Application of collagen matrix (DuraGen®) to reduce subcutaneous emphysema in canine dorsal rhinotomy.

This retrospective case study aimed to evaluate the efficacy of collagen matrix (DuraGen®) in preventing subcutaneous emphysema, a common complication following dorsal rhinotomy. Six client-owned dogs diagnosed with nasal masses using computed tomography were included in this study. Dorsal rhinotomy was performed, and a collagen matrix was used to seal bone defects before fixation of the nasal bone flap. Following collagen matrix application, all dogs recovered without notable complications. These findings suggest that the collagen matrix is a reliable and safe intervention for mitigating subcutaneous emphysema after dorsal rhinotomy.

Duragen: A dermal substitute for the management of suboptimal wounds.

Using a flap in a large wound with a very small area of exposed vital structures may be an excessive intrusion and cause unnecessary donor site morbidity. Dermal matrix (DuraGen) was applied onto critical areas where bone or tendons were exposed and a split skin graft was placed thereon. All patients had satisfactory wound closure without the need for a flap. DuraGen appears to be a safe, single-stage alternative, to a flap for the healing of complex wounds.

Comparative evaluation of Duragen® and skim milk extenders to enhance ram semen quality and fertility: A promising alternative in ovine artificial insemination.

This study aimed to investigate the effectiveness of Duragen® and skimmed milk (SM) extenders on the quality parameters, bacterial load and fertilization ability of stored ram semen. A total of 50 ejaculates from Sardi rams (n = 5) aged 2.5-3 years, were collected and stored in Duragen® and SM at 15°C. The motilities and velocity parameters generated by the CASA system were then evaluated at 0, 8 and 24 h of storage. Afterward, bacterial loads of sperm extended in Duragen® and SM were determined at 0, 5 and 24 h of incubation. In addition, ewes (n = 100) aged 2 years, have been chosen in the same herd. The selected ewes were then synchronized and inseminated using semen extended in Duragen® and SM and stored for 5 h at 15°C. The results revealed that total and progressive motilities, straight velocity (VSL), straightness (SRT), lateral head displacement (ALH) and beat cross frequency (BCF) were not affected by the extender type after 24 h of storage (p > .05). However, curvilinear velocity (VCL), velocity average path (VAP), linearity (LIN) and wobble (WOB) showed higher values in Duragen® compared with SM extender after 24 h of storage (p < .05). Bacterial loads were observed mainly in sperm stored in SM at 5 h (183 UFC/mL) and at 24 h (357 UFC/mL) of incubation. However, the only case showing a bacterial load in Duragen® is when the storage time attains 24 h (199 UFC/mL). Concerning fertility, sperm diluted in both extenders resulting in high fertility rates which reaches 66% and 73% for Duragen® and SM, respectively, with no statistical difference (p > .05). In summary, Duragen® extender decreased bacterial load in stored semen and maintained high ram sperm quality and fertility. These findings suggest that Duragen® extender could be used as SM alternative in ovine artificial insemination (OAI).

Meningioma Cell Invasion into DuraGen-Derived Dura Mater: A Case Report.

Background: Dura mater infiltration is the main growth pattern of meningiomas. Local recurrence may occur in any type of meningioma, but it is more likely so in atypical meningiomas. Therefore, a wide resection of tumor cell-invaded dura mater is necessary to avoid recurrence. DuraGen® (an artificial dural substitute) can be used for dural reconstruction in meningiomas. Here, we report a rare case of a patient with atypical meningioma that invaded into the DuraGen®-derived mature dura mater. Case presentation: A 66-year-old female showed a three-time recurrence of atypical meningioma. Simpson grade I resection (en bloc tumor with autologous dura mater and DuraGen®-derived dura mater resection) was achieved at the 3rd recurrence. Collagen fibers running regularly and transversely were observed in the DuraGen®-derived dura mater resembling the autologous meningeal layer. Meningioma cell invasion, displayed by occasional EMA immunostaining, was observed in the DuraGen®-derived dura mater. Conclusions: This case indicates that meningioma cells may invade and survive in the DuraGen®-derived dura mater. Whether or not DuraGen® is not appropriate as a dural substitute remains unanswered. Further experiences are needed to validate these findings in large sample sizes.

Modified Shoelace Dural Closure with Collagen Matrix in Extended Transsphenoidal Surgery.

Extended endonasal transsphenoidal surgery (eTSS) offers a wide surgical field for various parasellar lesions; however, intraoperative high-flow cerebrospinal fluid (CSF) leakage is inevitable. Therefore, secure sellar reconstruction methods are essential to prevent postoperative CSF leakage. Although collagen matrix has been applied for dural reconstruction in neurosurgery, its suitability for application in extended eTSS remains unclear. Eighteen patients underwent modified shoelace dural closure using collagen matrix after lesionectomy via extended eTSS. In this technique, a collagen matrix, which was placed subdurally (inlay graft), was continuously sutured with both open dural edges like a shoelace. Then, another collagen matrix was placed epidurally (onlay graft), and rigid reconstruction was performed using the septal bone and a resorbable fixation mesh. Postoperative CSF leakage did not occur in 17 patients but did occur in 1 patient with tuberculum sellae meningioma. In this case, the CSF leakage point was detected just around the area between the coagulated dura and the adjacent collagen matrix. The collagen matrix harvested from this area was pathologically examined; neovascularization and fibroblastic infiltration into the collagen matrix were not detected. On the other hand, neovascularization and fibroblast infiltration into the collagen matrix were apparent on the surface of the collagen matrix harvested from the non-CSF leakage area. Our novel dural closure technique using collagen matrix could be an effective option for sellar reconstruction in extended eTSS; however, it should be applied in patients in whom normal dural edges are preserved.

Double collagen matrix grafting for dural closure in microvascular decompression: an alternative use of autologous fascial grafting.

BACKGROUND: Watertight dural closure is a crucial step in preventing postoperative cerebrospinal fluid (CSF) leak and subsequent infection in posterior fossa surgery. The aim of this study is to assess an alternative use of collagen matrix double grafting in microvascular decompression (MVD). METHODS: Dural closure using double collagen matrix grafts was retrospectively compared with autologous fascial grafting in 120 patients who underwent MVD. Double collagen matrix grafting technique, a combination use of inlay and onlay grafting (DuraGen®, Integra Lifesciences, Plainsboro, NJ, USA, $700-800 for an MVD craniotomy size), was applied in 60 patients (the collagen matrix group). In the remaining 60 patients, an autologous fascial graft was sutured in a watertight fashion to the dural defect (the fascia group). Postoperative wound complications, such as CSF leak and infection, were retrospectively compared between the two groups. RESULTS: CSF leaks were observed in 3 patients (5.0%) in the fascia group and in 2 patients (3.3%) in the collagen matrix group. All cases of CSF leakage presented with pseudomeningoceles except one patient who developed an incisional CSF leak. A repair surgery for CSF leak was required in this one patient in the fascia group. Subcutaneous abscesses were noted in 2 patients (3.3%) in the fascia group. There was no patient who developed a subcutaneous abscess in the collagen matrix group. One patient in each group developed aseptic meningitis. Statistical analyses revealed that the collagen matrix group showed non-inferior outcomes to the fascia group in CSF leaks and infectious complications. CONCLUSIONS: Double grafting technique with a combination of inlay and onlay collagen sheets is a safe and secure alternative for watertight dural closure despite a cost limitation.

Endoscopic-assisted Duraplasty with Collagen Matrix for Growing Skull Fracture: A Case Report.

Growing skull fracture (GSF) is a rare complication of pediatric head injury. Early diagnosis and immediate surgical intervention are required for the prevention of irreversible brain damage. Surgical management involves water-tight closure of the dural defect and commonly uses autologous materials because of tissue compatibility; however, a large skin flap and craniotomy are necessary to harvest the autologous materials and repair the dural defect. We describe a successful case of endoscopic-assisted duraplasty using collagen matrix in a female infant suffering from early phase GSF. A 4-month-old female infant presented with a GSF. We surgically treated her because the fracture width progressively expanded 6 days post-injury. A zigzag skin incision was made, and the extent of the skull fracture and dural laceration was observed using an endoscope. Utilizing the collagen matrix, duraplasty was performed to completely seal the dural defect. Subsequently, cranioplasty was performed and the opposite sides of the fracture margins were drawn and bonded by nylon suture. Postoperatively, the patient did not develop any complication or experience recurrence. This is the first report of duraplasty using collagen matrix in GSF, and the collagen matrix can be used as a dural substitute. This novel technique was safe and a less invasive surgical approach for treating patients with GSF.

Outcomes of Surgical Repair of Skull Base Defects Following Endonasal Pituitary Surgery: A Retrospective Observational Study.

Skull base defects following endonasal surgery for pituitary macroadenoma need to be addressed during the surgery to prevent serious postoperative complications like cerebrospinal fluid (CSF) leak. The objective of this study is to assess the incidence of CSF leak following pituitary surgery and the methods of effective skull base repair. This is a retrospective observational study conducted in a tertiary care hospital after obtaining due clearance from the Institutional ethics committee. The charts of patients who underwent endonasal pituitary surgery between 2013 and 2018 were studied and details noted. Patients undergoing revision surgery or with history of preoperative radiotherapy were excluded from the study. 52 patients were included in the study. Based on the type of CSF leak, the patients were grouped into four. 19 patients (36.5%) had an intraoperative CSF leak. 3 patients developed a postoperative CSF leak. Based on the histopathology, 4 patients had ACTH secreting tumor. 8 patients had growth hormone secreting tumor, 22 had gonadotropin secreting tumor, 9 patients had a non-functioning tumour and 9 patients had prolactinoma. The type of skull base repair performed in these patients were grouped into 4.18 patients underwent type I repair, 21 patients underwent type II repair, 8 patients underwent type III repair and 5 patients underwent type IV repair. We have observed that the pedicled nasoseptal flap is particularly advantageous over other repair techniques, especially in low pressure leaks. The strategy for skull base repair should be tailored to suit each patient to minimise the occurrence of morbidity and the duration of hospital stay.

Transcutaneous Drainage of Gel-Like Substance after Application of Hydrogel Dural Sealant: Report of Two Cases.

Study Design Case report. Objective Incidental durotomy (IDT) is a common complication of spinal surgery. The use of collagen matrix graft along with hydrogel dural sealant is a common method of IDT repair. With this method, there have been several reported cases of detrimental dural sealant expansion in the literature. One case study reported an expansion rate greater than 300%; many report neurologic damage. This article reports the clinical course of two patients who developed postoperative transcutaneous drainage of a gel-like substance after the use of a dural sealant, which is a previously unreported complication. Methods The clinical course and treatment outcome of two patients is presented. Results Both patients experienced postoperative transcutaneous drainage of a gel-like substance at the surgical site. Case one began draining this substance on postoperative day 14. This patient required no further intervention, and the drainage ended after 3 mL of a gel-like substance was expressed from his incision while in the clinic. Case two began draining the gel on postoperative day 16. This patient underwent two washout procedures and resolution of the drainage. No infection was ever detected. Conclusions To our knowledge, our patients are the first reported cases of transcutaneous drainage of expanded dural sealant. It is important to take into consideration the unexpected expansion of a dural sealant when using it for the repair of IDT.

Suramin, Genistein and Collagen Matrix (DuraGen) for Delayed Adjustment after Strabismus Surgery: Which One is Best?

AIM: To evaluate the efficacy and safety of suramin, genistein and collagen matrix for the prevention of inflammation, the reduction of fibrosis and the delay in adjustment after strabismus surgery on a rabbit model. METHODS: By using an adjustable suture technique, a recession of the superior rectus muscle (SRM) was made in 36 eyes of 18 rabbits. Three study groups were created using genistein, suramin and collagen matrix (n = 6 per group). Two control groups utilized dimethyl sulphoxide (DMSO) (n = 6) and balanced salt solution (n = 12). The adjustments and measurements were made on days 2, 7, 14. After enucleation was done on day 21, the degree of inflammation was evaluated quantitatively in histopathological sections and immunohistochemical investigations were performed for tissue expression of cytoplasmic vascular endothelial growth factor (VEGF), MAC 387, TGF-ß and bFGF. RESULTS: The adhesions between conjunctiva and SRM were significantly less in the collagen matrix and suramin groups (p = 0.002) and adhesions between the sclera and SRM were considerably reduced in the genistein and DMSO groups (p = 0.006) on day 7. Force exerted for adjustment was significantly less in the collagen matrix and suramin groups on day 14 (p = 0.006). Expression of b-FGF was significantly lower in the conjunctival epithelium in the suramin and genistein groups (p = 0.0001 for both). TGF-ß was significantly lower (p = 0.001) in the suramin group and VEGF expression was totally absent. MAC 387 expression was lower in the genistein and suramin groups (p = 0.0001). CONCLUSION: Suramin, genistein and collagen matrix successfully reduce adhesions, and facilitate adjustment following recession surgery. Both suramin and genistein effectively suppress growth factor expression, while collagen matrix offers the longest time interval for adjustability after strabismus surgery.