Impact of cardiovascular/diabetic comorbidity on conversion rate during laparoscopic cholecystectomy for acute cholecystitis: a multi-center study on early versus very delayed approach.

BACKGROUND: The impact of diabetes and cardiovascular comorbidity on laparoscopic cholecystectomy has been long debated, evaluating them as risk factors for conversion to an open procedure especially in patients with acute cholecystitis: an "early" procedure, as suggested by 2013 Tokyo guidelines, has been compared to a "very delayed" one in patients under anticoagulant/antiplatelet therapy or treated for diabetes and referred by medical wards to surgery after the acute period. METHODS: We selected 240 patients operated for acute cholecystitis by laparoscopy over the last 4 years at St. Orsola University Hospital-Bologna and Umberto I University Hospital-Rome, comparing 98 diabetic/cardiovascular patients versus 142 subjects as control group: the selection was based on operative timing, "early" (73 patients treated within 3 days) and "very delayed" (167 patients operated after 6 weeks). RESULTS: In the "early" subgroup there was no difference comparing diabetic/cardiovascular patients (31 pts) versus control group (42 pts) while in the "very delayed" subgroup among diabetic/cardiovascular patients (67 pts) there was significantly male predominance, ASA III/IV prevalence and less positive imaging findings versus control group (100 pts). In both subgroups, the conversion rate was significantly higher for diabetic/cardiovascular patients ("early"=25.8% and "very delayed"=8.95%) compared to control groups ("early"=4.76% and "very delayed"=1%), showing a trend (p=0.058) towards an increased conversion rate in the early approach among diabetic/cardiovascular group. CONCLUSIONS: Our study showed a significantly increased conversion rate to an open cholecystectomy for diabetic/cardiovascular patients affected by cholecystitis, especially within 3 days by the acute episode.

Colocutaneous fistula through ulcerative colitis and cancer to the pyoderma gangrenosum: a never-ending story for a single patient. Case report.

BACKGROUND: Inflammatory bowel diseases may be associated with many extraintestinal complications, that in some cases can represent the first onset of these disorders. In particular during the course of the disease, Ulcerative Colitis develops extraintestinal manifestations very frequently. One of the rarest is pyoderma gangrenosum, a noninfectious neuthrophilic dermatosis, that can involve most commonly legs but also other parts of the skin or mucosas. It can be idiopathic or associated with gammopathies, vasculitis, chronic arthritis or, like in our case, with inflammatory bowel disease and malignancies. CASE PRESENTATION: A 38-year-old man was referred to our Department with a colo-cutaneous fistula in the left quadrant of abdominal wall. In the anamnesis he reported a trauma during a soccer match three weeks before. Through a CT scan and endoscopy with biopsy an inflammatory bowel disease with a segmental colitis and stenosis was diagnosed. After medical therapy, an initial radiological drainage and a period of parenteral nutrition, he underwent a left hemicolectomy. Despite the previous endoscopic biopsy the histopathological examination put in evidence not only inflammatory disease (in particular Ulcerative Colitis) but also a colorectal tumor pT4pN0. After the full recovery before chemotherapy he has developed on the chest and on the abdomen some painful nodules, with central necrosis, one of those in contact with one of the ribs. Through TC and RM it was impossible to understand the precise nature of these skin lesions. With biopsy a pyoderma gangrenosum was diagnosed and treated until complete resolution. DISCUSSION AND CONCLUSION: Management of inflammatory bowel diseases can be a true challenge, not only for the intestinal manifestations, but also for all the other features not related to gut. In some cases the same patient can develop many complications, such as malignancies or rare cutaneous diseases. Despite the initial surprise for such a weird evolution in a same patient, from fistula to inflammatory disease to cancer and finally to pyoderma gangrenosum, to face every single complication following consolidated diagnostic and pathological paths has been the correct strategy for controlling the disease.

Laser ablation in biliary tree: analysis of the intraductal and superficial thermal effects during the treatment.

The treatment of choice for the unresectable cholangiocarcinoma is based on biliary decompression procedures. Despite stent placement is the standard of care, it is related to well-known complications. Hence, alternative techniques were proposed. Ideally, they should guarantee an adequate intraductal disobstruction, without injuring the surrounding tissues.This pre-clinical study aims to investigate the thermal effects of the laser ablation (LA) in the biliary tree, in terms of intraductal and surrounding tissue temperature achieved with different laser settings. The common bile ducts (in their upper and lower portions) of two pigs were ablated for 6 minutes with a diode laser at 3 W and 5 W. A custom-made laser applicator was used to obtain a circumferential ablation within the ducts. The intraductal temperature (Tid) was monitored by means of a fiber Bragg grating (FBG) sensor, while an infrared thermal camera monitored the T distribution in the surrounding tissues (Tsup). A maximum T difference of 65 °C and 57 °C was evidenced between the two power settings for the Tid measured in the upper and lower ducts, respectively. The mean difference between Tid and the averaged Tsup values was evaluated. At 5 W, a difference of 37±3 °C and 44±10 °C were obtained for the upper and lower ducts, respectively. At 3 W, a T difference of 2±1 °C was obtained for the upper biliary duct, while a difference of 8±1 °C was documented for the lower duct. Based on the results obtained in this preliminary study, the possibility to equip the laser probe with temperature sensor can improve the control and the safety of the procedure; this solution will guarantee the monitoring of the treatment while preserving the lumen and the surrounding structures.

The surgical management of acute bowel ischemia in octogenarian patients to avoid Short Bowel Syndrome: a multicenter study.

BACKGROUND: This is a multicenter study performed in two Italian tertiary care centers: General Emergency Surgery Unit at St. Orsola University Teaching Hospital - Bologna and Department of Surgical Sciences at Umberto I University Teaching Hospital - Rome. The aim was to compare the results of different approaches among elderly patients with acute bowel ischemia. METHODS: Sixty-three patients were divided in two groups: 1) DSgroup- 28 patients treated in Vascular Unit and 2) GEgroup- 35 patients treated in Emergency Surgery Unit. RESULTS: Mean age was 80 years, significantly higher for the GEgroup (p<0.001). Gender was predominantly female in both groups, without statistical difference. Pre-operatively, laboratory tests didn't show any difference in white blood cell count, serum lactate levels or serum creatinine among patients, while increase of c-reactive protein was observed in DSgroup with significant difference (p<0.001). The Romamain cause of acute bowel ischemia was embolism in DSgroup (p=0.03) and vascular spasm in GEgroup (p<0.001). On CT scan, bowel loop dilation was present in 58.7% of patients without statistical difference in both groups. The time lapse from diagnosis to operation didn't show significant differences between two groups (mean 349.4 min). Pre-operative heparin therapy was administered in DSgroup more frequently (p< 0.001). Among DS patients, thrombectomy was the most frequent procedure (19 patients) associated with bowel resection in 9 cases. In GEgroup, 22 patients had an explorative laparotomy (p<0.001), 8 had a bowel resection with anastomosis and 5 a bowel resection plus stoma. A second look was required more significantly in DSgroup (p<0.002). Post-operative morbidity affected significantly GEgroup (p=0.02). The 3-day survival was significantly higher in the DSgroup (p< 0.001). At discharge 32 patients (50.8%) were alive, 21 in DSgroup (p< 0.001). Only one patient among both groups (1.6%) developed a short bowel syndrome. CONCLUSIONS: In octogenarian patients with acute bowel ischemia, surgery should be always pursued whenever the interventional radiology is not assessed as a viable option. Both groups of patients showed an excellent outcome in terms of avoiding a short bowel syndrome. A multidisciplinary management by a dedicated team could offer the best results to prevent large intestinal resections.

The ERAS Protocol is at the forefront of the peri-operative pathway in colorectal surgery: monocentric clinical study.

INTRODUCTION: Colon cancer is one of the most common neoplastic diseases, with onset in old age; the benefits of the ERAS protocol were evaluated in the peri-operative treatment of patients affected by this neoplasm. METHODS: We studied 90 cases of colorectal neoplasia observed at the General Surgery UOC of the San Camillo de Lellis Hospital between September 2014 and April 2016, undergoing laparoscopic surgery and to which the ERAS protocol was applied; key points were the preoperative oral feeding, the epidural anesthesia, the reduced or failed hydro-electrolytic overload, the early mobilization and recovery of the feeding, the non-use of drainage. The most important parameers considered were the reduced duration of the operating hospital stay, the lower occurrence of early and distant complications. RESULTS: 85 surgical procedures were performed with laparoscopic technique (94.4%) and 5 with traditional open technique (5.6%). The conversion rate was 5.8% (5/85). 29 surgical procedures of right hemicolectomy (32.2%) and 26 of anterior resection of the rectum (28.9%) were performed; in another 29 patients (32.2%) an intervention with an open traditional technique was performed. A balanced anesthesia was performed in 41 patients (45.6%); epidural anesthesia in 32 cases (35.6%); the Tap Block in 17 subjects (18.9%). The average volume of liquid infusion was 1664cc ± 714; the average post-operative hospital stay of 4.3 ± 0.9 days. CONCLUSIONS: The ERAS protocol reduces the duration of the post-operative hospitalization, involves a lower incidence of precocious and remote complications, in particular if associated with a minimally invasive surgical method; it is easily applicable and reproducible in a hospital environment, with a marked reduction in healthcare management costs.

Colo-rectal endoscopic full-thickness resection (EFTR) with the over-the-scope device (FTRD®): A multicenter Italian experience.

BACKGROUND AND AIM: Endoscopic full-thickness resection(EFTR) with FTRD® in colo-rectum may be useful for several indications.The aim was to assess its efficacy and safety. MATERIAL AND METHODS: In this retrospective multicenter study 114 patients were screened; 110 (61M/49F, mean age 68 ±â€¯11 years, range 20-90) underwent EFTR using FTRD®. Indications were:residual/recurrent adenoma (39), incomplete resection at histology (R1 resection) (26), non-lifting lesion (12), adenoma involving the appendix (2) or diverticulum (2), subepithelial lesions(10), suspected T1 carcinoma (16), diagnostic resection (3). Technical success (TS: lesion reached and resected), R0 resection (negative lateral and deep margins),EFTR rate(all layers documented in the specimen) and safety have been evaluated. RESULTS: TS was achieved in 94.4% of cases. EFTR was achieved in 91% with lateral and deep R0 resection in 90% and 92%. Mean size of specimens was 20 mm (range 6-42). In residual/recurrent adenomas, final analysis revealed: low-risk T1 (11), adenoma with low-grade dysplasia (LGD) (24) and high-grade dysplasia (HGD) (3), scar tissue (1). Histology reports of R1 resections were: adenoma with LGD (6), with HGD (1), low-risk (6) and high-risk (1) T1, scar tissue (12). Non-lifting lesions were diagnosed as: adenoma with HGD (3), low-risk (7) and high risk (2) T1. Adverse clinical events occurred in 12 patients (11%),while adverse technical events in11%. Three-months follow-up was available in 100 cases and residual disease was evident in only seven patients. CONCLUSIONS: EFTR using FTRD® seems to be a feasible, effective and safe technique for treating selected colo-rectal lesions. Comparative prospective studies are needed to confirm these promising results.

Transoral video assisted thyroidectomy: a systematic review.

INTRODUCTION: The aim of this study is to perform a review of the English-language international literature concerning thyroid surgery performed through the transoral vestibular approach, to evaluate its flessibility and safety in terms of complications. MATERIALS AND METHOD: The review was carried out on 17 studies of 17 different Authors. The following variables were taken into consideration: first Author's name, nationality, year of publication, number of cases, hospital stay, conversion rate, type of surgical approach, total number of total thyroidectomies and loboisthmectomies, operative time range, intraoperative blood loss range, number and percentage of complications. RESULTS: 736 procedures were performed: 289 total thyroidectomies and 447 loboisthmectomies. Surgical approach was trivestibular in 15 cases and combined (oro-vestibular) in 2 cases. The operative time varies from 43 minutes for a loboisthmectomy to 345 for a total thyroidectomy. Intraoperative blood loss ranges from 3 to 300 ml. Ten cases were converted into open surgery. The hospital stay varies from 1 to 10 days. Complications were: transient recurrent laryngeal nerve palsy in 34 cases, permanent in 2 cases; transient hypoparathyroidism in 62 cases. One case of postoperative bleeding, 22 postoperative seroma, 20 cases of mental nerve injury, 8 cases of operative wound infection. CONCLUSIONS: Transoral endoscopic thyroidectomy vestibular approach (TOETVA) is a new surgical method, the use of which exclusively meets the aesthetic needs of some patients. Its specific complication is the injury of the mental nerves. Further studies, however, seem to be necessary, on numerically broader cases, to ascertain the real validity of the method.

Early versus delayed approach in cholecystectomy after admission to an emergency department. A multicenter retrospective study.

BACKGROUND: Discussion regarding the timing of cholecystectomy for acute cholecystitis is still ongoing. This study evaluates the outcomes of patients who underwent surgery for acute cholecystitis after emergency admission at St. Orsola University Hospital of Bologna and Umberto I Hospital La Sapienza University of Rome. PATIENTS AND METHODS: . We performed a retrospective study on 464 patients who underwent cholecystectomy for acute cholecystitis. We divided patients in three groups based on the time elapsed between the onset of symptoms and surgery: within 72 hours (Group A), between 72 hours and 6 weeks (Group B) and after 6 weeks (Group C). We performed both univariate and multivariate statistical analysis on the data collected. RESULTS: The best results were in Group C, with significant differences with the others two groups: higher rates of laparoscopic technique (93% of cases), no mortality, better morbidity and shorter hospital stay. On the contrary, no significant differences were observed between Groups A and B: laparoscopic cholecystectomy 67% vs 66%, morbidity (Clavien-Dindo III-IV) 5% vs 5%, mortality 2% vs 1%, hospital stay 6,6 vs 5,6 days. Conversion rate was 11% in Group A, 18% in Group B and 4% in Group C. CONCLUSION: Our experience shows better results for cholecystectomies performed after 6 weeks from the onset of symptoms, while earlier cholecystectomies have worse outcomes regardless if they are performed before or after 72 hours from the onset of symptoms.

Comparison of outcomes following intersphincteric resection vs low anterior resection for low rectal cancer: a systematic review.

BACKGROUND: Low Rectal Anterior Resection (LAR) is challenging when anal canal mucosa and/or internal sphincter are involved by very low tumors. In these cases, Intersphincteric resection (ISR) with the removal of the internal sphincter is designed to increase the distal margin of resection, thus preserving the external sphincter and pubo-rectalis muscle complex. Aim is to compare results after ISR with those of LAR, including subgroup analysis of open, laparoscopic and robotic ISR. METHODS: Studies published from January 1991 to January 2017 describing ISR and comparing results with LAR in adults were included irrespective of the technique. Tumor and surgical characteristics, clinical, functional and oncological results were collected. RESULTS: 25 non-randomized studies were included. Postoperative mortality ranged between 0% and 2.3%. The hospital stay ranged from 5 days to 40 days, lower in robotic ISR group if compared with laparoscopic ISR. Patients avoiding permanent stoma with ISR accept a lower continence level as satisfactory. Furthermore, anorectal function after ISR often tends to improve. ISR and LAR presented not statistically significant differences. Oncological outcomes were not statistically different Morbidity, blood loss and need for blood transfusions were lower in the laparoscopic ISR if compared with open approach. CONCLUSIONS: Morbidity could more frequently affect open ISR if compared with laparoscopic ISR. Functional outcomes were influenced by neoadjuvant CRT, but not by the surgical approach of reconstruction, while were positively influenced by partial ISR with respect to total ISR.

Laparoscopic cholecystectomy for acute cholecystitis: are intended operative approach, timing and outcome affected by BMI? A multicenter retrospective study.

BACKGROUND: Laparoscopy is the gold-standard for cholecystectomy after acute cholecystitis, but the issue is controversial in obese subjects. PATIENTS AND METHODS: We reviewed 464 patients operated for acute cholecystitis (59 open and 405 laparoscopic) over the last five years at St Orsola University Hospital-Bologna and Umberto I University Hospital-Rome, comparing retrospectively: 1) BMI < 30 (397 patients) and BMI =/> 30 (67 patients) and moreover 2) BMI < 25 (207 patients) and BMI =/> 25 (257 patients). RESULTS: In the first comparison, obese patients showed higher cardiovascular co-morbidity (61.1% vs 44.5%, p=0.01), worse symptoms (Murphy's sign positive in 92.5% vs 80.8%, p=0.02; fever >38.5°C in 88.0% vs 76.0 %, p=0.02) and significant radiologic imaging (95.5% vs 85.1%, p=0.01) of acute cholecystitis. Laparoscopy was used in 83.6% of obese patients vs 87.9% without any difference, and operative time or conversion rate were similar. According to Tokyo Guidelines 2013, the number of patients who underwent surgery within 3 days or after 6 weeks was similar without statistical difference between the two groups. Hospital stay, morbidity and mortality were similar. Complications were seen in 25.4% of obese patients vs 15.9% (p= 0.03), mainly represented by wound infections. The second comparison did show no difference between two groups BMI =/>25 and BMI < 25. CONCLUSIONS: Our retrospective multicenter study showed no difference related to intended operative approach, timing and outcome in higher BMI versus lower BMI patients operated for acute cholecystitis.

Reconnection surgery in adult post-operative short bowel syndrome < 100 cm: is colonic continuity sufficient to achieve enteral autonomy without autologous gastrointestinal reconstruction? Report from a single center and systematic review of literature.

A systematic bibliographic research concerning patients operated on for SBS was performed: inclusion criteria were adult age, reconnection surgery and SBS < 100 cm. Autologous gastrointestinal reconstruction represented an exclusion criteria. The outcomes of interest were the rate of total parenteral nutrition (TPN) independence and the length of follow-up (minimum 1 year) after surgery. We reviewed our experience from 2003 to 2013 with minimum 1-year follow-up, dealing with reconnection surgery in 13 adults affected by < 100 cm SBS after massive small bowel resection: autologous gastrointestinal reconstruction was not feasible. Three (out of 5168 screened papers) non randomized controlled trials with 116 adult patients were analysed showing weaning from TPN (40%, 50% and 90% respectively) after reconnection surgery without autologous gastrointestinal reconstruction. Among our 13 adults, mean age was 54.1 years (53.8 % ASA III): 69.2 % had a high stomal output (> 500 cc/day) and TPN dependence was 100%. We performed a jejuno-colonic anastomosis (SBS type II) in 53.8%, in 46.1% of cases without ileo-cecal valve, leaving a mean residual small bowel length of 75.7 cm. In-hospital mortality was 0%. After a minimum period of 1 year of intestinal rehabilitation, all our patients (100%) went back to oral intake and 69.2% were off TPN (9 patients). No one was listed for transplantation. A residual small bowel length of minimum 75 cm, even if reconnected to part of the colon, seems able to produce a TPN independence without autologous gastrointestinal reconstruction after a minimum period of 1 year of intestinal rehabilitation.

Surgery for post-operative entero-cutaneous fistulas: is bowel resection plus primary anastomosis without stoma a safe option to avoid early recurrence? Report on 20 cases by a single center and systematic review of the literature.

BACKGROUND: A review was performed on entero-cutaneous fistula (ECF) repair and early recurrence, adding our twenty adult patients (65% had multiple fistulas). METHODS: The search yielded 4.098 articles but only 15 were relevant: 1.217 patients underwent surgery. The interval time between fistula's diagnosis and operative repair was between 3 months and 1 year. A bowel resection with primary anastomosis was performed in 1.048 patients, 192 (18.3%) underwent a covering stoma: 856 patients (81.7%) had a fistula takedown in one procedure. RESULTS: The patients had 14.3% recurrence and 13.1% mortality rate. In our experience 75% were surgically treated after a period equal or above one year from fistula occurrence: surgery was very demolitive (in 40% remnant small bowel was less than 100 cm). We performed a bowel resection with a hand-sewn anastomosis (95%) without temporary stoma. In-hospital mortality was 0% and at discharge all were back to oral intake with 0% early re-fistulisation. CONCLUSIONS: Literature supports our experience: ECF takedown could be safely performed after an adequate period of recovery from 3 months to one year from fistula occurrence. In our series primary repair (bowel resection plus reconnection surgery without temporary stoma) avoided an early recurrence without mortality.

Tapered fiber optic applicator for laser ablation: Theoretical and experimental assessment of thermal effects on ex vivo model.

Laser Ablation (LA) is a minimally invasive technique for tumor removal. The laser light is guided into the target tissue by a fiber optic applicator; thus the physical features of the applicator tip strongly influence size and shape of the tissue lesion. This study aims to verify the geometry of the lesion achieved by a tapered-tip applicator, and to investigate the percentage of thermally damaged cells induced by the tapered-tip fiber optic applicator. A theoretical model was implemented to simulate: i) the distribution of laser light fluence rate in the tissue through Monte Carlo method, ii) the induced temperature distribution, by means of the Bio Heat Equation, iii) the tissue injury, by Arrhenius integral. The results obtained by the implementation of the theoretical model were experimentally assessed. Ex vivo porcine liver underwent LA with tapered-tip applicator, at different laser settings (laser power of 1 W and 1.7 W, deposited energy equal to 330 J and 500 J, respectively). Almost spherical volume lesions were produced. The thermal damage was assessed by measuring the diameter of the circular-shaped lesion. The comparison between experimental results and theoretical prediction shows that the thermal damage discriminated by visual inspection always corresponds to a percentage of damaged cells of 96%. A tapered-tip applicator allows obtaining localized and reproducible damage close to spherical shape, whose diameter is related to the laser settings, and the simple theoretical model described is suitable to predict the effects, in terms of thermal damage, on ex vivo liver. Further trials should be addressed to adapt the model also on in vivo tissue, aiming to develop a tool useful to support the physician in clinical application of LA.

D’Andrea’s disease (angiomegaly): a currently well-defined nosological entitys.

In 1997 D’Andrea et al. described a new nosological entity the characteristics of which consisted of lengthening, dilation and tortuosity of blood vessels, arteries or veins, less prominent, but also less circumscribed than an aneurysm. This condition does not necessarily imply specific aneurysm formation although aneurysms at multiple sites are a frequent observation. The term used by authors for angiomegaly of the venous system was venomegaly and the analogous condition of the arterial system was termed arteriomegaly. Although tortuosity and dilation of arteries and veins have been widely reported, suggesting a systemic disorder which affects the structural integrity of all vessels, most papers dealing with this intriguing condition did not describe any alterations in the components of vessel walls. In the present paper, the authors describe a well-defined condition, D’Andrea’s Disease (or DD, in this article), analyzing its salient morphological and clinical features and clarifying this pathological condition as a distinct and now well-defined nosological entity.

Pilonidal disease mimicking anterior anal fistula and associated with posterior anal fistula: a two-step surgery. Case report.

AIM: Anal fistula is a common disease originated from abscess according the cryptoglandular theory. A rare etiology is the pilonidal disease. In our case we observed a pilonidal disease mimicking an anterior perianal fistula, associated with another posterior anal fistula. CASE PRESENTATION: A 36-year old man was referred to our department with an anal fistula with an anterior opening. Despite the clinical examination and the endoanal ultrasound, only during the surgery we discovered the origin of the anterior fistula from a misdiagnosed pilonidal sinus. There was also a posterior anal fistula in communication with the same abscess of the anterior one. We performed a two-step surgery with a first fistulectomy of the anterior tract, a drainage of abscess and the positioning of a seton for the posterior fistula. After about one month and the fall of the seton we evaluate the good healing of posterior anal fistula and excised the residual pilonidal sinus. CONCLUSION: This misdiagnosed pilonidal disease created in our clinical report a true challenge. Our goal was to eliminate as much disease as possible, but also to avoid major complications or recurrences. We refused an aggressive approach and chose a two-step surgery, with in the first approach not only a demolitive time but also a reconstruction to facilitate healing, and in the second time the complete eradication of the pathology.

Temperature monitoring during radiofrequency ablation of liver: in vivo trials.

Radiofrequency ablation (RFA) is a minimally invasive procedure used to treat tumors by means of hyperthermia, mostly through percutaneous approach. The tissue temperature plays a pivotal role in the achievement of the target volume heating, while sparing the surrounding healthy tissue from thermal damage. Several techniques for thermometry during RFA are investigated, most of them based on the use of single-point measurement system (e.g., thermocouples). The measurement of temperature map is crucial for the real-time control and fine adjustment of the treatment settings, to optimize the shape and size of the ablated volume. The recent interest about fiber optic sensors and, among them, fiber Bragg gratings (FBGs) for the monitoring of thermal effects motivated further investigation. In particular, the feature of FBGs to form an array of several elements, thus to be inscribed within the same fiber, allows the use of a single probe for the multi-points monitoring of the tissue temperature during RFA. Hence, the aim of this study is the development and characterization of a needle-like probe embedding an array of three FBGs, which was tested on pig liver during in vivo trials. The needle allows a safe and easy insertion of the fiber optic within the liver. It was inserted by ultrasound guidance into the liver, and monitored the change of tissue temperature during RFA controlled by the roll-off technique. Also the measurement error induced by breathing movements of the liver was assessed (less than 3 °C). Results encourage the use of the probe in clinical settings, as well as the improvement of some features, e.g., a higher number of FBGs for performing quasi-distributed measurement.

Multipoint temperature monitoring in liver undergoing computed tomography-guided radiofrequency ablation with fiber Bragg grating probes.

In this work, we investigated the temperature increment experienced by biological tissue during radiofrequency ablation (RFA). The measurements were performed by using two custom-made thermal probes based on fiber optic sensors (fiber Bragg gratings, FBGs). The two probes embed a total of 9 FBGs. Experiments were performed during RFA of an ex vivo healthy porcine liver. The RFA heating module was equipped with 5 thermocouples. Results show that the temperature increment close to the applicator (i.e., 0.6 cm-0.7 cm) reaches the temperature which is set as a target on the RFA module (i.e., approximately 100 °C). The distance from the applicator also has an impact on the dynamics of the heating phenomenon: at short distances the tissue temperature reaches a steady state condition after a few minutes, on the other hand the sensors placed at a distance ≥2cm did not reach the steady-state conditions during the 14-minute procedure. The multipoint temperature monitoring, which uses sensors at several distances from the applicator, can provide useful information regarding the boundary of damaged volume. This approach can be combined with the monitoring temperature system embedded in the heating equipment, to better control the damaged volume, and to improve the treatment outcomes.

Magnetic resonance-based thermometry during laser ablation on ex-vivo swine pancreas and liver.

Laser Ablation (LA) is a minimally-invasive procedure for tumor treatment. LA outcomes depend on the heat distribution inside tissues and require accurate temperature measurement during the procedure. Magnetic resonance imaging (MRI) allows a non-invasive and three-dimensional thermometry of the organ undergoing LA. In this study, the temperature distribution within two swine pancreases and three swine livers undergoing LA (Nd:YAG, power: 2 W, treatment time: 4 min) was monitored by a 1.5-T MR scanner, utilizing two T1-weighted sequences (IRTF and SRTF). The signal intensity in four regions of interest, placed at different distances from the laser applicator, was related to temperature variations monitored in the same regions by twelve fiber Bragg grating sensors. The relationship between the signal intensity and temperature increase was calculated to obtain the calibration curve and to evaluate accuracy, sensibility and precision of each sequence. This is the first study of MR-based thermometry during LA on pancreas. More specifically, the IRTF sequence provides the highest temperature sensitivity in both liver (1.8 ± 0.2 °C(-1)) and pancreas (1.8 ± 0.5 °C(-1)) and the lowest precision and accuracy. SRTF sequence on pancreas presents the highest accuracy and precision (MODSFRT = -0.1 °C and LOASFRT = [-2.3; 2.1] °C).

Goniometric measurement for the estimation of anisotropy coefficient of human and animal pancreas.

Estimation of optical properties of biologic tissues is determinant for laser dosimetry in medical applications. Tissues highly absorb and scatter the light in near infrared spectrum, where the laser provides therapeutic effects. Novel frontiers of clinical practice, e.g., the employment of laser light for the treatment of pancreatic cancer, require information about pancreas-laser interaction, which are crucial for therapy management. The property of biological tissues to scatter the light traveling through is described by the anisotropy coefficient (g). The relationship between g and the angular distribution of the scattered light is described by Henyey-Greenstein phase function. The measurement of angular distribution of scattered light is performed by the goniometric technique. This paper describes the estimation of g of ex vivo pancreas at 1064 nm, performed by a goniometric-based system, where a photodetector measures intensities of scattered light at fixed angles between -120° and 120°. A two-term Henyey-Greenstein phase function has been employed to estimate anisotropy coefficient for forward (gfs) and backward scattering (gbs). Experimental trails were performed to assess the repeatability of measurement system: percentage value of standard deviation is generally lower than 8% for angles higher (lower) than 13° (13°). Measurements were performed for the first time on healthy swine pancreas, aiming to investigate the influence of coagulation temperature: gfs decreases from 0.94 (at 25 °C) to 0.93 (at 80 °C). Afterwards, the same set up has been employed for the estimation of g of human pancreas affected by neuroendocrine tumor, which presented an estimated values for gfs of 0.89.

Metachronous elastofibromas.

Elastofibroma Dorsi (EFD) is a rare pseudo-tumor characterized by the overgrowth of elastic fibers mixed to adipose and connective tissues typically growing in the subscapular region. This can be bilateral but only rarely synchronous affecting different anatomical sites at the same time. Hereby we present a case of a 42-year-old male patient found with three different metachronous elastofibromas: bilateral EFD and a further third localization by the right elbow. The two EFs in the subscapular region were resected. After surgery pain reoccurred on the right side. This required the implantation of a spinal electro-stimulator. The elbow lesion was not excised as it was asymptomatic.