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PubMed1998

Clinical-histopathological correlations of pitfalls in middle ear surgery.

Significant anatomical variations within the middle ear are described as well as atypical histopathological findings in 13 selected human temporal bones. Bones studied included such vascular and bony abnormalities as carotid artery canal dehiscence, a high jugular bulb, persistent stapedial artery and facial nerve canal dehiscences. Bones also included obliterative otosclerosis, malleus head fixation and a variety of chronic inflammatory changes and/or sequelae. Those features considered to render cases prone to complications are detailed.

Ear, Middle↗

PubMed1999

Relationship of the distal optic nerve sheath to the circle of Zinn.

BACKGROUND: This study was designed to determine the relationship of the vascular circle of Zinn (CZ) and its branches to the termination of the subarachnoid space surrounding the optic nerve sheath, with particular reference to optic disc size. METHODS: Serial sections of 29 normal human optic nerves were performed at 6-microm intervals. The position of the CZ and subarachnoid space were measured with WILD Heerbrugg objective graticules. The results were analysed with reference to the optic disc size. RESULTS: The position of the CZ was variable but two major types were recognised. In type 1 the circle was located anterior to the distal sheath, and in type 2 posterior to the sheath. There were more small optic discs observed in type 2. CONCLUSION: In this study the CZ was more posteriorly located in small optic discs. This location may induce risk factors contributing to the development of ischaemic optic neuropathy. The combination of small discs, posterior placement of the CZ, and anatomical variations in the vascular pattern may predispose to ischaemic events.

Cadaver↗

PubMed2001

Transvenous embolization of carotid cavernous fistulas via the superior ophthalmic vein.

BACKGROUND: Treatment of choice for symptomatic carotid-cavernous and cavernous-dural fistulas is neuroradiologic intervention via the femoral artery. Owing to the location of the fistula and/or to anatomic variations, a direct surgical approach via the superior ophthalmic vein may be necessary for embolization. METHODS: Three patients presented with exophthalmos, episcleral venous congestion, chemosis, restricted eye movement, and secondary glaucoma. One patient had visual impairment and scotoma due to compression of the optic nerve by the fistula. The tentative diagnosis of an arteriovenous fistula was confirmed in two cases by color Doppler imaging and in all three cases with cerebral arterial angiography (two carotid-cavernous fistulas, one cavernous-dural fistula). After an unsuccessful transarterial attempt, embolization via the superior ophthalmic vein was chosen. RESULTS: In all three patients the preparation of the superior ophthalmic vein was performed without any complications. In two cases the fistula could be embolized completely with platinum coils. In one patient the placement of the microcatheter was impossible, because of an abnormal vascular pattern. Later on the fistula was successfully embolized by an approach via the femoral vein. All three patients had complete resolution of symptoms. There were no recurrences. CONCLUSION: Embolization of carotid-cavernous and cavernous-dural fistulas by a surgical approach via the superior ophthalmic vein represents safe and effective treatment when standard transarterial access is impossible. The cooperation of an orbital surgeon and an invasive neuroradiologist can be of benefit for this rare group of patients.

Aged↗

PubMed2005

Mophometric study of the aortic arch and its major branches in rat fetuses on the 21st day of gestation.

The anatomy and embryology of the aortic arch and its branching tributaries (brachiocephalic trunk, left common carotid artery and left subclavian artery) in man and animals are well substantiated. However, the anatomical variations and morphometry of the aortic arch and its branching tributaries in rat fetus at the 21st gestation day have not been studied. Pregnant rats were hysterectomized and the arterial systems of 114 fetuses were injected with a polymerisable resin through the umbilical artery. After maceration, the vascular casts were dissected out and prepared for observations under a scanning electron microscope (SEM). The resulting SEM pictures were studied with a picture analyser and different vessel parameters (diameters, lengths and angles) were measured. The success rate of the microvascular cast injection was 46.5%. Out of the 53 observed aortic arch casts, 98.1% showed the classical branching pattern and one (1.9%) had no brachiocephalic trunk. Morphological analysis showed many differences, which were not linked to the litter. The statistical processing of the measurements enabled us to determine that the aorta diameter after the branching of the left subclavian artery was the most replicable parameter. Moreover, the results revealed some strong correlations between different parameters. There are probably no discrete categories among the various observed parameters as diameters and angles. Some parameters show very little variability and can thus be used as reference points for further studies such as the comparison of a control population with a population treated with a relevant xenobiotic.

Age Factors↗

PubMed2004

Aberrant left hepatic artery in laparoscopic antireflux procedures.

BACKGROUND: The aberrant left hepatic artery (ALHA) is an anatomic variation that may present an obstacle in laparoscopic antireflux procedures. Based on our experience, we addressed the following questions: How frequent is ALHA? When or why is it divided? What is the outcome in patients after division of the ALHA? METHODS: From a prospective collected database of 720 patients undergoing laparoscopic antireflux surgery, we collected the following information: presence of an ALHA, clinical data, diagnostic workup, operative reports, laboratory data, and follow-up data. RESULTS: In 57 patients (7.9%) (37 men and 20 women; mean age, 51 +/- 15.7 years), an ALHA was reported. Hiatal dissection was impaired in 17 patients (29.8%), requiring division of the ALHA. In three patients (5.3%), the artery was injured during dissection; in one case (1.8%), it was divided because of ongoing bleeding. Ten of the divided ALHA (55.5%) were either of intermediate size or large. Mean operating time was 2.2 +/- 0.8 h; mean blood loss was 63 +/- 49 ml. Postoperative morbidity was 5.3% and mortality was 0%. None of the patients with divided hepatic arteries had postoperative symptoms related to impaired liver function. Postoperatively, two patients (11.7%) had transient elevated liver enzymes. At a mean follow-up of 28.5 +/- 12.8 months, no specific complaints could be identified. CONCLUSIONS: ALHA is not an uncommon finding in laparoscopic antireflux surgery and may be found in > or =8% of patients. Division may be required due to impaired view of the operating field or bleeding. Patients do not experience clinical complaints after division, but liver enzymes may be temporarily elevated.

Adult↗

PubMed2000

Intraoperative cholangiography during laparoscopic cholecystectomy.

BACKGROUND: The routine use of intraoperative cholangiography (IOC) during laparoscopic cholecystectomy remains controversial. METHODS: A retrospective review of 950 consecutive laparoscopic cholecystectomies performed during an 8-year period was performed. For the first 2 years, IOC was performed selectively, and thereafter routinely. RESULTS: Attempted in 896 patients, IOC was successful in 734 (82%). Bile duct stones were found in 77 patients (10%), dilated ducts without stones in 47 patients (6%), and anatomic variations in 4 patients (0.5%). There were four (0.4%) minor intraoperative complications related to the IOC, with no consequences for the patients. There were three (0.3%) minor injuries of the bile duct, which were identified with IOC and repaired at the time of cholecystectomy without any consequences for the patients. In two of these patients, the structure recognized and catheterized as the cystic duct was revealed by IOC to be the bile duct. Thus IOC prevented extension to a major common bile duct (CBD) injury. CONCLUSIONS: Findings show that IOC is a safe technique. Its routine use during laparoscopic cholecystectomy may not prevent bile duct injuries, but it minimizes the extent of the injury so that it can be repaired easily without any consequences for the patient. The prevention of a major bile duct injury makes IOC cost effective.

Adolescent↗

PubMed1996

Confluence of the right adrenal vein with the accessory right hepatic veins. A potential hazard in laparoscopic right adrenalectomy.

Confluent drainage of the right adrenal vein and large accessory right hepatic veins was encountered during a laparoscopic right adrenalectomy. In a review of previous reports of laparoscopic adrenalectomies we found no mention of this finding. However, an anatomic study reported that the right adrenal vein joins with an accessory right hepatic vein in as many as 22% of individuals. A complete understanding of the anatomic variations in the drainage of the right adrenal vein is required for the safe performance of laparoscopic right adrenalectomy.

Adrenal Glands↗

PubMed2006

The impact of 3-D virtual hepatectomy simulation in living-donor liver transplantation.

BACKGROUND/PURPOSE: In living-donor liver transplantation, accurate assessments of liver graft volume and anatomical variation are mandatory for the preoperative planning of safe donor hepatectomy and successful recipient implantation. The aim of this study was to assess the feasibility and accuracy of novel three-dimensional (3-D) virtual hepatectomy simulation software in living-donor liver transplantation. METHODS: We developed the hepatectomy simulation software, which was programmed to analyze detailed 3-D vascular structure and to predict liver graft volume, based on hepatic circulation. RESULTS: In 101 individuals, including 4 living donors, the predicted liver resection volumes revealed a significant correlation with the actual value (P < 0.0001), with a mean difference of 7.9 ml. The drainage area by the individual hepatic vein branch was quantified to achieve reconstruction of the corresponding venous branch. The application of multidetector computed technology scanning and virtual cholangioscopy facilitated more detailed visualization of the 3-D hilar anatomy in a left trisectoral graft transplantation. CONCLUSIONS: This hepatectomy simulation software reliably predicted accurate liver graft volume and the drainage volume of hepatic vein branches. This software may contribute to the preoperative planning of safe donor hepatectomy and implantation with satisfactory graft viability.

Female↗

PubMed2002

Living-donor liver transplantation in the new decade: perspective from the twentieth to the twenty-first century.

Liver transplantation from living donors developed rapidly in the last decade of the twentieth century and is now an important option in the treatment of patients with end stage and/or irreversible liver diseases. Although the disadvantages of small-for-size grafts are being significantly mitigated by the repertoire of left lobe, while left liver, and right lobe grafts, the struggle for graft size matching has disclosed not a few problems, such as small grafts for advanced disease, anatomical variations in donor livers, and, above all, the increasing importance of donor safety. The range of donor candidates is also an important point of discussion in regard to the social significance of this treatment modality. Apart from the surgical aspects, many medical aspects, including the indications and timing of transplantation specific to this technique, the prevention of disease transmission in family members, and immunological aspects, including the risk of graft-versus-host disease, remain to be clarified. Social and economic questions, as well as surgical and medical issues, will be the theme in the second decade, and the new century, of this newborn treatment modality.

Forecasting↗

PubMed1998

Avoiding muscle cutting while extending McBurney's incision: a new surgical concept.

Extending a McBurney's muscle-splitting incision, to achieve a better exposure when performing a difficult appendectomy, by muscle cutting may be associated with an increase in patient morbidity. In a retrospective study we Verified two actual indications that call for wound extension. The first is to correct a malpositioned first incision that does not match an existing anatomical variation in the region of the appendix. The second is to achieve a wide surgical space to deal with complicated cases. For each of these two indications, we thus introduced a new technique that fulfills the real requirement without muscle cutting. For the first indication we used a double muscle-splitting incision, while for the second indication we combined the original muscle-splitting incision with a vertical incision of the posterior lamina of the anterior rectus sheath. The two techniques are herein presented and the results of their application in 126 cases are discussed.

Adolescent↗

PubMed2000

Idiopathic segmental infarction of the greater omentum successfully treated by laparoscopy: report of case.

Idiopathic or spontaneous segmental infarction of the greater omentum (ISIGO) is a rare cause of acute right-sided abdominal pain. The symptoms simulate acute appendicitis in 66% of cases and cholecystitis in 22%. Progressive peritonitis usually dictates laparotomy, and an accurate diagnosis is rarely made before surgery. The etiology of the hemorrhagic necrosis is unknown, but predisposing factors such as anatomic variations in the blood supply to the right free omental end, obesity, trauma, overeating, coughing, and a sudden change in position may play a role in the pathogenesis. We present herein the case of a 37-year-old man in whom ISIGO, precipitated by obesity and overeating, was successfully diagnosed and treated by laparoscopy. Resection of the necrotic part of the greater omentum is the therapy of choice, and ensures fast recovery and pain control. Serohemorrhagic ascites is a common finding in ISIGO, and careful exploration of the whole abdominal cavity should be performed. The laparoscopic approach allows both exploration and surgical intervention.

Abdomen, Acute↗

PubMed2004

Distal femoral cut perpendicular to the mechanical axis may induce varus instability in flexion in medial osteoarthritic knees with varus deformity in total knee arthroplasty: a pitfall of the navigation system.

Two factors that influence the external rotation angle of the femoral rotational axis in total knee arthroplasty (TKA) were assessed in 40 medial osteoarthritic knees with varus deformity. First, the anatomic configuration of the femur was assessed using standardized radiographs of the patients' lower extremities before TKA. Second, the degree of medial soft tissue release was assessed during TKA. The radiographs showed that the characteristics of the femur were lateral bowing of the shaft and external rotation of the condyle in the coronal plane. Therefore, when the distal femur is cut perpendicular to the mechanical axis, the cut surface may be in too much of a valgus position. Furthermore, some degree of medial soft tissue release was necessary in all knees. Medial soft tissue release rotates the femur externally in extension in the coronal plane, and it rotates the femur externally around the femoral axis in flexion relative to the tibia. A distal femoral cut in too much of a valgus position and medial soft tissue release induces varus instability in flexion in knees with lateral bowing of the femoral shaft. Anatomic variation such as femoral bowing should be considered when a navigation system is used for TKA because the navigation system shows only the mechanical axis.

Aged↗

PubMed2002

[Life threatening oral hemorrhage after implantation into the distal right mandible].

In dental practice, surgical implant procedures are frequently conducted for pre-prosthetic surgery. Intra-operative complications are rare and can mostly be prevented effectively with adequate preparatory measures. However, not all risks can be anticipated a priori. Anatomical variation, such as variation in the path of blood vessels, is often unpredictable. This paper describes a life-threatening hemorrhage that occurred in a 60-year-old male during the insertion of an implant in the distal right mandible. It was impossible to stop the bleeding using local measures. Only extraoral ligation of the facial artery proved effective in suppressing the hemorrhage. The submentalis artery, a branch of the facial artery, had an atypical path directly below the caudal ridge of the mandible. The possibility of similar complications should make us re-evaluate preoperative preventive measures, and places greater demands on intra-operative complication prophylaxis. The international literature on this topic is discussed.

Arteries↗

PubMed2006

[Interdisciplinary treatment of carotid cavernous fistulas via the superior ophthalmic vein].

BACKGROUND: The endovascular occlusion of symptomatic carotid cavernous fistulae (CCF) via the transfemoral approach is safe and effective. Due to anatomical variations or after unsuccessful transarterial therapy, a direct surgical approach to the superior ophthalmic vein (SOV) may be necessary. CASE REPORTS: In two patients with acute ophthalmologic symptoms coil occlusion of the CCF was performed after palpebral incision and cannulation of the SOV. RESULTS: In both patients preparation of the SOV was performed successfully and without complications. After coil embolization of the CCF both patients had complete resolution of symptoms within several weeks. During a follow-up of 12 months there were no recurrences, but both patients exhibited moderate blepharoptosis. CONCLUSION: Embolization of CCF via a surgically created approach is an effective procedure in selected cases when standard interventional treatment is not possible.

Carotid-Cavernous Sinus Fistula↗

PubMed1999

[Diagnostic and therapeutic concepts of canine fossa abscess. Evaluation of a multicenter study of 55 German-speaking departments of oromaxillofacial surgery].

A possible complication of fossa canina infections is reactive thrombosis of the vena angularis, which can lead to cavernous sinus phlebothrombosis. According to the literature there are different opinions about the treatment protocol of fossa canina abscesses. Therefore a multicentre study was undertaken in which 55 departments of oral surgery were interviewed using a standardized questionnaire about their procedures. The basis of diagnosis consists of clinical examination (100%), antibiogram (77.1%) and radiography (97.1%). A total of 28.6% use additional imaging procedures. Sonography is used by 20.0% and is found to be helpful in the diagnosis of vena angularis thrombosis. The painful palpation of the medial angle of the eye is of major diagnostic importance (100%) although anatomic variations of the vena angularis have to be considered. Extraoral incisions are not used in most cases (25.7% in exceptional cases) as well as ligations of the vena angularis in case of thrombosis (8.6% in exceptional cases). There is an agreement in the use of antibiotics (elective administration in 14.3%, obligatory administration in 85.7%); 77.1% don't use heparin to treat thrombosis of the vena angularis. In heparin therapy risks such as bleeding complications and thrombocytopenia have to be considered.

Cavernous Sinus Thrombosis↗

PubMed2005

Gadolinium-enhanced versus time-of-flight magnetic resonance angiography: what is the benefit of contrast enhancement in evaluating carotid stenosis?

Accurate patient selection based on preoperative imaging is imperative to good risk reduction in patients undergoing carotid endarterectomy (CEA). The goal of this study was to assess the accuracy of gadolinium-enhanced magnetic resonance angiography (GE MRA) versus time-of-flight (TOF) MRA in the work-up of patients undergoing CEA. Patients undergoing CEA between 1999 and 2001 were identified from a prospectively maintained institutional database. GE or TOF MRA was obtained on extracranial carotid arteries (n = 319) in patients undergoing CEA. Stenosis on MRA images was graded as moderate (n = 76) or severe (n = 243) by an attending radiologist who was blind to duplex results. Duplex imaging was performed in an Intersocietal Commission for the Accreditation of Vascular Labs (ICAVL) accredited lab, and stenosis was stratified as moderate (50-79%, n = 76) or high (80-99%, n = 243) grade using University of Washington criteria. For each patient, the degree of stenosis as determined by MRA (GE versus TOF) was compared to percent stenosis on duplex. For moderate-grade lesions, GE MRA concurred with duplex in 11.1% (4/36), underestimated in 2.8% (1/36), and overestimated in 86.1% (31/36) of carotid arteries imaged. TOF MRA concurred with duplex in 35% (14/40), underestimated in 0% (0/40), and overestimated in 65% (26/40) of carotid arteries. High-grade lesions demonstrated improved concordance between MRA and duplex. For these lesions, GE MRA concurred with duplex in 95.6% (130/136) of carotid arteries imaged, never overestimated stenosis (0/136), and underestimated in 4.4% (6/136). TOF MRA concurred with duplex 96.3% (103/107), overestimated stenosis as an occlusion in 0.9% (1/107), and underestimated in 2.8% (3/107). In addition to neck visualization, the GE technique allowed simultaneous aortic arch imaging. This was accomplished in 79.1% (136/172) of all GE MRAs. Simultaneous aortic arch imaging was not technically feasible with TOF MRA. For moderate-grade lesions, both MR techniques are inaccurate predictors of degree of carotid stenosis and result in a significant overestimation of stenosis. Each technique demonstrates improved concordance with duplex ultrasound in the setting of severe carotid artery stenoses. The ability of GE MRA to simultaneously image the aortic arch and the neck may allow for detection of occult tandem lesions and other anatomic variations, which may be particularly important in preoperative planning for carotid artery stenting.

Carotid Stenosis↗

PubMed1998

Aneurysm of a common celiomesenteric trunk.

Aneurysm of the celiac and/or superior mesenteric arteries are uncommon, accounting for 10% of visceral artery aneurysms. Aneurysms involving a common celiomesenteric trunk are extremely rare. Up to now only two cases have been reported. In this report we describe a saccular aneurysm originating from the bifurcation of a common celiomesenteric trunk. Treatment consisted of resection followed by suture of the aneurysmal neck. This anatomic variation of the visceral arteries probably resulted from a defect in embryonic development suggesting that the aneurysm was congenital in origin. Other etiologies of aneurysms in this location are atherosclerosis, infection, inflammation, and arterial dystrophy. These lesions are almost always surgical indications requiring complete angiographic study of the visceral vasculature.

Aneurysm↗

PubMed2007

Embolization for a bleeding pelvic fracture in a patient with persistent sciatic artery.

Emergency embolization for a bleeding pelvic fracture was performed in a patient with persistent sciatic artery, a rare anatomic variation in which the internal iliac artery continues to the popliteal artery. Successful hemostasis was achieved without complications by means of selective catheterization into each branch of the internal iliac artery. Awareness of this unusual vascular anatomy is critically important to avoid serious complication of emergency embolization.

Angiography↗