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PubMed2003

A new experimental flap model: free muscle perforator flap.

A large number of perforator flap types have been described in experimental and clinical studies. Perforator flaps have been used both as pedicled and free flaps in clinical practice, but only in a pedicled form in animal studies. According to the authors' literature review, a free perforator flap in an animal model has not yet been developed. The purpose of this study was to describe a new free perforator flap model in the rat. A total of 15 Wistar rats weighing 200 to 250 g were used in this experiment. In 5 rats, the vascular anatomy of the popliteal vessels and their relation with adjacent structures were determined by anatomic dissection. In the remaining 10 rats, a posterior thigh perforator-based flap was created based on the distal popliteal vascular pedicle. In 5 rats the flap was transferred to the groin region as a free flap. In the remaining 5 rats the flap was transferred to the groin region, but in this group anastomosis was not performed between the vascular structures of the flap and the recipient femoral vessels. The latter group was designated as the control group. Direct observation and microangiographic techniques were used to assess the viability of the flap. Results showed that the cutaneous islands of all the free flaps survived completely, whereas in the control group all the flaps under-went total necrosis. The authors conclude that the free posterior thigh perforator flap is a reliable and true perforator flap model for future physiologic, biologic, and pharmacologic studies. It offers the following advantages: 1) Arising from the biceps femoris muscle, the musculocutaneous perforator of the flap has a consistent vascular pedicle, 2) it is the first free perforator flap for the rat, 3) it is harvested from a small-animal species, and 4) it can be used without the need for an isogeneic rat.

Animals↗
PubMed1993

Errors in the assessment of tympanic membrane perforations.

It is commonly stated that operative closure of large perforations of the tympanic membrane is less successful than closure of small perforations. Few authors mention the exact size of the perforations studied, and fewer still give their method of measuring perforations. We describe a photographic method of assessing the size of perforations relative to the total drumhead, measuring them with a computerized digitizing pad. Thirteen temporal bones were selected at random. Perforations of different sizes, shapes and at different sites were fashioned in the tympanic membranes. These were assessed by clinicians of all grades, who were asked to draw the perforations and give estimates of the perforation size as a percentage of the total drumhead. Visual estimates and drawings were compared with a photographic objective method. Gross errors (some in excess of 100%) were apparent in both estimates and drawings. There was a highly significant statistical difference between the objective method and visual estimates and drawings (P < 0.001). Greater clinical experience was not correlated with better performance in estimating the size of perforations.

Diagnostic Errors↗
PubMed2007

Effect of placement of calcium sulphate when used for the repair of furcation perforations on the seal produced by a resin-based material.

AIM: To evaluate the sealing ability of calcium sulphate when used under composite resin for the repair of furcation perforations having different diameters. METHODOLOGY: Perforations of different diameter were created in the floors of pulp chambers in 60 extracted human molar teeth with either a number 3 (1 mm diameter) or 5 (1.5 mm diameter) round bur. The specimens of each group were divided into four sub-groups which were repaired with composite resin either alone or in combination with calcium sulphate that created an artificial floor (15 teeth group(-1)). Eight teeth without furcation perforations served as negative controls. In the leakage detection device, 1 mol L(-1) glucose solution was forced under a pressure of 1.5 KPa from the crown towards the pulp chamber floor. The concentration of leaked glucose was measured at 1, 2, 4, 7, 10, 15 and 20 days using a glucose oxidase method and the data evaluated using the rank sum test. RESULTS: The specimens with larger perforations repaired with composite resin alone had significantly more leakage (P < 0.05). Using calcium sulphate as an artificial floor significantly decreased leakage of smaller perforations (P < 0.05). In groups repaired with calcium sulphate under composite resin, leakage in smaller perforations was markedly lower than that in larger ones (P < 0.05). No significant difference was found between the specimens with 1 or 1.5 mm perforations repaired with resin alone (P > 0.05). CONCLUSIONS: Calcium sulphate significantly improved the sealing ability of 1 mm perforations repaired with composite resin but not for 1.5 mm perforations.

Calcium Sulfate↗
PubMed1991

Repair of chronic tympanic membrane perforations using applications of hyaluronan or rice paper prostheses.

A controlled randomized study was performed in 60 patients with 64 chronic, dry tympanic membrane (TM) perforations. The perforations were randomly allocated to either resection of the perforation rim and instillation of 1% hyaluronan (Healon; HYA) in the perforation gap once daily for 7 days (33 ears) or resection of the perforation margin and application of a sterile rice paper prosthesis (31 ears). The treatment effect was documented by TM photography and morphometric measurements of the perforation area. The hearing was assessed with puretone and high-frequency audiometry. After 2 months, 5 of the HYA-treated perforations (15%) and 4 of the rice-paper-treated TMs (13%) were healed. After 1 year, 18 perforations (9 in each treatment group) were healed. In neither group were there any persistent adverse effects on hearing. It is noteworthy that 28% (18/64) of the chronic, long-standing TM perforations could be repaired by these technically simple and time-saving methods. Both procedures should be considered as easy first-choice alternatives to myringoplasty in selected cases.

Adolescent↗
PubMed1993

Animal model for persistent tympanic membrane perforations.

Topically applied hydrocortisone was used to develop an animal model for persistent tympanic membrane (TM) perforations. Hydrocortisone suspension was applied on the margins of TM perforations of standardized size in rats once daily for 10 days. The healing patterns of the TMs were mapped weekly and, when the perforations were about to close, daily. After 50 days, all hydrocortisone-treated perforations were open, whereas the controls closed within 9 to 12 days. At 3 months, when one third of the perforations still were open, the TMs were studied by otomicroscopy and light microscopy. All TMs were thickened and covered by keratin and wax. The thickened epidermal layer at the border of the TM perforations that remained open also draped the surface of the perforation facing the middle ear cavity. The thickened connective tissue layer contained abundant fibroblasts with their axes of length oriented at random. Both application of 1.4% hyaluronan and wounding of the perforation border enhanced the healing rate of the hydrocortisone-induced chronic TM perforation.

Animals↗
PubMed2006

Spectrum of perforation peritonitis in India--review of 504 consecutive cases.

BACKGROUND/OBJECTIVE: Perforation peritonitis is the most common surgical emergency in India. The spectrum of etiology of perforation in Tropical countries continues to be different from its Western counterpart. The objective of the study was to highlight the spectrum of perforation peritonitis as encountered by us at Government Medical College and Hospital (GMCH), Chandigarh. METHODS: Five hundred and four consecutive cases of perforation peritonitis over a period of five years were reviewed in terms of clinical presentation, operative findings and postoperative course retrospectively at GMCH, Chandigarh. RESULTS: The most common cause of perforation in our series was perforated duodenal ulcer (289 cases) followed by appendicitis (59 cases), gastrointestinal perforation due to blunt trauma abdomen (45 cases), typhoid fever (41 cases) and tuberculosis (20 cases). Despite delay in seeking medical treatment (53%), the overall mortality (10%) was favourably comparable with other published series though the overall morbidity (50%) was unusually high. CONCLUSION: In contrast to western literature, where lower gastrointestinal tract perforations predominate, upper gastrointestinal tract perforations constitute the majority of cases in India. The increasing incidence of post-traumatic gastro-enteric injuries may be due to an increase in high speed motor vehicle accidents which warrant early recognition and prompt treatment to avoid serious complications and death.

Journal Article↗
PubMedDate not supplied

An analysis of contemporary morphological concepts of synaptic remodelling in the CNS: perforated synapses revisited.

Perforated synapses refer to a synaptic type found in the central nervous system. They are characterized by their large size and by a discontinuity of the postsynaptic density when viewed in transverse sections, and by a doughnut or horseshoe shape when viewed in en face views. Of recent morphological studies, one approach has followed their characteristics throughout development and maturity, while others have concentrated on their probable roles in activities including kindling, long-term potentiation, spatial working memory, differential rearing, and the functioning of neuroleptics. An assessment is made of the hypotheses and models that have proved determinative in the emergence of perforated synapses as being significant in synaptic plasticity. Their distribution and frequency are summarized, with emphasis on the importance of unbiased stereological procedures in their analysis. Using three-dimensional approaches various subtypes are recognized. Of these, a complex or fragmented subtype appears of especial significance in synaptic plasticity. Ideas regarding the life-cycle of perforated synapses are examined. The view that they originate from conventional, non-perforated synapses, enlarge, and subsequently split to give rise to a new generation of non-perforated synapses, is critically assessed. According to an alternative model, perforated and non-perforated synapses constitute separate populations from early in their development, each representing complementary forms of synaptic plasticity. An attempt is also made to discover whether synaptic studies on the human brain in normal aging and in Alzheimer's disease throw light on the role of perforated synapses in synaptic plasticity. The loss of synapses in Alzheimer's disease may include a loss of perforated synapses - of particular relevance for an understanding of certain neuropathological conditions.

Aging↗
PubMed2006

Effects of sinus membrane perforations on the success of dental implants placed in the augmented sinus.

BACKGROUND: Maxillary sinus lifting procedure enables clinicians to place implant-supported prostheses even in cases with very limited vertical bone height of the maxillary sinus. The aim of this study was to evaluate the implant success with regard to effects of the sinus membrane perforations that occurred during sinus lifting surgery. METHODS: The study group consisted of 91 patients (29 females and 54 males) with edentulous posterior maxilla. Implant placement combined with sinus lifting surgery was performed, and 259 implants were inserted. Sinus membrane perforations were detected in 12 sinus sites. After proper treatment of perforations, 26 implants were placed into perforated sinus areas. Baseline panaromic radiographs were taken before the beginning of prosthetic treatment. Panaromic radiographs taken at the last recall were used for evaluation and compared to the baseline panaromic radiographs using image analysis software to reveal the peri-implant resorption rate for the implants placed in perforated and non-perforated sinus area. The modified sulcus bleeding index and plaque index were used for the assessment of soft tissue conditions. RESULTS: Eleven implants were lost during the follow-up period, resulting in an overall survival rate of 95.9%. Two failures occurred in the group with sinus perforations. There was no statistically significant difference regarding peri-implant bone resorption (P = 0.778) and soft tissue conditions for implants placed into perforated-augmented sinus areas and augmented sinus areas. CONCLUSION: Within the limits of this study, perforation of the sinus membrane did not compromise the osseointegration process or the success of dental implants placed in the augmented maxillary sinus.

Adult↗
PubMed1985

Perforating branches of the middle cerebral artery. Microsurgical anatomy of their extracerebral segments.

Perforating branches of the middle cerebral artery (MCA) were examined under magnification in 50 formalin-fixed brain hemispheres. Perforating vessels varied in number from three to 18, with an average of nine. The greater the number of vessels, the smaller was their diameter. In this study, the perforating arteries were divided into medial, middle, and lateral groupings. Those in the medial group usually arose directly from the MCA main trunk close to the carotid bifurcation. There were usually three vessels in the middle group, which originated not only from the MCA trunk, but also from the MCA collateral (cortical) branches. Common stems, when present, gave rise to individual perforating vessels and occasionally to thin olfactory and insular rami. Perforating arteries in the lateral group varied from one to nine in number. In addition to an origin from the MCA trunk, they also arose from cortical branches supplying the frontal and temporal lobes. The fact that lateral perforating vessels often originated from division sites and from terminal branches of the MCA is of clinical significance, because aneurysms are more commonly located at the MCA bifurcation. Anastomoses were not found among the perforating arteries. In two specimens, a fusion between a perforating artery and the MCA trunk was noted. Since the perforating vessels are obviously end arteries, injury to them must be avoided during operations for MCA aneurysms.

Cerebral Arteries↗
PubMed2001

[A clinical investigation of oro-maxillary sinus-perforation due to tooth extraction].

Oro-maxillary sinus perforation occurs occasionally at the extraction of a maxillary tooth, and it may be a cause of maxillary sinusitis or antro-oral fistula. Our purpose was to investigate the most frequent site of perforation, and to understand the clinical course of patients after perforation. We examined 2,038 maxillary teeth extracted from 1,337 patients (473 males and 864 females) at the First Department of Oral and Maxillofacial Surgery, Tokyo Medical and Dental University, from January 1991 to December 1993. Perforation occurred in 77 of all 2,038 teeth (3.8%). Of these, 38 teeth were from males (38/733; 5.2%), and 39 were from females (39/1,305; 3.0%). The perforation rate was significantly higher in males. Perforation occurred most often with extraction of an upper first molar, and in the third decade of life. The perforation rate gradually decreased with higher age. We classified 38 cases into 3 categories according to panorama X-P: 1) The tip of the root crossed over the bottom line of the maxillary sinus (29 cases), 2) Not crossed over distinctly (4 cases), 3) Just lie on, or whether the tip of the root crossed over the bottom line of the maxillary sinus was not distinct (5 cases). As to treatment, 30 perforations (39.0%) closed spontaneously in the course of observation, irrigation with physiological saline was used in 43 cases (55.8%), radical sinusotomy accompanied by closure of the perforation was performed in 4 cases, and only flap closure was used in 7 cases. There were no cases of relapse.

Adult↗
PubMedDate not supplied

Management of vascular perforations that occur during neurointerventional procedures.

This article describes a number of treatment strategies for the management of perforations that occur during neurointerventional procedures. During the past 5 years, we have performed over 1200 endovascular procedures to treat vascular disorders involving the brain and spinal cord (400 cerebral arteriovenous malformations, 230 tumors, 197 carotid cavernous fistulas, 183 aneurysms, 130 dural fistulas, 80 spinal arteriovenous malformations, 18 vein of Galen aneurysms, and 20 cases of vasospasm). Fifteen patients (1.1%) sustained a vascular perforation as a direct result of these procedures. Among these 15 patients, indications for endovascular treatment were six symptomatic arteriovenous malformations, two spinal cord arteriovenous malformations, two cavernous sinus dural fistulas, one transverse sinus fistula, one case of vasospasm following subarachnoid hemorrhage, one direct carotid cavernous fistula, one vein of Galen malformation, and one ruptured basilar artery aneurysm. The vascular perforations were grouped into three probable mechanisms: mechanical perforation of a normal vessel (six patients), mechanical disruption of a dysplastic vessel or aneurysm (five patients), and fluid overinjection (four patients). Treatment of the perforations included immediate reversal of anticoagulants (12 patients) and direct closure of the perforation site with coils (five patients). In addition, closure of the intravascular compartment adjacent to the perforation was achieved with coils (six patients), liquid adhesives (four patients), balloons (two patients), or particles (two patients). In two patients a detachable balloon was placed transiently across the perforation site for several minutes, deflated, and removed when no further extravasation was noted. Five patients were started on anticonvulsant therapy, two of whom have had a new onset seizure related to the perforation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

The effect of double gloving on frequency of glove perforations.

OBJECTIVE: The purposes of this prospective investigation were to determine the frequency of glove perforation during obstetric and gynecologic procedures and to assess the value of double gloving in preventing damage to the inner glove. METHODS: During a 2-month period, surgeons in the Department of Obstetrics and Gynecology were asked to double glove during all operative procedures. At the conclusion of surgery, the gloves were collected and the surgeons noted the type of procedure and their role as primary surgeon or first assistant. They also indicated whether a perforation was recognized intraoperatively. The gloves were tested for damage by first filling them with air and immersing them in water and then by directly filling them with water. RESULTS: Four hundred forty-one sets of double gloves were evaluated. Of these, 61 sets (14%, 95% confidence interval 10.8-17.2%) had holes in at least one of the four gloves and six sets had more than one perforation, for a total of 67 holes. Fifty-two holes (78%) penetrated only the outer glove and nine (13%) were only in the inner glove. Penetration of both gloves at identical sites occurred in only six of the total glove sets (1.4%, 95% confidence interval 0.3-2.5%). The two most common sites of perforation were the thumb and index finger of the nondominant hand. Glove perforation occurred in 15% of cesarean deliveries and 11% of vaginal deliveries, a nonsignificant difference. In contrast, penetration occurred in 28% of major gynecologic procedures (P less than .05 compared with cesarean or vaginal delivery). Chief and third-year residents were significantly more likely to sustain perforation than were attending physicians or junior residents (P less than .01). Perforation to the gloves of chief residents typically occurred while they were serving as assistants for first- and second-year residents. Third-year residents usually sustained perforations while functioning as primary surgeons. CONCLUSIONS: Glove perforations occur with relatively high frequency during pelvic surgery, particularly abdominal procedures. Double gloving offers a measure of protection against damage to the inner glove and may prevent subsequent exposure of the surgeon to blood and other body fluids.

Gloves, Surgical↗
PubMed1985

Factors contributing to perforations resulting from laser coronary angioplasty: observations in an intact human postmortem preparation of intraoperative laser coronary angioplasty.

This investigation was designed to assess the potential use of laser coronary angioplasty as an intraoperative adjunct in the surgical treatment of ischemic heart disease. Among 17 postmortem hearts, simulated laser coronary angioplasty was performed at 53 sites with a No. 4F guiding catheter and 240 micron (200 micron core) quartz optical fiber. Perforation complicated laser coronary angioplasty in 33 (62%) of the 53 attempts. Most (n = 29) perforations were thermal; four were purely mechanical. Perforation sites were characterized by extensive calcific deposits (21 of 33 cases [64%] ) and the origin of a side branch (13 of 33 [39%] ). Excessive tortuosity of the extramural coronary artery contributed to arterial perforation in four cases, and precluded attempts to perform laser coronary angioplasty in two other cases. In 19 of the 53 attempts to perform laser coronary angioplasty, a high-frequency two-dimensional echocardiographic probe was used to image the coronary artery during antegrade manipulation of the optical fiber/guiding catheter and laser irradiation of the target arterial stenosis. Although perforation nevertheless occurred in 11 (58%) of 19 sites, only one mechanical perforation resulted; the remaining 10 were thermal. Characteristics of the perforation sites in this group were similar to those noted for the group as a whole. Experience with this model of laser coronary angioplasty indicates that even when access problems associated with percutaneous laser coronary angioplasty are obviated by a simulated intraoperative approach, perforation of the underlying coronary arterial wall continues to represent the "rate-limiting" complication of laser coronary angioplasty. Most perforations occurred in relation to calcific deposits, branch points, and tortuous coronary segments.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Synaptic plasticity and perforated synapses: their relevance for an understanding of abnormal synaptic organization.

Perforated synapses refer to a synaptic type found in the central nervous system, and characterized by a discontinuous postsynaptic density when viewed in transverse sections; they are doughnut-shaped or horseshoe-shaped when viewed in en face views. They are large, and are considered to represent single synapses. In this review the evidence for their being intermediates in synaptic turnover is examined. In particular, the view that they originate from conventional, non-perforated synapses, enlarge, and subsequently split to give rise to a new generation of non-perforated synapses, is critically assessed. It is concluded that all the necessary stages in such a scheme have not been unequivocally demonstrated, and an alternative is considered. According to this, perforated and non-perforated synapses constitute separate populations from early in their development, each representing complementary forms of synaptic plasticity. It is further argued that the perforated synapse population can be subdivided into synapses with simple, discrete perforations, those with re-entrant zones, and those with a more complex fragmented form of organization. There is evidence that it is synapses of the latter type that are implicated in synaptic plasticity. An attempt is also made to discover whether the results of synaptic studies on both the normal ageing human brain and the brain in Alzheimer's disease, throw light on the role of perforated synapses in synaptic plasticity. It is suggested that there may be a loss of perforated synapses in Alzheimer's disease, although definitive data are required to test this possibility.

Age Factors↗
PubMed1991

Peptic ulcer perforation as the presentation of Zollinger-Ellison syndrome.

We examined the characteristics of patients with Zollinger-Ellison syndrome who developed a perforation prior to diagnosis to determine whether any clinical features were useful markers of the syndrome. Of 160 patients with Zollinger-Ellison syndrome, perforation occurred prior to the diagnosis being made in 11 (7%). At surgery, perforations were found in the duodenum in six cases and in the jejunum in five. In no case was tumor identified at emergency surgery, and the diagnosis of Zollinger-Ellison syndrome was made only in the postoperative period when excessive gastric secretions were noted. Neither acid output nor serum gastrin concentration were useful predictors for perforation. The patients, six men and five women, were 27-61 years old (median 48) and one had MEN-1. Three patients had no symptoms prior to the perforation. The other eight had symptoms for 1-15 years, with diarrhea occurring in 45% of the cases. Following the diagnosis of Zollinger-Ellison syndrome, patients were given medication to control gastric acid hypersecretion. Eight patients remained well, but the three patients who had had a partial gastrectomy had a complicated course despite medical therapy. Although features of perforation in Zollinger-Ellison syndrome are not specific, jejunal perforation or perforation associated with a history of diarrhea is suggestive of the diagnosis. Serum gastrin should be measured in every case and a partial gastrectomy avoided.

Adult↗
PubMed1989

The frequency and management of uterine perforations during first-trimester abortions.

The frequency and management of uterine perforation during first-trimester abortions remain a matter of continuing debate among gynecologists. The rate of uterine perforations was 1.3/1000 procedures (eight cases) in 6408 women undergoing first-trimester abortions at our clinic. We also performed 706 first-trimester abortions at the time of laparoscopic sterilization. Two perforations (2.8/1000 procedures) were reported before laparoscopy. Twelve (15.6/1000 procedures) unsuspected perforations were discovered during direct laparoscopic visualization. This represents a 19.8/1000 procedure rate of perforation (14 cases). All 22 patients with perforations were managed conservatively, and no immediate or late complications were noted. Our data suggest that the true incidence of uterine perforations is significantly underestimated and serious complications caused by perforations are rare. Conservative therapy is recommended rather than early surgical intervention.

Abortion, Induced↗
PubMed1994

[The IUD and uterine perforation].

The intrauterine device (IUD) is an effective and relatively safe contraceptive. Approximately 15% of women of child-bearing age in Italy use the IUD. The major health risks associated with IUD use are perforation of the uterus, pregnancy (both intrauterine and ectopic), and pelvic inflammatory disease. Perforation of the uterus by an IUD is a serious complication and this is possible both during the insertion and later. Perforation of the uterus is rare, but potentially fatal. The incidence is of 0.12-0.68/1000 insertion. Although some patients have signs and symptoms suggestive of perforation (pain or bleeding), many are apparently asymptomatic at the time the diagnosis of perforation is made. Perforation is often suspected or diagnosed when the IUD string is no longer visible at the external os. A patient who has sustained a perforation is not protected against pregnancy. Numerous factors affect perforation: the type of IUD, the uterine size and position, timing of the insertion in relation to the last delivery or abortion and the experience of the clinical. Serious consequences have been described, such as severe damage to the viscera (i.e. bowel, kidney) and/or peritonitis. The diagnosis is clinical, ultrasonic, radiological and coelioscopic. Coelioscopic diagnosis makes it possible to choose the method of treatment. In experienced hands, this method is rapid, the hospitalization required short and the sequelae simple.

Adolescent↗
PubMed1998

Perforated duodenal ulcer: an alternative therapeutic plan.

An alternative plan for the treatment of a perforated duodenal ulcer is proposed. We will focus on the now-recognized role of Helicobacter pylori in the genesis of the majority of duodenal ulcers and on the high rate of success of therapy with a combination of antibiotics and a proton-pump inhibitor or histamine2 blocker in treatment of such ulcers. Knowledge that half the cases of perforated duodenal ulcer may have securely sealed spontaneously at the time of presentation is incorporated in the therapeutic plan. Patients with a perforated duodenal ulcer who have already been evaluated for H pylori and are not infected or, if infected, have received appropriate therapy should undergo an ulcer-definitive operation if they are suitable surgical candidates. Most authorities recommend surgical closure of the perforation and a parietal cell vagotomy. The remaining patients should have a gastroduodenogram with water-soluble contrast medium. If the perforation is sealed, the patient can be treated nonsurgically. If the perforation is leaking, secure surgical closure of the perforation is necessary. Following recovery from the immediate consequences of the perforation, evaluation for H pylori should be conducted. If the patient is infected, combined medical therapy is recommended. If the patient is not infected, Zollinger-Ellison syndrome should be ruled out and medical therapy is recommended if the ulcer has not been treated previously. Elective ulcer-definitive surgery should be considered for the occasional uninfected patient who has already received appropriate medical therapy for the ulcer.

Algorithms↗