Acute effects of splint immobilization of the forearm on in vivo microcirculation and histomorphology of the human skin.

BACKGROUND: Splint immobilization of the forearm is often performed in clinical practice. Previous studies investigated the effect of immobilization on bone, cartilage, muscle, and tendon, however, the acute effects on human skin microcirculation and histomorphology remains elusive. METHODS: In 12 healthy, nonsmoking individuals (aged 29.7 ± 9.1 years) a randomly selected forearm was immobilized by splinting for 72 h, whereas the other forearm served as control. In vivo Reflectance-Mode Confocal-Microscopy (RMCM) was performed prior (baseline value) and postimmobilization to evaluate: quantitative blood cell flow; density of functional dermal capillaries; epidermal thickness; and granular cell size. RESULTS: At 72h forearm immobilization, quantitative blood cell flow was significantly reduced (42.86 ± 3.68 cells/min) compared to the control blood flow (53.11 ± 3.68 cells/min, P < 0.05) and dermal capillaries indicates less functional density (5.73 ± 0.63 capillaries/mm2) compared to the controls (7.04 ± 0.81 capillaries/mm2, P < 0.05). Histometric assessment reveals significantly thinner epidermis following immobilization compared to the control site (40.02 ± 2.91 vs. 46.64±3.09 µm, P < 0.05). Granular cell size was significantly altered at 72 h splinting (730.1 ± 42.53 µm2) compared to the control cell size at 770.2 ± 38.21 µm2. Comparison of baseline values of both forearms indicate statistically insignificance (P > 0.05) for each parameter. CONCLUSION: At 72 h splint immobilization, for the first time, significant adaptive mechanisms were evaluated on human skin microcirculation and histomorphology using in vivo RMCM. These adaptations may be considered as an incipient atrophy of the human skin. Long-term effects of immobilization including the regenerative potential should be evaluated in further RMCM studies.

Acute effects of local cold therapy in superficial burns on pain, in vivo microcirculation, edema formation and histomorphology.

BACKGROUND: Local cold therapy for burns is generally recommended to relief pain and limit tissue damage, however, there is limited data of its physiological benefit. This study aimed to evaluate pathophysiological effects of cold therapy in superficial burn on microcirculation, edema formation, and histomorphology. METHODS: In 12 volunteers (8f, 4m; aged 30.4±14.1 years) circumscribed superficial burn was induced on both hand back and either left untreated as control (control-group) or treated by local-cold-application (cold-treatment-group). Prior to burn (t0), immediately (t1), 15 min (t2), and 30 min (t3) following cold therapy, following parameter was evaluated using intravital-microscopy; epidermal-thickness (ET), granular-cell-size (GCS), individual-blood-cell-flow (IBCF), and functional-capillary-density (FCD). RESULTS: Both ET and GCS increased significantly more in control-group and slightly in cold-treatment-group in t1, while turns to insignificant t2 onwards. IBCF and FCD raised up in control-group compared to dramatically decrease in cold-treatment-group in t1. In t2 both parameter remains in control-group and increased in cold-treatment-group. Comparison of both groups for IBCF and FCD indicates significant difference in t1 and t2, however, insignificant in t0 and t3. CONCLUSIONS: Microcirculation, edema formation, and histomorphology of superficial burn has been significantly influenced through immediate cold therapy, however, this alterations are transient and turns to ineffective after 30 min.

Insight in human skin microcirculation using in vivo reflectance-mode confocal laser scanning microscopy.

Reflectance-mode confocal laser scanning microscopy allows in vivo imaging of the human skin. We hypothesized that this high-resolution technique enables observation of dynamic changes of the cutaneous microcirculation. Twenty-two volunteers were randomly divided in two groups. Group 1 was exposed to local heating and group 2 to local cold stress. Confocal microscopy was performed prior t (0) (control), directly t (1) and 5 min t (2) after local temperature changes to evaluate quantitative blood cell flow, capillary loop diameter, and density of dermal capillaries. In group 1, blood flow increased at t (1) (75.82 +/- 2.86/min) and further at t (2) (84.09 +/- 3.39/min) compared to the control (61.09 +/- 3.21/min). The control capillary size was 9.59 +/- 0.25 microm, increased to 11.16 +/- 0.21 microm (t (1)) and 11.57 +/- 0.24 microm (t (2)). The dermal capillary density increased in t (1) (7.26 +/- 0.76/mm(2)) and t (2) (8.16 +/- 0.52/mm(2)), compared to the control (7.04 +/- 0.62/mm(2)). In group 2, blood flow decreased at t (1) (41.73 +/- 2.61/min) and increased at t (2) (83.27 +/- 3.29/min) compared to the control (60.73 +/- 2.90/min). The control capillary size was 9.55 +/- 0.25 microm, decreased at t (1) (7.78 +/- 0.26 microm) and increased at t (2) (11.38 +/- 0.26 microm). Capillary density decreased at t (1) (5.01 +/- 0.49/mm(2)) and increased at t (2) (7.28 +/- 0.53/mm(2)) compared to the control (7.01 +/- 0.52/mm(2)). Confocal microscopy is a sensitive and noninvasive imaging tool for characterizing and quantifying dynamic changes of cutaneous microcirculation on a histomorphological level.

Monitoring of microcirculation in free transferred musculocutaneous latissimus dorsi flaps by confocal laser scanning microscopy--a promising non-invasive methodical approach.

INTRODUCTION: For the survival of a microvascular tissue transfer, early detection of vascular complications is crucial. In vivo confocal laser scanning microscopy allows real-time, non-invasive evaluation of tissue microcirculation with a high cellular resolution. The aim of this study was to evaluate confocal laser scanning microscopy for early recognition of flap failure. METHODS: Fourteen patients (ages: 40.2+/-12.4 years) were monitored postoperatively for a period of 24h following free microvascular M. latissimus dorsi transfer to the lower extremity using confocal laser scanning microscopy (Vivascope1500; Rochester; New York; USA). The following parameters were evaluated: quantitative blood-cell flow, diameter of capillary loops and minimal thickness of the epidermis. RESULTS: Venous congestion was characterised by a decrease in blood-cell flow of up to 41%, accompanied by an increase of the diameter of capillary loops of up to 22% and the minimal thickness of the epidermis up to 32%. By contrast, arterial occlusion was clearly verified by a decrease in blood flow of up to 90%, accompanied by an insignificant change of both capillary loop size and epidermal thickness. CONCLUSION: Confocal laser scanning microscopy appears to be a useful non-invasive tool for early recognition of flap failure during the monitoring of microsurgical tissue transfer prior to its clinical manifestation.

Is superficial burn caused by ultraviolet radiation (sunburn) comparable to superficial burn caused by heat--a histomorphological comparison by in vivo Reflectance-Mode-Confocal Microscopy.

BACKGROUND: Regardless of the underlying cause, both sunburn and superficial thermal injuries are classified as first-degree burns, since data on morphological differences are scarce. Reflectance-Mode-Confocal Microscopy (RMCM) enables high-resolution non-invasive investigation of the human skin. OBJECTIVE: We studied in vivo histomorphological alterations in both sunburn and superficial thermal injuries using RMCM. METHODS: Ten patients (6 female, 4 male; aged 28.4 +/- 10.6 years) with first-degree thermal-contact Injuries (TI group), and 9 sunburned patients (SB group; 7 female, 2 male; aged 30.2 +/- 16.4 years), to a maximum extent of 10% of the body surface were evaluated 24 h after burn injury using RMCM. The following parameters were obtained using RMCM: stratum corneum thickness, epidermal thickness, basal layer thickness, granular cell size. RESULTS: Compared to the controls (12.8 +/- 2.5 microm), stratum corneum thickness decreased significantly to 10.6 +/- 2.1 microm in the TI group, whereas it increased significantly to 16.4 +/- 3.1 microm in the SB group. The epidermal thickness did not differ significantly in the TI group (47.9 +/- 2.3 microm) and SB group (49.1 +/- 3.5 microm); however, both increased significantly compared to their respective controls (41.8 +/- 1.4 microm). The basal layer thickness increased more in the SB group compared to the TI group (17.9 +/- 1.4 microm vs. 15.6 +/- 1.1 microm). Both differed also significantly compared to their controls (13.8 +/- 0.9 microm). The granular cell size increased significantly in both groups compared to the controls (731 +/- 42 microm); however, a significantly higher increase was observed in the TI group (852 +/- 58 microm) compared to the SB group (784 +/- 61 microm). CONCLUSIONS: Ultraviolet radiation seems to influence predominantly deeper epidermal layers, whereas heat-induced burns affect more superficial epidermal layers. The term 'First-degree burn' should not be used synonymously for sunburn and superficial thermal burn injuries. Conflicts of interest None declared.

In vivo reflectance-mode confocal microscopy provides insights in human skin microcirculation and histomorphology.

PURPOSE: Various approaches are used to study microcirculation, however, no modality evaluates microcirculation and histomorphology on cellular levels. We hypothesized that reflectance-mode confocal microscopy (RCM) enables simultaneous evaluation in vivo of both microcirculation and histomorphology. PRINCIPALS: The forearm of 20 volunteers was exposed to either local heat stress (HS-group), or to local cold stress (CS-group). RCM was performed prior and after temperature stress to evaluate quantitative blood-cell flow, capillary loop diameter, granular cell size, and basal layer thickness. RESULTS: In the HS-group, we observed significant increase in capillary loop diameter and increased blood-cell flow after heat stress. In the CS-group, significant decreases of capillary loop diameter and in blood-cell flow were determined following cold stress. Granular cell size and basal layer thickness differed insignificantly prior and after local temperature stress. CONCLUSIONS: RCM provides real-time and in vivo high resolution imaging of temperature-dependent changes in the human skin microcirculation and histomorphology on cellular levels.

Long-term results and the Disabilities of the Arm, Shoulder, and Hand score analysis after modified Brooks and D'Aubigne tendon transfer for radial nerve palsy.

PURPOSE: Radial nerve damage results in substantial functional limitations of the upper extremity. No detailed data exist regarding long-term results, patient satisfaction, and professional and social reintegration after tendon transfer for irreparable damage to the radial nerve. In this retrospective study, we investigated these data through the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire. METHODS: Between 1995 and 2006, 77 patients underwent a modified Brooks and d'Aubigne surgical technique for radial nerve palsy in our department. In 19 cases, the flexor carpi radialis muscle was used as a donor instead of the flexor carpi ulnaris muscle. The mean follow-up period was 60 months (range, 24-150 months); motion of the wrist and finger joints and pinch-grip power were compared with the healthy side. We assessed the limitation in pursuing daily activities using the DASH score. RESULTS: Wrist extension averaged 73% of the contralateral side, whereas the value for movement of digital extension was 32% and for thumb abduction in the palmar direction it was 80%. The power grip was reduced to 49% and the pinch grip was reduced to 28%. The mean DASH score was 15 +/- 9, the symptom score mean was 15 +/- 7, and the working score mean was 12 +/- 10. The mean total DASH score was 16 +/- 10. The proportion of patients who remained employed after surgical treatment was 89%. CONCLUSIONS: Functional results, adequate patient satisfaction, and sufficient professional and social reintegration can be achieved after modified Brooks and d'Aubigne tendon transfer. Accordingly, the tendon transfer offers an important alternative-possibly the procedure of choice-to microsurgical nerve reconstruction, particularly when early professional and social reintegration is important.

Differentiation of superficial-partial vs. deep-partial thickness burn injuries in vivo by confocal-laser-scanning microscopy.

OBJECTIVE: The current determination of burn depth is based both on a visual and clinical assessment. Confocal-laser-scanning microscopy (CLSM) enables in vivo histomorphological images. We hypothesized that CLSM can differentiate superficial-partial vs. deep-partial thickness burns on a histomorphological level. METHODS: Thirty-eight burn wounds in 14 patients were clinically divided in three groups from superficial (group 1), superficial-partial (group 2) to deep-partial (group 3) thickness burns. CLSM was performed with the Vivascope 1500 (Lucid Inc., Rochester, NY, USA) 24h after burn. The following parameters were assessed: cell size of the granular-layer, thickness of the basal-layer, minimal thickness of the epidermis and number of perfused dermal papillae. RESULTS: Superficial burns resulted in a significant increase of the cell size of the granular-layer and a higher increase of the minimal thickness of the epidermis as in superficial-partial thickness burns. The granular-layer in partial thickness burns was destroyed. Superficial burns had an increased thickness of the basal-layer; in superficial-partial thickness burns the basal-layer was partly destroyed with complete destruction in deep-partial thickness burns. In superficial burns the perfused dermal papillae were increased significantly, while decreased in superficial-partial thickness, and completely destroyed in deep-partial thickness burns up to a depth of 350 microm. CONCLUSIONS: In vivo confocal-laser-scanning microscopy can differentiate superficial-partial vs. deep-partial thickness burns on a histomorphological level.