Scalp Metastases of Recurrent Meningiomas: Aggressive Behavior or Surgical Seeding?

OBJECTIVE: Scalp metastases of meningiomas seldom have been reported. Here, we report a series of 4 cases of this rare event and discuss the relevant potential risk factors. METHODS: We performed a retrospective review of patients treated for scalp metastases of meningiomas at our institution. A literature review was performed for the terms "scalp meningioma," "cutaneous meningioma," "skin meningioma," "extracranial meningioma," and "subcutaneous meningioma." RESULTS: Four patients showed scalp metastases of recurrent meningiomas with the following associated clinical features: multiple reoperations (n = 4), immunosuppression (n = 2), radiation therapy (n = 3), surgical wound complications with cerebrospinal fluid fistula (n = 2), and histologic grade progression (n = 2). The timescale for development of scalp metastasis was between 5 months and 13 years after intracranial meningioma surgery. In all cases, the metastases were located close to the surgical scalp incision for the craniotomy. Previously, 11 cases of meningioma with scalp metastasis, with similar features to those described here, were reported in the literature. CONCLUSIONS: Spreading of meningioma cells during surgery is a possible mechanism for scalp metastases of recurrent meningiomas. Factors associated with scalp metastases include reoperations, immunosuppression, radiation therapy, torpid course of the surgical wound with cerebrospinal fluid fistula, and histologic progression. Awareness of these features is advisable for neurosurgeons involved in the care of patients with similar profiles.

Anatomical variability of descending genicular artery.

BACKGROUND: The main objective of this article was to provide a detailed description of the variability of the vascular anatomy of the medial femoral condyle corticoperiosteal flap. METHODS: The authors performed an anatomical dissection of the medial aspect of the genicular area of 20 lower limbs. The dissection isolated the different branches of the descending genicular artery (muscular, articular, and saphenous), after which the different branching patterns were recorded. Also the length, diameter, and distances of the main artery and its branches to the medial joint line of the knee were measured. RESULTS: Three types of branching were identified, depending on whether all 3 branches shared a common origin (60%); only one of the branches had an isolated origin (30%); or all 3 branches had isolated origins (10%). The mean diameter of the descending genicular artery was 1.77 mm and arose from the femoral artery, 12.83 cm proximal to the medial joint line of the knee. The descending genicular artery was accompanied by 2 concomitant veins with a mean diameter of 1.98 mm. The articular branch reached the medial femoral condyle 6.2 cm proximal to the medial joint line of the knee. The average length of the articular branch from its origin was 5.3 cm. CONCLUSIONS: Despite the relative anatomical variability, in 85% of cases, it is possible to elevate a corticoperiosteal graft using the descending genicular artery in association with other anatomical structures. The dissection of the corticoperiosteal medial condyle flap only becomes complicated with short vascular pedicles if the origin of the articular branch is isolated in the femoral artery.

Do collagen meshes offer any benefits over preclude® ePTFE implants in contaminated surgical fields? A comparative in vitro and in vivo study.

The surgical repair of an abdominal wall defect may be complicated by infection. We examined the in vitro and in vivo behavior of Staphylococcus aureus (Sa) and Staphylococcus epidermidis (Se) when placed in contact with three collagen bioprostheses. For the in vitro study, 1 cm(2) fragments of the collagen meshes (Collamend®, Surgisis®, and Permacol®) and a control polytetrafluoroethylene mesh, Preclude®(ePTFE) were incubated on blood agar plates inoculated with Sa or Se. In the in vivo study, 2 partial 3 × 3 cm defects were created in the abdominal wall of 72 rabbits and infected with a suspension-containing 10(6) Colony-forming unit (CFU) of Sa or Se. The defects were then repaired using the above materials. At 14 and 30 days postimplant, mesh specimens were obtained for histological, morphometric, and biomechanical analysis. The incubated collagen meshes showed significantly greater bacterial loads than the ePTFE. In vivo, large abscesses comprised of bacteria (Sa/Se), detritus and white cells could be seen 14 days post-implant. At 30 days, the bacterial infiltrate was reduced in the Se group. In conclusion, in presence of bacterial contamination, no benefits were observed of the use of the collagen bioprostheses tested over the use of a non porous ePTFE mesh (Preclude®).

Vascular anatomy of the dorsum of the foot.

BACKGROUND: The authors' purpose was to study the anatomy of the dorsum of the foot and determine the distribution and caliber of all vascular branches that nourish the skin and the extensor hallucis longus and extensor digitorum longus tendons. METHODS: The authors performed 20 cadaver dissections. The skin paddle was designed within the dorsum of the foot. Dissection continued until all vascular branches that nourished the skin and tendons were identified. The authors measured the caliber of the vascular connections and the distance to the proximal end of the extensor retinaculum. RESULTS: The dorsalis pedis artery was the continuation of the anterior tibial artery in all cases. A mean of five cutaneous perforators irrigated the cutaneous paddle with a mean caliber of 0.53 mm. The paratenon of the extensor hallucis longus tendon was vascularized by a mean of 8.1 vascular branches with a mean diameter of 0.71 mm. The paratenon of the extensor digitorum longus tendon was nourished by a mean of 5.4 vascular branches, and the mean caliber of those branches was 0.65 mm. CONCLUSION: The dorsum of the foot presents a constant vascular anatomy that is well suited for the elevation of different types of compound flaps which, in turn, would adapt to the needs of the defect.