Feasibility of Breast Cancer Metastasis Assessment of Ex Vivo Sentinel Lymph Nodes through a p-H&E Optical Coherence Microscopic Imaging System.

Frozen-sectioned hematoxylin-eosin (H&E) image evaluation is the current method for intraoperative breast cancer metastasis assessment through ex vivo sentinel lymph nodes (SLNs). After frozen sectioning, the sliced fatty region of the frozen-sectioned specimen is easily dropped because of different freezing points for fatty tissues and other tissues. Optical-sectioned H&E images provide a nondestructive method for obtaining the insight en face image near the attached surface of the dissected specimen, preventing the freezing problem of fatty tissue. Specimens from 29 patients at Wanfang Hospital were collected after excision and were analyzed at the pathology laboratory, and a fluorescence-in-built optical coherence microscopic imaging system (OCMIS) was then used to visualize the pseudo-H&E (p-H&E) images of the SLNs for intraoperative breast cancer metastasis assessment, and the specificity, sensitivity, and accuracy were 100%, 88.9%, and 98.8% (n = 83), respectively. Compared with gold-standard paraffin-sectioned H&E images, the specificity, sensitivity, and accuracy obtained with the frozen-sectioned H&E images (n = 85) of the specimens were the same as those obtained with the p-H&E images (n = 95). Thus, OCMIS is a useful noninvasive image-assisted tool for breast cancer metastasis assessment based on SLN images.

Rapid pseudo-H&E imaging using a fluorescence-inbuilt optical coherence microscopic imaging system.

A technique using Linnik-based optical coherence microscopy (OCM), with built-in fluorescence microscopy (FM), is demonstrated here to describe cellular-level morphology for fresh porcine and biobank tissue specimens. The proposed method utilizes color-coding to generate digital pseudo-H&E (p-H&E) images. Using the same camera, colocalized FM images are merged with corresponding morphological OCM images using a 24-bit RGB composition process to generate position-matched p-H&E images. From receipt of dissected fresh tissue piece to generation of stitched images, the total processing time is <15 min for a 1-cm2 specimen, which is on average two times faster than frozen-section H&E process for fatty or water-rich fresh tissue specimens. This technique was successfully used to scan human and animal fresh tissue pieces, demonstrating its applicability for both biobank and veterinary purposes. We provide an in-depth comparison between p-H&E and human frozen-section H&E images acquired from the same metastatic sentinel lymph node slice (∼10 µm thick), and show the differences, like elastic fibers of a tiny blood vessel and cytoplasm of tumor cells. This optical sectioning technique provides histopathologists with a convenient assessment method that outputs large-field H&E-like images of fresh tissue pieces without requiring any physical embedment.

Segmentation of nucleus and cytoplasm of a single cell in three-dimensional tomogram using optical coherence tomography.

A random rayburst sampling (RRBS) framework was developed to detect the nucleus and cell membrane boundaries in three-dimensional (3-D) space. Raw images were acquired through a full-field optical coherence tomography system with submicron resolution­i.e., 0.8 ?? ? m in lateral and 0.9 ?? ? m in axial directions. The near-isometric resolution enables 3-D segmentation of a nucleus and cell membrane for determining the volumetric nuclear-to-cytoplasmic (N/C) ratio of a single cell. The RRBS framework was insensitive to the selection of seeds and image pixel noise. The robustness of the RRBS framework was verified through the convergence of the N/C ratio searching algorithm. The relative standard deviation of the N/C ratio between different randomly selected seed sets was only 2%. This technique is useful for various in vitro assays on single-cell analyses.

Full-depth epidermis tomography using a Mirau-based full-field optical coherence tomography.

With a Gaussian-like broadband light source from high brightness Ce(3+):YAG single-clad crystal fiber, a full-field optical coherence tomography using a home-designed Mirau objective realized high quality images of in vivo and excised skin tissues. With a 40 × silicone-oil-immersion Mirau objective, the achieved spatial resolutions in axial and lateral directions were 0.9 and 0.51 µm, respectively. Such a high spatial resolution enables the separation of lamellar structure of the full epidermis in both the cross-sectional and en face planes. The number of layers of stratum corneum and its thickness were quantitatively measured. This label free and non-invasive optical probe could be useful for evaluating the water barrier of skin tissue in clinics. As a preliminary in vivo experiment, the blood vessel in dermis was also observed, and the flowing of the red blood cells and location of the melanocyte were traced.

Non-invasive characterization of the domain boundary and structure properties of periodically poled ferroelectrics.

Shaping the ferroelectric domains as waveguide, grating, lens, and prism are key to the successful penetration of periodically-poled ferroelectrics on various wavelength conversion applications. The complicated structures are, however, difficult to be fully characterized, especially the unexpected index contrast at the anti-parallel domain boundaries are typical in the order of 10(-4) or less. An ultrahigh resolution optical coherence tomography was employed to fully characterize the domain boundary and structure properties of a periodically-poled lithium niobate (PPLN) waveguide with an axial resolution of 0.68 µm, an transversal resolution of 3.2 µm, and an index contrast sensitivity of 4x10(-7). The anti-parallel domain uniformity can clearly be seen non-invasively. Dispersion of the ferroelectric material was also obtained from 500 to 750 nm.

Microstructural and microspectral characterization of a vertically aligned liquid crystal display panel.

The microstructural and microspectral characteristics of a vertically aligned liquid crystal display (VA-LCD) panel were obtained noninvasively for the first time. With 1 µm axial and 2 µm transversal resolutions, the cell gap profile beneath the patterned thin-film transistor of the VA-LCD panel can clearly be resolved. The thicknesses of the multiple thin-film layers and the embedded defects can also be unveiled. As far as spectral response is concerned, the light transmittance at the layer boundaries can be estimated from the measured reflectance, which is crucial information for the design of a highly transmissive panel. The color shift of the VA-LCD panel due to fabrication error was evaluated.

Cell parameter measurement of a twisted nematic liquid crystal device using interferometric polarimeter under normal incidence.

Five cell parameters of a twisted nematic liquid crystal device (TNLCD), namely, cell gap, pretilt angle, twisted angle, rubbing angle, and phase retardation are precisely measured by the developed amplitude-sensitive heterodyne polarimeter (ASHP) simultaneously integrated with Yeh and Gu's transfer matrix and Lien's transfer matrix. This proposed method can characterize the five cell parameters under the arrangement of a single wavelength at normal incidence. In contrast to the conventional methods on cell parameter detection either by adopting a multiple wavelength laser beam at normal incidence or by using a single wavelength laser beam under oblique incident to TNLCD, this method presents the advantage of not only having a simple setup but also the possibility to measure simultaneously five cell parameters on the characterization of TNLCD at high speed.

Ce3+:YAG double-clad crystal-fiber-based optical coherence tomography on fish cornea.

A Ce(3+):YAG double-clad crystal fiber (DCF) visible emission was used as the light source for optical coherence tomography (OCT). The visible emission was produced from a 10 microm core DCF pumped by a diode laser. The broadband emission and short central wavelength of this light source enabled the realization of 1.5 microm axial resolution in air. The relatively clean spectrum reduced the side lobe of its point-spread function, and therefore facilitated the generation of a high-quality image with less crosstalk between adjacent image pixels. As a demonstration, an Aplocheilus lineatus goldfish was experimented on to map out the stroma of its cornea. This visible-light-based OCT can be utilized for industrial inspection as well as ocular applications.

MDCT in the early recognition of isolated non-penetrating pancreatic transection.

Isolated pancreatic transection is rare. Associated main pancreatic duct injury is the principal determinant factor of outcome. Earlier computed tomographic scanner may be unreliable in determining the location and severity of pancreatic injury. Multiplanar reconstruction (MPR) and curved views of multidetector computed tomography are helpful in accurate diagnosis of pancreatic transection with the main pancreatic duct injury.

Two-dimensional cell parameters of twisted nematic liquid crystal with an amplitude-sensitive heterodyne ellipsometer.

To be compared with the wavelength modulation technique for measuring two-dimensional (2D) cell parameters of a twisted nematic liquid crystal (TN-LC), we propose an amplitude-sensitive heterodyne ellipsometer (ASHE) of a single wavelength that is able to characterize TN-LC in 2D quantitatively. A quarter-wave plate (QWP) is rotated continuously in this setup to modulate the polarization state of the incident laser beam to obtain the amplitude ratio of the S and P waves versus the rotation angle of the QWP. Thus the cell parameters, including the twisted angle Phi, untwisted phase retardation Gamma, rubbing direction angle alpha, and cell gap d, of a TN-LC cell are obtained simultaneously by best fitting the detected amplitude ratio with a prediction based on the transfer matrix of TN-LC cell. 2D distributions of (Phi,Gamma,alpha,d) are then obtained either by scanning the TN-LC cell or by using a CCD camera for high-speed measurement. In this experiment, the stability of the amplitude-ratio measurement of the proposed ASHE was 0.5%. The goal is to integrate the rotating elliptical wave plate with the TN-LC cell in a heterodyne ellipsometer to obtain cell parameters at amplitude sensitivity. This increases not only the sensitivity of the measurement but also the possibility of extending the 2D distribution of cell parameters in real time.

Restenotic hepaticojejunostomy secondary to laparoscopic cholecistectomy bile duct injury treated with self- modified Gianturco-Rosh stents.

BACKGROUND/AIMS: Laparoscopic cholecystectomy is considered as a standard procedure for symptomatic gallstones. However, the incidence of iatrogenic bile duct injury is higher that the conventional cholecystectomy. In the present study was analyzed the results in 6 patients with iatrogenic bile duct injury during laparoscopic cholecystectomy with restenotic hepaticojejunostomy treated with self-modified Gianturco-Rosch stents. METHODOLOGY: Data were collected retrospectively on May 2000 to October 2008 on six patients with major bile duct injury secondary to cholecystectomy. All patients underwent surgical reconstruction with a Roux-en-Y hepaticojejunostomy and presented clinically as obstructive jaundice. Percutaneous transhepatic and/or endoscopic retrograde cholangiography, cholangioplasty by balloon dilation and biliary catheter placement were done in each patient prior to stents placement. Modified Gianturco-Rosch stents with 3cm length and 10mm diameter were used. Follow-up was obtained with direct patients contact or hospital records. RESULTS: Metallic stents were successfully implanted in all 6 patients and the mean patency rate was 46.5 months (range = 14-101 months). One patient required percutaneous recanalization procedure for recurrent cholangitis and obstruction. CONCLUSIONS: Gianturco-Rosch stents placement should be considered in patient with post-hepaticojejunostomy restenosis that repeat surgery is not feasible.

Differential phase decoder in a polarized optical heterodyne interferometer.

A differential-phase decoder (DPD) together with a polarization common-path optical heterodyne interferometer is set up. Based on this interferometric configuration and a novel balanced-detector scheme, the performance of the quantum-noise-limited differential-phase decoder is demonstrated and analyzed. The minimum-detectable differential phase is on the order of 10(-7) rad/sqrt Hz when a 2.5 mW He-Ne laser is used. Verified experimentally, the DPD is immune to the common-phase noise induced by an electro-optic phase modulator or by thermal disturbance within the interferometer. This signifies that the minimum-detectable differential phase can become 10(-8) rad/sqrt Hz if a 300 mW continuous wave laser is employed instead.

High speed interferometric ellipsometer.

A novel high speed interferometric ellipsometer (HSIE) is proposed and demonstrated. It is based on a novel differential-phase decoder which is able to convert the phase modulation into amplitude modulation in a polarized heterodyne interferometer. Not only high detection sensitivity but also fast response ability on ellipsometric parameters (EP) measurements based on amplitude-sensitive method is constructed whereas different amplitudes with respect to P and S polarized heterodyne signals in this phase to amplitude modulation conversion is discussed. The ability of HSIE was verified by testing a quarter wave plate while a real time differential-phase detection of a liquid crystal device versus applied voltage by using HSIE was demonstrated too. These results confirm that HSIE is able to characterize the optical property of specimen in terms of EP at high speed and high detection sensitivity experimentally.

Determination of retardation parameters of multiple-order wave plate using a phase-sensitive heterodyne ellipsometer.

To characterize the linear birefringence of a multiple-order wave plate (MWP), an oblique incidence is one of the methods available. Multiple reflections in the MWP are produced, and oscillations in the phase retardation measurement versus the oblique incident angle are then measured. Therefore, an antireflection coated MWP is required to avoid oscillation of the phase retardation measurement. In this study, we set up a phase-sensitive heterodyne ellipsometer to measure the phase retardations of an uncoated MWP versus the oblique incident angle, which was scanned in the x-z plane and y-z plane independently. Thus, the effect on multiple reflections by the MWP is reduced by means of subtracting the two measured phase retardations from each other. As a result, a highly sensitive and accurate measurement of retardation parameters (RPs), which includes the refractive indices of the extraordinary ray n(e) and ordinary ray n(o), is obtained by this method. On measurement, a sensitivity (n(e),n(o)) of 10(-6) was achieved by this experiment setup. At the same time, the spatial shifting of the P and S waves emerging from the MWP introduced a deviation between experimental results and the theoretical calculation.

Transcatheter arterial coil embolization of iatrogenic pseudoaneurysms after hepatobiliary and pancreatic interventions.

BACKGROUND/AIMS: Visceral and renal arteries pseudoaneurysms are uncommon but potentially lethal complications of hepatic and pancreatobiliary interventions. To evaluate the clinical outcome of transcatheter arterial coils embolotherapy, we reviewed our institution's experience with the management for bleeding pseudoaneurysms. METHODOLOGY: From January 1988 through December 2004, 20 patients were encountered who developed massive bleeding from pseudoaneurysms following hepatobiliary and pancreatic interventions. All patients underwent diagnostic angiography and transarterial embolization was carried out thereafter. RESULTS: Embolization was technically successful without major post-procedural complications in all patients. Bleeding was stopped after embolization in 17 patients (85%), and rebleeding did occur in one patient during the follow-up periods. Repeat coil embolotherapy was performed in one patient with recurrent bleeding, but they needed surgical intervention because of failed re-embolization. Another two patients needed surgical ligation and one of the patients died of sepsis two weeks later. CONCLUSIONS: An emergency angiography should be considered in all patients in whom pseudoaneurysm is suspected following hepatobiliary and pancreatic interventions. Transcatheter arterial coil embolization is a safe and effective treatment for pseudoaneurysm. Surgical intervention should be reserved for patients for whom embolization fails or for whom it is not possible.

Balanced detector interferometric ellipsometer.

A novel balanced detector interferometric ellipsometer (BDIE), composed of a polarized common-path optical heterodyne interferometer incorporating a novel balanced detector, provides an amplitude-sensitive method for measurement of the elliptical parameters of a thin film. The requirement for equal amplitude of the polarized heterodyne signals for balanced detection results in the simultaneous measurement of the elliptical parameters in terms of the azimuth angle of a half-wave plate and the output intensity from the differential amplifier, respectively. The common-path feature of BDIE shows a common phase noise rejection mode and this enhances the sensitivity of the phase measurement. At the same time, the balanced detector configuration of BDIE reduces excess noise of laser intensity fluctuation to give better sensitivity during measurement. The error of measurement of BDIE is derived and analyzed. Finally, the elliptical polarization effect of the laser beam is found to be independent of the measurement of the elliptical parameters.

Development of a new method for small bowel transit study.

BACKGROUND AND PURPOSE: Currently, most studies combine the small bowel transit examination with gastric emptying time examination. There are significant drawbacks to this method. The radiotracer does not enter the small intestine in a bolus and the starting time for transit in the duodenum is difficult to define. This makes the result unreliable. In this study, we used a commercial enteric capsule containing radioactive charcoal to solve these problems. MATERIALS AND METHODS: Activated charcoal powder was mixed with Tc-99m pertechnetate and loaded to the enteric capsule which can resist gastric acid and dissolve only in the small intestine. In-vitro stability experiment was performed by immersing these capsules in a colorless phosphate buffer of variable pH which mimicked the condition in stomach and small intestine. In addition, ten healthy Chinese volunteers were included for in-vivo experiment. Anterior and posterior views of abdomen were obtained at regular 30-minute intervals until the eighth hour after administration of the radioactive enteric capsule. Small bowel transit time was calculated. RESULTS: The enteric capsule remained intact for at least 480 minutes in the solution mimicking gastric content (pH = 3.0) and disrupted at a mean duration of 227.2 minutes at a pH of 6.8 and at a mean duration of 212.4 minutes at a pH of 7.4 in the solution mimicking pancreaticobiliary secretions. In nine of ten volunteers, the small bowel transit time was between 30 to 270 minutes with a mean transit time of 140 min. In one volunteer, we failed to detect the exact time of small bowel transit because the capsule remained in the stomach throughout the study for up to 8 hours. CONCLUSIONS: We consider activated charcoal labeled with Tc-99m pertechnetate using an enteric capsule as the carrier to be a potential radioactive marker for small bowel transit study.

Effectiveness of delayed 2-day lymphoscintigraphy on sentinel lymph node detection in patients with breast cancer with negative early lymphoscintigraphy.

PURPOSE: Most centers perform lymphoscintigraphy for the detection of sentinel lymph node (SLN) in patients with breast cancer within 2 hours after radiotracer injection. However, the interval between the injection of the radiotracer and surgery may not be long enough. In this study, we evaluated the effectiveness of delayed imaging (more than 15 hours) for SLN detection in patients with negative early images. METHODS: We retrospectively analyzed a database of 401 patients with breast cancer referred for SLN detection. On the day before surgery, lymphoscintigrams were obtained at 30-minute intervals until SLN was detected or 120 minutes. In those patients who failed to localize SLN on the early images, delayed imaging was performed the next morning. RESULTS: Twenty-seven (6.7%) patients failed to show SLN on the early images. In the 27 patients, delayed imaging was available for 14 patients but not for 13 patients resulting from the tight time schedule for surgery. Of the 14 patients with delayed images, SLNs were successfully harvested in 10 patients (71.4%) at surgery. In contrast, in the 13 patients who lacked delayed images, SLN was only harvested in one case (7.7%) at surgery. The intraoperative detection rate for SLN was significantly higher in the 14 patients with delayed images than that in the 13 patients without delayed images. CONCLUSIONS: Two-day delayed imaging is significantly useful to increase the rate of localizing SLN at surgery in patients with a negative early image.

Comparison of Tc-99m sestamibi and F-18 FDG-PET in the assessment of multiple myeloma.

BACKGROUND: Tc-99m methoxy-isobutyl-isonitrile (MIBI) has been reported to be a useful tracer in patients with multiple myeloma (MM). Few articles have reported the potential value of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) in the evaluation of MM. Therefore, the purpose of this study was to compare the diagnostic abilities of the MIBI scan and the FDG-PET scan in the evaluation of MM. MATERIALS AND METHODS: Twelve patients with MM were included. All patients received a radiological skeletal survey, MIBI scan and FDG-PET scan. RESULTS: Thirty-four lesions (19 soft tissue lesions and 15 skeletal lesions) plus 5 cases of bone marrow involvement were detected. The conventional skeletal X-ray survey detected 4 soft tissue lesions (21.1%), 12 skeletal lesions (80%), but no bone marrow involvement (0%). The MIBI scan found 4 cases of bone marrow involvement (80%), 13 soft tissue lesions (68.4%) and 12 skeletal lesions (80%). The PET scan detected 5 cases of bone marrow involvement (100%), 17 soft tissue lesions (89.5%) and 14 skeletal lesions (93.3%). CONCLUSION: Both the MIBI and the FDG-PET scans are useful in the evaluation of patients with MM. However, FDG-PET can detect more lesions than the MIBI scan in patients with MM.