Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Clips”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 235 records · Page 13Linked to original sources
PubMed2002

Neuropsychological sequelae of patients treated with microsurgical clipping or endovascular embolization for anterior communicating artery aneurysm.

BACKGROUND AND PURPOSE: While microsurgical clipping has been the choice of treatment for anterior communicating artery (ACoA) aneurysm, endovascular embolization is increasingly popular for treating intracranial aneurysms. Previous studies showed that in terms of mortality (i.e., death) and morbidity (i.e., functional outcome, independent living, rebleeding) rates, the clinical outcomes of coil embolization for intracranial aneurysms are as good as or even better than those of surgical clipping. However, little is known about the impact of these treatments on the cognitive functions of those survived after the treatment. Thus, the present study is designed to examine the cognitive deficits of patients treated with either surgical clipping or coil embolization. METHOD: Eighteen patients with a ruptured ACoA aneurysm were recruited. Half of them had undergone surgical clipping and the other half had endovascular embolization. Standardized neuropsychological tests were employed to assess their memory, executive function, motor ability, language and visual perceptual abilities. RESULTS: The performance of the patients was in general poorer than that of the normal control subjects on tests of verbal memory, flexible thinking, ability to resist interference and motor control. However, in terms of severity, the patients who received surgical clipping demonstrated more severe impairment than those had endovascular embolization on these cognitive domains. In addition, while 33% of patients in the clipping group showed impairments on memory and executive function, no patient in the embolization group demonstrated these impairments. CONCLUSIONS: Patients with ACoA aneurysm demonstrated impaired verbal memory, executive function and motor abilities while their language and visual perception abilities remained relatively intact. However, when comparing the effect of treatment choice on the cognitive functions of these patients, the present results favored the coil embolization as the patients treated with coil embolization demonstrated significantly fewer severe cognitive deficits than patients who had undergone surgical clipping.

Adult↗
PubMedDate not supplied

Is intraluminal clip application an appropriate treatment for iatrogenic gastric perforation?

BACKGROUND: The standard treatment of iatrogenic perforation has been an urgent operation. Recently, endoscopic clip application was recommended particularly for iatrogenic perforations. This study was designed to investigate the usage of surgical clips for gastric perforations. METHOD: Forty male rats were allocated to four groups. Following a midline laparotomy, a 5-mm gastrotomy was made at the fundic part of the stomach and through this ostomy a pre-pyloric perforation was created in all groups. In group I, the perforation site was closed with polypropylene sutures. In group II, the perforation site was closed extraluminally by vascular surgical clips. In group III, the perforation site was closed intraluminally by the same number of clips. In group IV, control group, the perforation site was left open. The animals were sacrificed on the 4th postoperative day. The healing of the perforation site was evaluated by the bursting pressure and the hydroxyproline content of the suture line. RESULTS: Measurements revealed no differences in bursting pressure and hydroxyproline levels between the intraluminal clip application group (group III) and the group in which the perforation site was left open (group IV) (p > 0.05). Higher bursting pressures and hydroxyproline levels were observed in groups I and II compared to control group (p < 0.05). CONCLUSIONS: These results suggest that gastric perforations are not strengthened by intraluminal clip application. Further detailed clinical studies are necessary in order to conclude that intraluminal clip application is an appropriate treatment for iatrogenic perforation.

Animals↗
PubMed1994

Interrelation between renin mRNA levels, renin secretion, and blood pressure in two-kidney, one clip rats.

To examine the interrelation between renin mRNA levels, renin secretion, and blood pressure in rats, we clipped the left renal arteries of rats and measured renin mRNA levels in both kidneys, plasma renin activity, and blood pressure. One and 2 days after clipping, renin mRNA levels increased 3-fold and 4.3-fold in the stenosed kidney and were suppressed to 52% and 26% of controls in the intact kidneys; plasma renin activity increased from 8 to 16.5 and to 30.5 ng angiotensin I.h-1.mL-1 and systolic blood pressure rose from 114 to 123 and to 137 mm Hg. We found a strong correlation (P < .001) between plasma renin activity and renin mRNA levels in the clipped kidneys. We also found significant correlations (P < .05) between mRNA levels in the clipped and intact kidneys and between plasma renin activity and blood pressure for the individual animals. Treatment of normal rats with the converting enzyme inhibitor ramipril (5 mg/kg twice a day) for 2 days increased renin mRNA levels in both kidneys fourfold. In animals with unilateral clips, additional treatment with ramipril increased renin mRNA levels 6.4-fold in the stenosed and 3.3-fold in the intact kidneys. These findings suggest that endogenous angiotensin II exerts an inhibitory effect on renin mRNA expression in normal kidneys, clipped kidneys, and their contralaterals. Suppression of the renin gene in contralateral kidneys seems not to be directly mediated by the rise of plasma renin activity or by the rise of blood pressure in two-kidney, one clip rats.

Angiotensin II↗
PubMedDate not supplied

Intrarenal adenosine produces hypertension via renal nerves in the one-kidney, one clip rat.

The afferent renal nerves enhance sympathetic activity in the one-kidney, one-clip hypertensive rat. We have also found adenosine-sensitive nerve endings in the renal pelvis that, when stimulated, increase sympathetic activity producing hypertension. To determine whether adenosine, which is excreted when renal blood flow is reduced, activates the afferent renal nerves in one-kidney, one-clip hypertension, urinary adenosine concentration was lowered by infusing adenosine deaminase into the renal artery. Urinary adenosine concentration was threefold greater in one-kidney, one-clip hypertensive animals compared with normotensive controls. Intrarenal infusion of adenosine deaminase in one-kidney, one-clip rats lowered urinary adenosine to an undetectable level and attenuated the hypertension. Both plasma norepinephrine levels and the fall in mean arterial pressure after ganglionic blockade decreased during intrarenal adenosine deaminase infusion in one-kidney, one-clip animals. Renal denervation in one-kidney, one-clip animals prevented the changes in mean arterial pressure and plasma norepinephrine levels during intrarenal adenosine deaminase infusion. In contrast to findings in hypertensive animals, intrarenal infusion of adenosine deaminase produced no change in arterial pressure in normotensive controls. These data indicate that urinary adenosine concentration is enhanced in one-kidney, one-clip hypertension and suggest that when urinary adenosine concentration is lowered, sympathetic activity and hypertension became attenuated in this model if the renal nerves are intact.

Adenosine↗
PubMed1986

Selection criteria for drug-treated animals in two-kidney, one clip renal hypertension.

The two-kidney, one clip (2K1C) model of hypertension in the rat does not uniformly result in increased blood pressure. That is, the placement of a clip around one renal artery in a two-kidney rat will usually, but not always, produce hypertension. This is an important problem in studies designed to evaluate the ability of antihypertensive therapy to prevent hypertension. Therefore, an additional objective means other than blood pressure is needed to assess animals that are treated from the outset with antihypertensive therapy. The purpose of this study was to correlate the relative fresh weights of left (clipped)/right (nonclipped) kidneys (LK/RK) with tail-cuff systolic blood pressure in the 2K1C model of renal hypertension and to identify an LK/RK range that would exclude the animals least likely to become hypertensive (failures of the clipping procedure). On a scale of 0.0 to 1.0, an LK/RK ratio of 0.0 was present when the clipped kidney was completely infarcted or atrophied and a ratio of 1.0 was present when the clip did not cause sufficient renal artery stenosis to alter kidney weight. In a series of 72 untreated 2K1C male Sprague-Dawley rats examined 6 to 8 weeks after clipping, 100% of the animals with an LK/RK ratio of 0.5 to 0.8 (n = 19) and 75% with an LK/RK ratio of 0.4 to 0.9 (n = 38) had a blood pressure greater than 150 mm Hg. Less than 50% with an LK/RK ratio below 0.4 or above 0.9 (n = 34) were hypertensive.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Baroreceptor-heart rate reflex function before and after surgical reversal of two-kidney, one-clip hypertension in the rat.

Baroreflex function was studied in conscious early phase (less than 6 weeks) two-kidney, one-clip hypertensive rats before and 24 hours after surgical reversal of hypertension by removal of the constricting renal artery clip or after pharmacological reduction of blood pressure by an infusion of hydralazine or captopril. A normotensive sham-clipped group was included. Another group of two-kidney, one-clip rats was studied 3 weeks after unclipping. Baroreflex sensitivity, as assessed by the steady-state method using a graded phenylephrine infusion, mean arterial pressure, and heart rate were measured preoperatively and at 24 hours postoperatively. Two-kidney, one-clip rats were significantly hypertensive preoperatively compared with control (mean arterial pressure, 183 +/- 4 vs. 106 +/- 2 mm Hg, p less than 0.001), heart rate was similar (420 +/- 9 vs. 401 +/- 9 beats/min, p greater than 0.05), and baroreflex sensitivity was significantly reduced (0.76 +/- 0.07 vs. 1.50 +/- 0.20 msec/mm Hg; p less than 0.001). There was a minimal change in heart rate despite the fall in mean arterial pressure in all hypertensive groups, indicating resetting of the baroreflexes. At 24 hours after the operation, baroreflex sensitivity was unchanged in all groups compared with the preoperative value. By 3 weeks, baroreflex sensitivity was significantly greater than in the hypertensive two-kidney, one-clip rats before the operation and 24 hours after they were unclipped, but not compared with normotensive sham-clipped rats. Thus, although resetting occurs within 24 hours, whatever the method of blood pressure reduction, baroreflex sensitivity remains impaired at this time.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2002

Intraoperative angiography evaluation of the microsurgical clipping of unruptured cerebral aneurysms.

Intraoperative angiography evaluation of the clippings of cerebral aneurysms was investigated in a series of 38 consecutive patients with unruptured cerebral aneurysms to determine any favorable impact on the outcome. Unexpected findings including major arterial occlusion or residual aneurysm were identified. Specific variables such as the size and site of aneurysm were analyzed to determine the impact on clinical outcome and the incidence of clip modification. There were 11 large and 27 small aneurysms in this series. Mortality and permanent morbidity after microsurgical clipping were 0.0% and 2.6%, respectively. Unexpected angiographic findings necessitating clip repositioning consisted of residual aneurysm in two cases and distal branch occlusion or parent vessel stenosis in four. The need for clip modification was significantly higher for large than for small aneurysms (p = 0.007), and the rate of clip adjustment increased with increasing aneurysm size (p = 0.008). Intraoperative assessment prior to wound closure allows for the recognition and correction of defects and decreases the risk of postoperative complications. Intraoperative angiography may become important in the microsurgical clipping of unruptured cerebral aneurysms, especially large aneurysms.

Aged↗
PubMed1999

Usefulness of tissue marker clips in patients undergoing neoadjuvant chemotherapy for breast cancer.

OBJECTIVE: The purpose of this study was to evaluate the usefulness of a tissue marker clip in patients undergoing preoperative chemotherapy for breast carcinoma. MATERIALS AND METHODS: Between June 1996 and July 1998 (26 months), a tissue marker clip was placed in 29 patients with breast carcinoma who showed significant clinical response to preoperative chemotherapy. In these patients, 13 clips were placed stereotactically and 16 clips were placed using sonographic guidance. A retrospective review of these cases was made to evaluate helpfulness of the clip during preoperative needle localization. RESULTS: One patient relocated to another city, so surgical follow-up was available in 28 patients. Twenty-four of these 28 patients required preoperative wire localization and four still had a palpable tumor at the time of surgery. Preoperative wire localization would have been possible without any difficulty in eight patients (28.6%), possible but with some difficulty in six patients (21.4%), and impossible in 10 patients (35.7%) without the clip. Thus, clip placement was valuable in 16 (57.1%) of 28 patients at the time of preoperative needle localization. CONCLUSION: With the newer chemotherapeutic agents, the response of breast carcinoma to preoperative chemotherapy may be dramatic. In some patients, the tumor is no longer visible either on mammography or sonography, thus making the preoperative needle localization difficult or even impossible. By placing a radiopaque marker before the lesion becomes unidentifiable, one can confidently localize the tumor bed at surgery.

Adult↗
PubMed1982

One-clip, one-kidney hypertension in rats with hereditary hypothalamic diabetes insipidus.

An attempt was made to produce one-clip, one-kidney hypertension in the rat with diabetes insipidus (DI). Renal artery constriction in unilaterally nephrectomized DI rats (DI-clip) resulted in an increased blood pressure in all 9 rats, but this response was only transient in 3 rats. The magnitude of the hypertension was less in the DI-clip rats than in Long-Evans rats subjected to the same protocol (LE-clip). Infusion of saralasin i.v. at doses of 10 and 30 micrograms/kg . min. 4 to 6 weeks after surgery was without effect on mean arterial pressure in LE-clip and control DI rats, but substantially lowered blood pressure in the DI-clip rats (p less that 0.05 - 0.01). It is concluded that vasopressin is not essential for the production of one-clip, one kidney hypertension in the rat, and that, in the DI rat, the renin-angiotensin system is an important factor in this form of hypertension.

Angiotensin II↗
PubMed1978

Interrelationship of aneurysm clips and vascular tissue.

Various straight-jawed aneurysm clips were tested for occluding capabilities on a vascular tissue model. Occluding pressures varied markedly among the clip styles and were altered by changes in the lumen and tissue composition of the model. Mechanical characteristics are highly variable between clip styles, but fall within a narrow range for clips of a similar style. The complex interplay of the unique aspects of clip design and force generated by the spring in conjunction with tissue characteristics and precise clip placement upon the tissue are major variables in the apparent ability of a particular clip to occlude the neck of an aneurysm.

Animals↗
PubMed1994

Wrap-clipping with a Dacron mesh silastic sheet. Technical note.

A technique combining wrapping and clipping using a Silastic sheet coated with Dacron mesh is described for treatment of fusiform or broad-based cerebral aneurysms. This sheet is easily tailored to wrapping the aneurysm base while avoiding involvement of the cranial nerves or branching vessels. The sheet is semitransparent so that the caliber of the newly constructed parent artery is easily adjusted during wrap-clipping. After the aneurysm and the parent artery have been circumferentially wrapped with the sheet, aneurysm clips are applied on the sheet so that the base of the aneurysm is clipped between the two leaves of the sheet. This wrap-clipping technique avoids the risks involved in extracting the aneurysm from the parent artery. The Dacron mesh coating the outer surface and sufficient clip closing pressure are both helpful in preventing the clip blades from sliding. Similar previously reported techniques are reviewed and discussed in detail.

Humans↗
PubMed2001

Altered renal expression of aquaporin-2 water channels in rats with experimental two-kidney, one clip hypertension.

The present study was aimed at examining the regulation of aquaporin (AQP)-2 water channels in the kidney in two-kidney, one clip (2K1C) hypertension. Rats were made 2K1C hypertensive for 6 weeks, and their expression of AQP2 channel proteins was determined in the clipped and contralateral kidneys. To examine the upstream affecting AQP2 channels, adenylyl cyclase activity was also determined. Along with the hypertension, in the clipped kidney, the abundance of AQP2 proteins was significantly decreased in the cortex, outer and inner medulla, while their trafficking remained unaltered. Concomitantly with the reversal of the blood pressure at 24 hours following removal of the clip, the AQP2 abundance also returned to the control level. The arginine vasopressin-evoked generation of cAMP was decreased in the clipped kidney, which again was reversed to the control level following removal of the clip. In contrast, the expression of AQP2 channels as well as the activity of adenylyl cyclase remained unaltered in the contralateral kidney. These results indicate an altered regulation of AQP2 water channels in the clipped kidney in 2K1C hypertension.

Adenylyl Cyclases↗
PubMed1999

Comparison of arcuate-legged clipped versus sutured hepatic artery, portal vein, and bile duct anastomoses.

Attempts at improving anastomoses have included the development of stapling techniques. Our purpose was to evaluate arcuate-legged clipped versus standard sutured anastomoses of the hepatic artery (HA), portal vein (PV), and bile duct in a porcine liver transplantation model. Two groups of pigs were studied intraoperatively and 1 day after liver transplantation. A control group underwent sutured anastomosis of PV and HA with polypropylene and of bile duct with polydioxanone (n = 8). An experimental group underwent anastomoses with arcuate-legged clips (n = 8). We analyzed the time to perform anastomosis and flows before and at various time points after anastomosis. In addition, patency and histology of the anastomoses were evaluated 1 day after operation, including a fibrin-thrombosis score, medial injury, and inflammation score. Times to complete HA and PV anastomoses were not different between clipped and sutured groups. However, the time was shorter to complete bile duct anastomosis with clips than with sutures (6.3 +/- 1.1 minutes and 13.3 +/- 2.0 minutes, respectively). Flows through HA anastomoses were not different between groups, but flow through the PV was higher in clipped compared with sutured anastomosis (P = 0.06). Patency was 100 per cent with no leaks for all three anastomoses in both groups. Histologic data were similar between vascular anastomotic groups. Sutured bile duct anastomoses revealed mild smooth muscle injury in 75 per cent whereas clipped bile duct anastomoses displayed no smooth muscle injury. We conclude that arcuate-legged clipped anastomosis represents a viable option to sutured anastomoses of the PV, HA, and bile duct anastomoses. Bile duct anastomoses were completed in less than half the time and with less tissue damage documented histologically.

Anastomosis, Surgical↗
PubMed1999

[Our experience with the use of Absolok polydioxanone resorbable clips in laparoscopic surgery].

BACKGROUND: The study aims to evaluate the efficacy of resorbable clips in polydioxanone in laparoscopic surgery. METHODS: The authors report their personal experience regarding the use of Absolok (ABL) resorbable clips in laparoscopic surgery. Out of a total of 745 laparoscopic operations performed from September 1992 to February 1997, 438 included the use of resorbable clips in place of metal clips, both for cystic duct section during cholecystectomy and vascular structures, or to lock continuous sutures. ABL clips were also used for major vessels (e.g. mesenteric artery) during laparoscopic colic resections. RESULTS: In all cases when they were used, ABL never gave rise to complications, such as biliary outflow or hemorrhage caused by the dislocation of the clips themselves. CONCLUSIONS: The authors conclude by affirming the value and safety of this type of clip.

Humans↗
PubMed2000

Sutureless vascular reconstruction with titanium clips.

Attempts to find alternatives to sutured vascular reconstruction techniques has continued for decades and include various forms of rings, tubes, endoluminal stents as well as gluing or welding techniques of large vessel anastomoses. One recently introduced technique uses nonpenetrating titanium clips for everted vessel approximation and closure. Experimental work on their use in various types of large vessel repairs and reconstructions has shown that the clips are easily applied with a short learning curve, create good conditions for vessel wall healing without causing excessive inflammation or fibrosis, and are considerably faster to apply when compared to standard suture techniques. Although there are some clinical reports of defective clipped closures causing postoperative bleeding complications, they are rare and most probably related to technical errors in applying the clips. The main disadvantages of the clips include the limited experience of their applicability in atherosclerotic vessels, lack of long term follow-up and cost. Potentially, the clips could be useful in the repair of multiple vascular injuries, in vessel repair or ligation performed in confined spaces, and in vascular procedures requiring the shortest possible cross-clamping time. Future applications could include endoscopic procedures as well as the use of a one-shot device which simultaneously applies up to a dozen clips to symmetrically everted and approximated vessel edges.

Animals↗
PubMed2001

Effectiveness of the ultrasonic coagulating shears, LigaSure vessel sealer, and surgical clip application in biliary surgery: a comparative analysis.

Advancements in laparoscopic surgery are often dictated by the limitations of technical instrumentation. Energy sources other than electrosurgery have become popular with the promise of quick and effective vascular control. With their success surgeons have begun using these on structures other than blood vessels with little or no data establishing their efficacy or safety. This study evaluates alternative energy sources in sealing ductal structures for possible use in liver or gallbladder surgery. After elective cholecystectomy cystic ducts (n = 45) were resealed ex vivo with surgical clips (n = 14), ultrasonic coagulating shears (n = 16), or electrothermal bipolar vessel sealer (n = 15), and bursting pressures were measured. Nineteen additional human cystic ducts were randomized to seal by ultrasonic coagulating shears (n = 9) or electrothermal bipolar vessel sealer (n = 10) and fixed in 10 per cent buffered formalin for histologic evaluation of thermal spread (mm). After this nine adult pigs were randomized to laparoscopic ligation and transection of the common bile duct using surgical clips (n = 3), ultrasonic coagulating shears (n = 3), or electrothermal bipolar vessel sealer (n = 3). The animals underwent necropsy for assessment of seal integrity on the sixth postoperative day. In the ex vivo study the mean cystic duct bursting pressure was 621 mm Hg with surgical clips and 482 mm Hg with the electrothermal bipolar vessel sealer (P = 0.39). The mean cystic duct bursting pressure after ultrasonic coagulating shears was 278 mm Hg, which was statistically less than surgical clips (P = 0.007) and electrothermal bipolar vessel sealer (P = 0.02). The mean thermal spread was 3.5 mm for ultrasonic coagulating shears and 13.4 mm for electrothermal bipolar vessel sealer (P = 0.0002). All animals undergoing ligation and transection of the common bile duct with ultrasonic coagulating shears and electrothermal bipolar vessel sealer developed bile peritonitis by postoperative day 6 as a result of seal leak. All animals undergoing surgical clip ligation and transection of the common bile duct maintained seal integrity. The mean common bile duct pressure above the surgical clip was 12 mm Hg (range 10-14). In conclusion the acute ex vivo study demonstrated a significant difference in the cystic duct bursting pressure between surgical clips and ultrasonic coagulating shears and between electrothermal bipolar vessel sealer and ultrasonic coagulating shears. The ultrasonic coagulating shears and electrothermal bipolar vessel sealer failed to maintain seal integrity in the in vivo animal study. Given the failure of the ultrasonic coagulating shears and electrothermal bipolar vessel sealer in the animal model these energy sources should not be used for transection of the cystic duct or major hepatic ducts during hepatobiliary surgery.

Animals↗
PubMed1985

[Recurrence of cerebral aneurysm after neck clipping--report of a case and review of literature].

A case of recurrent cerebral aneurysm after complete neck clipping is reported. A 38-year-old man was admitted to our service 14 days after attack of subarachnoid hemorrhage. On admission, ruptured left middle cerebral artery aneurysm with intercerebral hematoma and non-ruptured right anterior cerebral artery aneurysm were revealed by radiological examinations. Neck clipping was successfully performed to both of aneurysm and aneurysm was completely disappeard in the postoperative angiographical study. Postoperative course was also uneventful and he was discharged with slight right hemiparesis and motor aphasia. Thirteen months after the neck clipping, however, he was readmitted to our hospital with attack of subarachnoid hemorrhage. After admission, a new aneurysm was noted just under the clip at the right anterior cerebral artery. Neck clipping against this aneurysm was performed by reopening the craniotomy. For his postoperative normal pressure hydrocephalus, ventriculoperitoneal shunt was performed at one month after neck clipping. Postoperative course was uneventful and discharged. From review of literature, it was presumed that hemodynamic stress in the site of aneurysm and injury of arterial wall by the clip may be two major factors as a cause of recurrent aneurysm formation. In our case, possibility of the latter cause was suggested.

Adult↗
PubMed1984

Clinical comparison of Michel and Proximate clips used for abdominal wound closure.

For many years Michel clips (Down Surgical, Mississauga, Ont.) have been used to close wounds and results have been good, but several newer clips are now available (e.g., Proximate; Ethicon Sutures Ltd.), which are said to be easier to use and produce a better scar. However, they are much more expensive. The authors carried out a prospective controlled study in which 30 patients with abdominal incisions had half of the skin incision closed with Michel clips and the other half with Proximate clips. They assessed ease of insertion and removal, and appearance of the wound immediately after removal and 2 months later. Ethicon Proximate clips were, in general, slightly easier to insert, less uncomfortable to remove in 8 of the 30 patients and gave a better immediate cosmetic result in 9 patients. However, there was no difference in the appearance of the wound 2 months later. The authors do not consider that Ethicon Proximate clips offer an advantage over the much less expensive Michel clips.

Abdomen↗