCEP-supplemented TRIzol (both mechanical treatments) had progressive sperm head lysis and consistently yielded total sperm RNA. Furthermore, RNA integrity was confirmed based on the electrophoresis profile and an absence of genomic DNA and somatic cells (e.g., epithelial cells, spermatids, etc.) with RT-qPCR. Our findings highlighted the importance of sperm lysis, specifically of the sperm head using TCEP with mechanical treatment, in total RNA isolation and presented a bovine-specific sperm RNA isolation method to reduce experimental variabilities.

The Effect of Some Different Blood Anticoagulants on Rabbits Plasma Biochemical Parameters under Different Temperatures

The aim of present study was to compare the effect of Ca chelating anticoagulants (EDTA, citrate and oxalate) and antithrombin anticoagulant (heparin) on some rabbits plasma biochemical parameters at room temperature 25℃ and extreme temperatures -18℃and 50℃ for 1hr. Five male rabbits weighting between 800-1000gm, kept in the animal house /College of Veterinary Medicine/University of Diyala, under 12:12 dark light cycle with ad libtum food and water in individual cages (60cm,40cm) during November and December /2022. Four ml of blood samples were collected by cardiac puncture (23G needle) into four tubes contain anticoagulants: (EDTA, citrate, oxalate and heparin)one ml of blood for each tube; then the blood samples were kept at :room temperature 25℃, waterbath50℃ and refrigerator -18 ℃, for 1hr then put in centrifuge at 3000rpm for 15min. From total examined blood samples =24 for each Ca chelating anticoagulants (EDTA, citrate and oxalate) and antithrombin anticoagulant (heparin) after 1hr under in 25c℃ , -18℃ and 50℃. The both groups of anticoagulants (Ca chelating and antithrombin) showed no significant differences P&gt;0.05 between them in level of biochemical parameters (glucose, total protein, cholesterol and urea) after 1 hr at 25C; on the other hand significant increase in plasma glucose, total protein and cholesterol beside significant decrease in plasma urea of Ca chelating anticoagulants after 1hr at -18C and 50C as compare with antithrombin anticoagulant. In conclusion; heparin was more effective than Ca chelating anticoagulant in preserve plasma biochemical parameters within normal values under extreme cool and hot condition.

Mechanical crosstalk between the intervertebral disc, facet joints, and vertebral endplate following acute disc injury in a rabbit model.

Vertebral endplate sclerosis and facet osteoarthritis have been documented in animals and humans. However, it is unclear how these adjacent pathologies engage in crosstalk with the intervertebral disc. This study sought to elucidate this crosstalk by assessing each compartment individually in response to acute disc injury. Eleven New Zealand White rabbits underwent annular disc puncture using a 16G or 21G needle. At 4 and 10 weeks, individual compartments of the motion segment were analyzed. Discs underwent T 1 relaxation mapping with MRI contrast agent gadodiamide as well T 2 mapping. Both discs and facets underwent mechanical testing via vertebra-disc-vertebra tension-compression creep testing and indentation testing, respectively. Endplate bone density was quantified via μCT. Discs and facets were sectioned and stained for histology scoring. Intervertebral discs became more degenerative with increasing needle diameter and time post-puncture. Bone density also increased in endplates adjacent to both 21G and 16G punctured discs leading to reduced gadodiamide transport at 10 weeks. The facet joints, however, did not follow this same trend. Facets adjacent to 16G punctured discs were less degenerative than facets adjacent to 21G punctured discs at 10 weeks. 16G facets were more degenerative at 4 weeks than at 10, suggesting the cartilage had recovered. The formation of severe disc osteophytes in 16G punctured discs between 4 and 10 weeks likely offloaded the facet cartilage, leading to the recovery observed. Overall, this study supports that degeneration spans the whole spinal motion segment following disc injury. Vertebral endplate thickening occurred in response to disc injury, which limited the diffusion of small molecules into the disc. This work also suggests that altered disc mechanics can induce facet degeneration, and that extreme bony remodeling adjacent to the disc may promote facet cartilage recovery through offloading of the articular cartilage.

Inhibition of retinal ischemia-reperfusion injury in rats by inhalation of low-concentration hydrogen gas.

To investigate the inhibitory effect of hydrogen gas inhalation on retinal ischemia reperfusion (I/R) injury using a rat model. Six-week-old male Sprague-Dawley rats were used. A 27G needle connected by a tube to a saline bottle placed 200cm above the eye was inserted into the anterior eye chamber to create a rat retinal I/R model. In the ischemia-plus-hydrogen-gas group (H2( +) group), the ischemia time was set to 90min, and 1.8% hydrogen was added to the air delivered by the anesthesia mask simultaneously with the start of ischemia. In the non-hydrogen-treatment ischemia group (H2( -) group), I/R injury was created similarly, but only air was inhaled. ERGs were measured; after removal of the eyes, the retina was examined for histological, immunostaining, and molecular biological analyses. The mean thickness of the inner retinal layer in the H2( +) group was 107.2 ± 16.0μm (n = 5), significantly greater than that in the H2( -) group (60.8 ± 6.7μm). Immunostaining for Iba1 in the H2( -) group showed increased numbers of microglia and microglial infiltration into the subretinal space, while there was no increase in microglia in the H2( +) group. B-wave amplitudes in the H2( +) group were significantly higher than in the H2( -) group. In the membrane antibody array, levels of interleukin-6, monocyte chemotactic protein 1, and tumor necrosis factor alpha were significantly lower in the H2( +) group than in the H2( -) group. Inhalation of 1.8% hydrogen gas inhibited the induction of inflammation, morphological/structural changes, and glial cell increase caused by retinal I/R injury.

Clinical outcomes of 3T magnetic resonance imaging-guided lumbar and sacral foraminal injections

PurposeThis article evaluates the feasibility, safety, and efficacy of MRI-guided lumbar or sacral nerve root infiltration for chronic back pain. We compared the outcomes of our MRI-guided infiltrations with data from CT-guided infiltrations reported in the literature and explored the potential advantages of MRI guidance.MethodForty-eight MRI-guided nerve root infiltrations were performed using a 3 T MRI machine. The optimal needle path was determined using breathhold T2-weighted sequences, and the needle was advanced under interleaved guidance based on breathhold PD-weighted images. Pain levels were assessed using a numeric rating scale (NRS) before the procedure and up to 5 months after, during follow-up. Procedure success was evaluated by comparing patients’ pain levels before and after the infiltration.ResultsThe MRI-guided infiltrations yielded pain reduction 1 week after the infiltration in 92% of cases, with an average NRS substantial change of 3.9 points. Pain reduction persisted after 5 months for 51% of procedures. No procedure-related complications occurred. The use of a 22G needle and reconstructed subtraction images from T2 FatSat sequences improved the workflow.ConclusionOur study showed that MRI-guided nerve root infiltration is a feasible, safe, and effective treatment option for chronic back pain. Precise positioning of the needle tip and accurate distribution of the injected solution contributed to the effectiveness of MRI-guided infiltration, which appeared to be as accurate as CT-guided procedures. Further research is needed to explore the potential benefits of metal artifact reduction sequences to optimize chronic back pain management.

Focused ultrasound as an alternative to dry needling for the treatment of tendinopathies: A murine model.

Tendinopathies account for 30% of 102 million annual musculoskeletal injuries occurring annually in the United States. Current treatments, like dry needling, induce microdamage to promote healing but produce mixed success rates. Previously, we showed focused ultrasound can noninvasively create microdamage while preserving mechanical properties in ex vivo murine tendons. This present study compared growth factor, histological, and mechanical effects after focused ultrasound or dry needling treatments in an in vivo murine tendon injury model. Partial Achilles tenotomy was performed in 26 rats. One-week postsurgery, tendons were treated with focused ultrasound (1.5 MHz, 1-ms pulses at 10 Hz for 106 s, p+ = 49 MPa, p- = 19 MPa) or dry needling (30 G needle, 5 fenestrations over 20 s) and survived for 1 additional week. Blood was collected immediately before and after treatment and before euthanasia; plasma was assayed for growth factors. Treated tendons and contralateral controls were harvested for histology or mechanical testing. No differences were found between treatments in release of insulin growth factor 1 and transforming growth factor beta; vascular endothelial growth factor A concentrations were too low for detection. Histologically, focused ultrasound and dry needling tendons displayed localized fibroblast infiltration without collagen proliferation with no detectable differences between treatments. Mechanically, stiffness and percent relaxation of dry needling tendons were lower than controls (p = 0.0041, p = 0.0441, respectively), whereas stiffness and percent relaxation of focused ultrasound tendons were not different from controls. These results suggest focused ultrasound should be studied further to determine how this modality can be leveraged as a therapy for tendinopathies.

Novel Technique for 27-Gauge Forceps-Assisted Transscleral Refixation of the Dislocated CZ70BD Intraocular Lens.

To report a novel technique for refixation of the dislocated CZ70BD intraocular lens. Posterior vitrectomy is performed with a 23-gauge or 25-gauge pars plana vitrectomy system with chandelier illumination. One needle of a double-arm 9-0 prolene needle is passed through the sclera 1.5 mm postlimbus. The needle is retrieved through the corneal paracentesis using a 27-G needle, and the suture is then cut. The suture end is passed through the eyelet of the dislocated CZ70BD intraocular lens inside the vitreous cavity. This is aided with a pair of 27-G MaxGrip forceps, which is inserted through a 27-G sclerostomy site at the intended scleral outlet. After passing the suture through the eyelet, the suture is pulled out at the 27-G sclerostomy site and a knot is tied and rotated. Similar procedure is performed for the second haptic if necessary. Seven eyes were successfully operated on using this technique with a mean follow-up of 12.4 months. There was significant improvement in the best-corrected visual acuity after the operation ( P = 0.016). Postoperative intraocular lens centration and alignment were satisfactory. One patient developed macula-on retinal detachment 1 month after the operation, which was successfully repaired without loss in the best-corrected visual acuity. The described novel technique is effective for refixation of dislocated CZ70BD intraocular lens.

Case Report: Yamane Fixation of a Light Adjustable Lens in a Patient with Marfan Syndrome

This paper aims to discuss a case of a Light Adjustable Lens (LAL) implanted with the Yamane technique in a Marfan patient undergoing complex cataract surgery. A 60-year-old female with a history of Marfan syndrome presented in May 2020 with complaint of worsening vision due to bilateral subluxed cataracts. Bilateral LALs were planned to be implanted in the capsular bag with scleral fixated Ahmed segments using 5-0 prolene due to zonular instability. The procedure was complicated by an anterior capsular tear at 6 O’clock due to a very friable capsular bag. This tear extended posteriorly with no vitreous loss. Given inadequate capsular support, the decision was then made to scleral fixate the LAL using a Yamane technique. The first attempt at scleral fixation resulted in the LAL haptic breaking off into the 27G needle during the scleral pass. The LAL with remaining haptic was cut in half and explanted. A new LAL was successfully fixated with the Yamane technique. A scleral fixated Ahmed segments using 5-0 prolene was done successfully for the right eye. Final adjustment and locking occurred 10 weeks after right eye procedure. The final refraction of the right eye was measured to be plano, + 0.5 cyl, 85 axis with uncorrected distance visual acuity of 20/20 and corrected distance visual acuity of 20/20. The final refraction of the left eye was measured to be -2.75 D, 0 cyl, 0 axis with uncorrected distance visual acuity of 20/200, uncorrected near visual acuity of J1+ and corrected distance visual acuity of 20/20. When choosing a lens to Yamane, LALs are uniquely capable of correcting a residual refractive error without an additional surgery. LALs are an excellent option for patients that desire a refractive outcome with limited or no capsular support.

Investigation of the Effect of Needle Diameter and the Solution Flow Rate on Fiber Morphology in the Electrospinning Method

Abstract In the study, the morphological properties of polyacrylonitrile (PAN) fibers produced by electrospinning at different needle diameters and solution flow rates were investigated. For this purpose, 20G and 22G diameter needles were used. The fibres were produced at flow rates of 0.5 ml/hr, 1 ml/hr and 1.5 ml/hr. Scanning electron microscopy (SEM) was used to measure nanofiber diameters. Statistical analyzes were made with the help of the SPSS program. It was observed that finer fibers were obtained as the needle diameter decreased. As the solution flow rate increased, thicker fibers were obtained. In addition, it was observed that the needle diameter and flow rate affect the fiber arrangement and interfiber spacing.

The type of suture material affects transverse aortic constriction-induced heart failure development in mice: a repeated measures correlation analysis.

Transverse-aortic constriction (TAC) operation is a widely used animal model to induce hypertrophy and heart failure through left-ventricular pressure overload. In mice, the cardiac response to TAC exhibits considerable variability influenced by factors such as strain, sub-strain, age, sex and vendor. To investigate the impact of suture material (silk versus prolene) and size (6-0 versus 7-0) on the TAC-induced phenotype, we performed surgeries on male C57BL6/N mice at 9 weeks of age defining the aortic constriction by a 27G needle, thereby employing most frequently used methodological settings. The mice were randomly assigned into four separate groups, 6-0 silk, 7-0 silk, 6-0 prolene and 7-0 prolene (10 mice per group). Echocardiography was conducted before TAC and every 4 weeks thereafter to monitor the development of heart failure. Repeated measures correlation analysis was employed to compare disease progression among the different groups. Our findings reveal a significant influence of the chosen suture material on TAC outcomes. Mice operated with prolene showed increased mortality, slower body weight gain, faster left-ventricular mass increase, and a faster decline in left-ventricular ejection fraction, fractional shortening and aortic pressure gradient compared to silk-operated mice. Moreover, despite non significant, using thinner suture threads (7-0) tended to result in a more severe phenotype compared to thicker threads (6-0) across all tested parameters. Collectively, our results highlight the importance of suture material selection in determining the cardiac phenotype induced by TAC and emphasize the need to consider this factor when comparing data across different research laboratories.

Is constant needle motion during soft tissue filler injections a safer procedure? A theoretical mathematical model for evaluating patient safety.

The safety rationale behind the constant needle motion injection technique is based on the assumption that due to the constant needle motion and simultaneous soft tissue filler material administration a smaller amount of product per area may be injected into an artery if an artery within the range of the moving needle is inadvertently entered. To perform mathematical calculations for determining the probability for causing intra-arterial product administration when constantly moving the needle during facial aesthetic soft tissue filler injections. This study was designed as a theoretical investigation into the probabilities for causing adverse events due to intravascular injection of soft tissue filler material when constantly moving a 27-G needle during facial soft tissue filler administration. It was revealed that with a higher number of conducted injection passes a greater soft tissue area can be covered by the needle. The odds of encountering an artery within the covered soft tissue volume and the odds of injecting any volume greater than zero into the arterial blood stream increases with the number of performed injection passes. This increase is greatest between 1 and 10 performed injection passes. This model demonstrates that the constant needle motion technique increases the probability of encountering an artery within the treatment area and thus increases the odds for intra-arterial product administration. The constant needle motion technique does not increase safety but rather may increase the odds of causing intra-arterial product administration with the respective adverse consequences for the patient.

Diagnostic Accuracy and Safety Between two Needle Sizes in Percutaneous Trans-Thoracic Biopsy for the Evaluation of Pulmonary Lesions.

Percutaneous trans-thoracic lung biopsy has a crucial role in diagnosing lung lesions including lung cancer. However, there is no clear guideline regarding the needle size in percutaneous trans-thoracic lung biopsy. This study aims to evaluate the diagnostic accuracy and complication rate between two needle sizes for percutaneous trans-thoracic lung biopsy. A retrospective review of patients with lung lesions who underwent percutaneous trans-thoracic lung biopsy between November 2010 and December 2019 was performed. The demographic data, imaging finding, biopsy technique, complication and histologic outcome were recorded and analyzed. Propensity score matching was done to reduce bias in baseline characteristics. Of 377 patients who underwent percutaneous trans-thoracic lung biopsy, 331 patients had complete information. The patients were divided in two groups, comprising of 153 patients in 18G needle group and 178 patients in 20G needle group. After propensity score matching, there were 126 patients left in each group. The diagnostic accuracy, sensitivity, specificity, positive predictive value and negative predictive value for 18G needle group were 92.9%, 98.1%, 65.0%, 93.7% and 86.7%, respectively. For 20G needle group, the diagnostic accuracy, sensitivity, specificity, predictive value and negative predictive value were 96.0%, 99.0%, 83.3%, 96.2% and 95.2%, respectively. The immediate complication rate was 35.7% and 31.7% in 18G and 20 G needle groups (p= 0.505), respectively. There was no difference in diagnostic accuracy and immediate complication rates between 18G and 20G needle use for percutaneous trans-thoracic lung biopsy.

An Experimental Model Exhibiting Anterograde and Retrograde Vascular Occlusion of Facial Fillers to Avoid Vision Loss.

Facial filler injection techniques that help decrease the risk of vascular occlusion are an important growing area of study. This study demonstrates a model of injecting fillers into a simulated bifurcated arterial system, using different sized needle gauges at a constant injection pressure. Three facial fillers were injected into a bifurcated intravenous tubing with continuous irrigation at a constant pressure to simulate a vascular system. Videography was used to observe for retrograde flow through the simulated supratrochlear artery to the bifurcation point, where the filler was redirected by anterograde flow into the branch representing the ophthalmic artery. Filler injection with retrograde flow to the bifurcation occurred with all the 27G needle trials. In comparison, the 30G needle trials were only able to reach the bifurcation point in three of the nine trials. The average time to the bifurcation point with subsequent ophthalmic artery anterograde flow with the 27G and 30G needles were 8.44 (95% confidence interval ±2.06) and 33.33 (95% confidence interval ±16.56) seconds, respectively. Larger 27G needles consistently reached retrograde flow and the bifurcation point faster than 30G needles. This study suggests thinner needles may be less likely to cause retrograde occlusion.

A phase IB/IIA study of ex vivo expanded allogeneic bone marrow–derived mesenchymal stem cells for the treatment of rectovaginal fistulizing Crohn’s disease

BackgroundCrohn-related rectovaginal fistulas are notoriously difficult to treat. Studies of mesenchymal stem cells for the treatment of perianal Crohn fistulizing disease have largely excluded rectovaginal fistulas. The aim of this study was to determine the safety and efficacy of mesenchymal stem cells for refractory rectovaginal fistulizing Crohn disease. MethodsA phase IB/IIA randomized control trial was performed in a 3:1, single-blinded study. Patients included were adult women with an anovaginal/rectovaginal fistula in the setting of Crohn disease. Seventy-five million mesenchymal stem cells were administered with a 22G needle after curettage and primary closure of the fistula tract at day 0 and month 3. Adverse and serious adverse events were recorded at post-procedure day 1, week 2, week 6, month 3, month 6, and month 12, along with clinical healing, magnetic resonance imaging, and patient-reported outcomes. ResultsA total of 19 patients were enrolled and treated—15 treatment and 4 control. There were no adverse or serious adverse events related to mesenchymal stem cell therapy. At 6 months, 50% of the treatment group and 0% of the control had complete clinical and radiographic healing; 91.7% of the treatment group had improvement at 6 months with only one patient having a lack of response, whereas only 50% of the control group had improvement at 6 months. ConclusionBone marrow-derived mesenchymal stem cells offer a safe alternative treatment approach for rectovaginal fistulas in the setting of Crohn disease. Complete healing was achieved in half of the patients.

Injectable gelatin/glucosamine cryogel microbeads as scaffolds for chondrocyte delivery in cartilage tissue engineering

In this study, we fabricate squeezable cryogel microbeads as injectable scaffolds for minimum invasive delivery of chondrocytes for cartilage tissue engineering applications. The microbeads with different glucosamine concentrations were prepared by combining the water-in-oil emulsion and cryogelation through crosslinking of gelatin with glutaraldehyde in the presence of glucosamine. The physicochemical characterization results show the successful preparation of cryogel microbeads with uniform shape and size, high porosity, large pore size, high water uptake capacity, and good injectability. In vitro analysis indicates proliferation, migration, and differentiated phenotype of rabbit chondrocytes in the cryogel scaffolds. The seeded chondrocytes in the cryogel scaffold can be delivered by injecting through an 18G needle to fully retain the cell viability. Furthermore, the incorporation of glucosamine in the cryogel promoted the differentiated phenotype of chondrocytes in a dose-dependent manner, from cartilage-specific gene expression and protein production. The in vivo study by injecting the cryogel microbeads into the subcutaneous pockets of nude mice indicates good retention ability as well as good biocompatibility and suitable biodegradability of the cryogel scaffold. Furthermore, the injected chondrocyte/cryogel microbead constructs can form ectopic functional neocartilage tissues following subcutaneous implantation in 21 days, as evidenced by histological and immunohistochemical analysis.