Duplex ultrasonography scanning for chronic venous disease: patterns of venous reflux

PURPOSE

Patterns of flow in superficial and deep veins and outward flow in medial calf perforators were studied by duplex ultrasonography scanning in 1653 lower limbs in 1114 consecutive patients. This study compares results in 776 limbs with primary uncomplicated varicose veins with those in 166 limbs with the complications of lipodermatosclerosis or past venous ulceration.

METHODS

Duplex scanning determined whether superficial and deep veins were occluded or showed reflux and whether outward flow occurred in medial calf perforators with calf muscle contraction.

RESULTS

Two proximal deep veins were occluded. When limbs with primary uncomplicated varicose veins, lipodermatosclerosis, or past ulceration were compared, superficial reflux alone was seen in 55%, 39%, and 38%, deep reflux alone was seen in 2%, 7%, and 8%, and combined superficial and deep reflux was seen in 18%, 34%, and 48%, respectively. Superficial reflux affected the long saphenous system alone in 58%, 57%, and 40%, the short saphenous system alone in 18%, 18%, and 26%, and both the long and short saphenous systems in 24%, 25%, and 34%, respectively. Limbs with ulceration more frequently showed superficial reflux (p < 0.05), and all limbs with complications more frequently showed short saphenous reflux (p < 0.05) and deep reflux (p < 0.01) specifically in the posterior tibial veins (p < 0.01). Outward flow was seen in medial calf perforators in 57%, 67%, and 66%, respectively; it occurred more frequently in all limbs with complications (p < 0.05). Isolated outward flow in perforators without superficial or deep reflux was seen in 10%, 10%, and 2%, respectively.

CONCLUSIONS

Most limbs with complications had superficial reflux either alone or combined with deep reflux, and few had deep reflux alone. Reflux was more frequent in posterior tibial veins for limbs with complications compared with those with uncomplicated primary varicose veins. Outward flow in perforators was common in limbs with complications and with uncomplicated primary varicose veins, but isolated outward flow in perforators was uncommon. Treatment directed to the superficial veins alone may be sufficient for most patients with complications.

[Immunological reactivity and the hypophyseal-ovarian system in patients with circumscribed scleroderma]

Immune responsiveness and functional activity of hypophyseal-gonadal system were studied in 30 women of childbearing age presenting with circumscribed scleroderma. The findings obtained are consistent with a clinical picture of immunity T-system deficiency suggesting a role for T-lymphocyte subpopulations in derangement of immune regulation. Alterations in hormonal homeostasis were manifested by hypoestrogenia and imbalance of gonadotrophic hormones. Relationship of sex hormones to indices for cell-mediated immunity is discussed as is their role in the pathogenesis of this medical condition.

Dermal oedema in lipodermatosclerosis: distribution, effects of posture and compressive theraphy evaluated by high-frequency ultrasonography

Although leg oedema is believed to contribute to the pathogenesis of lipodermatosclerosis and leg ulcer, little is known about the cutaneous distribution of water in lipodermatosclerosis. In lipodermatosclerosis accompanied by leg ulceration, a subepidermal low echogenic band is seen in the high-frequency echograms of the skin at the boundary of the wound. Since skin echogenicity is inversely related to the amount of water contained, it has been assumed that the subepidermal low echogenic band corresponds to oedema in the papillary dermis. In this study we evaluated dermal oedema in lipodermatosclerosis by quantifying changes of skin echogenicity in 20 patients with lipodermatosclerosis and 20 age- and sex-matched controls. In order for us to evaluate the influence of the upright posture on skin water content, echogenicity was determined three times a day in various regions of the lower and upper extremities. Next morning, after ultrasound examination of the ankle skin, a compressive stocking was applied for 12 h and then the measurements of echogenicity were repeated. At any time of the day, ankle and calf skin was less echogenic in lipodermatosclerosis than in the control. The low echogenic area was confined to the subepidermal region. During the day the low echogenic area expanded in patients with lipodermatosclerosis. This phenomenon was reversed by leg compression. These results indicate that in lipodermatosclerosis oedema is located mainly in the papillary skin. An upright position causes aggravation of oedema, whereas application of compression protects against accumulation of water in the skin during the day.

Diabetic sclerodactyly

Sclerodactyly is a chronic skin disorder seen together with long-term degenerative microvascular complications of diabetes mellitus. In this study, the relationship between sclerodactyly and various clinical and laboratory characteristics of diabetes mellitus have been investigated. One hundred and forty-two diabetic patients (63 type 1 and 79 type 2) and 72 healthy controls were evaluated clinically. Among the 142 diabetic patients, skin biopsies were taken from 21; 38 underwent soft tissue X-ray examination and 78 underwent periungual capillaroscopy. Among the healthy controls those with sclerodactyly were on the average 12 years older than those without (T: 3.38; P < 0.01). On the other hand, among the patients with either type 1 or type 2 diabetes mellitus the ages were similar between those with and without sclerodactyly. There were no statistically significant differences in the prevalence of diabetic complications. The presence of complications, increased proximal nail fold capillarity, HbA1c levels, radiological and histopathological findings were not different among those patients who had or did not have sclerodactyly.

Sample size calculations in scleroderma: a rational approach to choosing outcome measurements in scleroderma trials

Subjects with both diffuse and limited scleroderma were studied to calculate the baseline characteristics of several commonly used outcome measurements in order to provide parameters for sample size calculations for scleroderma clinical trials. From these estimates, outcome measurements were chosen as potentially responsive to change in clinical trials if their sample sizes were not prohibitively large. Forty-five patients with scleroderma were systematically assessed to determine the means and standard deviations whereby sample size calculations can be performed using this information. Examples of sample sizes were determined for the entire group, and for 2 subsets: those with diffuse scleroderma and those with diffuse disease of recent onset. Many baseline characteristics were significantly different in patients with diffuse compared to limited systemic sclerosis. The baseline values were different for the Health Assessment Questionnaire (HAQ) disability score, Functional Index, grip strength, oral aperture, finger-to-palm distance, skin score, and physician global assessment. Sample sizes can vary widely depending upon the outcome measurement chosen and the range of deltas used within the different scleroderma subsets. Sample size requirements for many outcome measures are extremely large due to marked variability in the baseline measures. Primary outcome measures in scleroderma trials should be chosen which have adequate power to detect a minimal clinically relevant change in the primary outcome measurements at the sample sizes employed. All other outcome measures should be ranked as secondary. Skin scores, global assessments, and grip strength measurements require smaller sample sizes than the other outcome measurements which were studied. Sample sizes in future trials will vary depending upon the proportion of patients with diffuse and limited scleroderma who are included.

Effects of calcitriol on fibroblasts derived from skin of scleroderma patients

BACKGROUND

Scleroderma is a fibrotic disorder of unknown etiology that is characterized by excessive collagen synthesis and its deposition in the skin and various internal organs.

OBJECTIVE

To examine whether an overproduction of extracellular matrix molecules is a result of either increased fibroblast proliferation or increased collagen synthesis. As results of clinical trials with 1,25-dihydroxyvitamin D3 (calcitriol) have suggested beneficial effect in the treatment of scleroderma patients, the effects of calcitriol on fibroblasts derived from scleroderma and normal skin has been examined as well.

METHODS

Cultures of fibroblasts were established from biopsies from involved and uninvolved skin of scleroderma patients and from skin of healthy subjects, and compared with respect to proliferation, collagen synthesis and collagen lattice contraction.

RESULTS

No significant differences in cell proliferation and in the extent of fibroblast-induced collagen lattice contraction have been found between scleroderma patients exhibited a disorganized growth pattern in a monolayer culture in contrast to normal fibroblasts. Collagen synthesis tends to be higher in scleroderma fibroblasts as compared with controls. Calcitriol exerted an antiproliferative and antisynthetic effect on fibroblasts, which, however, did not discriminate healthy fibroblasts from fibroblasts derived from involved or uninvolved scleroderma plaques.

CONCLUSIONS

Our findings suggest that collagen accumulation may not result from increased proliferation or altered dynamic properties of fibroblasts in a scleroderma lesion but from increased collagen biosynthesis. We additionally found that calcitriol does not selectively affect scleroderma fibroblasts.

Effect of leg elevation on the skin microcirculation in chronic venous insufficiency

PURPOSE

Leg elevation is advised in the treatment of venous disease associated with edema. We have used laser Doppler fluxmetry to assess the effects of leg elevation on the skin microcirculation.

METHODS

Fifteen patients with lipodermatosclerosis caused by chronic venous insufficiency and 15 control subjects were studied. Measurements were made from the liposclerotic skin of patients and 8 cm above the medial malleolus in control subjects. Laser Doppler flux, blood cell velocity, and concentration of moving blood cells were recorded with the subject lying in the supine position and after elevating the foot 30 cm above the heart level.

RESULTS

In subjects in the horizontal position, the resting laser Doppler flux was significantly higher in patients with lipodermatosclerosis than in control subjects (median difference 63 arbitrary units; 95% confidence interval: 36, 108). This difference was due to a higher concentration of moving blood cells in the patient group (median difference 6.5 arbitrary units; 95% confidence interval: 3.4, 9). The blood cell velocity was not statistically significant between the two groups. On leg elevation, there was a substantial increase in the laser Doppler flux in the patient group; the median percentage increase in flux was 45% (p < 0.01). This was due to an increase in blood cell velocity; the median percentage increase was 41% (p < 0.01). There was no corresponding change in the concentration of moving blood cells. The results in the control group showed a similar trend but have not reached statistical significance.

CONCLUSION

We conclude that limb elevation enhanced the microcirculatory flow velocity in liposclerotic skin of patients with chronic venous insufficiency.

Treatment of linear localized scleroderma with the anti-allergic drug, tranilast

A 14-year-old boy with linear localized scleroderma had a dramatic improvement in contractures after treatment with N-(3',4'-dimethoxycinnamoyl) anthranilic acid (tranilast, Rizaben). The observation that this anti-allergic drug was effective in localized scleroderma lends further support to the concept that mast cells play a role in increased collagen synthesis in this disease.

Internal involvement in localized scleroderma

We studied 76 consecutive patients with localized scleroderma (morphea with or without linear scleroderma) and analyzed the frequency, prognosis, and predictors of internal involvement in a subset of 53 patients systematically investigated for the presence of such involvement. Internal involvement was found by systematic examination in 16 patients. Only 2 of them, including 1 patient who developed systemic scleroderma, had symptomatic and severe visceral disease. The other 14 patients had asymptomatic and minor abnormalities consisting of abnormal lower sphincter pressure, and/or peristaltic failure in the esophagus and slightly impaired carbon monoxide diffusion in the lung. Frequent seroimmunologic abnormalities had no predictive value. Three parameters were found to be associated with internal involvement: male gender (p < 0.05), increasing number of plaque-like lesions (p = 0.02) and hypergamma-globulinemia at 1st examination (p < 0.005). Mild esophageal and pulmonary involvement are not rare in morphea but are usually silent. In our series, after a median follow-up of 48 months, such involvement did not impair the prognosis. The mildness of these visceral abnormalities suggests that they do not justify routine detection in asymptomatic patients. Morphea and systemic scleroderma behave as 2 different diseases.

Microangiopathy of the skin and the effect of leg compression in patients with chronic venous insufficiency

PURPOSE

The reasons for the efficacy of leg compression in the treatment of chronic venous insufficiency are not clear. We have used laser Doppler fluxmetry to assess the effect of external compression on the skin microcirculation.

METHODS

Fifteen patients with lipodermatosclerosis caused by chronic venous insufficiency and 15 control subjects were studied in the supine and sitting positions. The laser Doppler probe, incorporated in a polyethylene chamber, was applied to the lower leg underneath a blood pressure cuff. Pressures were applied from 10 to 100 mm Hg in increments of 10 mm Hg. A computer data logging system recorded laser Doppler flux blood cell velocity, and concentration of moving blood cells.

RESULTS

In patients in the supine position, 20 mm Hg compression resulted in a median increase of 33% in laser Doppler flux, and a median increase of 79% in blood cell velocity, but higher pressures caused a progressive decrease in laser Doppler flux and blood cell velocity. With the patient in the sitting position, compression up to 60 mm Hg caused an increase in laser Doppler flux (median percentage increase at 20 mm Hg compression 84%) and blood cell velocity (median percentage increase at 20 mm Hg compression 22%). At 20 mm Hg compression, the concentration of moving blood cells decreased in the supine position (median percentage fall 27%) but did not change significantly in the dependent position. The effects of compression in control subjects were similar to those in patients, but to a lesser degree.

CONCLUSION

Our study suggests that compression treatment may achieve part of its effect by causing an increase in the microcirculatory flow velocity.

Free flap valvular transplantation for refractory venous ulceration

PURPOSE

Nonoperative therapeutic approaches to chronic venous ulceration, although effective, often require prolonged dressing care and immobilization with leg elevation. Results of skin grafting, perforator ligation, and valve interpositions and reconstructions improve results of ulcer healing but have not uniformly prevented ulcer recurrence. Our hypothesis is that reconstruction of chronic venous ulcers by excision of the diseased tissue bed and replacement with a free flap containing multiple competent microvenous valves and a normal tissue microcirculation will result in long-term cure of these debilitated patients.

METHODS

Six patients with chronic venous insufficiency and recurrent ulceration (class 3) underwent excision of ulcers and surrounding liposclerotic tissue beds and reconstruction with fasciocutaneous free flaps (two bilateral). Preoperative and postoperative photoplethysmography was used to assess venous refilling times. Duplex scanning was performed to assess deep venous reflux.

RESULTS

There were no flap failures. Photoplethysmographic venous refilling times measured on flaps demonstrated significant immediate and long-term increases from preoperative values (all results +3 by Society of Vascular Surgery outcome grading). Long-term maintenance of tissue integrity is shown by absence of recurrent ulceration and no evidence of recurrent tissue lipodermatosclerosis in all flaps at follow-up (8 months to 7.5 years; mean 24 months). No recurrent lipodermatosclerosis was seen on flap biopsy at 2 and 7 years. Separate cadaveric injection studies, including scanning electron microscopy, revealed numerous microvenous valves directed toward the draining pedicle in the flaps used for reconstruction.

CONCLUSIONS

This is the first comprehensive report providing combined laboratory and clinical evaluation, anatomic rationale, and long-term outcome of surgical rehabilitation of patients with chronic venous ulceration who have undergone microsurgical flap reconstruction.

Genetic and immunological differences between Japanese patients with diffuse scleroderma and limited scleroderma

OBJECTIVE

To study the association between HLA-DR and scleroderma (SSc), subsets of SSc, and autoantibodies in SSc.

METHODS

HLA-DR antigens were determined in 45 Japanese patients with SSc. The association between HLA-DR and SSc, subsets of SSc, and autoantibodies was analyzed in 22 patients with SSc excluding mixed connective tissue disease (MCTD)/overlap syndrome (OL).

RESULTS

When the 20 patients with MCTD and 3 patients with OL were excluded from the original patient group, a significant increase of HLA-DR2 was observed (59 vs 29% of controls, p < 0.01). The frequency of DR2 increased to 69% in patients with diffuse SSc (p < 0.01). DR1, which was not found in diffuse SSc, was found in 2 of 9 patients with limited SSc. The frequency of DR2 was significantly higher in patients with antitopoisomerase I (10/12, 83%, p < 0.05). In contrast, DR1 was found only in 2 patients with anticentromere antibodies (ACA), and all 5 patients with ACA had no HLA-DR2 (p < 0.01).

CONCLUSION

Our results suggest that different HLA-DR markers may be associated with the production of distinct autoantibodies in diffuse SSc and limited SSc.

Central nervous system involvement and psychiatric manifestations in systemic sclerosis (scleroderma): clinical and neurophysiological evaluation

We evaluated central nervous system and psychiatric involvement in a clinical sample of 32 patients with systemic sclerosis (SSc) (scleroderma). All patients underwent clinical neurological examination. Electroencephalography (EEG) and visual evoked potentials (VEPs) were also recorded. Prominent central nervous system (CNS) or psychiatric symptoms were present in 5 patients (16%), including encephalopathy, psychosis, anxiety disorder, grand mal seizures and transient ischemic attack. In addition, abnormal VEPs were recorded from 5/32 patients (16%), suggesting optic neuropathy. EEGs were mainly normal or showed only slight, nonspecific changes. Primary CNS involvement in scleroderma, however, could not be shown in any of the 5 cases with neuropsychiatric symptoms. Our results suggest that neuropsychiatric symptoms in SSc are, if not coincidental, indirectly caused by internal organ involvement of SSc or by possible overlapping connective tissue diseases. On the other hand, optic neuropathy might be a primary complication of SSc.

Nonspecific motor disorder of the esophagus: a real disorder or a manometric curiosity?

BACKGROUND

Nonspecific esophageal motility disorder (NEMD) has become a catchall term to describe abnormal esophageal manometric findings that do not meet strict criteria for established esophageal motility disorders. The aim of this study was to determine whether NEMD is a real esophageal motility disorder characterized by impairment of its motor function or simply a manometric disturbance with no clinical consequences.

METHODS

Esophageal transit of liquid and semisolids was studied using radioscintigraphic techniques in 10 symptomatic patients with manometrically diagnosed NEMD, 26 healthy control subjects, and 40 disease control subjects. The disease controls included 24 patients with achalasia, 9 with scleroderma, and 7 with diffuse esophageal spasm.

RESULTS

Patients with NEMD had no impairment of liquid emptying compared with healthy controls. Liquid emptying was markedly delayed in patients with achalasia and scleroderma. However, semisolid emptying was markedly delayed in patients with NEMD compared with healthy controls (P < 0.001), and the extent of its delayed emptying was similar to that seen in patients with achalasia, scleroderma, and diffuse esophageal spasm.

CONCLUSIONS

NEMD is not a manometric curiosity but a disorder characterized by selective impairment of semisolid emptying.

Hyperaemic response in the skin microcirculation of patients with chronic venous insufficiency

The capacity of the microcirculation in the liposclerotic skin of patients with chronic venous insufficiency to vasodilate in response to pilocarpine electrophoresis was assessed using laser Doppler fluxmetry. Pilocarpine induces vasodilation by direct action on capillaries; other methods of vasodilatation, such as heating of the skin, act by a number of pathways including a neurogenic one. Thirty patients with lipodermatosclerosis and chronic venous insufficiency and 20 control subjects were studied. There was no difference in peak vasodilatation following pilocarpine electrophoresis in the two groups. The median (interquartile range) peak flux in patients was 665 (382-1025) units and in controls 765 (452-975) units (95 per cent confidence interval of difference--270 to 150 units, P = 0.5). This suggests that the capillaries in the liposclerotic skin of patients with chronic venous insufficiency have a normal capacity to vasodilate.

Juvenile-onset mixed connective tissue disease: longitudinal follow-up

To establish the symptoms and clinical course of juvenile-onset mixed connective tissue disease, we studied 14 patients, classified according the criteria of Kasukawa et al. The patient records were studied retrospectively and all patients were examined in a 1-day follow-up program. Systemic lupus erythematosus and polymyositis/dermatomyositis-like symptoms disappeared in time, whereas scleroderma-like symptoms (such as in the Raynaud phenomenon) and joint abnormalities persisted. Extensive limitation of joint function was found in four patients. At the time of follow-up, no active renal disease was found. Thrombocytopenia was still present in one of the three patients who had had this feature. All patients had abnormalities of esophageal motility. Long-term corticosteroid treatment was associated with aseptic bone necrosis in three patients and growth retardation in one. We conclude that the Kasukawa criteria are easy to apply to children, and that juvenile-onset mixed connective tissue disease has many similarities to the adult form of the disease.

Oral-facial characteristics of circumscribed scleroderma: case report

Scleroderma is a rare disorder of unknown etiology. Circumscribed scleroderma is a localized focal form. It may present as well defined elevated or depressed white or yellowish patches termed "morphea," or linear bands made up of a furrow with elevated ridges on the margins described as "coup de sabre." The oral-facial characteristics of circumscribed scleroderma in a ten year old afflicted female are described in detail.

[An electro- and vectorcardiographic study of ventricular activation in scleroderma]

Electrical ventricular activation was studied by means of electrocardiogram and vectorcardiogram in 62 patients, 55 women and 7 men, affected by systemic sclerosis of average disease duration of 10.3 years. 45% of the patients showed the "diffused form" of the disease and 55% the "limited form". The vectorcardiogram showed some alterations of the ventricular activation in 55% of the recorded cases. The previous electrocardiogram found only 18%. The alterations, which are more frequent in the diffuse form than in the limited one, are the presence of loss of forces in septal, lateral or inferior or combined areas and intraventricular conduction disorders as complete and incomplete right bundle branch block, left anterior subdivision block, left posterior subdivision block, or combination between incomplete right bundle branch block and left anterior or posterior subdivision block. The vectorcardiogram was more sensitive than the electrocardiogram in showing loss of forces, also in patients with the limited form of systemic sclerosis, when the electrocardiogram was normal. Moreover the vectorcardiogram is helpful to identify left posterior subdivision block. The vectorcardiographic investigation seems to be a useful complement of the electrocardiogram especially for the identification of cases with myocardial involvement that is clinically silent.

Sympathetic skin response in scleroderma

Examination of the sympathetic skin response (SSR) was performed in 32 patients with systemic sclerosis, morphea and mixed connective tissue disease displaying scleroderma-like features. The control group consisted of 26 healthy subjects and 12 patients with other skin diseases and asymmetrical cutaneous changes. Right and left median and tibial nerves were stimulated successively and the responses were recorded from the palms and soles simultaneously. SSR abnormalities (delayed latency, decrease and/or asymmetry of amplitude, absent response) were observed in 68.8% of the patients, most frequently in linear scleroderma. An amplitude asymmetry of the responses from upper extremities was the most characteristic pattern of abnormalities. There was no correlation between the SSR and the localization, degree and character (inclurated oedema, atrophy, sclerosis) of skin changes, the duration of the disease, symptoms of the disorder of the autonomic nervous system symptoms (vasomotor and/or sudomotor) and the changes in capillaroscopy. All patients with slow motor conduction and sensor conduction velocities (MCV and SCV) had lower SSR amplitude and the patients with prolonged skin sensory chronaxy had more often delayed latency. The results revealed presence of disturbances of the autonomic nervous system in all varieties of scleroderma, both systemic and localized forms, even without any other signs of autonomic dysfunction.

Radionuclide esophageal transit studies in progressive systemic sclerosis: an analysis of longitudinal data

Nineteen patients with progressive systemic sclerosis (PSS) were studied by radionuclide esophageal transit (ET) and followed longitudinally for 3 to 5 years. Results were expressed as percent retention at 20 s and 10 min. There was gradual deterioration of ET at both 20 s and 10 min. When results were grouped into quartiles, deterioration occurred in 58.5% of followup studies in patients who initially had potential to deteriorate regarding 20 s retention and in 48% of similar patients regarding 10 min retention.

Facial reconstruction consideration in rheumatic diseases

In conclusion, the management of facial involvement in JRA, Romberg disease, and scleroderma is dictated by the degree of severity of the disease, age of onset, and length of activity. Functional occlusal abnormalities are best addressed through a team approach consisting of initial orthodontics followed by orthognathic surgery if needed. In all types of scleroderma, surgical facial reconstruction is best delayed until the disease is quiescent for at least a year. The ideal option for facial skeletal and soft-tissue augmentation has not yet been realized. Careful surgical planning and choice of grafts, flaps, or implants are critical to obtain the desired result.

Systemic lupus erythematosus, dermatomyositis, scleroderma, vasculopathies, and other connective tissue disorders in children

The diverse disorders discussed in this review share the underlying features of multisystem involvement and vasculitis as a part of their pathophysiology. A review of morbidity seen in childhood-onset systemic lupus erythematosus reveals the need for careful monitoring for complications secondary to treatment and infections. Current understanding of the pathophysiology and risks of developing the neonatal lupus syndrome are reviewed, with the important recognition of the association of specific maternal autoantibodies with affected offspring. A review of current management issues in the treatment of juvenile dermatomyositis is discussed. Kawasaki disease, one of the most common childhood vasculitides, continues to provoke interest in the areas of accurate diagnosis, potential etiologic role of common viruses, management, and late morbidity. Interesting case reports of children with unusual features of the more rarely described disorders of Sjögren's syndrome, scleroderma, and Behçet's syndrome are discussed.

The scleroderma-like syndrome of insulin-dependent diabetes mellitus

The scleroderma-like syndrome (SLS) of diabetes consists of limited joint mobility and digital sclerosis. It is described in 8-50% of insulin-dependent diabetes mellitus patients and is the earliest clinically apparent long-term complication of diabetes in children and adolescents. The frequency of this finding appears to be related to the duration of diabetes and increasing age. Less clear are the relationships between this syndrome and glycaemic control or genetic factors. SLS is an easily identifiable marker for those young patients who may be at increased risk for the development of early microvascular complications. Recognition of this characterization will permit the clinician to focus on newer and improved techniques for long-term physiological control of the diabetes, in an attempt to prevent microvascular disease.

Vasodilatory capacity of the skin in venous disease and its relationship to transcutaneous oxygen tension

Low transcutaneous oxygen tension (Ptc,O2) values in the supramalleolar skin of patients with venous disease are often reported. This measurement involves heating the skin to 43 degrees C to cause maximum vasodilatation and is valid only if liposclerotic and normal skin can vasodilate to the same degree. Forty-four limbs were studied, 15 with lipodermatosclerosis (LDS), 14 with uncomplicated varicose veins, and 15 controls. A Ptc,O2 electrode was modified to incorporate a laser Doppler probe. Laser Doppler flux was measured in the supramalleolar skin before and after local heating to 43 degrees C and the relative increase in flux was measured. The Ptc,O2 was then measured at the same site and on the chest. Vasodilatory capacity was expressed as the ratio of peak:basal laser Doppler flow, and the Ptc,O2 was expressed as a leg:chest ratio. Median laser Doppler flow was higher in limbs with LDS (median 67 mV) than in normal limbs (median 40 mV) (P less than 0.03). Ptc,O2 was higher in control limbs (median ratio 0.94) than in limbs with LDS (median 0.53) (P less than 0.006). The microcirculation in LDS had less capacity to vasodilate after heating (median factor of increase 5.4) than normal skin (median factor of increase 12.3) (P less than 0.001). A simple regression analysis was performed on all pairs of data, and revealed a correlation between Ptc,O2 and vasodilatory capacity (r = 0.524, P less than 0.001). The results indicate that low Ptc,O2 levels in venous disease reflect an inability of the microcirculation to increase its flow in response to local heating; inferences about the oxygen content of liposclerotic skin at normal temperatures cannot be drawn using this technique.