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Robotic surgery bedside assistants play an important role in robotic procedures by performing intra-corporeal tasks while accommodating the physical presence of the robot. We hypothesized that an augmented reality headset enabling 3D intra-corporeal vision while facing the surgical field could decrease time and improve accuracy of robotic bedside tasks. Bedside assistants (one physician assistant, one medical student, three surgical trainees, and two attending surgeons) performed validated tasks within a mock abdominal cavity with a surgical robot docked. Tasks were performed with a bedside monitor providing 2D or 3D vision, or an optical see-through head-mounted augmented reality device with 2D or 3D vision. The effect of augmented reality device resolution on performance was also evaluated. For the simplest task of touching a straw, performance was generally high, regardless of mode of visualization. With more complex tasks, including stapling and pulling a ring along a path, 3D augmented reality decreased time and number of errors per task. 3D augmented reality allowed the physician assistant to perform at the level of an attending surgeon using 3D augmented reality (p = 0.08). All participants had improved times for the ring path task with better resolution (lower resolution 23 ± 11 s vs higher resolution 14 ± 4 s, p = 0.002). 3D augmented reality vision with high resolution decreased time and improved accuracy of more complex tasks, enabling a less experienced robotic surgical bedside assistant to function similar to attending surgeons. These data warrant further study with additional complex tasks and bedside assistants at various levels of training.

Surgical resection of tumours requires precisely locating and defining the margins between lesions and normal tissue. However, this is made difficult by irregular margin borders. Although molecularly targeted optical contrast agents can be used to define tumour margins during surgery in real time, the selectivity of the contrast agents is often limited by the target being expressed in both healthy and tumour tissues. Here, we show that AND-gate optical imaging probes that require the processing of two substrates by multiple tumour-specific enzymes produce a fluorescent signal with significantly improved specificity and sensitivity to tumour tissue. We evaluated the performance of the probes in mouse models of mammary tumours and of metastatic lung cancer, as well as during fluorescence-guided robotic surgery. Imaging probes that rely on multivariate activation to selectively target complex patterns of enzymatic activity should be useful in disease detection, treatment and monitoring.

Author(s): Lee, Yu-Jin; van den Berg, Nynke S; Orosco, Ryan K; Rosenthal, Eben L; Sorger, Jonathan M | Abstract: ObjectiveIn this review, we provide examples of applications of fluorescence imaging in urologic, gynecologic, general, and endocrine surgeries.BackgroundWhile robotic-assisted surgery has helped increase the availability of minimally invasive procedures across surgical specialties, there remains an opportunity to reduce adverse events associated with open, laparoscopic, and robotic-assisted methods. In 2011, fluorescence imaging was introduced as an option to the da Vinci Surgical System, and has been standard equipment since 2014. Without interfering with surgical workflow, this fluorescence technology named Firefly® allows for acquisition and display of near-infrared fluorescent signals that are co-registered with white light endoscopic images. As a result, robotic surgeons of all specialties have been able to explore the clinical utility of fluorescence guided surgery.MethodsLiterature searches were performed using the PubMed and MEDLINE databases using the keywords "robotic-assisted fluorescence surgery", "ICG robotic surgery", and "fluorescence guided surgery" covering the years 2011-2020.ConclusionsReal-time intraoperative fluorescence guidance has shown great potential in helping guide surgeons in both simple and complex surgical interventions. Indocyanine green is one of the most widely-used imaging agents in fluorescence guided surgery, and other targeted, near-infrared imaging agents are in various stages of development. Fluorescence is becoming a reliable tool that can help surgeons in their decision-making process in some specialties, while explorations continue in others.

Fluorescence-guided surgery (FGS) to aid in the precise visualization of vital nerve structures in real-time intraoperatively could greatly improve patient outcomes. We took a medicinal chemistry approach that facilitated the design of our first-in-class NIR nerve-binding small molecule fluorophore libraries with excitation and emission profiles compatible with the “700-” and “800-” nm fluorescence imaging channels in the clinical grade FGS systems. Molecular engineering of the lead candidates allowed for the development of water-soluble nerve-specific contrast agents with improved safety profile that has great potential for clinical translation in the near future.

Nerve damage plagues surgical outcomes, significantly affecting post-surgical quality of life. Intraoperative nerve detection is difficult since neuroanatomy is varilable between patients, and nerves are typically protected deep within the tissue. Fluorescence-guided surgery (FGS) offers a potential means for enhanced intraoperative nerve identification and preservation. We have developed the first near infrared (NIR) nerve-specific fluorophores for use during FGS. Lead optimization has yielded water soluble derivatives with excellent safety and pharmacology parameters. Work is underway to plan and execute preclinical toxicity testing to enable first-in-human clincial trials.

The da Vinci Surgical System is a platform for robot-assisted minimally invasive surgery. This chapter provides an overview of the design of the da Vinci System, as well as several of its key subsystems for vision, tissue manipulation, anatomical access, and operator technology training. Clinical adoption of the system to-date is described briefly, and we leave the reader with some thoughts on possible future development directions.

Tumor removal typically involves electrocautery, but no studies to date have quantified the effect of electrocautery on fluorescence emission. Electrocautery was applied to N=4 locations of the oral cavity and striated leg muscle of a live Yorkshire pig. Autofluorescence of cauterized tissues and surrounding regions was measured at distinct time points up to 120 minutes following cauterization. The fluorescence lifetime was spectrally resolved in four spectral detection channels that maximized the signal emanating from endogenous fluorophores of interest. The autofluorescence emission (355 nm excitation) was temporally resolved using a high-speed digitizer; resulting fluorescence decay characteristics were retrieved using the Laguerre deconvolution technique. Histology was performed and co-registered with the autofluorescence data. Results show that cauterized tissue presents a distinct autofluorescence signature from surrounding regions immediately after cauterization. Differences become less evident with time. The autofluorescence-derived parameters suggest altered metabolism in peripheral regions compared to the region of maximal damage. Within the time-frame of this study, tissues investigated show variable degrees of recovery from the effects of electrocautery that can be monitored by changes in fluorescence lifetime characteristics. Our findings suggest delineation of pathologic conditions could be affected by tissue cauterization and that future studies in this area will be necessary.

Molecularly targeted optical contrast agents have the potential to enable surgeons to visualize specific molecular markers that can help improve surgical precision and thus outcomes. Fluorescently quenched substrates can be used to highlight tumor lesions by targeting proteases that are highly abundant in the tumor microenvironment. However, the majority of these and other molecularly targeted optical contrast agents are labeled with reporter dyes that are not ideally matched to the properties of clinical camera systems, which are typically optimized for detection of indocyanine-green (ICG). While a wide range of near-infrared (NIR) dyes are suitable for use with highly sensitive and highly tunable research-focused small animal imaging systems, most have not been evaluated for use with commonly used clinical imaging systems. Here we report the optimization of a small molecule fluorescently quenched protease substrate probe 6QC-ICG, which uses the indocyanine green (ICG) dye as its optical reporter. We evaluated dosing and kinetic parameters of this molecule in tumor-bearing mice and observed optimal tumor over background signals in as little as 90 min with a dose of 2.3 mg/kg. Importantly, the fluorescence intensity of the probe signal in tumors did not linearly scale with dose, suggesting the importance of detailed dosing studies. Furthermore, when imaged using the FDA approved da Vinci Si surgical system with Firefly detection, signals were significantly higher for the ICG probe compared to a corresponding probe containing a dye with similar quantum yield but with a slightly shifted excitation and emission profile. The increased signal intensity generated by the optimal dye and dose of the ICG labeled probe enabled detection of small, flat lesions that were less than 5 mm in diameter. Therefore, 6QC-ICG is a highly sensitive probe that performs optimally with clinical imaging systems and has great potential for applications in optical surgical navigation.

With the advent of precision surgery, there have been attempts to integrate imaging with robotic systems to guide sound oncologic surgical resections while preserving critical structures. In the confined space of transoral robotic surgery (TORS), this offers great potential given the proximity of structures. In this cadaveric experiment, we describe the use of a 3D virtual model displayed in the surgeon's console with the surgical field in view, to facilitate image-guided surgery at the oropharynx where there is significant soft tissue deformation. We also utilized the 3D model that was registered to the maxillary dentition, allowing for real-time image overlay of the internal carotid artery system. This allowed for real-time visualization of the internal carotid artery system that was qualitatively accurate on cadaveric dissection. Overall, this shows that virtual models and image overlays can be useful in image-guided surgery while approaching different sites in head and neck surgery with TORS.

The fluorescent imaging agent IS-001 was determined to be well tolerated in all subjects and has the potential to provide ureter visualization throughout minimally invasive hysterectomy procedures. This study was conducted to evaluate clinical safety and efficacy of a real-time ureter visualization technique for use during hysterectomy surgery. The study drug appears safe, is renally excreted, and allows enhanced ureter visualization when imaged with a clinically approved near-infrared sensitive endoscope. This is a first-in-human study showing preliminary results that the drug is safe and effective during surgery for improved ureter visualization.

Nerve-binding fluorophores with near-infrared (NIR; 650 to 900 nm) emission could reduce iatrogenic nerve injury rates by providing surgeons precise, real-time visualization of the peripheral nervous system. Unfortunately, current systemically administered nerve contrast agents predominantly emit at visible wavelengths and show nonspecific uptake in surrounding tissues such as adipose, muscle, and facia, thus limiting detection to surgically exposed surface-level nerves. Here, a focused NIR fluorophore library was synthesized and screened through multi-tiered optical and pharmacological assays to identify nerve-binding fluorophore candidates for clinical translation. NIR nerve probes enabled micrometer-scale nerve visualization at the greatest reported tissue depths (~2 to 3 mm), a feat unachievable with previous visibly emissive contrast agents. Laparoscopic fluorescent surgical navigation delineated deep lumbar and iliac nerves in swine, most of which were invisible in conventional white-light endoscopy. Critically, NIR oxazines generated contrast against all key surgical tissue classes (muscle, adipose, vasculature, and fascia) with nerve signal-to-background ratios ranging from ~2 (2- to 3-mm depth) to 25 (exposed nerve). Clinical translation of NIR nerve-specific agents will substantially reduce comorbidities associated with surgical nerve damage.

Due to loss of tactile feedback the assessment of tumor margins during robotic surgery is based only on visual inspection, which is neither significantly sensitive nor specific. Here we demonstrate time-resolved fluorescence spectroscopy (TRFS) as a novel technique to complement the visual inspection of oral cancers during transoral robotic surgery (TORS) in real-time and without the need for exogenous contrast agents. TRFS enables identification of cancerous tissue by its distinct autofluorescence signature that is associated with the alteration of tissue structure and biochemical profile. A prototype TRFS instrument was integrated synergistically with the da Vinci Surgical robot and the combined system was validated in swine and human patients. Label-free and real-time assessment and visualization of tissue biochemical features during robotic surgery procedure, as demonstrated here, not only has the potential to improve the intraoperative decision making during TORS but also other robotic procedures without modification of conventional clinical protocols.

Nerves are extremely difficult to identify and are often accidently damaged during surgery, leaving patients with lasting pain and numbness. Herein, a novel near-infrared (NIR) nerve-specific fluorophore, LGW01–08, was utilized for enhanced nerve identification using fluorescence guided surgery (FGS), formulated using clinical translatable strategies. Formulated LGW01–08 was examined for toxicology, pharmacokinetics (PK), and pharmacodynamics (PD) parameters in preparation for future clinical translation. Optimal LGW01–08 imaging doses were identified in each formulation resulting in a 10x difference between the toxicity to imaging dose window. Laparoscopic swine surgery completed using the da Vinci surgical robot (Intuitive Surgical) demonstrated the efficacy of formulated LGW01–08 for enhanced nerve identification. NIR fluorescence imaging enabled clear identification of nerves buried beneath ~3 mm of tissue that were unidentifiable by white light imaging. These studies provide a strong basis for future clinical translation of NIR nerve-specific fluorophores for utility during FGS to improve patient outcomes.

Visualization can be defined as “a technique for creating images, diagrams, or animations to communicate a message” [1]. Visualization in surgical robotics involves displaying images of patient anatomy to the surgeon. Such images can be provided by optical or tomographic imaging techniques.

Inability to integrate surgical navigation systems into current surgical robot is one of the reasons for the lack of development of robotic endoscopic skull base surgery. We describe an experiment to adapt current technologies for real-time navigation during transoral robotic nasopharyngectomy. A cone-beam CT was performed with a robotic C-arm after the injecting contrast into common carotid artery. 3D reconstruction of the skull images with the internal carotid artery (ICA) highlighted red was projected on the console. Robotic nasopharyngectomy was then performed. Fluoroscopy was performed with the C-arm. Fluoroscopic image was then overlaid on the reconstructed skull image. The relationship of the robotic instruments with the bony landmarks and ICA could then been viewed in real-time, acting as a surgical navigation system. Navigation during robotic skull base surgery is feasible with available technologies and can increase the safety of robotic skull base surgery.

In transoral robotic surgery preoperative image data do not reflect large deformations of the operative workspace from perioperative setup. To address this challenge, in this study we explore image guidance with cone beam computed tomographic angiography to guide the dissection of critical vascular landmarks and resection of base-of-tongue neoplasms with adequate margins for transoral robotic surgery. We identify critical vascular landmarks from perioperative c-arm imaging to augment the stereoscopic view of a da Vinci si robot in addition to incorporating visual feedback from relative tool positions. Experiments resecting base-of-tongue mock tumors were conducted on a series of ex vivo and in vivo animal models comparing the proposed workflow for video augmentation to standard non-augmented practice and alternative, fluoroscopy-based image guidance. Accurate identification of registered augmented critical anatomy during controlled arterial dissection and en bloc mock tumor resection was possible with the augmented reality system. The proposed image-guided robotic system also achieved improved resection ratios of mock tumor margins (1.00) when compared to control scenarios (0.0) and alternative methods of image guidance (0.58). The experimental results show the feasibility of the proposed workflow and advantages of cone beam computed tomography image guidance through video augmentation of the primary stereo endoscopy as compared to control and alternative navigation methods.

There is a need for new molecular-guided contrast agents to enhance surgical procedures such as tumor resection that require a high degree of precision. Cysteine cathepsins are highly up-regulated in a wide variety of cancers, both in tumor cells and in the tumor-supporting cells of the surrounding stroma. Therefore, tools that can be used to dynamically monitor their activity in vivo could be used as imaging contrast agents for intraoperative fluorescence image guided surgery (FGS). Although multiple classes of cathepsin-targeted substrate probes have been reported, most suffer from overall fast clearance from sites of protease activation, leading to reduced signal intensity and duration in vivo. Here we describe the design and synthesis of a series of near-infrared fluorogenic probes that exploit a latent cationic lysosomotropic effect (LLE) to promote cellular retention upon protease activation. These probes show tumor-specific retention, fast activation kinetics, and rapid systemic distribution. We demonstrate that they are suitable for detection of diverse cancer types including breast, colon and lung tumors. Most importantly, the agents are compatible with the existing, FDA approved, da Vinci surgical system for fluorescence guided tumor resection. Therefore, our data suggest that the probes reported here can be used with existing clinical instrumentation to detect tumors and potentially other types of inflammatory lesions to guide surgical decision making in real time.

C-arm radiographs are commonly used for intraoperative image guidance in surgical interventions. Fluoroscopy is a cost-effective real-time modality, although image quality can vary greatly depending on the target anatomy. Cone-beam computed tomography (CBCT) scans are sometimes available, so 2D–3D registration is needed for intra-procedural guidance. C-arm radiographs were registered to CBCT scans and used for 3D localization of peritumor fiducials during a minimally invasive thoracic intervention with a da Vinci Si robot. Intensity-based 2D–3D registration of intraoperative radiographs to CBCT was performed. The feasible range of X-ray projections achievable by a C-arm positioned around a da Vinci Si surgical robot, configured for robotic wedge resection, was determined using phantom models. Experiments were conducted on synthetic phantoms and animals imaged with an OEC 9600 and a Siemens Artis zeego, representing the spectrum of different C-arm systems currently available for clinical use. The image guidance workflow was feasible using either an optically tracked OEC 9600 or a Siemens Artis zeego C-arm, resulting in an angular difference of $$\Delta \theta : \sim 30^{\circ }$$ . The two C-arm systems provided $$\hbox {TRE}_\mathrm{mean} \le 2.5 \hbox { mm}$$ and $$\hbox {TRE}_\mathrm{mean} \le 2.0 \hbox { mm}$$ , respectively (i.e., comparable to standard clinical intraoperative navigation systems). C-arm 3D localization from dual 2D–3D registered radiographs was feasible and applicable for intraoperative image guidance during da Vinci robotic thoracic interventions using the proposed workflow. Tissue deformation and in vivo experiments are required before clinical evaluation of this system.

Multi-Spectral Time-Resolved Fluorescence Spectroscopy (ms-TRFS) can provide label-free real-time feedback on tissue composition and pathology during surgical procedures by resolving the fluorescence decay dynamics of the tissue. Recently, an ms-TRFS system has been developed in our group, allowing for either point-spectroscopy fluorescence lifetime measurements or dynamic raster tissue scanning by merging a 450 nm aiming beam with the pulsed fluorescence excitation light in a single fiber collection. In order to facilitate an augmented real-time display of fluorescence decay parameters, the lifetime values are back projected to the white light video. The goal of this study is to develop a 3D real-time surface reconstruction aiming for a comprehensive visualization of the decay parameters and providing an enhanced navigation for the surgeon. Using a stereo camera setup, we use a combination of image feature matching and aiming beam stereo segmentation to establish a 3D surface model of the decay parameters. After camera calibration, texture-related features are extracted for both camera images and matched providing a rough estimation of the surface. During the raster scanning, the rough estimation is successively refined in real-time by tracking the aiming beam positions using an advanced segmentation algorithm. The method is evaluated for excised breast tissue specimens showing a high precision and running in real-time with approximately 20 frames per second. The proposed method shows promising potential for intraoperative navigation, i.e. tumor margin assessment. Furthermore, it provides the basis for registering the fluorescence lifetime maps to the tissue surface adapting it to possible tissue deformations.

Background Adequate resection of oropharyngeal neoplasms with transoral robotic surgery (TORS) poses multiple challenges, including difficulty with access, inability to palpate the tumor, loss of landmarks, and intraoperative patient positioning with mouth retractor and tongue extended creating significant tissue distortion from preoperative imaging. Methods This study evaluates a workflow integrating intraoperative cone beam computed tomography (CBCT) for image-guided TORS through robotic experimentation locating 8–10 embedded targets in five porcine tongues and a cadaveric head phantom, conducted under various modes of visualization and integration of preoperative/intraoperative imaging. Results A statistically significant improvement in mean target localization error was achieved for both the porcine tongue ((9.8±4.0) mm vs. (5.3±1.3) mm, P-value=0.0151) and cadaver ((11.2±5.0) mm vs. (5.8±2.5) mm Pvalue=0.0189) in experiments comparing scenarios simulating current standard-of-care practice and the proposed image guidance system. Conclusion Intraoperative image guidance with augmentation of critical surgical structures has the potential to improve target localization for TORS. Copyright © 2014 John Wiley & Sons, Ltd.

This practice guideline on gestational diabetes is a treatment oriented short version of the evidence based guideline that can be viewed in the internet. It replaces the DDG and DGGG recommendations of 2001 for diagnostic and therapy of gestational diabetes. A complete rework had become necessary in view of epidemiologically based diagnostic criteria, which had been derived from the Hyperglycaemia and Adverse Pregnancy Outcome study (HAPO) by international consensus, and in view of randomised therapy and observation studies published after 2001. With this, Germany has adopted the international standard. Screening and diagnosing gestational diabetes by means of blood glucose are part of the legally binding maternity guidelines in Germany since March 3, 2012.

Transoral robotic surgery (TORS) offers a minimally invasive approach to resection of base-of-tongue tumors. However, precise localization of the surgical target and adjacent critical structures can be challenged by the highly deformed intraoperative setup. We propose a deformable registration method using intraoperative cone-beam computed tomography (CBCT) to accurately align preoperative CT or MR images with the intraoperative scene. The registration method combines a Gaussian mixture (GM) model followed by a variation of the Demons algorithm. First, following segmentation of the volume of interest (i.e. volume of the tongue extending to the hyoid), a GM model is applied to surface point clouds for rigid initialization (GM rigid) followed by nonrigid deformation (GM nonrigid). Second, the registration is refined using the Demons algorithm applied to distance map transforms of the (GM-registered) preoperative image and intraoperative CBCT. Performance was evaluated in repeat cadaver studies (25 image pairs) in terms of target registration error (TRE), entropy correlation coefficient (ECC) and normalized pointwise mutual information (NPMI). Retraction of the tongue in the TORS operative setup induced gross deformation >30 mm. The mean TRE following the GM rigid, GM nonrigid and Demons steps was 4.6, 2.1 and 1.7 mm, respectively. The respective ECC was 0.57, 0.70 and 0.73, and NPMI was 0.46, 0.57 and 0.60. Registration accuracy was best across the superior aspect of the tongue and in proximity to the hyoid (by virtue of GM registration of surface points on these structures). The Demons step refined registration primarily in deeper portions of the tongue further from the surface and hyoid bone. Since the method does not use image intensities directly, it is suitable to multi-modality registration of preoperative CT or MR with intraoperative CBCT. Extending the 3D image registration to the fusion of image and planning data in stereo-endoscopic video is anticipated to support safer, high-precision base-of-tongue robotic surgery.

Background The supraorbital keyhole approach has been used in anterior skull base tumor and aneurysm surgery. However, there are debates regarding the safety and limitations of this kind of approach. Objective To determine the feasibility and potential benefits of surgical robotic technology in minimally invasive neurosurgery. Methods Two fresh cadaver heads were studied with the da Vinci Surgical System with 0° and 30° stereoscopic endoscopes to visualize neuroanatomy. The ability of the system to suture and place clips under the keyhole approach was tested. Results The da Vinci Surgical System was used throughout the supraorbital transeyebrow keyhole approach. With the use of standard microdissection techniques, the optic nerve, optic chiasm, carotid artery, and third cranial nerve were visualized. The sylvian fissure was then exposed from the proximal sylvian membrane to the distal M1 segment. With the EndoWrist microforceps, suturing can be achieved smoothly to close a defect created on the M2 artery. Although the benefits in adjusting clips during aneurysm surgery could be provided by an articulating applier, a proper robotic applier is not currently available. Conclusion The minimally invasive supraorbital keyhole surgery can be achieved with the da Vinci Surgical System in cadaver models. This system provides neurosurgeons with broader vision and articulable instruments, which standard microsurgical systems do not provide. Further studies are necessary to evaluate the safety and benefits of using the da Vinci Surgical System in minimally invasive neurosurgery.

Prostatic neuroanatomy is difficult to visualize intraoperatively and can be extremely variable. Damage to these nerves during prostatectomies may lead to postoperative complications such as erectile dysfunction and incontinence. This review aims to discuss the prostatic neuroanatomy, sites of potential nerve damage during a prostatectomy, and nerve-mapping technologies being developed to prevent neural injury. These technologies include stimulation, dyes, and direct visualization. Nerve stimulation works by testing an area and observing a physiologic response but is limited by the long half-life for an erectile response; examples include CaverMap, ProPep, and optical nerve stimulation. Few nerve dyes have been approved by the Food and Drug Administration (FDA) because of the extensive testing required; examples of nerve dyes include compounds from Avelas and General Electric, fluorescent cholera toxin subunit B, indocyanine green, fluorescent inactivated herpes simplex 2, and Fluoro-Gold. Direct visualization techniques have a simpler FDA approval process; examples include optical coherence tomography, multiphoton microscopy, ultrasound, coherent anti-Stokes Raman scattering. Many researchers are developing several novel technologies that can be categorized as stimulation based, dye-based, or direct visualization. As of yet, none has shown clear evidence to improve surgical outcomes and consequently lack wide adoption. Further development of these technologies may lead to improved complication rates after prostatectomies. Clinically, some technologies have demonstrated utility in predicting the development of complications. By using that information, more aggressive rehabilitation programs may lead to improved long-term function. These technologies can also be applied for research to improve our knowledge of the neuroanatomy and physiology of erection and incontinence.

Die Deutsche Gesellschaft fur Gynakologie und Geburtshilfe und die Deutsche Diabetesgesellschaft haben im August 2011 eine evidenzbasierte Leitlinie zum Gestationsdiabetes verabschiedet. Die Uberarbeitung war notwendig, weil neue Daten aus randomisierten Therapiestudien und zur Diagnostik des GDM berucksichtigt werden mussten.

OBJECTIVE Up to 30% of women with recent gestational diabetes mellitus (GDM) remain glucose intolerant after delivery. However, the rate of postpartum oral glucose tolerance tests (ppOGTTs) is low. Our aim in this study was to develop a model for risk assessment to target women with high risk for postpartum diabetes. RESEARCH DESIGN AND METHODS In 605 Caucasian women with GDM, antenatal obstetrical and glucose data and the glucose data of the ppOGTTs performed 13 weeks (median) after delivery were prospectively collected. RESULTS A total of 132 (21.8%) women had an abnormal ppOGTT (2.8% impaired fasting glucose, 13.6% impaired glucose tolerance, and 5.5% diabetes). Independent risk factors were BMI ≥30 kg/m2 (prevalence of abnormal ppOGTT 36.0 vs. 17.3%), gestational age at diagnosis 200 mg/dl (11.1 mmol/l) (35.2 vs. 14.8%), and insulin therapy (30.3 vs. 14.5%). The prevalence of an abnormal ppOGTT was assessed according to the number of risk factors: 0, 9.2% (14 of 153); 1, 13.4% (25 of 186); 2, 28.5% (43 of 151); 3, 45.6% (26 of 57); and 4, 68.4% (13 of 19). Subjects were divided according to a significant increase of prevalence and risk for a ppOGTT: low risk (59.9% of subjects), 2 risk factors, 51.3%, 10.5. The intermediate/high-risk group included 86.6% of those with diabetes and 67% of all those with abnormal ppOGTTs. CONCLUSIONS Women with ≥2 risk factors have a high risk for an abnormal ppOGTT, and 86% of postpartum diabetes is diagnosed within this group. Targeting women for ppOGTTs based on a risk assessment using available antenatal risk factors might reduce the number of missed cases of postpartum diabetes.

Schwangerschaften bei Frauen mit manifestem Diabetes mellitus stellen ein hohes Risiko fur Mutter und Kind dar. Vor Einfuhrung des Insulins war die Schwangerschaft bei Diabetikerinnen ein sehr seltenes Ereignis. Mit der Verfugbarkeit des Insulins konnten dann auch Frauen mit einem insulinpflichtigen Diabetes eine Schwangerschaft erwagen, wobei die mutterliche Sterblichkeit weiterhin bei ca. 10% und die kindliche bei 45–50% lag. Wahrend in den 1960er Jahren die perinatale Mortalitat noch immer ca. 20% betrug, konnten Mortalitat und Morbiditat bei Mutter und Kind in den vergangenen Jahrzehnten durch die verbesserten therapeutischen Moglichkeiten und eine enge interdisziplinare Betreuung durch spezialisierte Teams drastisch gesenkt werden. Im Vergleich zu nichtdiabetischen Schwangerschaften besteht aber immer noch ein 3- bis 5fach hoheres kongenitales Fehlbildungsrisiko. Auch die perinatale Mortalitat liegt uber der von Kindern stoffwechselgesunder Mutter.

For ten years, severe physical exercise in a 24 year old male patient had been an almost constant trigger of frequent attacks of pareses which were mostly accompanied by complete tetraplegia and once by the occurrence of cardiac arrest with atrial fibrillation. During the attack, the serum potassium concentration fell to 1.2 mmol/l, whereas the intraleukocytic potassium concentration rose from 136 mmol/l to 149 mmol/l. The catecholamine excretion in the urine was raised during the first 24 hours after admission as an emergency (189 micrograms noradrenalin and 54 micrograms adrenalin). After intravenous adrenalin infusion (0.01-0.1 microgram/kg X min) during the symptom-free interval, there was a major fall of the serum potassium concentration from 3.9 mmol/l to 3.1 mmol/l. This was not accompanied by a raised insulin excretion and could be prevented by prior administration of the nonselective beta blocker propranolol. On the basis of these results, the patient was treated prophylactically with three times 40 mg/d p.o. propranolol. Pareses requiring treatment no longer occurred under this therapy.

My wife is a history teacher. George Santayana’s observation that “those who cannot remember the past are condemned to repeat it,” rings true in the field of optical imaging in the operating room. Much can be learned from historic difficulties in bringing optical imaging modalities successfully into the clinical workflow of the surgical suite. Few of the critical milestones in this field will be realized unless creativity is used to demonstrate that the failure to successfully translate optical and other imaging modalities can be avoided in this nascent area.

This paper presents the development and evaluation of video augmentation on the stereoscopic da Vinci S system with intraoperative image guidance for base of tongue tumor resection in transoral robotic surgery (TORS). Proposed workflow for image-guided TORS begins by identifying and segmenting critical oropharyngeal structures (e.g., the tumor and adjacent arteries and nerves) from preoperative computed tomography (CT) and/or magnetic resonance (MR) imaging. These preoperative planned data can be deformably registered to the intraoperative endoscopic view using mobile C-arm cone-beam computed tomography (CBCT) [1, 2]. Augmentation of TORS endoscopic video defining surgical targets and critical structures has the potential to improve navigation, spatial orientation, and confidence in tumor resection. Experiments in animal specimens achieved statistically significant improvement in target localization error when comparing the proposed image guidance system to simulated current practice.

Adequate resection of oropharyngeal neoplasms with transoral robotic surgery (TORS) poses multiple challenges, including difficulty with access, inability to palpate the tumor, loss of landmarks, and intraoperative patient positioning with mouth retractor and tongue extended creating significant tissue distortion from preoperative imaging.This study evaluates a workflow integrating intraoperative cone beam computed tomography (CBCT) for image-guided TORS through robotic experimentation locating 8-10 embedded targets in five porcine tongues and a cadaveric head phantom, conducted under various modes of visualization and integration of preoperative/intraoperative imaging.A statistically significant improvement in mean target localization error was achieved for both the porcine tongue ((9.8 ± 4.0) mm vs. (5.3 ± 1.3) mm, P-value = 0.0151) and cadaver ((11.2 ± 5.0) mm vs. (5.8 ± 2.5) mm P-value = 0.0189) in experiments comparing scenarios simulating current standard-of-care practice and the proposed image guidance system.Intraoperative image guidance with augmentation of critical surgical structures has the potential to improve target localization for TORS.

We have developed an intraoperative image guidance system that integrates information from cone beam computed tomography with video augmentation for transoral robotic surgery. A proposed workflow to overlay critical structures with relative tool positions on stereoscopic endoscopy for resection of base of tongue neoplasms was evaluated using ex vivo and in vivo animal models. Results included visual confirmations of augmented critical anatomy during controlled arterial dissection and successful mock tumor resection. The proposed image-guided robotic system also achieved improved resection ratios of mock tumor margins (1.00) when compared to control scenarios (0.0) and alternative methods of image guidance (0.58).

One of the main challenges for computer-assisted surgery (CAS) is to determine the intra-opera- tive morphology and motion of soft-tissues. This information is prerequisite to the registration of multi-modal patient-specific data for enhancing the surgeon’s navigation capabilites by observ- ing beyond exposed tissue surfaces and for providing intelligent control of robotic-assisted in- struments. In minimally invasive surgery (MIS), optical techniques are an increasingly attractive approach for in vivo 3D reconstruction of the soft-tissue surface geometry. This paper reviews the state-of-the-art methods for optical intra-operative 3D reconstruction in laparoscopic surgery and discusses the technical challenges and future perspectives towards clinical translation. With the recent paradigm shift of surgical practice towards MIS and new developments in 3D opti- cal imaging, this is a timely discussion about technologies that could facilitate complex CAS procedures in dynamic and deformable anatomical regions.

Four portable analyzers, HemoCue B-Glucose (I), Accu-Check III (II), One-touch II (III), and Glucometer Elite (IV), with different measuring principles were tested for their suitability for measuring blood glucose in neonates. Precision of all instruments is satisfactory. In the analysis of capillary blood from newborns, two instruments show an excellent accuracy; however, the scatter of the results for instrument (II) is about 1.6 times greater than for instrument (I). The inaccuracy of instruments (III) and (IV) is not acceptable from a clinical point of view. All devices show an influence of hematocrit, the magnitude of which varies between 5% (I) and 12% (III) for every 10% change of hematocrit. Instruments II and IV show that temperature has a marked influence on the readings; the same is true for oxygen in instrument IV. In conclusion, only instrument (I) has met the requirements of accurate and precise blood glucose determinations in neonates.

Purpose: An increasingly popular minimally invasive approach to resection of oropharyngeal / base-of-tongue cancer is made possible by a transoral technique conducted with the assistance of a surgical robot. However, the highly deformed surgical setup (neck flexed, mouth open, and tongue retracted) compared to the typical patient orientation in preoperative images poses a challenge to guidance and localization of the tumor target and adjacent critical anatomy. Intraoperative cone-beam CT (CBCT) can account for such deformation, but due to the low contrast of soft-tissue in CBCT images, direct localization of the target and critical tissues in CBCT images can be difficult. Such structures may be more readily delineated in preoperative CT or MR images, so a method to deformably register such information to intraoperative CBCT could offer significant value. This paper details the initial implementation of a deformable registration framework to align preoperative images with the deformed intraoperative scene and gives preliminary evaluation of the geometric accuracy of registration in CBCT-guided TORS. Method: The deformable registration aligns preoperative CT or MR to intraoperative CBCT by integrating two established approaches. The volume of interest is first segmented (specifically, the region of the tongue from the tip to the hyoid), and a Gaussian mixture (GM) mode1 of surface point clouds is used for rigid initialization (GMRigid) as well as an initial deformation (GMNonRigid). Next, refinement of the registration is performed using the Demons algorithm applied to distance transformations of the GM-registered and CBCT volumes. The registration accuracy of the framework was quantified in preliminary studies using a cadaver emulating preoperative and intraoperative setups. Geometric accuracy of registration was quantified in terms of target registration error (TRE) and surface distance error. Result: With each step of the registration process, the framework demonstrated improved registration, achieving mean TRE of 3.0 mm following the GM rigid, 1.9 mm following GM nonrigid, and 1.5 mm at the output of the registration process. Analysis of surface distance demonstrated a corresponding improvement of 2.2, 0.4, and 0.3 mm, respectively. The evaluation of registration error revealed the accurate alignment in the region of interest for base-of-tongue robotic surgery owing to point-set selection in the GM steps and refinement in the deep aspect of the tongue in the Demons step. Conclusions: A promising framework has been developed for CBCT-guided TORS in which intraoperative CBCT provides a basis for registration of preoperative images to the highly deformed intraoperative setup. The registration framework is invariant to imaging modality (accommodating preoperative CT or MR) and is robust against CBCT intensity variations and artifact, provided corresponding segmentation of the volume of interest. The approach could facilitate overlay of preoperative planning data directly in stereo-endoscopic video in support of CBCT-guided TORS.

Background — We tested the feasibility of targeted left ventricular (LV) mural injection using real-time MRI (rtMRI). Methods and Results — A 1.5T MRI scanner was customized with a fast reconstruction engine, transfemoral guiding catheter–receiver coil (GCC), MRI-compatible needle, and tableside consoles. Commercial real-time imaging software was customized to facilitate catheter navigation and visualization of injections at 4 completely refreshed frames per second. The aorta was traversed and the left ventricular cavity was entered under direct rtMRI guidance. Pigs underwent multiple injections with dilute gadolinium-DTPA. All myocardial segments were readily accessed. The active GCC and the passive Stiletto needle injector were readily visualized. More than 50 endomyocardial injections were performed with the aid of rtMRI; 81% were successful with this first-generation prototype. Conclusion — Percutaneous endomyocardial drug delivery is feasible with the aid of rtMRI, which permits precise 3-dimensional localization of injection within the LV wall.

The determination of fructosamine in serum of healthy newborns, children and adolescents by a new colorimetric method leads to an age-dependent reference range. Correction of the values for total protein yields a median of the results, which is not dependent on age and the upper limit of the reference range is not significantly different from that of healthy adults; this does not hold true for referral to albumin. As the half-life time of glycated serum proteins is shorter (mean 20 days) than that of hemoglobin A1c, fructosamine can provide useful additional informations about the diabetic control of children and adolescents (medium-term record of blood glucose).

Ziel: Die Pravalenz von postpartalem Diabetes nach Gestationsdiabetes (GDM) variiert zwischen 3–24%. Eine Durchfuhrung der postpartalen Glucosetoleranztests (ppOGTT) beschrankt auf Frauen mit hohem Risiko wurde die Compliance und die Kosteneffektivitat verbessern. Ziel unserer Studie war es, ein Modell zur Risikoeinschatzung fur persistierenden Diabetes mellitus zu entwickeln. Methodik: Bei 605 Frauen mit GDM wurden prospektiv maternale antenatale und den Diabetes betreffende Daten (und Glucosewerte der ppOGTTs) erhoben. Ergebnisse: Insgesamt hatten 132 (21,9%) der Frauen einen pathologischen ppOGTT. Es bestand ein signifikanter Unterschied zwischen Frauen mit normalem und pathologischem ppOGTT bezuglich des mutterlichen BMI, des Gestationsalters (GA) bei Diagnose, der Glucosewerte der antenatalen OGTTs, des GA bei Geburt, der Notwendigkeit einer Insulintherapie und der neonataler Makrosomie. In einer Multivarianzanalyse fanden wir 4 unabhangige Risikofaktoren: BMI ≥30kg/m2, GA bei Diagnose200mg/dl und die Notwendigkeit einer Insulintherapie. Die Pravalenz von pathologischen ppOGTTs wurde unter Einbeziehung der Anzahl der Risikofaktoren (RF) evaluiert: 0=9,2%(14/153), 1=13,4%(25/186), 2=28,5%(43/151), 3=45,6%(26/57), 4=68%(13/19). Wurden ppOGTTs auf Frauen mit ≥2RF beschrankt (40% der Studienteilnehmerinnen), musste mit 36,1% pathologischen oGTTs gerechnet werden, wahrend das Risiko bei Frauen mit 2 (13,4%). Zusammenfassung: Wenn ppOGTTs auf Frauen mit ≥2RF beschrankt wurden, konnten oGTTs bei 60% der Frauen eingespart werden und dennoch die Mehrzahl der Frauen mit postpartaler Glucoseintoleranz erkannt werden.