Short Vessels Research Articles

Minimal Access Surgery in the Neonate

After completing this article, readers should be able to: 1. Review physiologic, anatomic, and technical issues related to minimal access surgery in the neonate. 2. Describe conditions in which minimal access surgery can be used in neonates. Historically, pediatric surgeons were slow to adapt to minimal access surgery (MAS) techniques compared with the adult surgical community. However, MAS now is widely established in infants and children. Differences in size and physiology have necessitated a number of surgical and technological modifications to apply MAS techniques to this population. This review outlines the important differences between children and adults with respect to MAS and provides examples of the use of MAS for diseases seen in infants. ### Physiologic Issues The physiologic response to pneumoperitoneum in children is more pronounced than in adults. Peritoneal insufflation with carbon dioxide has been shown to cause hypercarbia, acidemia, and decreased oxygenation in the pediatric piglet model. (1) In infants, however, there is no detrimental effect on blood pressure, heart rate, or oxygen saturation during short periods of pneumoperitoneum, and elevations in end-tidal CO2 can be counteracted readily by increasing the minute ventilation. (2) Hypercarbia-induced pneumoperitoneum in infants is associated with changes in cerebral blood flow and cardiac output. Nevertheless, laparoscopic procedures have been performed safely with proper anesthetic management in children who have even severe congenital cardiac abnormalities such as hypoplastic left heart syndrome. (3) Hypothermia also can be a concern due to rapid insufflation of unwarmed CO2 gas, mandating the moderation of flow rates. (4) ### Anatomic Issues A number of anatomic factors set children apart from adults and must be accounted for when performing laparoscopic surgery in this age group. Young children and infants have thinner abdominal walls than adults, so extreme care must be exercised when placing trocars. Due to the small size of the abdomen, the working …

The Fate of Target Visceral Vessels After Fenestrated Endovascular Aortic Repair—General Considerations and Mid-term Results

Objective To carry out a retrospective analysis of the short and mid-term target vessels (TV) patency following fenestrated endovascular aortic repair (f-EVAR) of abdominal aneurysm (AAA). Patients and methods Seventeen f-EVAR patients were analysed. The Zenith (Cook) fenestrated graft was used in all cases. Bare renal stents were used where good apposition existed between the stent graft and the aortic wall, and covered stents were chosen when this apposition appeared deficient. Results A total of 35 TV were treated: twenty with small fenestration and 15 with a scallop. Procedural technical success was achieved in 16 out of 17 patients. All TV were perfused at the completion angiography. Access to TV through small fenestrations was achieved in 18 out of 20 vessels. After a mean follow-up of 20.5 months no type I endoleaks were detected. No late complications were observed in any of the stented TV. One patient with perioperative bilateral renal artery occlusion remains on haemodialysis. One non-target renal artery, opposite a scallop was unintentionally covered. One kidney, initially perfused via a un-stented scallop fenestration, was atrophied 14 months post surgery. One patient died from heart failure. Conclusions f-EVAR is a valid and safe treatment option. Our series and the world literature demonstrates a >90% TV preservation rate. Long-term intensive surveillance is required.

Guideline for the Surgical Diagnosis and Treatment of Nonpalpable Testis Based on Experiences with Laparoscopic Procedure

Purpose: We assessed our laparoscopic experiences for the children with nonpalpable testis to evaluated the advantages of performing laparoscopy and we suggest a surgical management guideline for them. Materials and Methods: We retrospectively reviewed the medical records of a total of 83 children(97 testes) who underwent diagnostic laparoscopy for nonpalpable testes. We analyzed the surgical decisions and outcomes according to the laparoscopic findings. Results: On the laparoscopic examination, 48(49.5%) testes were located in the abdominal cavity. We subsequently performed inguinal orchiopexy (28), laparoscopic orchiopexy(8), Fowler-Stephens orchiopexy(10, one or two stage), or orchiectomy(2). The other 40(41.2%) were suspected to be testicular nubbin, and we managed this by excision of the testicular nubbin by the inguinal(29) or scrotal(10) approach, except for one viable testis in the inguinal canal. When blind-ending vessels were observed, we stopped the procedure under the diagnosis of vanishing testis in 9 cases(9.3%). The testicular survival rates were 92.6%(25/27) for inguinal orchiopexy, 100%(8/8) for laparoscopic orchiopexy and 60%(6/10) for Fowler-Stephen orchiopexy. Conclusions: We preferred laparoscopic orchiopexy for treating intraabdominal testis when the location was 2.5cm from the internal ring. When the testicular location was closer to the internal ring, we recommend inguinal orchiopexy as a viable option. In cases with high riding testis or very short internal spermatic vessels, we recommend Fowler-Stephens orchiopexy. For the suspected testicular nubbin, we preferred trans-scrotal excision when the nubbin was identified in the scrotum. Otherwise, we recommend inguinal exploration.

Living donor liver transplantation for biliary atresia complicated by situs inversus: Technical highlights

Living-donor liver transplantation (LDLT) has become an established technique to treat children with end-stage liver disease. Biliary atresia (BA), one of the most common indications for liver transplantation in children, can be associated with situs inversus (SI). In the past, the presence of SI has been considered to be an absolute contraindication for liver transplantation because of the technical difficulties. Recently, some reports of successful diseased-donor liver transplantation in patients with BA complicated by SI have been published; however, few reports of that with LDLT exist. The technical difficulties involved with LDLT for such cases have not been described. Herein, we present 4 successful cases of LDLT for BA with SI. Complex anomalies associated with SI, such as a hepatic artery arising from the supraceliac aorta, a preduodenal portal vein, and absence of the retrohepatic inferior vena cava, increase the technical difficulties involved with the operation. Additional caution is required in LDLT because a living-donor graft has short vessels and the availability of vascular grafts from the donor is limited. In conclusion, LDLT for BA complicated by SI can be managed successfully with technical modifications and scrupulous attention. This series represents the largest reported group of patients with BA complicated by SI who underwent a successful LDLT procedure.

Stress Concentration Effects in Short Cylindrical Vessels With Holes Subjected to Tension: A Complete Account

Whenever regular geometric discontinuities are present the so called stress concentration factors concept is widely used in both analysis and design of loaded components especially when subjected to fatigue, frequently the working condition of vessels. However, recent observations suggest that the influence of member length on the magnitude of the stated factors was not considered in previous analyses. In this work, this observation was studied in the context of cylindrical vessels and it was found that in this case, as well, length could be a critical factor when computing stresses developed as a result of externally applied loads. Accordingly, the values of the finite element calculated theoretical stress concentration factors are computed, for the case of short circular cylinders with circular holes subjected to axial tension, in the context of elastic shell theory, and are presented in a fashion similar to existing published results. It is shown that significantly larger stress concentrations appear for shorter members. The transition length concept defining the threshold between long cylinders and short cylinders is discussed in the context of this study and reported as well.

Laparoscopic Fowler-Stephens procedure is contraindicated for intraabdominal testicular major duct anomalies.

The laparoscopic one- and two-stage Fowler-Stephens procedure has gained large popularity in the treatment of the child with a high intraabdominal testis. It is largely debated which technique (e.g., testicular autotransplant or Fowler-Stephens procedure) offers the best results for high intraabdominal testes. We describe a case of a 3-year-old boy for whom previous bilateral inguinal exploration results were negative for testes or testicular remnants. The diagnostic laparoscopy showed two iliac intraabdominal testes with short spermatic vessels, closed inguinal rings, and complete dissociation of didime-epididime. A left open orchidopexy was perfomed, and testicular autotransplant was proposed for the right testes located 4 cm from the internal inguinal ring. Long-term follow-up evaluation (1.8 years) of the left testis showed it in the scrotum with good testicular size (1.5 cm). We believe that there are two main reasons to contraindicate the Fowler-Stephens technique: associated malformation that does not permit the development of the collateral blood flow via the vasal artery necessary for a viable testis, and previous surgery that represents a risk factor for testicular atrophy. The laparoscopic anatomic classification for the intraabdominal testis is reliable and can disclose the most suitable surgical technique. Laparoscopy is a valuable tool in the diagnosis and treatment of the nonpalpable testicle.

Novel Magnified Colonoscopic Findings of Microvascular Architecture in Colorectal Tumors

Background: Tumor vessel density is a predictive parameter for metastatic propagation, overall survival, and/or relapse-free survival for patients with colorectal carcinoma (Ishikawa et al., 1999). However, colonoscopic findings of the microvascular architecture in colorectal tumors have not been reported. We investigated the colonoscopic microvascular architecture in colorectal tumors. Methods: Sixty colorectal tumors were studied. Those tumors were finally resected endoscopically and/or surgically. Each patient received a colonoscopic examination for colorectal cancer screening using a zoom type magnifying colonoscope EC-450ZH (Fujinon, Japan), with attention given to microvascular findings. If the lesion was detectable by non-magnified observation, it was subsequently magnified up to 100 times using a zoom system. Immediately following the examination, the magnified findings were recorded. The colorectal tumors were divided into 4 major types histologically; A type, which consisted of adenomas (15 cases); B type, which consisted of sm-minimum invasive cancers (15 cases) with a submucosal invasion depth of 0.5 mm or less; C type, which consisted of sm-massive invasive cancers (11 cases) with a submucosal invasion depth greater than 0.5 mm and negative vessel invasion; and D type, which consisted of sm-massive invasive cancers (19 cases) with a submucosal invasion depth greater than 0.5mm and positive vessel invasion. Results: A type tumors showed thin micro-vessels with regular size, shape, and distribution. In contrast, thicker micro-vessels with irregular shape and distribution(short irregular tumor vessels) was a primary characteristic of submucosal invasive cancer (Types B, C, D). In addition, elongated irregular tumor vessels(long irregular tumor vessels) were seen in sm-massive cancer with vessel invasion (Type D). As for differential diagnosis between sm-massive cancer with and without vessel invasion, sensitivity, specificity, positive predictive value, and negative predictive value of the magnified findings for long irregular tumor vessels were 86%, 100%, 100%, and 73% respectively. Further, sm cancers with lymph node metastasis (3 cases) were only seen in Type D. Conclusion: Magnified colonoscopic observation of micro-vessels may be helpful for diagnosing colorectal tumors, especially sm-massive cancers in which show greater degrees of malignancy.

One-stage Fowler-Stephens orchidopexy for impalpable undescended testis

The Fowler-Stephens orchidopexy (FSO) is a well-described treatment for high maldescended testes where the limiting factor for successful placement in the scrotum is short testicular vessels. The operation involves division of these vessels. The testicular blood supply is then dependent on collaterals from the vasal artery. To assess the long-term outcome of patients who underwent this procedure in our institution. The medical records of 20 patients who underwent 22 FSO from 1978 to 1999 by one urologist (HB) were reviewed. Outcome was assessed in terms of testicular position and size. Age at operation ranged from 2 to 14 years (mean 5.8 years). All patients had a one-stage FSO and in two of them the procedure was bilateral. In five patients, FSO was preceded by a diagnostic laparoscopy. Mean follow up was 22 months (range 0-121 months). Overall, results were considered good in 18 of 22 testes (82%). Our results for the one-stage FSO are comparable with other procedures for the management of high maldescended testis.

Management of renal allografts with multiple renal arteries resulting from laparoscopic living donor nephrectomy.

Laparoscopic living donor nephrectomy (LLDN) has become an accepted procedure in many transplant centers. The placement of laparoscopic vascular staples can result in multiple short, small-caliber renal arteries that the recipient surgeon must deal with to restore perfusion to all parts of the kidney. The incidence of multiple renal arteries resulting from LLDN, surgical management of multiple renal arteries, and the short- and long-term graft functions were studied in 73 consecutive kidney recipients at a single center. Various techniques used for reconstruction are described, including the use of recipient internal iliac artery for the extension and reconstruction of small-caliber, short renal vessels. Single-artery allografts were compared with those with multiple arteries, with length of renal artery, warm ischemia time, hospital length of stay, operating time, creatinine levels, and 1 yr survival rates not found to be significantly different. The presence of multiple renal arteries should not exclude the possibility of using the left kidney for LLDN.

Could the use of interposition grafts for arterial reconstruction be avoided by more caudate graft placement in living donor liver transplantation?

One of the major challenges in living donor liver transplantation (LDLT) is short and small vessels (particularly the hepatic artery), particularly in segmental liver grafts from living donors. In the present study we report an alternative surgical technique that avoids interpositional vessel grafts or tension on the connection by anastomizing the allograft hepatic vein to the recipient inferior vena cava in a more caudate location. From March 2000 to January 2003, 28 patients (11 women/17 men) underwent 28 LDLT. Until June 2001, the preferred technique for hepatic vein anastomosis was end-to-end anastomosis between the allograft hepatic vein and the recipient hepatic vein (HV-HV) (n = 10). Thereafter an end-to-side anastomosis was performed between allograft hepatic vein and recipient inferior vena cava (HV-IVC) (n = 18). The level of venotomy on the recipient vena cava was decided according to the pre-anastomotic placement of the allograft in the recipient hepatectomy site with sufficient width to have an hepatic artery anastomosis without tension or need for an interposition graft during hepatic artery and portal vein anastomoses. Except the right lobe allograft with anterior and posterior portal branches, all portal and hepatic artery anastomoses were constructed without an interposition graft or tension in the HV-IVC group. Only one hepatic artery thrombosis developed in the HV-IVC group. As a result, this technique may avoid both hepatic artery thrombosis and the use of interposition grafts in living donor liver transplantation.

Posterior approach for simultaneous access to the popliteal and anterior tibial arteries: applications to distal arterial bypass.

Arterial surgery to salvage the lower limb tends to make use of the great saphenous vein, harvested with the subject in the supine position. If this is not possible the small saphenous vein is used, harvested with the subject in the prone position, however this requires a perioperative modification of the procedure. A bypass between the popliteal and anterior tibial arteries can be performed using either a lateral or a medial and lateral approach with the patient supine. In the event of trophic disorders of the lateral compartment of the leg, these approaches are not applicable. In such cases we propose a single posterior approach. The single posterior approach was used on 10 lower limbs from 5 cadavers in the prone position. Approach to the lower part of the popliteal artery was undertaken posteriorly between the two heads of gastrocnemius. The small saphenous vein was entirely dissected 10 cm above the lateral malleolus, the Achilles tendon and short fibular vessels were retracted medially to expose the interossous fascia, which was divided over 10 cm. Medial rotation of the limb by 30 degrees exposed the anterior tibial artery. For 3 of the lower limbs an 8 cm fibular resection was necessary, whereas on the remaining 7 medial rotation enabled excellent exposure of the anterior tibial artery. The single posterior approach to the anterior tibial artery can be applied in cases requiring distal bypass, using the small saphenous vein, between the inferior part of the popliteal artery and the anterior tibial artery.

Appendix TOAST Abstraction Manual TOAST Medical Record Abstraction Manual

Appendix TOAST Abstraction Manual TOAST Medical Record Abstraction Manual

Suckling-Induced Change in Oxytocin but not in α-Msh Concentrations of the Median Eminence, The Neural-, Intermediate- and Anterior Lobes of the Pituitary Gland

Previous reports have implicated that pituitary-derived prolactin (PRL) is secreted from two distinct zones of mammotropes within the anterior lobe (AL). The inner zone (AL-IZ), located adjacent to the neuro-intermediate lobe (NIL), is supposed to be involved in the rapid and massive discharge of PRL from the pituitary gland due to suckling stimulus. Whereas the outer-zone (AL-OZ) gives the basal secretion and it does not play a role in the acute secretory response during nursing. Anatomically, the AL-IZ has an intimate contact with the NIL because the blood passing through the short portal vessels (SPV) bathes it first. Based on this fact it would be hypothesized that locally released and/or produced compounds, like OXY and a-MSH, can be delivered to the AL-IZ. In conjunction, OXY and a-MSH have already been implicated to play a role in the regulation of PRL release during suckling. Therefore, the purpose of this study was to examine the possible local transportation of these hormones into the median eminence and various regions of the pituitary gland of lactating rats. We have measured the concentrations of OXY and α-MSH from tissue samples of nonsuckled (NS) and 10 or 30 min after suckling (S) was initiated using specific RIAs. It has been shown that there are no changes in the concentration of OXY and α-MSH in the AL-IZ and AL-OZ due to suckling stimulus. In contrast, our data provide compelling evidence that OXY is transported into the IL, which can be further increased by suckling stimulus. These data suggest that blood transfusing NL passes through the IL before it is drained into the cavernous sinus, which opens the road for OXY into the general circulation. In addition, our data have unequivocally shown a lack of local delivery of either α MSH or OXY into the AL that raises serious doubt about their possible role in PRL secretion during suckling stimulus.

Structural specializations of the eye in the vizcacha (Lagostomus maximus maximus).

Vizcachas (Lagostomus maximus maximus, Chinchillidae) are nocturnal rodents living in burrows in many regions of Argentina, Bolivia, and Chile. We have studied the eye of the vizcacha using several light and electron microscopic procedures, with the purpose of understanding the role of vision in the behavior of this species. Our observations demonstrated an avascular, rod-rich retina, with a specialized region spanning through most of the equator of the eye. In this central band, all neural retinal layers exhibited a high cell density, whereas the photoreceptor layer was characterized by the presence of very long rods. In addition, the central region was associated with a distinct pigmentation pattern, including scarce granulation of the pigment epithelium, low pigmentation of the choroid, and the selective attachment of suprachoroidal cells to the inner scleral surface. These central modifications probably form the structural basis of a reflecting tapetum. The eye of the vizcacha received both long and short ciliary vessels, and a specialized cilio-sclero-choroidal vascular network appeared at the equatorial region. Our findings suggest that the equatorial region of the eye of the vizcacha could be a highly sensitive light detector related to foraging behaviors during crepuscular or nocturnal hours.

Vascular reconstruction using interposed small vessels.

This study presents the relationship between the patency of short-vessel graft bypasses and their diameter/length. The authors performed interposed graft bypass operations using small vessels for four patients with moyamoya disease, six patients with cerebral thrombosis, and one patient with aortitis syndrome. The donor artery was the superficial temporal artery (10 patients) or the occipital artery (1 patient), and the recipient artery was the cortical branch of the middle cerebral artery (8 patients) or the cortical branch of the anterior cerebral artery (3 patients). The interposed graft used between these donor and recipient vessels was the superficial temporal vein (seven patients), the superficial temporal artery (three patients), or the epigastric artery (one patient). Good patency of the graft was confirmed for 7 of these 11 patients. Regarding the relationship between the diameter/length and the patency, we found that long-term patency could not be expected when the discriminant function of y = (15.39 x diameter) - (0.35 x length) - 14.37 was below zero. Short-vessel graft bypass is a practical option for cerebral revascularization surgery when short large vessels are used.

Magnetic sensor data acquisition for three-dimensional ultrasound of the orbit.

Three-dimensional (3D) B-mode ultrasound imaging is now possible using a magnetic sensor data acquisition system to localise data points, allowing free-hand scanning. We report the first use of this freehand scanning system for insonation of the orbit. We insonated 10 orbits in 5 volunteers (all men; mean age 37 years) with an Acuson 128XP ultrasound system and a 7.5 MHz transducer. Power-Doppler was used to image vascular structures. Data were acquired using a new magnetic sensor system with detectors mounted on the transducer. Free-hand scanning was done using sweeping or fan-like and linear movements over 20-30 s to cover the orbit, with retrospective measurements of orbital structures. A 3D reconstruction was performed via an external workstation. All orbits were adequately imaged by one data acquisition. Selected intraorbital structures were identified and their course followed, including optic nerve and central vessels, as well as short and long ciliary vessels. The mean transverse area of the optic nerve was 5.6 +/- 1.1 mm2; the diameter of the optic nerve was 3.0 +/- 0.3 mm. The lateral rectus muscle was clearly seen, with a mean diameter of 4.9 +/- 0.3 mm, at the level of optic nerve head. Three-dimensional ultrasound of the orbit allows imaging of the location, course and relationships of intraorbital vessels, the optic nerve and the lateral rectus muscles with one data acquisition, as well as quantitative measurements not possible with 2D images alone. This method allows rapid, free-hand data acquisition, with a multitude of potential clinical applications.

Résultats de la fundoplicature par voie laparoscopique dans le traitement du reflux gastro-œsophagien. À propos de 224 cas

Study aim The aim of this paper is to evaluate prospectively immediate and 2-year results of laparoscopic fundoplicature (LF) for gastroesophageal reflux disease (GERD). Patients and methods Patients presenting GERD who had been previously submitted to a long-term medical treatment were included in this study. Preoperative workup included upper Gl tract endoscopy, esophageal manometry and 24-hour pHmetry. Standard surgical procedure incorporated a Nissen-Rossetti 360 ° fundoplicature. Short vessels division (Nissen operation) was performed in case of high strength of the wrap and a partial fundoplicature (Toupet 270 °) was performed when motility disorders of the esophagus were demonstrated by manometry. Postoperative morbidity and results were evaluated, with a clinical appreciation at 3 and 22 months, and by manometry and pHmetry at 3 months. Results Two hundred and thirty-five patients were observed, and 224 included in the study (143 men and 92 women). Nissen-Rossetti fundoplication was performed in 169 cases (80%), Nissen in 30 (14%) and Toupet in 13 (6%). In 12 cases (5%). LF was converted to an open Nissen-Rossetti procedure. There was no hospital mortality and complications were noted in three cases (1.5%): pneumonia ( n = 2) and gastroplegia ( n = 1). With a mean 22-month follow up, among the 103 patients who answered to a questionnaire, the rate of relapse of GERD was 14%, dysphagia was present in 2% and four patients had been reoperated on (one for a slipped Nissen, one for a stenosis of the esogastric junction and two incisional hernias). Conclusion On the basis of this experience, LF for GERD is a safe and efficient operation, with 86% of good results at 2 years.

Fundoplicature de Nissen avec et sans section des vaisseaux courts. Étude prospective contrôlée

Fundoplicature de Nissen avec et sans section des vaisseaux courts. Étude prospective contrôlée

Ulceration of the ileum in Crohn's disease: correlation with vascular anatomy.

BACKGROUND: Ileal ulcers in Crohn's disease tend to lie along the same side of the bowel wall as the mesenteric attachment; the mesenteric and antimesenteric borders are supplied by short...

Intramural blood vessels of the large intestine of the horse (Equus przewalskii f. caballus)

The vascular system of the large intestine of 12 horses was examined by means of vascular corrosion casts, histology and transmission electron microscopy providing the following results. The Aa. et Vv. breves et longae leave the mesenteric vessels, respectively the subserously on the teniae lying cecal vessels to reach the tela subserosa at the mesenteric margin. The short vessels enter the deeper layers of the wall instantly, whereas the Aa. et Vv. longae move towards the submucosa by penetrating the muscular layers after a variable subserous course. The tela submucosa contains an arterial and a venous vascular plexus. In broader areas of the submucosa a three-dimensional vascular network can be found. This consists of a deep and a superficial vascular plexus, which are closely interconnected. The deep plexus is applied to the inner circular muscles, whereas the superficial plexus is adjacent to the muscularis mucosae. The (deep) arterial plexus receives its afflux from the Aa. breves et longae and supplies parts of the circular muscle layer with recurrent muscle branches. The vascularisation of the mucosa also originates from the submucosal (superficial) plexus. In the basal tunica mucosa, the ascending arteries form a transversal network from which arterioles branch into periglandular capillaries around each Lieberkühn crypt. Close to the lumen, a polygonal subepithelial capillary system is formed. The capillaries turn into postcapillary venules immediately below the epithelium of the mucosal surface. Veins move vertically through the submucosa to enter the submucosal plexus after few inflowing side branches. Branches of the subserous-submucosal connections form an intermuscular plexus between the circular and longitudinal muscular layer. This plexus supplies the capillaries of the tunica muscularis. The subepithelial capillaries are predominantly lined with a fenestrated endothelium, whereas the capillaries of the pericryptal mucosa mainly show a continuous endothelial lining. The latter contain multiple vesicles, which may fuse in order to form transcytoplasmic channels. Sphincter-like muscle bundles at the transition points from capillaries to venules may provide hemodynamic regulatory structures in the submucosa of the horse. Veins with circumferential cushions of smooth muscle fibres, so-called 'throttle veins', are also found.