Fernando Dip - Academia.edu (original) (raw)

Papers by Fernando Dip

part of the material is concerned, specifi cally the rights of translation, reprinting, reuse of ... more part of the material is concerned, specifi cally the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfi lms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specifi c statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use.

Midgut volvulus as initial presentation of pneumatosis cystoides intestinalis

ANZ Journal of Surgery, 2015

Pneumatosis cystoides intestinalis (PCI) is a rare disease with unknown aetiology. It is characte... more Pneumatosis cystoides intestinalis (PCI) is a rare disease with unknown aetiology. It is characterized by the presence of gas-filled cysts within the submucosa or subserosa of the intestine; however, it can be located in any part of the intestinal tract. The pathogenesis, although unknown, seems to be related to the mucosal breakdown and bacterial fermentation. PCI is associated with a variety of diseases in which there is loss of bowel mucosal integrity and/or increased intraluminal pressure. PCI is usually incidentally discovered during diagnostic modalities being carried out for other reasons. In approximately 16% of cases, PCI presents as intestinal obstruction or perforation. Patients commonly present with non-specific gastrointestinal symptoms such as intermittent abdominal pain, nausea, and in cases with colonic involvement, diarrhoea, mucus discharge, rectal bleeding and constipation. Although previously PCI was thought to occur more frequently in the small intestine, more recent studies have shown that PCI appears more frequently in the colon (61.8%), followed by the small intestine (15.4%). A 72-year-old woman presented to the emergency department with a 3-week history of severe back pain with radiation to the abdomen and now recent onset of vomiting. On examination, the vital signs were normal and the abdomen was soft with only minimal tenderness without any peritoneal signs. Laboratory values were also within normal limits. An initial computed tomography (CT) scan without contrast was read as free intra-abdominal air under the right hemidiaphragm (Fig. 1). Because of the overall paucity of clinical signs, a CT with contrast was obtained. The CT scan with oral contrast revealed a large duodenum diverticulum in the right upper quadrant and suggested a possible internal hernia; small pockets of free air were again visualized (Fig. 2). At this point, the patient was taken to the operating room for diagnostic laparoscopy. During laparoscopic exploration, at a distance of about 40 cm from the ligament of Treitz, the small bowel was twisting on itself going under the superior mesenteric artery. The internal hernia was reduced by gentle traction. Once this was accomplished, it became evident that a segment of bowel that was folding on itself contained multiple diverticula. There was no evidence of inflammatory changes, but there appeared to be air under the layer of visceral peritoneum. Since those diverticula had functioned as a lead point for the torsion, the segment of bowel was resected (35 cm) (Fig. 3) with a linear stapler. A standard side-to-side functional end-to-end anastomosis was performed. She was discharged home on postoperative day 4 tolerating regular diet. The pathology report revealed the following: small bowel segment with diverticular disease and serosal adhesions. Histological changes were consistent with arteriovascular malformation and severe atherosclerosis. Seven reactive lymph nodes were negative for neoplasm. In this unusual case report, the clinical presentation was of a volvulus around the superior mesenteric artery, likely secondary to the bulky PCI in the jejunum. To our knowledge, this is the first description of such a presentation of PCI. This underlies the importance of a complete clinical evaluation that does not only take into account the radiological findings. The initial CT scan in our case

Randomized Trial of Near-infrared Incisionless Fluorescent Cholangiography

Annals of Surgery, 2019

Background: Incisionless near-infrared fluorescent cholangiography (NIFC) is emerging as a promis... more Background: Incisionless near-infrared fluorescent cholangiography (NIFC) is emerging as a promising tool to enhance the visualization of extrahepatic biliary structures during laparoscopic cholecystectomies. Methods: We conducted a single-blind, randomized, 2-arm trial comparing the efficacy of NIFC (n = 321) versus white light (WL) alone (n = 318) during laparoscopic cholecystectomy. Using the KARL STORZ Image1 S imaging system with OPAL1 technology for NIR/ICG imaging, we evaluated the detection rate for 7 biliary structures—cystic duct (CD), right hepatic duct (RHD), common hepatic duct, common bile duct, cystic common bile duct junction, cystic gallbladder junction (CGJ), and accessory ducts —before and after surgical dissection. Secondary calculations included multivariable analysis for predictors of structure visualization and comparing intergroup biliary duct injury rates. Results: Predissection detection rates were significantly superior in the NIFC group for all 7 biliary ...

Fluorescent View of Safety During Laparoscopic Cholecystectomy

Journal of the American College of Surgeons, 2016

Journal of the American College of Surgeons, 2016

Identification of parathyroid glands may be challenging during thyroid and parathyroid surgery. A... more Identification of parathyroid glands may be challenging during thyroid and parathyroid surgery. Accidental resection of the glands may increase the morbidity of the surgery. The aim of this study was to evaluate accuracy in identification of autofluorescent parathyroid glands with the use of near infrared light in real time. Patients undergoing thyroid and parathyroid surgery between June and August 2015 were included in the study. During the procedure, the surgical field was exposed to near infrared laser light in order to analyze the intensity of the fluorescence of different tissues (parathyroid glands, thyroid glands, and background). Surgical images were recorded and analyzed. Twenty-eight patients were included in the study. Nineteen patients were women and 9 were men. Seven patients had primary hyperparathyroidism, 4 had hyperthyroidism, 3 had goiters, and 11 had thyroid cancer. Three patients had mixed pathologies, including 2 patients with thyroid cancer and primary hyperpa...

Determination in the optimal time of administering intravenous indocyanine green in fluorescent cholangiography

Journal of the American College of Surgeons, 2015

VITOM II: A prototype for fluorescent image guided surgery implementation in open surgery

Journal of the American College of Surgeons, 2015

Neck Cancer: Imaging Techniques and Progress on the Operative Approach

Technological Advances in Surgery, Trauma and Critical Care, 2015

Treatment of head and neck cancer has undergone considerable advances and requires multidisciplin... more Treatment of head and neck cancer has undergone considerable advances and requires multidisciplinary approach that embraces surgery, radiotherapy, and chemotherapy. Nevertheless, the 5-year survival rate is only 50 % after recurrence, lymph node involvement, and metastatic disease. We discuss head and neck cancer genetics and molecular progress, advances in diagnostics, and an emphasis is placed on treatment such as surgical procedures and applicable technologies.

Obesity Surgery, 2015

Background Fluorescence cholangiography represents an incisionless technique that can be applied ... more Background Fluorescence cholangiography represents an incisionless technique that can be applied during laparoscopic cholecystectomy to visualize bile ducts. Our objective was to evaluate and detect variances of fluorescence imaging in obese and non-obese patients. Methods Prospective patients were selected for laparoscopic cholecystectomies. Subjects were divided into groups based on their body mass index. Fluorescence imaging was applied preceding any dissection of extrahepatic ducts and again after dissection. Positive and negative identifications of biliary ducts were recorded. Results Seventy-one patients participated, with 53.5 % classified as obese. The cystic, hepatic, common bile duct, and accessory ducts were identified as follows: 100, 70.4, 87.3, and 7.0 % of patients, respectively. No differences in hepatic duct, common bile duct, and accessory duct visualization were detected in the obese and non-obese groups (p value 0.09, 0.16, and 0.66, respectively). Conclusions Fluorescent cholangiography is a useful technique in the obese and non-obese population. Obesity does not affect fluorescence visualization of bile ducts.

Past, Present, and Future of Fluorescence

Fluorescence Imaging for Surgeons, 2015

It is important to define fluorescence. There are several ways to describe this term: (1) the emi... more It is important to define fluorescence. There are several ways to describe this term: (1) the emission of electromagnetic radiation, especially of visible light, stimulated in a substance by the absorption of incident radiation and persisting only as long as the stimulating radiation is continued. (2) Emitting light during exposure to radiation from an external source. (3) Luminescence that is caused by the absorption of radiation at one wavelength followed by nearly immediate reradiation usually at a different wavelength and that ceases almost at once when the incident radiation stops. The common denominators for this term are a source of radiation, the absorption of this radiation, and the emission of a modified radiation that ends immediately as the source stops emitting radiation. Chemically speaking, fluorescence is brought about by absorption of photons in the singlet ground state promoted to a singlet excited state. The spin of the electron is still paired with the ground state electron. As the excited molecule returns to ground state, it involves the emission of a photon of lower energy, which corresponds to a longer wavelength, than the absorbed photon and therefore lower energy, than the absorbed radiation.

Ureter Identification Using Methylene Blue and Fluorescein

Fluorescence Imaging for Surgeons, 2015

The use of a multimodal optical system that expands the surgeon’s light spectrum of view can impr... more The use of a multimodal optical system that expands the surgeon’s light spectrum of view can improve surgical performance making structures clearly visible during laparoscopic and open surgery. This allows for shorter procedural duration and improved prevention and incidence of ureteral injury associated with complex pelvic surgery. Optical imaging using invisible NIR fluorescent light has several advantages over currently available intraoperative techniques. First, visualization of the ureters does not require ionizing radiation, and uses only safe wavelengths of light for ample excitation. Secondly, because fluorescence emission is invisible to the human eye, the surgical field is not stained or changed in any way. The blue dyes that are currently used stain the surgical field and have relatively poor contrast. Thirdly, imaging can be performed in real-time (up to 15 frames per second) with the merged image from the color video and NIR fluorescent cameras providing anatomical landmarks that are easily identifiable. More work is needed to identify the optimal contrast agent and light wavelength with which it is most optimally visualized. Overall, this field of knowledge is of great interest and reports a great growing potential.

Surgical Endoscopy, 2015

Background Incisional hernias remain a significant complication of abdominal surgeries. Primary c... more Background Incisional hernias remain a significant complication of abdominal surgeries. Primary closure of the hernia defect has been suggested to improve long-term abdominal wall function. However, this can be technically challenging and time consuming. This study describes laparoscopic use of non-absorbable barbed sutures in primary closure of hernia defects in addition to intraperitoneal mesh. Methods Patients who underwent laparoscopic primary ventral hernia repair with mesh were prospectively reviewed. Two groups were defined: Operations performed with barbed sutures for primary closure in addition to mesh and operations with only mesh without defect repair. The surgical technique involved running the hernia defect with a 2-polypropylene non-absorbable unidirectional barbed suture and subsequently fixing the mesh intraperitoneally with tacks. In both groups, a single transfascial centering suture was also utilized. Results Twenty-eight cases with barbed suture and mesh reinforcement and 29 cases with mesh-only were identified. The average dimensions of the ventral hernia defects were 57.8 (6-187) and 44.6 cm 2 (9-156) in the barbed suture with mesh and mesh-only group, respectively, p = 0.23. Median operating time was 78 min (range 35-187 min) in the barbed suture with mesh group versus 62 min (34-155 min) in the mesh-only group, p = 0.44. The median suturing time of closing the ventral hernia defect was 16 min (11-24 min). There were no differences in the pain scores. Mean follow-up for both groups was 8.2 ± 3.6 months (1-17 months) with one hernia recurrence in the mesh-only group, p = 0.41. Conclusions The barbed suture closure system could be used for rapid and effective primary defect closure in laparoscopic ventral hernia repair in addition to intraperitoneal mesh placement. No significant difference in operating time was detected when compared to the mesh-only approach. Further evidence to support these findings and longer follow-up periods is warranted to evaluate shortand long-term complications.

Impact of controlled intraabdominal pressure on the optic nerve sheath diameter during laparoscopic procedures

Surgical Endoscopy, 2015

Acute elevations of intraabdominal pressure (IAP) are seen in many clinical scenarios with a cons... more Acute elevations of intraabdominal pressure (IAP) are seen in many clinical scenarios with a consequent elevation in intracranial pressure (ICP). With the optic nerve sheath (ONS) being a part of the dura mater and the optic nerve surrounded by cerebral spinal fluid, a change in pressure within the subarachnoid space would be detected by ultrasonography, and invasive methods could be avoided. The study objective was to evaluate ultrasonographic modifications observed on the optic nerve sheath diameter during acute elevations of IAP in patients undergoing laparoscopic procedures. We prospectively collected data from patients who underwent laparoscopic procedures between July and August 2013. The optic nerve sheath diameter was measured sagittally with a 12-MHz transducer. The measurements were obtained at baseline, 15 and 30 min, and at the end of surgery. There were 16 females (36.4 %) and 28 males (63.6 %), with a mean age of 44.22 ± 10.44 years (range 23-66) and body mass index of 29.45 ± 6.53 kg/m(2) (range 21-39). The mean optic nerve sheath diameter was 4.8 ± 1.0 mm at baseline, 5.5 ± 1.1 mm at 15 min, 5.9 ± 1.0 mm at 30 min, and 5.1 ± 1.2 mm after deflation of pneumoperitoneum. The diameter increased significantly at 15 min by a median of 0.6 mm (interquartile range 0.3, 0.8; p < 0.0001) and at 30 min by a median of 1.0 mm (interquartile range 0.7, 1.4; p < 0.0001), returning close to baseline after surgery. The acute elevation in IAP during laparoscopy significantly increased the optic nerve sheath diameter. The changes in the ONSD reflect a temporary and reversible increase in the ICP due to the acute elevation of IAP.

The use of mechanical stapling devices in laparoscopic appendectomies has become a common practic... more The use of mechanical stapling devices in laparoscopic appendectomies has become a common practice. Occasionally, the retained staples have been described to cause adhesions that might result in bowel obstruction. Early bowel obstruction after routine abdominal surgery should be closely investigated and might warrant early re-exploration. We present a rare case of small bowel obstruction caused by a staple line adhesive band one week after appendectomy. A 46-year-old female underwent laparoscopic appendectomy for uncomplicated appendicitis. A linear endoscopic stapling device was utilized during the procedure. The patient was discharged without complication. One week later, the patient presented to the emergency room for abdominal pain and she was discharged after adequate pain control. Several hours later she returned with similar symptoms, and she was diagnosed with distal small bowel obstruction by computed tomography scan. During the diagnostic laparoscopy there was an internal hernia through a defect created by the appendiceal staple line and the adjacent small bowel mesentery. After reduction of the hernia, the small bowel venous drainage improved, and no intestinal resection was necessary. The offending staple was removed and the staple line covered with omentum. The patient had complete resolution of symptoms and she was discharged the following day. No perioperative complications occurred. Mechanical staplers are routinely used in laparoscopic appendectomy. The staple line should be inspected at the end of the procedure to confirm the absence of free, unformed staples that can generate adhesions and postoperative complications.

Cost analysis and effectiveness comparing the routine use of intraoperative fluorescent cholangiography with fluoroscopic cholangiogram in patients undergoing laparoscopic cholecystectomy

Surgical Endoscopy, 2014

Sensory Evaluation of the Nipple-Areolar Complex Following Primary Breast Augmentation: A Comparison of Incision Approaches

Aesthetic Surgery Journal

Background The central inframammary incisional approach for breast augmentation surgery disrupts ... more Background The central inframammary incisional approach for breast augmentation surgery disrupts the fifth anterior intercostal (AIC) nerve-artery-vein-plexus. Objectives The authors hypothesized that preservation of the fifth AIC neurovascular pedicle might completely preserve nipple areola complex (NAC) sensitivity after implant breast augmentation. The aim of the study was to analyze if the use of a laterally displaced incision is related with better sensitivity results than the conventional median sub-mammary incision in females who underwent primary breast augmentation surgery. Methods A group of 25 female patients (50 breasts) underwent a surgical protocol for primary pre-pectoral implant breast augmentation with a laterally displaced sub-mammary incision. This group was compared with a similar group of 25 patients (50 breasts) who underwent breast augmentation through a conventional sub-mammary central approach. Sensitivity test was performed in both groups using Semmes-Weins...

Journal of the American College of Surgeons

Intraoperative Indocyanine Green During Cholecystectomy

The SAGES Manual of Biliary Surgery, 2019

The introduction of laparoscopic techniques has revolutionized the approach to cholecystectomy. A... more The introduction of laparoscopic techniques has revolutionized the approach to cholecystectomy. Among the clear advantages of this approach are the quicker recovery time and overall decreased morbidity. However, concerns still remain on the higher likelihood of extrahepatic bile duct injuries. Among the different reasons to explain the reason for bile duct injury during laparoscopic cholecystectomy, misinterpretation of the visualized structures remains the most common. Several techniques to improve intraoperative identification of the biliary anatomy have been described. Intraoperative cholangiography is currently the most commonly utilized technique. However, this technique has only been shown to aid in the earlier identification of an injury and not in the prevention of it. Endoscopic ultrasound is the other common technique utilized, but this technique requires a significant learning curve and could be misinterpreted. Near-infrared fluorescent cholangiography (NIRFC) has been described as an effective technique to improve visualization of the extrahepatic biliary anatomy. This technique seems to be effective, easy to learn, cheap, and reproducible. In this chapter we describe the details of this technique and the necessary intraoperative steps to take best advantage of it, based on the current available literature and personal experience.

Supplemental material, Appendix1 for Smartphone Application as an Education Platform in Hepato-Pa... more Supplemental material, Appendix1 for Smartphone Application as an Education Platform in Hepato-Pancreato-Biliary Surgery by Mayank Roy, Fernando Dip, Armando Rosales, Matthew Roche and Robert R. Hutchins in Surgical Innovation

Fluorescence imaging of the biliary tree with indocyanine green

Fluorescence imaging of the biliary tree with indocyanine green (ICG) during gallbladder surgery ... more Fluorescence imaging of the biliary tree with indocyanine green (ICG) during gallbladder surgery is slowly becoming a routine practice amongst surgeons around the world. Some of the unique advantages offered by near-infrared fluorescent (NIFR) cholangiography have made it a valuable tool for general surgeons. Low cost and the ability to operate in real time with NIFR cholangiography give this technique an edge over intraoperative cholangiography. The indications for its use continue to increase, though the appropriate dose and timing of injection of ICG continue to be debated and researched amongst clinicians. However, multiple studies, including a randomized control trial, have demonstrated improved biliary imaging with a potential to reduce bile duct injury with the technique.

part of the material is concerned, specifi cally the rights of translation, reprinting, reuse of ... more part of the material is concerned, specifi cally the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfi lms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specifi c statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use.

Midgut volvulus as initial presentation of pneumatosis cystoides intestinalis

ANZ Journal of Surgery, 2015

Pneumatosis cystoides intestinalis (PCI) is a rare disease with unknown aetiology. It is characte... more Pneumatosis cystoides intestinalis (PCI) is a rare disease with unknown aetiology. It is characterized by the presence of gas-filled cysts within the submucosa or subserosa of the intestine; however, it can be located in any part of the intestinal tract. The pathogenesis, although unknown, seems to be related to the mucosal breakdown and bacterial fermentation. PCI is associated with a variety of diseases in which there is loss of bowel mucosal integrity and/or increased intraluminal pressure. PCI is usually incidentally discovered during diagnostic modalities being carried out for other reasons. In approximately 16% of cases, PCI presents as intestinal obstruction or perforation. Patients commonly present with non-specific gastrointestinal symptoms such as intermittent abdominal pain, nausea, and in cases with colonic involvement, diarrhoea, mucus discharge, rectal bleeding and constipation. Although previously PCI was thought to occur more frequently in the small intestine, more recent studies have shown that PCI appears more frequently in the colon (61.8%), followed by the small intestine (15.4%). A 72-year-old woman presented to the emergency department with a 3-week history of severe back pain with radiation to the abdomen and now recent onset of vomiting. On examination, the vital signs were normal and the abdomen was soft with only minimal tenderness without any peritoneal signs. Laboratory values were also within normal limits. An initial computed tomography (CT) scan without contrast was read as free intra-abdominal air under the right hemidiaphragm (Fig. 1). Because of the overall paucity of clinical signs, a CT with contrast was obtained. The CT scan with oral contrast revealed a large duodenum diverticulum in the right upper quadrant and suggested a possible internal hernia; small pockets of free air were again visualized (Fig. 2). At this point, the patient was taken to the operating room for diagnostic laparoscopy. During laparoscopic exploration, at a distance of about 40 cm from the ligament of Treitz, the small bowel was twisting on itself going under the superior mesenteric artery. The internal hernia was reduced by gentle traction. Once this was accomplished, it became evident that a segment of bowel that was folding on itself contained multiple diverticula. There was no evidence of inflammatory changes, but there appeared to be air under the layer of visceral peritoneum. Since those diverticula had functioned as a lead point for the torsion, the segment of bowel was resected (35 cm) (Fig. 3) with a linear stapler. A standard side-to-side functional end-to-end anastomosis was performed. She was discharged home on postoperative day 4 tolerating regular diet. The pathology report revealed the following: small bowel segment with diverticular disease and serosal adhesions. Histological changes were consistent with arteriovascular malformation and severe atherosclerosis. Seven reactive lymph nodes were negative for neoplasm. In this unusual case report, the clinical presentation was of a volvulus around the superior mesenteric artery, likely secondary to the bulky PCI in the jejunum. To our knowledge, this is the first description of such a presentation of PCI. This underlies the importance of a complete clinical evaluation that does not only take into account the radiological findings. The initial CT scan in our case

Randomized Trial of Near-infrared Incisionless Fluorescent Cholangiography

Annals of Surgery, 2019

Background: Incisionless near-infrared fluorescent cholangiography (NIFC) is emerging as a promis... more Background: Incisionless near-infrared fluorescent cholangiography (NIFC) is emerging as a promising tool to enhance the visualization of extrahepatic biliary structures during laparoscopic cholecystectomies. Methods: We conducted a single-blind, randomized, 2-arm trial comparing the efficacy of NIFC (n = 321) versus white light (WL) alone (n = 318) during laparoscopic cholecystectomy. Using the KARL STORZ Image1 S imaging system with OPAL1 technology for NIR/ICG imaging, we evaluated the detection rate for 7 biliary structures—cystic duct (CD), right hepatic duct (RHD), common hepatic duct, common bile duct, cystic common bile duct junction, cystic gallbladder junction (CGJ), and accessory ducts —before and after surgical dissection. Secondary calculations included multivariable analysis for predictors of structure visualization and comparing intergroup biliary duct injury rates. Results: Predissection detection rates were significantly superior in the NIFC group for all 7 biliary ...

Fluorescent View of Safety During Laparoscopic Cholecystectomy

Journal of the American College of Surgeons, 2016

Journal of the American College of Surgeons, 2016

Identification of parathyroid glands may be challenging during thyroid and parathyroid surgery. A... more Identification of parathyroid glands may be challenging during thyroid and parathyroid surgery. Accidental resection of the glands may increase the morbidity of the surgery. The aim of this study was to evaluate accuracy in identification of autofluorescent parathyroid glands with the use of near infrared light in real time. Patients undergoing thyroid and parathyroid surgery between June and August 2015 were included in the study. During the procedure, the surgical field was exposed to near infrared laser light in order to analyze the intensity of the fluorescence of different tissues (parathyroid glands, thyroid glands, and background). Surgical images were recorded and analyzed. Twenty-eight patients were included in the study. Nineteen patients were women and 9 were men. Seven patients had primary hyperparathyroidism, 4 had hyperthyroidism, 3 had goiters, and 11 had thyroid cancer. Three patients had mixed pathologies, including 2 patients with thyroid cancer and primary hyperpa...

Determination in the optimal time of administering intravenous indocyanine green in fluorescent cholangiography

Journal of the American College of Surgeons, 2015

VITOM II: A prototype for fluorescent image guided surgery implementation in open surgery

Journal of the American College of Surgeons, 2015

Neck Cancer: Imaging Techniques and Progress on the Operative Approach

Technological Advances in Surgery, Trauma and Critical Care, 2015

Treatment of head and neck cancer has undergone considerable advances and requires multidisciplin... more Treatment of head and neck cancer has undergone considerable advances and requires multidisciplinary approach that embraces surgery, radiotherapy, and chemotherapy. Nevertheless, the 5-year survival rate is only 50 % after recurrence, lymph node involvement, and metastatic disease. We discuss head and neck cancer genetics and molecular progress, advances in diagnostics, and an emphasis is placed on treatment such as surgical procedures and applicable technologies.

Obesity Surgery, 2015

Background Fluorescence cholangiography represents an incisionless technique that can be applied ... more Background Fluorescence cholangiography represents an incisionless technique that can be applied during laparoscopic cholecystectomy to visualize bile ducts. Our objective was to evaluate and detect variances of fluorescence imaging in obese and non-obese patients. Methods Prospective patients were selected for laparoscopic cholecystectomies. Subjects were divided into groups based on their body mass index. Fluorescence imaging was applied preceding any dissection of extrahepatic ducts and again after dissection. Positive and negative identifications of biliary ducts were recorded. Results Seventy-one patients participated, with 53.5 % classified as obese. The cystic, hepatic, common bile duct, and accessory ducts were identified as follows: 100, 70.4, 87.3, and 7.0 % of patients, respectively. No differences in hepatic duct, common bile duct, and accessory duct visualization were detected in the obese and non-obese groups (p value 0.09, 0.16, and 0.66, respectively). Conclusions Fluorescent cholangiography is a useful technique in the obese and non-obese population. Obesity does not affect fluorescence visualization of bile ducts.

Past, Present, and Future of Fluorescence

Fluorescence Imaging for Surgeons, 2015

It is important to define fluorescence. There are several ways to describe this term: (1) the emi... more It is important to define fluorescence. There are several ways to describe this term: (1) the emission of electromagnetic radiation, especially of visible light, stimulated in a substance by the absorption of incident radiation and persisting only as long as the stimulating radiation is continued. (2) Emitting light during exposure to radiation from an external source. (3) Luminescence that is caused by the absorption of radiation at one wavelength followed by nearly immediate reradiation usually at a different wavelength and that ceases almost at once when the incident radiation stops. The common denominators for this term are a source of radiation, the absorption of this radiation, and the emission of a modified radiation that ends immediately as the source stops emitting radiation. Chemically speaking, fluorescence is brought about by absorption of photons in the singlet ground state promoted to a singlet excited state. The spin of the electron is still paired with the ground state electron. As the excited molecule returns to ground state, it involves the emission of a photon of lower energy, which corresponds to a longer wavelength, than the absorbed photon and therefore lower energy, than the absorbed radiation.

Ureter Identification Using Methylene Blue and Fluorescein

Fluorescence Imaging for Surgeons, 2015

The use of a multimodal optical system that expands the surgeon’s light spectrum of view can impr... more The use of a multimodal optical system that expands the surgeon’s light spectrum of view can improve surgical performance making structures clearly visible during laparoscopic and open surgery. This allows for shorter procedural duration and improved prevention and incidence of ureteral injury associated with complex pelvic surgery. Optical imaging using invisible NIR fluorescent light has several advantages over currently available intraoperative techniques. First, visualization of the ureters does not require ionizing radiation, and uses only safe wavelengths of light for ample excitation. Secondly, because fluorescence emission is invisible to the human eye, the surgical field is not stained or changed in any way. The blue dyes that are currently used stain the surgical field and have relatively poor contrast. Thirdly, imaging can be performed in real-time (up to 15 frames per second) with the merged image from the color video and NIR fluorescent cameras providing anatomical landmarks that are easily identifiable. More work is needed to identify the optimal contrast agent and light wavelength with which it is most optimally visualized. Overall, this field of knowledge is of great interest and reports a great growing potential.

Surgical Endoscopy, 2015

Background Incisional hernias remain a significant complication of abdominal surgeries. Primary c... more Background Incisional hernias remain a significant complication of abdominal surgeries. Primary closure of the hernia defect has been suggested to improve long-term abdominal wall function. However, this can be technically challenging and time consuming. This study describes laparoscopic use of non-absorbable barbed sutures in primary closure of hernia defects in addition to intraperitoneal mesh. Methods Patients who underwent laparoscopic primary ventral hernia repair with mesh were prospectively reviewed. Two groups were defined: Operations performed with barbed sutures for primary closure in addition to mesh and operations with only mesh without defect repair. The surgical technique involved running the hernia defect with a 2-polypropylene non-absorbable unidirectional barbed suture and subsequently fixing the mesh intraperitoneally with tacks. In both groups, a single transfascial centering suture was also utilized. Results Twenty-eight cases with barbed suture and mesh reinforcement and 29 cases with mesh-only were identified. The average dimensions of the ventral hernia defects were 57.8 (6-187) and 44.6 cm 2 (9-156) in the barbed suture with mesh and mesh-only group, respectively, p = 0.23. Median operating time was 78 min (range 35-187 min) in the barbed suture with mesh group versus 62 min (34-155 min) in the mesh-only group, p = 0.44. The median suturing time of closing the ventral hernia defect was 16 min (11-24 min). There were no differences in the pain scores. Mean follow-up for both groups was 8.2 ± 3.6 months (1-17 months) with one hernia recurrence in the mesh-only group, p = 0.41. Conclusions The barbed suture closure system could be used for rapid and effective primary defect closure in laparoscopic ventral hernia repair in addition to intraperitoneal mesh placement. No significant difference in operating time was detected when compared to the mesh-only approach. Further evidence to support these findings and longer follow-up periods is warranted to evaluate shortand long-term complications.

Impact of controlled intraabdominal pressure on the optic nerve sheath diameter during laparoscopic procedures

Surgical Endoscopy, 2015

Acute elevations of intraabdominal pressure (IAP) are seen in many clinical scenarios with a cons... more Acute elevations of intraabdominal pressure (IAP) are seen in many clinical scenarios with a consequent elevation in intracranial pressure (ICP). With the optic nerve sheath (ONS) being a part of the dura mater and the optic nerve surrounded by cerebral spinal fluid, a change in pressure within the subarachnoid space would be detected by ultrasonography, and invasive methods could be avoided. The study objective was to evaluate ultrasonographic modifications observed on the optic nerve sheath diameter during acute elevations of IAP in patients undergoing laparoscopic procedures. We prospectively collected data from patients who underwent laparoscopic procedures between July and August 2013. The optic nerve sheath diameter was measured sagittally with a 12-MHz transducer. The measurements were obtained at baseline, 15 and 30 min, and at the end of surgery. There were 16 females (36.4 %) and 28 males (63.6 %), with a mean age of 44.22 ± 10.44 years (range 23-66) and body mass index of 29.45 ± 6.53 kg/m(2) (range 21-39). The mean optic nerve sheath diameter was 4.8 ± 1.0 mm at baseline, 5.5 ± 1.1 mm at 15 min, 5.9 ± 1.0 mm at 30 min, and 5.1 ± 1.2 mm after deflation of pneumoperitoneum. The diameter increased significantly at 15 min by a median of 0.6 mm (interquartile range 0.3, 0.8; p < 0.0001) and at 30 min by a median of 1.0 mm (interquartile range 0.7, 1.4; p < 0.0001), returning close to baseline after surgery. The acute elevation in IAP during laparoscopy significantly increased the optic nerve sheath diameter. The changes in the ONSD reflect a temporary and reversible increase in the ICP due to the acute elevation of IAP.

The use of mechanical stapling devices in laparoscopic appendectomies has become a common practic... more The use of mechanical stapling devices in laparoscopic appendectomies has become a common practice. Occasionally, the retained staples have been described to cause adhesions that might result in bowel obstruction. Early bowel obstruction after routine abdominal surgery should be closely investigated and might warrant early re-exploration. We present a rare case of small bowel obstruction caused by a staple line adhesive band one week after appendectomy. A 46-year-old female underwent laparoscopic appendectomy for uncomplicated appendicitis. A linear endoscopic stapling device was utilized during the procedure. The patient was discharged without complication. One week later, the patient presented to the emergency room for abdominal pain and she was discharged after adequate pain control. Several hours later she returned with similar symptoms, and she was diagnosed with distal small bowel obstruction by computed tomography scan. During the diagnostic laparoscopy there was an internal hernia through a defect created by the appendiceal staple line and the adjacent small bowel mesentery. After reduction of the hernia, the small bowel venous drainage improved, and no intestinal resection was necessary. The offending staple was removed and the staple line covered with omentum. The patient had complete resolution of symptoms and she was discharged the following day. No perioperative complications occurred. Mechanical staplers are routinely used in laparoscopic appendectomy. The staple line should be inspected at the end of the procedure to confirm the absence of free, unformed staples that can generate adhesions and postoperative complications.

Cost analysis and effectiveness comparing the routine use of intraoperative fluorescent cholangiography with fluoroscopic cholangiogram in patients undergoing laparoscopic cholecystectomy

Surgical Endoscopy, 2014

Sensory Evaluation of the Nipple-Areolar Complex Following Primary Breast Augmentation: A Comparison of Incision Approaches

Aesthetic Surgery Journal

Background The central inframammary incisional approach for breast augmentation surgery disrupts ... more Background The central inframammary incisional approach for breast augmentation surgery disrupts the fifth anterior intercostal (AIC) nerve-artery-vein-plexus. Objectives The authors hypothesized that preservation of the fifth AIC neurovascular pedicle might completely preserve nipple areola complex (NAC) sensitivity after implant breast augmentation. The aim of the study was to analyze if the use of a laterally displaced incision is related with better sensitivity results than the conventional median sub-mammary incision in females who underwent primary breast augmentation surgery. Methods A group of 25 female patients (50 breasts) underwent a surgical protocol for primary pre-pectoral implant breast augmentation with a laterally displaced sub-mammary incision. This group was compared with a similar group of 25 patients (50 breasts) who underwent breast augmentation through a conventional sub-mammary central approach. Sensitivity test was performed in both groups using Semmes-Weins...

Journal of the American College of Surgeons

Intraoperative Indocyanine Green During Cholecystectomy

The SAGES Manual of Biliary Surgery, 2019

The introduction of laparoscopic techniques has revolutionized the approach to cholecystectomy. A... more The introduction of laparoscopic techniques has revolutionized the approach to cholecystectomy. Among the clear advantages of this approach are the quicker recovery time and overall decreased morbidity. However, concerns still remain on the higher likelihood of extrahepatic bile duct injuries. Among the different reasons to explain the reason for bile duct injury during laparoscopic cholecystectomy, misinterpretation of the visualized structures remains the most common. Several techniques to improve intraoperative identification of the biliary anatomy have been described. Intraoperative cholangiography is currently the most commonly utilized technique. However, this technique has only been shown to aid in the earlier identification of an injury and not in the prevention of it. Endoscopic ultrasound is the other common technique utilized, but this technique requires a significant learning curve and could be misinterpreted. Near-infrared fluorescent cholangiography (NIRFC) has been described as an effective technique to improve visualization of the extrahepatic biliary anatomy. This technique seems to be effective, easy to learn, cheap, and reproducible. In this chapter we describe the details of this technique and the necessary intraoperative steps to take best advantage of it, based on the current available literature and personal experience.

Supplemental material, Appendix1 for Smartphone Application as an Education Platform in Hepato-Pa... more Supplemental material, Appendix1 for Smartphone Application as an Education Platform in Hepato-Pancreato-Biliary Surgery by Mayank Roy, Fernando Dip, Armando Rosales, Matthew Roche and Robert R. Hutchins in Surgical Innovation

Fluorescence imaging of the biliary tree with indocyanine green

Fluorescence imaging of the biliary tree with indocyanine green (ICG) during gallbladder surgery ... more Fluorescence imaging of the biliary tree with indocyanine green (ICG) during gallbladder surgery is slowly becoming a routine practice amongst surgeons around the world. Some of the unique advantages offered by near-infrared fluorescent (NIFR) cholangiography have made it a valuable tool for general surgeons. Low cost and the ability to operate in real time with NIFR cholangiography give this technique an edge over intraoperative cholangiography. The indications for its use continue to increase, though the appropriate dose and timing of injection of ICG continue to be debated and researched amongst clinicians. However, multiple studies, including a randomized control trial, have demonstrated improved biliary imaging with a potential to reduce bile duct injury with the technique.