Device For Objective Measurement Research Articles

Objective Skin Quality Assessment after Reconstructive Procedures for Facial Skin Defects.

Local random skin flaps and skin grafts are everyday surgical techniques used to reconstruct skin defects. Although their clinical advantages and disadvantages are well known, there are still uncertainties with respect to their long-term results. Hence, the aim of this study was to evaluate outcomes more than one-year post operatively using objective measurement devices. The study included 31 facial defects reconstructed with local random flap, 30 facial defects reconstructed with split-thickness skin grafts (STSGs) and 30 facial defects reconstructed with full-thickness skin grafts (FTSGs). Skin quality was objectively evaluated using MP6 noninvasive probes (Courage + Khazaka GmbH, Cologne, Germany), which measure melanin count, erythema, hydration, sebum, friction and transepidermal water loss. The results showed that there were no significant differences in melanin count, erythema, hydration, sebum level, friction value and transepidermal water loss (TEWL) between the site reconstructed with random local flaps and the same site on the healthy contralateral side of the face. However, both FTSGs and STSGs showed significantly higher levels in terms of TEWL and erythema, whereas the levels of hydration, sebum and friction were significantly lower compared to the healthy contralateral side. Moreover, STSGs resulted in a significant difference in melanin count. These findings imply that the complex pathophysiology of the wound-healing process possibly results in better skin-quality outcomes for random local flaps than skin autografts. Consequently, this suggests that random local flaps should be implemented whenever possible for the reconstruction of facial region defects.

Sleep disturbance in elderly patients with dementia at home and the factors associated with its identification: An observational study

The purpose of this study was to objectively quantify the sleep of elderly patients with dementia at home using a device and to investigate the factors associated with its identification. Sixteen patients (6 males [37.5%], 84.1±4.7 years old; and 10 patients with mild dementia [62.5%]) and their family caregivers who were using outpatient memory clinics and home-visiting nursing station in Japan were included. Demographic and clinical data of the patients and their family caregivers, subjective perceptions of patients' sleep, family caregivers' Zarit care burden, and whether or not they were aware of patients' sleep problems were determined. Nighttime sleep parameters were collected for one week using a non-wearable actigraph. Sleep parameters were compared with patients' subjective views and family caregivers' observations to investigate factors indicative of sleep disturbance. Nighttime sleep parameters for 1 week (mean) were follows: sleep efficiency, 77.2%±9.3%; asleep time, 442.3±99.9 minutes; sleep latency, 18.2±15.8 minutes; awake time, 105.1±69.7 minutes; and number of times leaving the bed, 4.6±3.8 (maximum of 29/night). A significant positive correlation was found between sleep efficiency and duration of dementia (r=0.53, p=0.046), while no correlation was found with dementia severity or Zarit care burden score. The agreement between the patients' complaints about sleep and sleep efficiency (75%) was 30.7%, and family caregivers' awareness of patients' nighttime awakening and bed-leaving was significantly associated with patients' incontinence (p=0.024) and a greater dementia severity (p=0.027). Elderly dementia patients experienced sleep disturbance at home, such as nighttime awakening and associated bed-leaving; however, it might be difficult to identify these patients at an early stage based on their own complaints and observations by family caregivers. Identifying sleep problems at an early stage may thus require the use of objective measurement devices.

Novel technology at hand to measure skin hydration by Biodisplay smartphone touch screen panel

Skin hydration is generally evaluated using devices that measure capacitance or conductance. A new technology (Biodisplay) was developed to provide accurate measurements of skin hydration at the contact site. This study aimed to test the reliability of the Biodisplay by comparing its performance results with those of similar devices currently used to objectively assess skin hydration. For each of the 30 participants, skin hydration was measured at each of the defined points on the forearm three times using the Biodisplay and a Hydration probe (HP), an objective measurement device of skin hydration. We also evaluated skin hydration of the arm using both tools after applying moisturizers to evaluate interferences from skin care products. The reliability and reproducibility of each device were analyzed by intraclass correlation coefficients (ICC), and the correlation of the two devices was evaluated by Pearson’s correlation coefficients (PCC). The Biodisplay demonstrated moderate-to-excellent reliability (ICC: (0.741–0.980)), but lower reliability than the HP (ICC: (0.953–0.980)). The skin hydration measurements made by the two devices were demonstrated to be significantly correlated, showing moderate correlations (PCC: 0.601). The Biodisplay can provide reasonably reliable and accurate measurements for skin hydration with the strong points of portability and accessibility.

Wrinkle sign for the Silfverskiöld test

Shortening of the triceps surae is evaluated using the Silfverskiöld test. The increase in dorsiflexion with the knee in flexion compared to the knee in extension makes the test positive. To perform the test, the examiner uses both hands and is not able to hold any device for objective measurement while assessing the magnitude of dorsiflexion. In view of this obstacle, this paper aims to describe a tip of a physical examination technique for evaluating the shortening of the triceps surae through the evaluation of the anterior wrinkle of the ankle. We performed the technique in a patient with shortening of the gastrocnemius and recorded the test, showing an increase in the anterior skinfold of the ankle. The test is simple, reproducible, requires no additional apparatus and shows variety in the severity of shortening. Level of Evidence V; Therapeutic Studies; Expert Opinion.

Burns objective scar scale (BOSS): Validation of an objective measurement devices based burn scar scale panel

AimsHypertrophic scars in burn survivors are a major cause of morbidity but the development of evidence based treatments is hampered by the lack of objective measurements of these scars. The objective of our study is to investigate the most accurate parameters for objective scar assessment and to create a combination score to facilitate the use of a panel of objective scar measurement tools. MethodsThree independent assessors evaluated fifty five scar sites on fifty five burn patients with both the subjective modified Vancouver Scar Scale (mVSS) and a panel of objective measurement tools including the DSM II Colormeter, Cutometer, Dermascan high frequency ultrasound. The sensitivity and specificity of the objective scar parameters in predicting a mVSS score of 6 or more using the Receiving Operator Characteristic Area under the curve (ROC AUC) was then calculated and the most accurate parameters were combined to create an objective global scar score. ResultsThe ROC AUC values were found to be highest for the Dermascan scar thickness (0.897), dermal intensity and intensity ratio (0.914 and 0.919), Cutometer R0 value (0.942), and R0 ratio (0.944). For colour measurements, ratios of scar to normal skin performed better than the single parameters for both erythema and pigmentation measurements: DSM II Erythema ratio vs Erythema (0.885 vs 0.818), DSM II a* ratio vs a* (0.848 vs 0.741); DSM II Melanin ratio vs Melanin (0.854 vs 0.761), DSM II L* ratio vs L* (0.862 vs 0.767). Analysis of the ROC AUC with chi-square test values showed that the highest AUC (0.786) was obtained with the combination of the Cutometer R0, Dermascan scar thickness, intensity and their respective scar to normal skin ratios. A total score of 5 and above (out of 6 parameters) had the highest combined sensitivity (69.0%) and specificity (83.3%). ConclusionThe objective parameters for the DSM II Colormeter, Cutometer and Dermascan high frequency ultrasound were all found to have moderate to strong ROC AUC values and combination of the Cutometer R0 and Dermascan scar thickness and intensity values can be used to create an objective global scar scale that can accurately differentiate patients with hypertrophic burn scarring from non-hypertrophic scars or normal skin.

Estimation of partitioning of airflow in septal surgery: A prospective study with reference to the NOSE scale.

Improper patient selection for septal surgery often has been found to result in therapeutic failure, and there needs to be an objective assessment of nasal obstruction before the surgery and for postoperative follow-up that can be applied in the routine otolaryngology practice. The purpose of this study is to assess the usefulness of a cost-effective device for objective measurement of the nasal airway partitioning in selecting patients for septal surgery and for postoperative outcome evaluation. A hospital-based, prospective, observational study was carried out in a tertiary-care teaching institution involving 74 patients waiting for septal surgery. Each patient was exposed to subjective assessment of nasal obstruction by the Nasal Obstruction Symptom Evaluation (NOSE) scale and objective measurement by Nasal Partitioning Ratio (NPR) using a new device, Nasal Airway Partition Meter (NAPM), once before and twice after surgery. Overall, average NOSE score and NPR values were 66.42 ± 9.42 and 0.57 ± 0.18, respectively, at preoperative assessment (correlation coefficient 0.441). Sixty of the 74 patients had high values for both NPR and NOSE scores (Group 1), but in the remaining 14, NPR values were found to be lower despite high NOSE scores (Group 2). Postsurgery, the NOSE score and NPR values were significantly reduced in Group 1. In contrast, participants in Group 2 showed no alteration in the values of both the parameters after the same operative maneuver. However, 2 patients in Group 1 had NOSE score and NPR values unaltered, while 1 patient in Group 2 had a reduced NOSE score after surgery. Therefore, the validity of the new equipment was calculated to be 96.7% sensitive and 92.9% specific to identify patients who needed to undergo septal surgery for their nasal obstruction. It can be deduced from the present study that NAPM can be a cost-effective device for clinicians to objectively measure nasal airway obstruction and screen patients for septal surgery.

Quantification of Nighttime Micturition With an Ambulatory Sensor-Based System.

Among elderly males, benign prostate syndrome (BPS) is the most common urinary disorder. Nocturia is one of the major symptoms of BPS and has a considerable influence on the quality of life. For assessment of BPS (including nocturia), the International Prostate Symptom Score is widely used, but questionnaires are prone to bias. To date, there is no objective measurement system available for nocturia. In this study, we present an unobtrusive and nonstigmatizing device for objective measurement of nighttime micturition. In a preliminary study of six males diagnosed with BPS and nighttime micturition ≥ 2×, we showed that the device is accurate, with an average misdetection rate of 0.32 events and a mean absolute deviation of 3.8% when comparing the average number of nighttime micturition occurrences. In this extended study, an additional nine males were recorded and data from an occupancy sensor were also included. The results of the preliminary study were confirmed with an average misdetection rate of 0.33 events and a mean absolute deviation of 9.1%. The system can, therefore, be used to objectively measure nighttime micturition and, thereby, provide the basis for treatment, e.g., medication efficacy assessment.

Physical activity assessment in the general population; instrumental methods and new technologies.

The objective measurement of human movement and the quantification of energy expenditure due to physical activity is an identified need in both research and the clinical setting. Validated and well-defined reference methods (double labelled water, direct calorimetry, indirect calorimetry) are expensive and mostly limited to the laboratory setting. Therefore, in the last years, several objective measurement devices have been developed which are appropriate for field studies and clinical settings. There is no gold standard among them, as all have limitations. Pedometers are small, non-expensive, count the steps taken and give information on total physical activity, but not about physical activity patterns and behaviour. Accelerometers are expensive, save information about frequency and intensity of physical activity, but not about type of physical activity. Both pedometers and accelerometers only save information about lower body movement, but reliability about the estimation of energy expenditure is limited. Heart rate monitoring relates intensity to energy expenditure, but gives no information about physical activity. GPS watches are portable, relatively inexpensive, non-invasive and provide distance, speed, and elevation with exact time and location, but are maybe limited for the assessment of brief higher speed movement and energy expenditure. Combined motion sensors combine accelerometry with the measurement of physiological variables and share advantages of single devices and are more precise. Manufacturer software which applies activity-specific algorithms for the calculation of energy expenditure can affect energy expenditure results. Most of the devices estimate energy expenditure more accurately at light to moderate intensities; underestimation increases at very light and higher intensity activities.

Abstract P128: A New Device for Objective Measurement of Sedentary Behavior

Objective measurement of sedentary behavior with accelerometers is an important part of epidemiological research. Unfortunately, the definition of sedentary behavior includes both “sitting and low levels of energy expenditure”, which are not usually measured by popular activity monitors. Currently, there is only one research device (ActivPAL) that can objectively measure both body posture and activity for sedentary behavior classification. The purpose of this study was to compare the Lumoback device, a commercial accelerometer-based posture monitor, for sedentary measurement during daily activities to the ActivPAL. The Lumoback also has real-time feedback delivered to the user through their mobile device, which may prove to be instrumental in sedentary intervention research. Subjects (N=33) wore the Lumoback and ActivPAL devices simultaneously during waking hours while continuing with their normal activity patterns. Linear regression showed good correlation between sitting minutes (R2=0.89, p < 0.001) and standing minutes (R2=0.86, p < 0.001) from the devices. There was no significant difference (p > 0.05) between the seconds of sedentary behavior measured with the lumoback and seconds sitting/lying measured with the ActivPAL. The lumoback posture monitor was similar to the ActivPAL for measurement of sedentary behavior, and could be used to measure sedentary behavior over the course of a waking day.

Reliability and Validity of the Multimedia Activity Recall in Children and Adults (MARCA) in People with Chronic Obstructive Pulmonary Disease

ObjectiveTo determine the reliability and validity of the Multimedia Activity Recall for Children and Adults (MARCA) in people with chronic obstructive pulmonary disease (COPD).DesignPeople with COPD and their carers completed the Multimedia Activity Recall for Children and Adults (MARCA) for four, 24-hour periods (including test-retest of 2 days) while wearing a triaxial accelerometer (Actigraph GT3X+®), a multi-sensor armband (Sensewear Pro3®) and a pedometer (New Lifestyles 1000®).SettingSelf reported activity recalls (MARCA) and objective activity monitoring (Accelerometry) were recorded under free-living conditions.Participants24 couples were included in the analysis (COPD; age 74.4±7.9 yrs, FEV1 54±13% Carer; age 69.6±10.9 yrs, FEV1 99±24%).InterventionsNot applicable.Main Outcome Measure(s)Test-retest reliability was compared for MARCA activity domains and different energy expenditure zones. Validity was assessed between MARCA-derived physical activity level (in metabolic equivalent of task (MET) per minute), duration of moderate to vigorous physical activity (min) and related data from the objective measurement devices. Analysis included intra-class correlation coefficients (ICC), Bland-Altman analyses, paired t-tests (p) and Spearman's rank correlation coefficients (rs).ResultsReliability between occasions of recall for all activity domains was uniformly high, with test-retest correlations consistently >0.9. Validity correlations were moderate to strong (rs = 0.43–0.80) across all comparisons. The MARCA yields comparable PAL estimates and slightly higher moderate to vigorous physical activity (MVPA) estimates.ConclusionIn older adults with chronic illness, the MARCA is a valid and reliable tool for capturing not only the time and energy expenditure associated with physical and sedentary activities but also information on the types of activities.

Abstract P145: Successful Use of Telephone and Mail for Obtaining Usable Accelerometer Data from a National Cohort: The Experience of the REasons for Geographic and Racial Differences in Stroke (REGARDS) Study

Background: Epidemiologic studies examining physical activity have used self-report or the preferred objective measurement devices of pedometers or accelerometers. NHANES 2003-2004 used remuneration, in-person and express mail methods to obtain accelerometer data from 7176 individuals with 4867 (68%) providing 4+ valid days of wear. Herein we describe the experience of another national epidemiologic study that used telephone and regular mail to obtain accelerometer data. Methods: This is an ancillary study to REGARDS, a national, population-based, longitudinal study of 30,239 blacks and whites, aged > 45 years, enrolled January 2003-October 2007. Participants were recruited from communities across all 48 of the lower United States, and include residents of 1,855 of the 3,033 US counties. Baseline evaluations were conducted through computer-assisted telephone interview (CATI), self-administered questionnaires, and an in-home visit. Participants are followed by CATI every 6 months. Starting with the May 2009 follow-up calls, contingent on availability of an accelerometer, participants were asked about willingness to wear an accelerometer for 7 days. Device inventory was 1150. Accelerometer, instructions, and stamped addressed envelope for return were mailed to consenting participants. Postcard acknowledgement, reminders, and < two calls were made to encourage compliance with wearing device and its return. Participants receive summary results but no financial compensation. Results: By August 23, 2012, 22 195 were asked in a CATI follow-up to participate; 52% initially consented, 17% deferred and will be recontacted, and 31% declined. Participation rates by race-sex groups were: WM 53%, WF 53%, BM 53%, BF 50%. Devices were shipped to 11,798 with a return rate of 92%; 935 are lost (outstanding > 120 days). Of accelerometers used/analyzed to date (n=9,422), 7819 (83%) provided 4+ valid days of wear, 434 (4.6%) had fewer than 4 valid days of wear, and 1,169 (12.4%) had incomplete/missing log sheet or device malfunction. The consenting-shipment-wearing-tracking-return-processing- and cleaning cycle is about 7-9 weeks per device, suggesting that approximately 6-7 participants can be evaluated per available device per year. Conclusions: A high yield of usable accelerometer data can be obtained from a national cohort through mail and telephone methods.

Physical dose of therapeutic exercises in institutional neck rehabilitation

To determine the intensity and volume of therapeutic exercises during a standard 13-day inpatient neck rehabilitation course in relation to overall physical activity in rehabilitation and everyday life. Cross-sectional study. Subjects (n = 19; 16 women and 3 men; mean age 48.6 years, standard deviation (SD) 6.6) with chronic non-specific neck pain were recruited from two inpatient neck rehabilitation courses. Intensity and volume of therapeutic exercises and physical activity were measured in metabolic equivalents (METs) with an objective measurement device and all-time recall questionnaire. Maximum oxygen uptake was determined in METs (METc) by direct maximal cycle ergometer. Subjects' mean METc was 7.2 METs (SD 1.4) or 25.3 ml/kg/min (SD 4.8). Intensity of all therapeutic exercises was 1.9 METs or 27 %METc (SD 5.1) and volume 7.7 MET-hours/week. Intensity of specific neck and shoulder exercises was 2.0 METs or 28 %METc (SD 5.4) and volume 2.5 MET-hours/week. In addition, subjects were more active in everyday life than in inpatient rehabilitation. The therapeutic exercise dose failed to reach previously reported target values for pain relief. The dose of therapeutic exercises and confounding physical activity should be carefully controlled in pain rehabilitation programmes.

Skin Parameter Map Retrieval from a Dedicated Multispectral Imaging System Applied to Dermatology/Cosmetology

In vivo quantitative assessment of skin lesions is an important step in the evaluation of skin condition. An objective measurement device can help as a valuable tool for skin analysis. We propose an explorative new multispectral camera specifically developed for dermatology/cosmetology applications. The multispectral imaging system provides images of skin reflectance at different wavebands covering visible and near-infrared domain. It is coupled with a neural network-based algorithm for the reconstruction of reflectance cube of cutaneous data. This cube contains only skin optical reflectance spectrum in each pixel of the bidimensional spatial information. The reflectance cube is analyzed by an algorithm based on a Kubelka-Munk model combined with evolutionary algorithm. The technique allows quantitative measure of cutaneous tissue and retrieves five skin parameter maps: melanin concentration, epidermis/dermis thickness, haemoglobin concentration, and the oxygenated hemoglobin. The results retrieved on healthy participants by the algorithm are in good accordance with the data from the literature. The usefulness of the developed technique was proved during two experiments: a clinical study based on vitiligo and melasma skin lesions and a skin oxygenation experiment (induced ischemia) with healthy participant where normal tissues are recorded at normal state and when temporary ischemia is induced.

Evaluierung der Wertigkeit objektiver und subjektiver Verfahren zur Messung von pseudophaker Akkommodation

The aim of this study was to compare the validity and plausibility of various subjective and objective measurement methods for evaluation of pseudophakic accommodation. Eye Clinic Bellevue, Kiel, Germany. A total of 21 patients were examined over an average period of 34 months (range 12-51 months) after implantation of a potentially accommodative, model 1CU intraocular lens (IOL, HumanOptics, Germany). The following subjective measurements were taken: near point measurement with the accommodometer (Clement Clarke, Harlow, UK), defocus curve and near visual acuity with far and near reading charts. The IOLMaster (Carl Zeiss Meditec, Germany), ACMaster (Carl Zeiss Meditec, Germany) and Shin-Nippon K 5001 AR (Shin-Nippon, Japan) were employed as objective measurement devices. With this devices information is obtained about the anterior chamber depth (ACD, preoperative and postoperative), the movement of the IOL and the refractive change of eyes during the accommodative process. Depending on the method utilized there were large variations of the examined IOL in relation to the extent of the measured accommodative effects in their entirety with the objective as well as the subjective measurement method. A differentiation of pseudophakic accommodation and pseudophakic pseudoaccommodation is not possible with the conventional measurement methods applied and examined in this study. Only the ACMaster is an objective method for measurement of the axial shift of an IOL. However, subjective measurement methods can only record the total of both accommodation portions but do not allow any scientifically-founded statement about the functional principle of a potentially accommodative IOL.

Objective measurement devices to assess static rotational knee laxity: focus on the Rotameter

The present article summarizes the development of a simple, objective, and non-invasive measurement device for tibiofemoral rotation to assess static rotational knee laxity. The device is based on the dial test with the patient lying prone and the knee flexed to 30°. From measurements of 30 healthy participants, the device achieved high inter- and intra-observer reliability and showed a high correlation of the measured results with the contralateral knees of the participants. Measurements of the device were also performed in a human cadaver study and revealed highly correlated results when compared to the simultaneous measurements of a knee navigation system, which was used as an invasive standard method to assess tibial rotation. In human cadaver specimens, it was shown that a simulated tear of the posterolateral bundle as well as a complete ACL tear led to a significant increase in isolated tibiofemoral rotation compared to the intact ACL. A retrospective case series investigated the clinical results as well as knee laxity measurements after ACL surgery in vivo. Rotational, as well as anteroposterior (AP), knee laxity was objectively assessed in 52 patients at a mean postoperative follow-up of 27months by comparing the measured results with the results of the contralateral unaffected knee in each patient. The clinical results were comparable to the results reported in the literature. Moreover, rotational laxity was successfully restored after ACL reconstruction, whereas AP laxity showed significant differences compared to the contralateral knees although they were defined as clinically successful according to the IKDC classification. A non-invasive and objective knee rotational measurement device has been developed, which offers good potential for objective quality control in knee ligament injuries and their treatment. Review article, Level IV.

Validation of mobile eye-tracking as novel and efficient means for differentiating progressive supranuclear palsy from Parkinson's disease

Background: The decreased ability to carry out vertical saccades is a key symptom of Progressive Supranuclear Palsy (PSP). Objective measurement devices can help to reliably detect subtle eye movement disturbances to improve sensitivity and specificity of the clinical diagnosis. The present study aims at transferring findings from restricted stationary video-oculography (VOG) to a wearable head-mounted device, which can be readily applied in clinical practice. Methods: We investigated the eye movements in 10 possible or probable PSP patients, 11 Parkinson's disease (PD) patients, and 10 age-matched healthy controls (HCs) using a mobile, gaze-driven video camera setup (EyeSeeCam). Ocular movements were analyzed during a standardized fixation protocol and in an unrestricted real-life scenario while walking along a corridor. Results: The EyeSeeCam detected prominent impairment of both saccade velocity and amplitude in PSP patients, differentiating them from PD and HCs. Differences were particularly evident for saccades in the vertical plane, and stronger for saccades than for other eye movements. Differences were more pronounced during the standardized protocol than in the real-life scenario. Conclusions: Combined analysis of saccade velocity and saccade amplitude during the fixation protocol with the EyeSeeCam provides a simple, rapid (<20 s), and reliable tool to differentiate clinically established PSP patients from PD and HCs. As such, our findings prepare the ground for using wearable eye-tracking in patients with uncertain diagnoses.

Physical activity levels after limb salvage surgery are not related to clinical scores—objective activity assessment in 22 patients after malignant bone tumor treatment with modular prostheses

The aim of the present study was to objectively assess the physical activity levels of patients after tumor prosthesis implantation with two objective measurement devices. The DynaPort ADL monitor permitted up to 24 hr monitoring of lower-extremity physical activities in daily life with respect to posture and locomotion. The step activity monitor (SAM) was worn for a whole week to collect the daily number of gait cycles. The devices were worn during the waking hours by 22 patients with knee prostheses after wide tumor resection. In the MSTS and TESS scores the patients achieved over 80% of the maximum score indicating a good clinical outcome. The most prominent activity was sitting which accounted for 54 +/- 18% of the recorded time, followed by standing (27 +/- 16%), locomotion (10 +/- 6%), and lying (8 +/- 6%). During locomotion, the average walking activity accumulated to 4,786 +/- 1,770 step cycles per day (range 2,045-8,135) corresponding to a yearly 1.75 million steps. There was no significant correlation between clinical scores and step count measures. Even though this activity level was lower than for a group of healthy adults it was comparable to the activity level for other patients, for example, with hip arthroplasty as reported in the literature.

“Urgency Tip”: A Portable Patient-Activated Device for Objective Measurement of Urinary Urgency

For clinical practice and research of overactive bladder syndrome, it is essential to evaluate urgency symptoms in daily life. We have developed a portable patient-activated device to record bladder sensations. This electronic device is pocket-size and light, with five grading buttons and another button for cancellation.

Diagnosis of chronic mesenteric ischemia by visible light spectroscopy during endoscopy

Chronic mesenteric ischemia can be difficult to diagnose by means of currently available clinical techniques. We developed a novel endoscopic device for objective measurement of GI mucosal ischemia. Our purpose was to evaluate the performance of the device in patients with chronic mesenteric ischemia. A fiberoptic catheter-based visible light spectroscopy oximeter (T-Stat 303 Microvascular Oximeter, Spectros, Portola Valley, Calif) was used to evaluate 30 healthy control subjects and 3 patients with chronic mesenteric ischemia before and after successful percutaneous stenting. Veterans Affairs Palo Alto Health Care System hospital. Normal mucosal (capillary) hemoglobin oxygen saturation was 60% to 73% in the duodenum and jejunum. In the 3 patients with chronic mesenteric ischemia, ischemic areas in the duodenum or proximal jejunum were found with mucosal saturations of 16% to 30%. After successful angioplasty and stent placement of the celiac, superior mesenteric, or inferior mesenteric arteries, the mucosal saturation in these areas increased to 51% to 60%. This preliminary study suggests that chronic mesenteric ischemia is detectable during endoscopy by use of visible light spectroscopy and that successful endovascular treatment results in near normalization of mucosal oxygen saturation.

Diagnosis of Chronic Mesenteric Ischemia By Visible Light Spectroscopy During Endoscopy

Background: Chronic mesenteric ischemia can be difficult to diagnose using currently available clinical technologies. We developed a novel endoscopic device for objective measurement of gastrointestinal mucosal ischemia. Objective: Evaluate the performance of the device in patients with chronic mesenteric ischemia. Design: A fiberoptic catheter based visible light spectroscopy oximeter (T-Stat 303 Microvascular Oximeter, Spectros Corporation) was used to evaluate thirty normal controls and three patients with chronic mesenteric ischemia before and after successful percutaneous stenting.