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BackgroundBurn infliction techniques are poorly described in rat models. An accurate study can only be achieved with wounds that are uniform in size and depth. We describe a simple reproducible method for creating consistent burn wounds in rats.MethodsTen male Sprague-Dawley rats were anesthetized and dorsum shaved. A 100 g cylindrical stainless-steel rod (1 cm diameter) was heated to 100℃ in boiling water. Temperature was monitored using a thermocouple. We performed two consecutive toe-pinch tests on different limbs to assess the depth of sedation. Burn infliction was limited to the loin. The skin was pulled upwards, away from the underlying viscera, creating a flat surface. The rod rested on its own weight for 5, 10, and 20 seconds at three different sites on each rat. Wounds were evaluated for size, morphology and depth.ResultsAverage wound size was 0.9957 cm2 (standard deviation [SD] 0.1845) (n=30). Wounds created with duration of 5 seconds were pale, with an indistinct margin of erythema. Wounds of 10 and 20 seconds were well-defined, uniformly brown with a rim of erythema. Average depths of tissue damage were 1.30 mm (SD 0.424), 2.35 mm (SD 0.071), and 2.60 mm (SD 0.283) for duration of 5, 10, 20 seconds respectively. Burn duration of 5 seconds resulted in full-thickness damage. Burn duration of 10 seconds and 20 seconds resulted in full-thickness damage, involving subjacent skeletal muscle.ConclusionsThis is a simple reproducible method for creating burn wounds consistent in size and depth in a rat burn model.

Orbital reconstruction is a difficult procedure, success of which is dependent on the surgeon's experience. The lack of objective methods requires a fair amount of estimation is its execution. This study evaluates the efficacy of Kolibri (BrainLab, Munich, Germany), an intraoperative navigation device, in improving outcomes. From 2004 to 2009, 58 patients with orbital trauma who underwent surgery at the National University Hospital, Singapore, were included in this prospective matched control trial. Twenty-nine consecutive patients underwent surgery with Kolibri. The control group underwent surgery without the device. Both groups were matched for age, sex, orbital wall fracture, preoperative ophthalmologic features, etiology and severity of trauma, surgical approach, and types of implant used. The postoperative follow-up was at 1, 3, 6, and 12 months. For subjective assessment, the postoperative ophthalmologic features, including diplopia, infraorbital hypoesthesia, ophthalmoplegia, and enophthalmos, were compared. At 1, 3, 6, and 12 months, respectively, there were fewer patients with postoperative ophthalmologic complications in the study group (italicized; n = 29) compared with the control group (n = 29; P < 0.05): 12/29 (41%) versus 21/29 (72%), 8/29 (28%) versus 19/29 (66%), 5/29 (17%) versus 15/29 (52%), and 2/29 (7%) versus 12/29 (41%). For objective assessment, using the Kolibri workstation, operative plans were created and fused with postoperative computed tomographic scans. Vertical distances between the actual reconstructed and planned orbital floors were measured. On average, the vertical distance measured from the boundaries of floor defects for patients in the study group was 3.24 mm (95% confidence interval, 1.56-4.91) lower than the control group (P = 0.001). In conclusion, navigation minimizes postoperative complications, reduces the need for repeat procedures, and helps surgeons with planning, execution, and postoperative assessment.

BackgroundThe combination of polycaprolactone and hyaluronic acid creates an ideal environment for wound healing. Hyaluronic acid maintains a moist wound environment and accelerates the in-growth of granulation tissue. Polycaprolactone has excellent mechanical strength, limits inflammation and is biocompatible. This study evaluates the safety and efficacy of bio-conjugated polycaprolactone membranes (BPM) as a wound dressing.Methods16 New Zealand white rabbits were sedated and local anaesthesia was administered. Two 3.0×3.0 cm full-thickness wounds were created on the dorsum of each rabbit, between the lowest rib and the pelvic bone. The wounds were dressed with either BPM (n=12) or Mepitel (n=12) (control), a polyamide-silicon wound dressing. These were evaluated macroscopically on the 7th, 14th, 21st, and 28th postoperative days for granulation, re-epithelialization, infection, and wound size, and histologically for epidermal and dermal regeneration.ResultsBoth groups showed a comparable extent of granulation and re-epithelialization. No signs of infection were observed. There was no significant difference (P>0.05) in wound size between the two groups. BPM (n=6): 8.33 cm2, 4.90 cm2, 3.12 cm2, 1.84 cm2; Mepitel (n=6): 10.29 cm2, 5.53 cm2, 3.63 cm2, 2.02 cm2; at the 7th, 14th, 21st, and 28th postoperative days. The extents of epidermal and dermal regeneration were comparable between the two groups.ConclusionsBPM is comparable to Mepitel as a safe and efficacious wound dressing.

The first complication was flap epidermolysis on one side. This was the first case to undergo surgery, and was possibly caused by technical error in flap dissection. It was managed conservatively. The other complication was wound dehiscence caused by frequent asthmatic attack and respiratory tract infection. This case was managed conservatively with satisfactory healing.The paraphiltral flap has many advantages, such as reliable blood supply, ability to reconstruct the whole length and depth of the columella, closure of the donor site primarily, preservation of aesthetic units of the upper lip, asymmetry of both nares, and closure of the donor sites closed along the philtral line. Inclusion of the orbicularis oris muscle in the flap helps to augment the blood supply and to add bulkiness to the flap without the need for additional cartilage graft. Although cartilage graft was not used, the flap has the ability to host a cartilage graft. Last but not least, the donor area can be reused again.

PTI allows users to visualize veins invisible to the naked eye. Thrombosed/tortuous veins, branch points and valves, are easily identified and avoided. It has comparable efficacy to Veinlite and is cheaper (Veinlite-USD 227 vs. Penlite-LP212-USD 7.00) and more easily available. PTI improves patient care, especially in developing regions where costs are a concern.

Purpose: Planes of reference for orbital fractures (PROF) was developed to standardize measurements made on orbital computed tomography scans. This study describes the use of PROF in determining the location along the orbital floor where the posterior ledge (PL) most commonly occurs. The transverse inclination and anterior-posterior inclination of the orbital floor will also be measured. Methods: This study evaluates 104 patients with unilateral orbital fracture. Fifty-two patients had intact infra-orbital margin (IM) and 52 had fractured IM. Facial computed tomography scans were analyzed using Osirix Lite Digital Imaging and Communications in Medicine Viewer version 7.0.1 (Geneva, Switzerland). All skull positions were standardized by orientation according to Frankfurt and mid-sagittal planes. Measurements of distance of PL from IM were determined in the sagittal view. Measurements of the inclination of the orbital floor in the transverse and anterior-posterior sections were done on the coronal and sagittal views respectively. Results: For patients with intact and fractured IM, the mean distances of PL from IM were 22.1 mm (95% CI: 21.2–23.0) and 21.1 mm (95% CI: 20.2–21.9) respectively. Mean transverse inclination was 19.4° (95% CI: 18.3–20.5). Mean anterior-posterior inclination was 15.5° (95% CI: 14.5–16.5). Conclusion: Planes of reference for orbital fractures is a simple and effective method to acquire standardized measurements of the orbital cavity on computed tomography scans. Understanding the commonest location of PL and the orientation of the orbital floor in 3-dimensional space allows surgeons to perform dissection with greater precision.

Implant exposure is a known complication of titanium mesh cranioplasty and is usually managed by implant removal and/or exchange. We describe a case of exposed titanium mesh cranioplasty which was managed with implant exchange and bipedicled flap coverage, and showcase an interesting phenomenon of full-thickness skin present beneath the exposed mesh. This was confirmed on histopathology, which showed the presence of dermal appendages including pilosebaceous units and eccrine glands. We postulate that the mechanism behind this phenomenon involves islands of viable skin ‘dropping’ between holes in the mesh and coalescing beneath the exposed implant, as suggested by histopathology findings of nodular protrusions and varying degrees of epidermal hyperplasia. This protects the underlying dura from external infection. We propose for this phenomenon to be called dermointegration. Our findings suggest that similar cases, particularly patients who are not fit for general anaesthesia, may potentially be managed with a more conservative approach.