Intraoperative blood vessel detection and quantification: a Monte Carlo study

With better surgical outcomes, quicker recovery times, decreased postoperative pain, and reduced scarring at the surgical site, the application of minimally invasive surgery (MIS) has gained a lot of prominence in the last 30 years. This change in surgical practice has taken away the ability of a surgeon to palpate for the presence of a blood vessel as would occur in an open procedure. They instead must rely on a laparoscopic video camera feed that unfortunately cannot detect the presence of a blood vessel hidden beneath tissue. In certain scenarios, a surgeon can accidentally cut a blood vessel, which can lead to severe, even fatal, complications. Here, we show that by adding a near-infrared LED and a photodiode onto the opposing jaws of laparoscopic graspers, blood vessels buried under tissue can be detected. We show the results of Monte Carlo simulations to support our theory that the blood vessels ranging from 3 to 6 mm buried under up to 1 cm of tissue can be detected and quantified. This technology could be added to already existing laparoscopic tools that have limited surface areas on the jaws to assist surgeons during MIS procedures.

Blood vessel detection, localization and estimation using a smart laparoscopic grasper: a Monte Carlo study

For centuries, surgeons have relied on their sense of touch to identify vital structures such as blood vessels in traditional open surgery. Over the past two decades, surgeons have shifted to minimally invasive surgical (MIS) approaches, including laparoscopic surgery, which include benefits such as less scarring, less risk for infection, and quicker recovery times. In fact, some surgeries such as cholecystectomies have seen more than an 80% adoption of this technique because of those benefits. However, due to the fundamental challenges associated with using laparoscopic surgery, there has been a lower adoption in more complex specialties, such as colorectal and thoracic surgery, where the field of surgery has bleeding, fat, scar tissue, and adhesions. These problems are exacerbated by complicating factors such as inflammation, cancer, chronic disease, obesity, and re-operations. Importantly, surgeons will often convert from laparoscopy to open surgery if they can no longer proceed using the minimally invasive approach because of issues described with these complicating factors, thereby negating the benefits that the patient would have seen. When the surgeon does attempt these procedures with those issues, the surgery takes on average 30 min - 1 hour longer. A new method by which surgeons can visualize structures like blood vessels could reduce the conversion rates and operating time, thereby driving a greater adoption of laparoscopic surgery in these complex procedures. Here, we show that by adding near infrared (NIR) LEDs and a linear image sensor onto the opposing jaws of the laparoscopic graspers, blood vessels that are embedded within tissues can be detected and localized efficiently, even those not visible using current imaging techniques. We show the results of Monte Carlo simulations to support our claim, including that blood vessels ranging from 2 to 6 mm and buried under up to 1 cm of tissue can be detected. We also report developing a smart grasper handheld prototype to run ex vivo experiments. The results of these experiments matched with those of the Monte Carlo simulations and the estimated blood vessel size showed a strong correlation with the actual size. This technology will be incorporated into already existing laparoscopic tools to assist surgeons during MIS procedures.

Diagnostic use of intramedullary reaming biopsy in metastatic long bone disease

INTRODUCTION Bone is the third most common site of metastasis. A histological diagnosis is important in guiding therapy and prognosis. In up to 15% of cases of metastatic disease, the primary tumour remains unknown. This emphasises the importance of adequate, reliable and accurate sampling when performing any type of biopsy. Reaming biopsy is commonly performed during intramedullary nailing of metastatic long-bone disease but there is little published evidence on the diagnostic use and reliability of this technique. AIMS AND METHODS We reviewed 49 cases of confirmed metastatic bone disease to determine adequacy for analysis, diagnostic accuracy and factors affecting reliability. RESULTS Adequate tissue for histopathological analysis was obtained in 96% of cases but metastasis was confirmed in only 51% of cases. The presence of a pathological fracture had no effect on accuracy of the results but metastasis was more likely to be missed in the presence of tissue crushing and or necrosis (P = 0.015). DISCUSSION This study determines the use and accuracy of bone reaming biopsy in metastatic disease and, to the best of our knowledge, is the only study determining the effect of additional factors such as the presence of a pathological fracture and tissue necrosis or crushing on the diagnostic accuracy of this technique. CONCLUSIONS In spite of adequate tissue sampling, the diagnostic accuracy and, hence, reliability of intramedullary reaming biopsy in metastatic bone disease is less than optimal. A reaming histopathology report suggesting no evident metastasis should always be taken in clinical context.

Effect of green coffee extract on rheological, physico-sensory and antioxidant properties of bread

Green coffee extract, GCE (Coffee canephora) was used at 1.0, 1.5 and 2.0% levels for making bioactive rich bread. The processed GCE from the green coffee beans had 21.42% gallic acid equivalents (GAE) total polyphenols (TPP), 37.28% chlorogenic acid (CGA) and 92.73% radical scavenging activity (RSA), at 100 ppm concentration of GCE and caffeine content (1.75%). Rheological, physico-sensory and antioxidant properties of GCE incorporated breads were analysed and compared with control bread. The results revealed not much significant change in the rheological characteristics of dough up to 1.5% level; an increase in bread volume; greenness of bread crumb and mostly unchanged textural characteristics of the bread with increased addition of GCE from 0 to 2.0%. Sensory evaluation showed that maximum level of incorporation of GCE without adverse effect on the overall quality of bread (especially taste) was at 1.5% level. The contents of TPP, RSA and CGA increased by 12, 6 and 42 times when compared to control bread and had the highest amount of 4-5 caffeoylquinic acid.

Acute myeloid leukemia derived from lympho-myeloid clonal hematopoiesis

We studied acute myeloid leukemia (AML) patients with lympho-myeloid clonal hematopoiesis (LM-CH), defined by the presence of DNA methyltransferase 3A (DNMT3A) mutations in both the myeloid and lymphoid T-cell compartment. Diagnostic, complete remission (CR) and relapse samples were sequenced for 34 leukemia-related genes in 171 DNMT3A mutated adult AML patients. AML with LM-CH was found in 40 patients (23%) and was associated with clonal hematopoiesis of indeterminate potential years before AML, older age, secondary AML and more frequent MDS-type co-mutations (TET2, RUNX1 and EZH2). In 82% of AML patients with LM-CH, the preleukemic clone was refractory to chemotherapy and was the founding clone for relapse. Both LM-CH and non-LM-CH MRD-positive AML patients who achieved CR had a high risk of relapse after 10 years (75% and 75%, respectively) compared with patients without clonal hematopoiesis in CR with negative MRD (27% relapse rate). Long-term survival of patients with LM-CH was only seen after allogeneic hematopoietic stem cell transplantation (HSCT). We define AML patients with LM-CH as a distinct high-risk group of AML patients that can be identified at diagnosis through mutation analysis in T cells and should be considered for HSCT.

An unusual case of lipoma arborescens

Introduction Lipoma arborescens is a rare condition of the synovial lining. It is particularly uncommon in the bicipitoradial bursae of the elbow. Case Report A 68-year-old woman presented with a 5-month history of anterior elbow pain and swelling causing discomfort. Radiography demonstrated reactive changes of radial tuberosity and magnetic resonance imaging confirmed lipoma arborescens of the bicipitoradial bursa with distal biceps tendinopathy. A bicipital bursa bursectomy and lipoma excision was performed. Gross pathology and histology was consistent with lipoma arborescens. Three months postoperatively, our patient had full range of motion and good strength. Conclusions To our knowledge, this is the first published case report of lipoma arborescens affecting the elbow. Recognising the differential diagnoses of anterior elbow pain and the characteristic imaging is essential for accurate diagnosis.

Chronic Recurrent Multifocal Osteomyelitis: A Diagnostic Dilemma: A Case Report and Review of the Literature

CASE

Chronic recurrent multifocal osteomyelitis, a misnomer in itself, is a rare disorder that presents infrequently to orthopaedic units. The differential diagnosis is wide, including neoplastic lesions and infection, which may lead to unnecessary interventional and surgical procedures. We present a case that exhibited the hallmark features of this condition-recurrent, multifocal, aseptic osteitis in a 9-year-old girl-and our rationalized management including imaging, nonsteroidal anti-inflammatory drugs, and bisphosphonates.

CONCLUSION

With increased awareness by orthopaedic surgeons, patients may be diagnosed and managed appropriately, enabling a benign course and limiting morbidity.

Constitutive IRF8 expression inhibits AML by activation of repressed immune response signaling

Myeloid differentiation is blocked in acute myeloid leukemia (AML), but the molecular mechanisms are not well characterized. Meningioma 1 (MN1) is overexpressed in AML patients and confers resistance to all-trans retinoic acid-induced differentiation. To understand the role of MN1 as a transcriptional regulator in myeloid differentiation, we fused transcriptional activation (VP16) or repression (M33) domains with MN1 and characterized these cells in vivo. Transcriptional activation of MN1 target genes induced myeloproliferative disease with long latency and differentiation potential to mature neutrophils. A large proportion of differentially expressed genes between leukemic MN1 and differentiation-permissive MN1VP16 cells belonged to the immune response pathway like interferon-response factor (Irf) 8 and Ccl9. As MN1 is a cofactor of MEIS1 and retinoic acid receptor alpha (RARA), we compared chromatin occupancy between these genes. Immune response genes that were upregulated in MN1VP16 cells were co-targeted by MN1 and MEIS1, but not RARA, suggesting that myeloid differentiation is blocked through transcriptional repression of shared target genes of MN1 and MEIS1. Constitutive expression of Irf8 or its target gene Ccl9 identified these genes as potent inhibitors of murine and human leukemias in vivo. Our data show that MN1 prevents activation of the immune response pathway, and suggest restoration of IRF8 signaling as therapeutic target in AML.

Effect of gabapentin premedication on preoperative anxiety and postoperative pain

Background: In addition to chronic pain and anxiety disorders, few studies have found promising role of gabapentin in relieving acute postoperative pain as well as acute anxiety too. Objectives: To evaluate the effect of gabapentin premedication on preoperative anxiety and postoperative pain in patients undergoing elective open cholecystectomy. Methods: A prospective, randomized, double blind and placebo controlled study. Eighty adult patients of ASA I and II were divided into 2 groups of 40 each. Patients in group 1 and group 2 received capsules Gabapentin (1200mg) or identical placebo capsules 2 hours prior to surgery respectively. Preoperative anxiety and 12 hours postoperative pain was assessed using Anxiety and Pain VAS score respectively along with the observation of side effects. Postoperatively, intravenous pethidine 0.5 mg/kg was given when pain VAS > 40mm and time to first pethidine injection and total pethidine consumption in 12 hours was recorded. Results: Anxiety VAS scores after one hour of drug intake (35.75±20.11 versus 46.63±12.73) and just before induction of anaesthesia (45.75±30.27versus 68.13±29.84) along with postoperative Pain VAS scores were significantly lower in gabapentin group. Time to the first pethidine demand was significantly longer (145.34±194.54 min versus 26.30±51.02min) and cumulative pethidine consumption throughout study period was also significantly lower (35.91 ± 16.61 versus 57.84 ± 20.72mg) in gabapentin group. Conclusions: 1200 mg gabapentin premedication in open cholecystectomy patients significantly reduced preoperative anxiety, postoperative pain and total pethidine consumption with negligible side effects. DOI: http://dx.doi.org/10.3126/hren.v11i3.9642 Health Renaissance 2013;11(3):254-259

Locked-in syndrome during stellate ganglion block

Intra-arterial injection of a local anaesthetic during stellate ganglion blockade may cause life-threatening complications. The usual complications are apnoea, unconsciousness and seizures. However, occasionally an unusual complication, ‘locked-in’ syndrome, has also been reported. In this syndrome the patients remain conscious despite their inability to move, breathe or speak. Here we describe a patient who developed features akin to the locked-in syndrome along with severe hypotension and bradycardia, after an injection of only 2 ml of lignocaine during a stellate ganglion block.