Nylon Suture Research Articles

Relative Motion Flexion Splinting for Flexor Tendon Lacerations: Proof of Concept.

The principle of relative motion has allowed patients to regain a higher degree of hand function, while protecting extensor tendon repairs. The purpose of this study was to determine whether the principle of relative motion could be a viable method to protect a flexor tendon repair. Four fresh-frozen cadaver arms were each mounted on a testing apparatus (wrist in 30° of extension, metacarpophalangeal [MCP] joints blocked to 70°-80°). A minimum of 11 N was used to cyclically load the flexor digitorum profundus and extensor digitorum communis tendons to maximum allowable flexion and extension for 25 cycles. Measurements of elongation of the tendons were obtained through the use of differential variable reluctance transducers. Testing was performed in both intact and repaired (single 6-0 nylon suture) middle finger tendons (zone 3) with and without a relative motion flexion splint (RMFS), which placed the affected finger in 15° to 25° of relative flexion at the MCP joint. In all 4 hands, elongation was restricted to less than 1.3 mm in repaired tendon in the RMFS compared with elongation >2 mm in the nonsplinted condition. Average elongation was 0.86 mm (SD = 0.45). Visual examination of the tendons demonstrated no gapping with the use of the RMFS in any of the hands. All repairs had suture breakage and repair rupture without the RMFS. This study demonstrates that the RMFS decreases elongation and eliminates tendon-repair gapping after flexion/extension cycling in a cadaver model. It provides proof of concept that the RMFS may be a viable protective mechanism for flexor tendon repairs in zone 3.

Releasable Single Suture for Primary Pterygium Excision With a Conjunctival Autograft

To evaluate the efficacy of a releasable single suture for pterygium excision with a conjunctival autograft (CAG). Retrospective case series at a tertiary eye care center in central India was conducted. Medical records of 150 patients, who underwent primary pterygium excision with a CAG secured by a single releasable 10-0 nylon suture in the last year were reviewed. The surgical duration was noted. The suture was released on the first postoperative day under topical anesthesia. Patients were followed up until 1 year. At each visit, factors studied were patient comfort [pain grading on a visual analog scale], graft apposition, complications, and recurrence. Mean age of patients was 39 ± 11 years. Most patients in our study were female (58.7%). Sixty percent of pterygia were of Tan grade 2. The mean duration of surgery was 4.8 ± 1.3 minutes. The maximum size of the CAG was 6 mm (3-6 mm). The graft retraction rate was 5.3% (1 mm retraction in the CAG more than 5.5 mm) with no event of graft loss. Four percent of patients had grade 1 recurrence. Releasable single suture may offer a good and simple alternative, which uses the gold standard technique of the CAG with exclusion of suture-related complications.

Photochemical Cross-Linking for Penetrating Corneal Wound Closure in Enucleated Porcine Eyes

ABSTRACTPurpose: To compare the efficacy of photochemical-induced tissue cross-linking (PCL), utilizing Rose Bengal (RB) and 532 nm green light irradiation (RB-PCL), with standard sutures for closure of penetrating corneal incision in porcine cadaver eyes.Methods: A full-thickness penetrating incision, 3 mm in length parallel to the limbus and perpendicular to the corneal surface, was made in the enucleated porcine cornea. Photochemical cross-linking was performed with tropical RB application and irradiation of 532 nm green light (0.6 W/cm2) for 200, 250, and 300 seconds at laser fluences of 120, 150, and 180 J/cm2, respectively, which was compared with the standard 10-0 nylon suture group. Following treatment, intraocular pressure to the point where wound leakage occurred (IOPL) was measured. Corneal central thickness and surface temperature before and after PCL treatment were recorded. Optical coherence tomography (OCT) and scanning electron microscopy (SEM) were utilized to evaluate wound closure.Results: The mean corneal central thickness was increased from 812.0 ± 47.0 to 838.0 ± 45.6 µm after the incision as a result of cornea aqueous humor infiltration. RB penetrated approximately 140 μm into the porcine corneal stroma. The mean IOPL for untreated blank group after incision was 4.27 ± 0.36 mmHg. Increased laser fluences produced increased IOPL of 27.02 ± 3.01 (PCL120), 31.60 ± 3.67 (PCL150) and 36.73 ± 3.25 mmHg (PCL180), which were statistically different from the control intact group. The mean IOPL in the sutured cornea was 57.30 ± 4.59 mmHg. The average surface temperature difference before and after PCL treatment was 2.03 ± 0.45–2.47 ± 0.79°C. OCT demonstrated not only complete but also improved closure in comparison with disorganized collagen fibers after conventional suturing, which is further confirmed by SEM.Conclusions: Complete and clinically relevant seal of full-thickness porcine corneal incision was achieved using PCL method ex vivo, which provides potential application of this technique in ocular wound closure.

Effects of PDGF-BB delivery from heparinized collagen sutures on the healing of lacerated chicken flexor tendon in vivo.

A high strength aligned collagen suture was fabricated via linear electrocompaction and heparinized for prolonged delivery of PDFG-BB. When it was used to suture a complete lacerated flexor tendon in a chicken model controlled release of the PDGF-BB improved the strength of treated tendon after 12 weeks compared to tendon sutured with commercial nylon suture. Furthermore, Collagen suture with affinity bound PDGF-BB enhanced the vascularization and remodeling of lacerated tendon when it compare to synthetic nylon suture. Overall, electrocompacted collagen sutures holds potential to improve repair outcome in flexor tendon surgeries by improving repair strength and stiffness, vascularity, and remodeling via sustained delivery of the PDGF-BB. The bioinductive collagen suture introduces a platform for sustained delivery of other growth factors for a wide-array of applications.

Two-Blade Guillotine Technique for Nipple Graft Harvest.

The nipple-sharing technique for nipple reconstruction offers excellent tissue matching. The method used for nipple graft harvesting determines the quality of the graft and hence, the success of nipple sharing. Here, we described a guillotine technique wherein the nipple is first transfixed with 2 straight needles to stabilise it. Two No. 11 blades are then inserted in the center and simultaneously swept outwards to amputate the distal portion of the nipple. This technique provides good control, resulting in a very evenly cut base. The recipient bed is deepithelialized thinly, and the nipple graft is inset with interrupted 8-0 nylon sutures under magnification. Being a composite graft, it is protected with splint dressings for 6 weeks, and the dressing is regularly changed by the surgeon. The height of the nipple grafts ranges from 4 to 8 mm. This technique was performed in 9 patients with an average follow-up of 2.9 years (range, 1–4.5 years). Apposition between the nipple graft and its bed is crucial for the success of this technique. When correctly applied, we observed rapid revascularization of the graft.

Blockade of angiopoietin-2/Tie2 signaling pathway specifically promotes inflammation-induced angiogenesis in mouse cornea.

To investigate angiopoietin-2 (Ang-2)/Tie2 signaling pathway involving in inflammatory angiogenesis. Three interrupted 11-0 nylon sutures were placed into the corneal stroma of BALB/c mice (6wk old) to induce inflammatory neovascularization. Expression of Ang-2 and Tie2 protein on neovascularization were examined by immunofluorescence. The dynamic expression of Ang-2 mRNA on neovascularization was examined by quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Finally, the mouse model of suture-induced corneal neovascularization was used to assess the role of Ang-2/Tie2 signaling pathway in inflammatory angiogenesis by systemic application of L1-10, an Ang-2 specific inhibitor. Mouse corneal hemangiogenesis were evaluated by whole mount immunofluorescence. Both Ang-2 and Tie2 were expressed on newly generated blood vessels in inflammatory cornea. Ang-2 expression was gradually upregulated around 2wk following injury, which was concurrent with an increased number of blood vessels. Blockade of Ang-2/Tie2 signaling pathway obviously promoted angiogenesis in inflammatory cornea. Ang-2/Tie2 signaling pathway seems to play an important role during angiogenesis in inflammatory cornea. This may open new therapeutic applications in pathological processes such as corneal graft survival, wound healing and carcinogenesis.

Multiplanar Correction of the Lesser Digital Deviation and Indirect Plantar Plate Rupture Repair Using a Braided Polyethylene Nylon Suture: A Technique Guide.

Level V: Expert opinion.

Randomized controlled trial comparing outcome of use of staples and nylon sutures for closure in elective orthopedic surgery

Background: Wound complications are one of the major sources of morbidity after orthopaedic procedures and can prolong the inpatient stay or lead to re-admission. The most commonly used methods for skin closure after orthopaedic surgery are metal staples or nylon sutures Both methods act to hold the skin edges together while healing occurs. Metal staples are said to be superior as they are regarded as quicker as and easier than sutures.Objective: To compare outcome of use of staples and nylon sutures for wound closure in elective orthopedic surgery in term of infection rate,cosmetic appearance(Scar), time taken for skin closure.Methods: It is randomised controlled trial done on patients undergoing elective orthopaedic surgery at department of Orthopaedics at BPKIHS were included in the study. During procedure patients were evaluated for time taken for suture application or any complications.Results: A total of 60 patients (38 male and 22 female) were included in the study. Twenty two patients were between 41-55 years age group followed by fifteen patients between 25-40 yrs, twelve patients less than 25 age group and eleven patients more than 55 years. The average blood loss is 5 ml in K-wire group and 145 ml in plate group. The procedure time is 33 mins as comprared to 53 mins in plate group.Conclusion: Metal staples are superior as they are regarded as quicker and easier than nylon sutures. But use of metal staples or clips has a greater risk of wound infection and less acceptable cosmetically than sutures. Metal staples are more expensive. Health Renaissance 2015;13 (3): 137-143

English

Silibinin (Silybin) as an active constituent derived from milk thistle (Silybum marianum) has been shown to have antioxidant and anti-apoptotic properties. In traditional system of medicine, Silybum marianum has been used for treating various kinds of ailments including liver disease and cancer; however, clinical studies are largely heterogeneous and contradictory. The present study was designed to investigate whether Silibinin protects neuronal injury against middle cerebral artery occlusion induced oxidative stress associated damages in focal cerebral ischemia in Wistar rats. Rats weighing 250 to 300 g were pretreated with Silibinin 100 mg/kg and 200 mg/kg body weight, suspended in 0.5% of gum acacia) once daily for seven days. On 8th day, they underwent for middle cerebral artery 2 h suture occlusion by nylon suture. After 120 min of middle cerebral artery occlusion (MCAO) and 22 h of reperfusion, behavioral tests were assessed in terms of neurological deficits. Animals were sacrificed and infarct volume in Triphenyltetrazolium chloride (TTC) stained brain sections was measured. Further, various oxidative biomarkers were estimated in brain homogenates of rats. Pretreatment with Silibinin at doses of 100 and 200 mg/kg significantly improved the neurobehavioural alterations and reduced the infarct volume whereas 200 mg/kg Silibinin significantly increases the Glutathione (GSH) level and the others parameters with respect to control values. These results clearly indicate the neuroprotective effect of Silibinin against middle cerebral artery occlusion associated with oxidative damage induced brain injury due to its antioxidant and anti-apoptotic property. Key words: Neuroprotective, MCAO, Silibinin, oxidative stress, infarct volume, cerebral ischemia.

A Modified Technique of Temporary Suspension of the Ovary to the Anterior Abdominal Wall

Study ObjectiveTo demonstrate a modified technique of temporary suspension of the ovary to the fascia of the anterior abdominal wall after operative laparoscopy for advanced stage-endometriosis to reduce postoperative adhesion formation. DesignVideo illustrating this modified technique of ovarian suspension (Canadian Task Force classification III). SettingA previous study described a technique of temporary suspension of the ovary to the abdominal wall using nylon suture [1]. Here we demonstrate a modification of this technique involving underwent temporary suspension of the right ovary, using dissolvable 3-0 plain catgut suture, after operative laparoscopy for advanced-stage endometriosis (American Society for Reproductive Medicine stage III classification). InterventionsThis patient underwent right ovariolysis for stage III endometriosis. A CO2 laser was used to evaporate spots of endometriosis on the surface of the ovary, ovarian fossa, and the wall of a small endometrioma. A 3-0 plain catgut suture was placed in the right ovarian ligament, and the needle was cut and removed from the peritoneal cavity. The ends of the sutures were brought out of the peritoneal cavity through a 3-mm skin incision using an Endo Close device (Medtronic, Minneapolis, Minnesota). The suture was tied over the fascia while allowing CO2 gas out of the peritoneal cavity, to ensure that the suture remained under tension and the ovary was well suspended without touching the abdominal wall. The suture was used to elevate the ovary away from the ovarian fossa, to avoid recurrence of adhesions between it and the ovary. Postoperatively the patient did well and was discharged home on oral pain medication on the same day of surgery. No postoperative complications related to the suspension procedure were reported. The patient had an uneventful recovery. ConclusionThis modified approach of temporary ovarian suspension to the fascia of the anterior abdominal wall appears to be simple, safe, and easy to learn.

Establishing a Short Bowel Model in Mice as a Tool for Studying Genetic Risk Factors of Intestinal Failure

Introduction: Short bowel syndrome (SBS) is a severe condition in which the patient is unable to acquire enough energy due to insufficient bowel length. Failed surgery is the main reason for SBS. Therapy consists in total parenteral nutrition or bowel transplantation. Since the patient population with SBS is heterogenous and it is therefore difficult to perform studies, we established an experimental model to study adaptation in surgery induced short bowel in mice. Herein we report the results after the first 104 animals. Methods: Male C57B6/J mice (Jackson Laboratories) weighing approximately 30 g were switched to liquid diet ad libitum 48h before surgery. They were anaesthetized using ketamine/xylazine intraperitoneally. Mice were intubated and ventilated throughout surgery. Using the operation microscope, a median laparotomy was performed, the cecum exteriorized and 11 cm of small bowel proximal to the cecum exposed. The mesentery of this small bowel including the very proximal part of the ascending colon was clipped using micro clips, the bowel then resected. The bowel was anastomosed using 10–0 nylon suture performing 11–13 full thickness stitches. The bowel was then replaced into the abdominal cavity, irrigated with saline and the abdomen closed. The animals were kept on liquid diet for at least 1 week. Animal condition was measured daily using the wellness score. Sham operation with transection 11 cm proximal to the cecum was used as control. The study was approved by the local animal welfare committee. Results: Animals that died on the day of surgery or day one postoperatively were excluded from analysis because anesthesiologic reasons were observed. The mean length of resected bowel was 11.3 cm. Median body weight loss was 16% in the resected group compared to 8% in the sham group. Unlike Sham controls, resected mice developed diarrhea and prolonged weight loss. Overall survival was 69% in the resected group and 95% in the sham group. Causes of death or surgical complications of all 104 resected mice were ileus (12%), anastomotic insufficiency (6%), anastomotic stenosis (3%), others such as GI bleeding, lung edema etc.) and unknown (21%). The surgical procedure was adapted in course of training including using thinner suture material and different feeding postoperatively. Conclusion: We established a clinical relevant mouse model to study mechanisms of intestinal adaptation and the influence of genetic risk factors (NOD2 mutation or others) on the course of SBS.

Development of an objective method for the assessment of nylon sutures knot security

A perfect wound healing requires sutures having many handling characteristics such as good knot security and flexibility. Knot security characteristics are influenced by a variety of physical and mechanical parameters including the friction coefficient, bending rigidity and compressibility of the suture. Knot security and other handling characteristics are evaluated only by surgeons during the implantation. There are no standard tests to evaluate these qualities. We present in this paper an objective method to assess knot security of nylon sutures. This method is based on a fuzzy-logic model which correlates suture physical parameters and the knot security.

Microkeratome-Assisted Anterior Lamellar Keratoplasty for the Correction of High-Degree Postkeratoplasty Astigmatism.

To describe the surgical technique and report the outcomes of patients treated with microkeratome-assisted anterior lamellar keratoplasty (MALK) for the correction of high-degree postkeratoplasty astigmatism. Four eyes of 2 patients with extremely high (>10 D) and irregular [surface asymmetry index >1.0 D] post-penetrating keratoplasty astigmatism occurring after complete suture removal underwent MALK and were followed for at least 3 years after the procedure. In all cases, 250-µm lamellar keratectomy was performed, followed by 2 full-thickness incisions through the penetrating keratoplasty scar and the placement of an appropriately sized donor graft, which was secured with a double-running 10-0 nylon suture. All sutures were removed in all eyes within 1 year from surgery. Corrected distance visual acuity, refraction, corneal topography, and endothelial cell density were noted at each examination. At the last follow-up examination (3 years or longer after MALK), corrected distance visual acuity had improved to 20/20, refractive astigmatism had decreased to an average of 2.1 D (in all cases within 4.5 D), and the average surface asymmetry index had reduced from 2.27 to 0.56. MALK is an effective and safe technique for the correction of high-degree postkeratoplasty astigmatism.

Mechanical properties of 6 finger-trap suture techniques.

To identify the most common methods used by surgeons to place finger-trap sutures (FTS), and determine their influence on the biomechanical properties of constructs. Questionnaire and experimental study. Six commonly used FTS methods (A-F) were identified from literature review and questionnaire. Constructs made with 3-metric nylon suture and 18-French polyurethane esophagostomy tubing were tested in axial loading to failure. Two patterns (B and D) selected based on common use and biomechanical performance were further tested, with 2, 4, and 8 repeats along the tube. Displacement, load, and energy at failure were compared between constructs, and failure mode was video recorded. Patterns E and F were susceptible to slipping (P < .001). Patterns A and D were stiffer than pattern E, and patterns A-D were stiffer than pattern F (P = .012). Patterns A and B had less extension than pattern E and F, and patterns A-D had less extension than pattern F (P = .002). 87.5% of FTS failed by breaking at the first suture knot. The number of repeats had no effect on FTS performance, but catastrophic failure occurred in 2 constructs with 2 repeats. The mechanical behavior of suture-tube constructs and failure mode is affected by the FTS pattern. Patterns E and F are not advocated due to suture slippage. The number of repeats may not affect the FTS performance, but a minimum of 4 repeats is recommended. Overall, patterns B, C, and D performed the best in axial loading.

Abstract 3: Identification of Fibroblast Subtypes during Hypertrophic Scar Development

PURPOSE: The complex biological mechanisms occurring in hypertrophic scarring are still barely understood. However, the identification of (myo)-fibroblasts provides us with clues in determining the pathophysiology of fibrotic changes. Here, we focus on analyzing dermal fibroblast subtypes in murine dorsal skin following hypertrophic scarring in an in vivo model. We aim to understand the role of fibroblast subpopulations in the skin during healing and to determine their involvement in fibrotic scar development. METHODS: Hypertrophic scars (HTS) were induced by placing a biomechanical loading device onto the dorsum of C57/BL6 mice. On day 4 after causing an incisional wound, which was reapproximated immediately with 6-0 nylon sutures, the mechanical device was placed and tension was applied twice per day for 11 days. On day 11 all devices were removed. The scars of 10 HTS-mice were examined on day 11 and day 18 post-incision. Unwounded skin of C57/BL6-mice served as controls. Hypertrophic scars were identified via staining. The skin/tissue was digested and single cells were subjected to fluorescence-activated cell scanning (FACS) analysis and sorting to isolate cells of interest. Cells were negatively sorted for CD45, CD31 and EpCAM (CD326) and positively sorted for CD34, CD26 and CD55 to isolate fibroblasts and functional fibroblast subpopulations. RESULTS: FACS analysis revealed a change in the subpopulations of fibroblasts following mechanical stretching of the skin. Specifically, we observed decrease of the stemness marker CD34 in hypertrophic scars compared to unwounded skin. These changes were observed on day 11 as well as day 18 post-incision. CD34 is frequently used as a stemness marker and a marker of adipose-derived stem cells (ASCs). Hypertrophic scars were verified via staining (100% sensitivity). CONCLUSIONS: For the first time, our results reveal a decrease of the stemness marker CD34 in murine skin cells in hypertrophic scars over time compared to unwounded skin. We are currently conducting single cell transcriptional analyses and functional studies on these fibroblasts to understand the heterogeneity of fibroblasts during hypertrophic scarring and the specific role of CD34+ fibroblasts in skin fibrosis. Our findings have promising therapeutic implications for the treatment of skin fibrosis.

A Novel Method for Laser Suture Lysis Using Multispot Laser System.

Although often uncomplicated, the current technique for laser suture lysis after filtration surgery requires patient cooperation and appropriate care taken by the surgeon. In cases with suboptimal cooperation, steadying the 50-µm laser aiming beam exactly over a thin 10-0 nylon suture, can be exhausting, difficult for both the patient and the surgeon; it may prove to be ineffective or even precipitate complications. We describe a novel method for laser suture lysis using a multispot laser system, which requires less patient cooperation and surgeon skills and yields excellent results.

Large (9 mm) Deep Anterior Lamellar Keratoplasty with Clearance of a 6-mm Optical Zone Optimizes Outcomes of Keratoconus Surgery

To evaluate the outcomes of a 9-mm deep anterior lamellar keratoplasty (DALK) with removal of the deep stroma limited to the central 6-mm optical zone. Prospective, noncomparative, interventional case series. A total of 80 consecutive keratoconic eyes without deep stromal scarring, with at least 1 postoperative examination 1 month after complete suture removal. A standardized DALK was performed, including (1) deep trephination of the recipient bed 450 to 550 μm in depth and 9 mm in diameter; (2) pneumatic dissection; (3) debulking of approximately 80% of the anterior stroma; (4) removal of the deep stroma (bubble roof) from a central 6-mm optical zone; and (5) transplantation of a 9-mm anterior corneal lamella cut by microkeratome-assisted dissection (400-μm head) and sutured with a double running 10-0 nylon suture. Success rate and type of pneumatic dissection obtained; best spectacle-corrected visual acuity (BSCVA), refractive astigmatism (RA), and topographic astigmatism (TA), central corneal thickness (CCT) and endothelial cell density 12 months postoperatively; and intraoperative and postoperative complications. Pneumatic dissection created a "big bubble" in 67 of 80 eyes (83.7%), all of them but 1 (1.5%) being of type 1 according to the classification by Dua etal. After complete suture removal, BSCVA averaged 0.09±0.72 logarithm of the minimum angle of resolution (logMAR) and was ≥20/20 in 28 eyes (35%), ≥20/25 in 54 eyes (67.5%), and ≥20/40 in 76 eyes (95%); RA averaged 3.10±1.30 diopters (D), with 73 eyes (91%) within 4.5 D and none above 6 D; regular TA was detected in 72 eyes (90%); mean CCT was 492±62.10 μm; postoperative endothelial cell density averaged 2026±397cells/mm2 with a mean cell loss of 11.2%. Intraoperative complications included loss of suction (n= 1) and perforation (n= 4). No conversion to penetrating keratoplasty was necessary. After surgery, double anterior chamber was observed in 2 cases (2.5%), both managed successfully by air filling of the anterior chamber. Stromal rejection was observed in 6 eyes (7.5%) and was reversed with topical steroids in all cases. In keratoconic eyes without deep stromal scars, the combination of a graft larger than conventional ones with limited removal of deep stroma can improve visual and refractive outcomes of DALK, while minimizing the rate of complications.

Netrin-4 Mediates Corneal Hemangiogenesis but Not Lymphangiogenesis in the Mouse-Model of Suture-Induced Neovascularization.

Netrin-4, a secreted protein, is found in the basement membrane of blood vessels and acts as a key regulator of angiogenesis. Here we investigated the role of Netrin-4 in the mouse-model of suture-induced corneal hem- and lymphangiogenesis. Corneal hem- and lymphangiogenesis were induced in Netrin-4-deficient (Ntn4-/-) and wild-type (WT) mice by placing three 11-0 nylon sutures intrastromally. Fourteen days after suturing, the vascularized area was analyzed via corneal flat mount immunohistochemistry. Messenger RNA levels for VEGF-A, VEGF-C, Lyve-1, Netrin-4, Unc5H2, "deleted in colon cancer" receptor, and Neogenin in treated and nontreated mouse corneas, cultured human corneal keratocytes (HCK) and epithelial cells (HCEC+HCET) were analyzed by quantitative PCR. In wild-type mice, Netrin-4 mRNA expression in the cornea decreased in growing corneal neovascularization after suturing. Correspondingly, Ntn4-/- mice showed an increased vascularized area compared to that in WT mice. Expression of VEGF-A mRNA was higher in Ntn4-/- versus WT mice. There was no Netrin-4 expression in lymphatic vessels and the area of lymphatic vascularization did not differ between Ntn4-/- and WT mice, nor did expression of VEGF-C and Lyve-1 mRNA. Human corneal epithelial cells showed mainly Netrin-4 mRNA expression, which increased after stimulation, while HCK demonstrated Unc5H2 mRNA expression. Expression of VEGF-A, Netrin-4, Unc5H2, and Neogenin mRNA in HCEC and HCK did not differ significantly between the serum-free condition and VEGF-A or Netrin-4 stimulation. Absence of Netrin-4 increased corneal hemangiogenesis but not lymphangiogenesis in the mouse-model of suture-induced neovascularization. Netrin-4 acted as an antiangiogenic factor in the cornea, with which the healthy cornea is enriched via its expression by corneal epithelial cells.

Suture-guided sulcus implantation of a single-piece foldable acrylic intraocular lens after posterior capsule rupture

We describe a technique for suture-guided sulcus implantation of a foldable acrylic posterior chamber IOL (PC IOL). A 10-0 monofilament nylon suture is used to control insertion of the PC IOL over the ciliary sulcus and enable safe retrieval if the PC IOL drops during insertion, stabilization, or centration. In this technique, the 10-0 monofilament nylon suture acts as a guy rope to hold onto the PC IOL, enabling the surgeon to inject the IOL into the sulcus, unfold it in the iris plane, dial it in the appropriate meridian, and stabilize it.

Patch Angioplasty in the Rat Aorta or Inferior Vena Cava.

Pericardial patches are commonly used in vascular surgery to close vessels. To facilitate studies of the neointimal hyperplasia that forms on the patch, we developed a rat model of patch angioplasty that can be used in either a vein or an artery, creating a patch venoplasty or a patch arterioplasty, respectively. Technical aspects of this model are discussed. The infra-renal IVC or aorta are dissected and then clamped proximally and distally. A 3 mm venotomy or arteriotomy is performed in the infrarenal inferior vena cava or aorta of 6 to 8 week-old Wistar rats. A bovine pericardial patch (3 mm x 1.5 mm x 0.6 mm) is then used to close the site using a 10-0 nylon suture. Compared to arterial patches, venous patches show increased neointimal thickness on postoperative day 7. This novel model of pericardial patch angioplasty can be used to examine neointimal hyperplasia on vascular biomaterials, as well as to compare the differences between the arterial and venous environments.