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PubMedDate not supplied

[Critical analysis of the clinical and surgical importance of the variations in the origin of the sinoatrial node artery of the human heart].

There are several clinical controversies derived from the discrepancy on the description and relations of the coronary arteries in human hearts of either sex and in different races. OBJECTIVE--To study the clinical and surgical importance of the variations of the origin of the artery of the sinoatrial node in hearts of human individuals. MATERIAL AND METHOD--Normal hearts of cadavers of 100 individuals (31 females and 69 males), belonging to 24 Caucasians (whites) and 36 non-Caucasians (Negroes and Mulattoes), whose age varied ranged from 7 to 80 years, were studied. The coronary arteries were injected with gelatin mixed to a radiopaque substance (Cylatrast) and a red or blue pigment. RESULTS AND CONCLUSIONS--1) The artery of the sinoatrial node was originated more frequently from the right coronary artery (58%) than from the left. 2) When originated from the left coronary artery the artery of the sinoatrial node was more frequently a branch of the circumflex artery (30%) than from the trunk of the artery (12%). 3) No sexual or racial factor influenced the anatomical variations. 4) The most frequent arteries originating the artery of the sinoatrial node were the right anterior medial atrial artery and the left anterior medial atrial artery. 5) No cases of blood supply to the sinoatrial node were found originating neither from other arteries than the coronary arteries nor from both coronary arteries. 6) The distribution of the coronary arteries allows to understand the possible ischemic etiology of the sinusal node syndrome and permits to the surgeon a safe approach to cardiac disease.

Adolescent↗

PubMed1994

Surgical anatomy of the papilla of Vater and biliopancreatic ducts.

The present research was aimed at defining the surgical anatomy of the biliopancreatic ducts and of Oddi's sphincter. The numerous anatomic variations of the papilla, the millimetric distribution of its muscle fibres, and any morphological detail of clinical significance have been investigated. An integrated analysis of radiographic, tridimensional (casts), and histologic findings has been carried out in 49 of 64 autoptic bilio-duodenopancreatic specimens. Exact limits of the choledocus and Wirsung sphincters were defined. A consistent accumulation of circular muscle fibres could be seen, on the choledocus duct side, up to a mean distance of 13.6 mm from the papillary pore. However, more rarefied fibres were present up to 20.5 mm. Muscle fibres were seen to stop roughly on the pancreatic duct side at 7.3 mm from the papillary pore. The beginning of the sphincter was observed 2-3 mm above the papillary pore. There was no evidence suggesting the presence of upper, middle, and lower biliary sphincters. Five anatomic diversities of the Wirsung-choledocus confluence were found. The Y type was the most frequent (61.2%), followed by the U type (22.4%), V (14.3%), and II (2.1%). Santorini's duct with a normal papilla was present in 16 per cent of the cases. These data along with other interesting observations on antireflux mechanisms (Santorini's valves) and on the ductal space orientation appear to be useful guidelines for a physiopathological understanding of bilio-pancreatic diseases and for any therapeutic procedure on these structures.

Ampulla of Vater↗

PubMed1999

Movement dysfunction following repetitive hand opening and closing: anatomical analysis in Owl monkeys.

Repetitive strain injuries are thought to result from biomechanical stress and tissue microtrauma. The purpose of this study was to investigate the presence of local inflammation, scarring or anatomical variations of the flexor tendons and the median and ulnar nerves in four Owl monkeys behaviorally trained at a repetitive motor or sensory task. Three monkeys were trained to repetitively open and close a handpiece. The two monkeys that used rapid, stereotypical hand squeezing developed a task-specific movement dysfunction (one in 5 weeks and one in 24 weeks). The third monkey used a variable shoulder-pulling strategy and did not develop movement problems. The fourth monkey served as a control subject for the repetitive motor movements, trained on a repetitive sensory task, and did not develop a task-specific movement dysfunction. On dissection and histologic staining, there were no signs of active inflammation in the median nerve, the ulnar nerve, or the flexor tendons in any of the monkeys. However, the monkey that developed movement problems after 5 weeks of repetitive hand squeezing had an anatomical restriction of the flexor profundus tendon on the fourth digit of the trained side and the third digit of the untrained side. Reorganization of the representation of the hand on the contralateral somatosensory cortex (area 3b) was noted in the two monkeys that developed motor control problems and in the monkey performing the repetitive sensory task. These findings suggest that repetitive, stereotypical motor behaviors can lead to motor control problems without local signs of tendon or nerve inflammation. Preexisting anatomical restrictions may modify the time course for the development of movement dysfunction under conditions of stressful repetition. This animal model may simulate clinical focal hand dystonia (or occupational hand cramps) which can develop in human subjects who perform prolonged, repetitive, stereotypical movements.

Animals↗

PubMed2006

Ansa cervicalis as a variant of spinal accessory nerve plexus: a case report.

The ansa cervicalis is a neural loop in the neck formed by the union of two main nerve roots, namely superior and inferior roots, derived from ventral rami of the cervical nerves. With the expanding use of the ansa cervicalis for reinnervation procedures and the fact that it is located in the vicinity of major nerves and vessels of the neck, knowledge of the topography and morphology of this loop is quite necessary in the modern era. Any variation in the course, contributing roots or branching pattern of the ansa cervicalis, potentially alters and perhaps complicates the course of the procedures involving this nerve such as neurorrhaphy, skull base surgery, neck dissection, and anterior cervical spinal approach. Here, we present an unusual case of an ansa cervicalis encountered upon routine dissection of an adult male cadaver. In this case, the inferior root of the ansa cervicalis was formed by the joining of two rootlets, one originating from spinal accessory nerve and the other from a branch of the cervical plexus to the sternocleidomastoid muscle. The fibers traversing the branch of spinal accessory nerve were derived from the first segments of the cervical spinal cord. This case demonstrates a variant of the spinal accessory nerve plexus that contributed to the formation of the ansa cervicalis. Review of the literature was performed to reveal the possible clinical aspects of this anatomical variation.

Adult↗

PubMed2005

Transcranial Doppler sonography evaluation of anterior cerebral artery hypoplasia or aplasia.

BACKGROUND AND PURPOSE: Transcranial Doppler (TCD) sonography is useful to evaluate intracranial arteries, however, interpretation of the TCD results in anterior cerebral artery (ACA) is difficult because of hypoplasia or aplasia. We try to define useful TCD indices and cut-off values to determine the variations of ACA. METHODS: Consecutive patients who underwent TCD and magnetic resonance angiography (MRA) were included. Patients with cerebrovascular abnormality or inadequate temporal windows were excluded. ACA status was classified as normal (NL), hypoplasia (HP), and aplasia (AP) according to MRA. TCD indices of mean flow velocity (MFV), pulsatility index (PI), ACA/middle cerebral artery (MCA) flow velocity ratio (ACA/MCA FVR), and asymmetry index (AI) of ACA were blindly compared with MRA between three groups. RESULTS: Two hundred and forty-one patients were included, and 193 patients (80%) were classified as NL, 34 (14%) as HP and 14 (6%) as AP. MFV was significantly lower in HP and AP (p<0.001), however, PI and ACA/MCA FVR were not different. AI was significantly different between NL and HP (21.5% vs. 50.4%), NL and AP (21.5% vs. 105.2%) (p<0.001). CONCLUSIONS: MFV of ACA should be interpreted with caution for its frequent anatomical variations. AI is useful to differentiate hypoplasia and aplasia from normal ACA with optimal criteria.

Adult↗

PubMed2005

Use of medial arm skin as a free flap.

BACKGROUND: Free transfer of the medial arm flap has not gained popularity despite the hidden donor-site scar as well as the hairless and elastic skin. This may be because of variations in vascular anatomy, leading to confusion during dissection of the flap. METHODS: In five preserved cadaver arms, the vascular pattern of medial arm skin was examined. Twenty-two upper extremity angiograms were examined, and 12 free medial arm flaps were elevated for various defects in 12 patients. RESULTS: In cadaver and clinical dissections, the authors found that blood supply to the flap is multiple: from the superior ulnar collateral artery, the direct cutaneous artery, or both. A superficial brachial artery may also be present, which was observed in four angiograms and two clinical cases (15 percent). Dissections showed that the medial arm skin may be elevated based on the superficial brachial artery, direct cutaneous artery, or superior ulnar collateral artery. A neurosensory flap may be obtained by including the medial brachial cutaneous nerve of the arm. CONCLUSIONS: A medial arm free flap is a plausible reconstructive option with good knowledge of the anatomical variations, as the defect on the medial arm is cosmetically more acceptable and has a better color match for head and neck reconstructions.

Adult↗

PubMed2004

Preoperative color Doppler assessment in planning of anterolateral thigh flaps.

The anterolateral thigh flap has many advantages, but it has not yet achieved widespread use because the perforators exhibit considerable anatomical variation and their locations are difficult to predict preoperatively. The authors performed a prospective study to investigate whether acoustic Doppler flowmetry and color Doppler ultrasonography were helpful for preoperative localization of the perforators in anterolateral thigh flaps. Ten patients scheduled for anterolateral thigh flap surgery were examined preoperatively with both acoustic Doppler flowmetry and color Doppler ultrasonography, and all points where the perforators seemed to penetrate the fascia lata were mapped. The actual perforating points were identified intraoperatively and were compared with the preoperatively mapped points. Fifteen perforators were detected in 10 patients. The concordance rate with acoustic Doppler flowmetry was 40 percent (95 percent confidence interval, 15 to 68 percent; p = 0.05). In contrast, the concordance rate with color Doppler ultrasonography was 100 percent (95 percent confidence interval, 81 to 100 percent; p = 0.05). Color Doppler examination was significantly more accurate than acoustic Doppler examination (determined by the binomial test; p < 0.0014). Three-dimensional anatomical information around the perforators was further useful in elevating flaps. The authors conclude that color Doppler examination can accurately identify the perforators and is useful for planning in anterolateral thigh flap surgery, whereas acoustic Doppler examination is unreliable.

Adult↗

PubMedDate not supplied

Non-recurrent inferior laryngeal nerve.

Surgical damage to the inferior laryngeal nerve is one of the most feared complications of thyroid surgery. Prevention of surgical injuries requires systematic, early exposure of the inferior laryngeal nerve. A detailed knowledge of anatomical variations is necessary. Non-recurrent inferior laryngeal nerve is a rare anomaly on the right side and is exceptional on the left. Whereas the typical course of the inferior laryngeal nerve is due to the embryological development of the aortic arch and supra-aortic vessels, non-recurrence is associated with a vascular anomaly such as a right retro-oesophageal subclavian artery. The nervous anomaly on the left side is possible only with the occurrence of cardiac dextroposition (situs viscerum inversus) and a left retro-oesophageal subclavian artery. The situation is more dangerous when a non-recurrent branch of the inferior laryngeal nerve is associated with a recurrent branch. This anomaly does not appear to be associated with a vascular anomaly in all cases. The authors describe three cases of right non-recurrent inferior laryngeal nerve observed and one recent case of combined non-recurrent and recurrent nerve, highlighting the anatomical and surgical features of this anomaly.

Adult↗

PubMed2005

Posterior cruciate ligament recess and normal posterior capsular insertional anatomy: MR imaging of cadaveric knees.

PURPOSE: To analyze the normal pattern of fluid accumulation adjacent to the posterior cruciate ligament and anatomic variations of joint capsule insertion sites in the posterosuperior corner of the human knee by using magnetic resonance (MR) imaging in cadaveric specimens. MATERIALS AND METHODS: Fourteen fresh cadaveric knees (obtained and used according to institutional guidelines, with informed consent from relatives of the deceased) from 11 men and three women (six left knees, eight right knees; age range, 70-82 years at time of death; mean age, 76 years +/- 4.4 [standard deviation]) were studied with high-spatial-resolution MR imaging performed before and after intraarticular injection of 35-45 mL gadopentetate dimeglumine. MR images were evaluated by two readers in consensus, with emphasis on location of fluid posterior to the posterior cruciate ligament, communication of that fluid with the medial or lateral compartment of the knee, and the relation of fluid to surrounding structures. Readers also were asked to measure, in the sagittal plane, the distance between the posterior capsular insertion sites and the femoral physeal scar. For anatomic analysis, cadaveric specimens were sectioned in 3-mm-thick slices in the sagittal plane that approximated the sections acquired at MR imaging. RESULTS: In all 14 cadaveric specimens, MR arthrographic images showed a fluid collection behind the posterior cruciate ligament (in the posterior cruciate ligament recess), a finding not evident on images obtained prior to contrast material injection. The recess was distended during flexion, and it communicated only with the medial femorotibial compartment in all cases. Posterior to the posterior cruciate ligament recess, a fat pad was observed in all specimens. Incomplete joint capsule was seen behind the fat pad in seven specimens. Joint capsule insertion was at the level of the femoral physeal scar or between it and a point 15 mm above it. CONCLUSION: The posterior cruciate ligament recess has specific characteristics that allow its identification: communication with the medial compartment of the knee and absence of the adjacent joint capsule.

Aged↗

PubMed1995

CT and MR imaging of the buccal space and buccal space masses.

The authors describe the normal variations in the buccal space and present the range of buccal space pathologic conditions seen on computed tomographic (CT) and magnetic resonance (MR) images. In a series of 50 patients studied with CT and 30 with MR imaging, the visualization and measurement of the normal facial expression and buccinator muscles, parotidomasseteric fascia, parotid duct, accessory parotid tissue, and facial neurovascular bundle were statistically equivalent. The size of the buccal fat pad was statistically the same from side to side within a given patient. Normal lymph nodes were rarely discernible from the facial neurovascular bundles. In a series of 26 patients with unsuspected buccal space masses, salivary gland tumors were the most common masses. Less frequently, benign lesions (eg, hemangioma and dilated parotid ducts) and soft-tissue malignancies (eg, sarcoma) manifested as buccal space masses. Occasionally, a cheek mass of uncertain cause proved to be lymphadenopathy; however, adenopathy is more commonly associated with clinically evident, deeply infiltrating facial neoplasms. Knowledge of the anatomic variations and expected abnormalities of the buccal space is useful for the radiologist interpreting facial CT or MR images.

Adult↗

PubMed1998

NADPH-diaphorase positive myenteric neurons in the ileum of guinea-pig, rat, rabbit and cat: a comparative study.

The nitrergic system of the ileal myenteric plexus of four mammalian species was studied by means of NADPH diaphorase histochemistry which in aldehyde-fixed tissue stains only those cells that contain the constitutive, calcium-dependent nitrogen monoxide synthase isoenzyme. Since previous studies assumed minor species-specific anatomical variations, we sought similarities and differences in the nitrergic innervation pattern of the ileal musculature. In rat and guinea-pig, the ratio of nitrergic cells slightly exceeds 20%, in rabbit it is close to this number (16%), and it is lowest in cat (about 10%). The nitrergic neurons target the circular muscle layer in all investigated species where they participate in inhibitory motoric transmission. Apart from this, some elements of the sensory innervation of the circular musculature may derive from nitrergic neurons in rat and rabbit. The tertiary plexus (longitudinal muscles) is strongly supplied by NADPH diaphorase positive fibres in rat, moderately in guinea-pig and cat and not at all in rabbit. The rest of the nitrergic neurons may serve as inhibitory interneurons and control other (probably excitatory motor) neurons in the myenteric plexus. We conclude that the diverse physiological and pharmacological properties of the nitrergic system described in the small intestine in different species can be connected with the anatomical heterogeneity of its elements.

Animals↗

PubMed2002

Flexible tubular replicas of abdominal aortic aneurysms.

The aim of this study was to manufacture life-size, flexible, tubular replicas of human abdominal aortic aneurysms and the associated vasculature, suitable for use in a training simulator for endovascular procedures. Selective laser sintering was used to create a geometrically correct master model for each of ten anatomical variations. The masters were used to generate flexible latex replicas. The use of the replicas in the training simulator was demonstrated. In total ten silicone rubber models were produced. When connected into the training simulator and perfused at arterial pressure it was possible to deploy an endovascular stent under fluoroscopic control and to perform angiography. The study has shown that conventional rapid prototyping technology can be used to manufacture flexible, radiolucent replicas which provide a realistic training environment for endovascular procedures.

Angiography, Digital Subtraction↗

PubMed2000

Factors associated with thoracic spinal cord injury, lesion level and rotator cuff disorders.

BACKGROUND: The study was concerned with the secondary functional compromise persons with long-term paraplegia contend with, that has been shown to be associated with wheelchair use. Of particular interest was the relationship between the level of thoracic spinal cord injury (SCI) and factors predisposing to rotator cuff disorders (RCD), one of the most common upper extremity musculoskeletal complications linked with long-term SCI. Disorders of these peri-articular structures have previously been associated with impaired trunk postural control and abnormal muscle strength ratios in both able-bodied groups and in paraplegic athletes. Despite their neurologically intact shoulder joint musculature, high-level and low-level paraplegics have different degrees of trunk and pelvic stability available to them during activities of daily living (ADL). This fundamental functional anatomical difference between high-level and low-level paraplegics had not previously been related to the diagnosis of RCD in a non-athletic long-term paraplegic population. METHODS: A descriptive cross sectional study was undertaken to demonstrate the differences in the prevalence of clinically diagnosed RCD in a high-level (n=22) and a low-level (n=20) group of persons with long-term paraplegia. Any perceived differences were then related to the functional anatomical variations between the two groups. Inferences were made based on factors predisposing to RCD known to exist among both able-bodied and paraplegic athletes. The 42 subjects completed the Wheelchair User's Shoulder Pain Index (WUSPI) to establish the presence or absence of shoulder pain and the Musculoskeletal Function Assessment (MFA) instrument to determine differences in functional ability and perceived degree of difficulty within five categories of ADL. Each participant underwent a clinical examination using validated provocative clinical tests and isometric muscle strength ratio testing. RESULTS: There was a higher prevalence of RCD in the high-level group (P=0.009) which correlated with decreased trunk control (P=0.009). Differences in ability to perform functional tasks were not shown to be greater in the high-level group, although there was a higher degree of perceived difficulty in ADL. Muscle strength imbalances between the shoulder adductors and abductors were shown to be greater in the high-level group. CONCLUSIONS: The results of this study suggest that the functional anatomical differences that exist within paraplegia contribute to the propensity of high-level paraplegic persons to suffer from RCD. These findings send a clear message to service-providers that greater acknowledgement of the differences in trunk postural control specific to the level of thoracic SCI is required. This may have implications for the prescription of wheelchairs, assistive devices and instruction for alternative ADL techniques to this specific population.

Adult↗

PubMed1994

[The anatomy of the bronchial arteries--their imaging with spiral CT].

UNLABELLED: The purpose of our study was to evaluate the capability of spiral CT in detecting bronchial arteries and in classifying their anatomic variations. PATIENTS AND METHODS: In 43 patients with different diseases routine spiral CTs of the chest were performed and evaluated retrospectively. Spiral CT was started with a delay of 30 seconds after contrast material application. RESULTS: In 43 patients a total of 67 bronchial arteries were detected: 31 right, 35 left and one common trunk. 26 right bronchial arteries originated medially, 5 anteriorly from the descending aorta, 7 of them together with an intercostal artery. 25 right bronchial arteries passed dorsally, 6 ventrally to the oesophagus. On the left, all 35 bronchial arteries originated from the anterior aorta: 12 led ventrally through the aorticopulmonary window to the ventral wall of the main bronchus, 14 were directed caudally to the cranial and 9 laterally to the posterior aspect of the main bronchus. The discernible length varied between 15 and 90 mm on the right, and between 10 and 37 mm on the left side. Only in two cases did the proximal diameter measure more than 2 mm. CONCLUSION: Spiral CT offers the possibility to classify the anatomic course and pathologic changes of the bronchial arteries.

Adolescent↗

PubMed1989

The management of differentiated thyroid cancer in Europe in 1988. Results of an international survey.

In order to know how thyroid nodules and differentiated thyroid cancers are investigated and treated in 1988, an international inquiry was performed by mean of a questionnaire based on a well-defined case report of a 35-year-old female with a solitary small thyroid nodule. Clinicians were asked to indicate their diagnostic and therapeutic approaches to the reported case and to some variations. Analysis of the 157 responses from thyroid experts showed that three in vitro tests (sensitive-TSH, free T4 and total T4) and three in vivo tests (99mTc or radioiodide scintiscan, fine needle aspiration and ultrasonography) were performed most frequently. In the case of a solid and cold nodule and in the absence of fine needle aspiration results, 19% of respondents advocated suppressive therapy and 81% surgery. In the same clinical case, but whom fine needle aspiration had been performed and cytology was benign, surgery was advocated by 24%, suppressive therapy by 48% and a regular follow-up without treatment by 28% of respondents. When surgery was performed and the diagnosis was a differentiated thyroid cancer, (near) total thyroidectomy was more frequently chosen than partial thyroidectomy in both papillary (60 and 40%, respectively, of respondents) and follicular (74 and 26%, respectively, of respondents) cancers; 80% of clinicians did not change their surgical technique in relation to histological type of the tumour. Total thyroidectomy was more often recommended in most of the clinical or anatomical variations compared with the basic case report. Pre- or postoperative hormonal therapy was initiated with L-T4 and TSH suppression was controlled by sensitive-TSH and thyroglobulin determinations. After total thyroidectomy, 131I was used with similar modalities for papillary and follicular cancers to ablate a thyroid remnant.

Adult↗

PubMed2006

Variation of mesorectal volume with abdominal fat volume in patients with rectal carcinoma: assessment with MRI.

The purpose of this study was to assess the variability in the volume of the mesorectum in patients with rectal carcinoma. A retrospective review was made of pelvic MRI studies in 30 patients (mean age 64 years, range 34-88 years, 18M:12F) with histologically proven rectal carcinomas that were confined to the mesorectum. The outer low signal margin of the mesorectum was traced, over at least 10 consecutive 10 mm contiguous slices, until its disappearance. The visceral fascial compartment, body cross-sectional area and body mass index were measured, on a solitary slice, at the level of the L5/S1 disc. Linear regression was calculated for independent determinants of the mesorectal volume. Mean mesorectal volume in males was 227.5 cm3 (95%CI 191.6-263.4), and in females was 157.5 cm3 (95%CI 129.3-185.7). The difference in mesorectal volume between men and women was statistically significant (p<0.001). Mean visceral compartment area in males was 18.4 cm2 (95%CI 16.3-20.5) and in females was 14.6 cm2 (95%CI 12.8-16.4). Visceral compartment area correlated with mesorectal area and volume in females (p<0.05), and extremely well in males (p<0.005). Body cross-sectional area, body mass index and age did not correlate with mesorectal size. The correlation of visceral compartment area with mesorectal volume and mean area suggests that the mesorectum is determined in a similar way to other body fat compartments, with a similar anatomical variation. This significant variation in size and volume may have an important prognostic implication in patients with rectal carcinoma. This volume can be measured and reported on pre-operative MRI scanning and may be communicated to surgeons and radiotherapists.

Abdominal Fat↗

PubMed2004

A post-processing/region of interest (ROI) method for discriminating patterns of activity in statistical maps of fMRI data.

To combine functional neuroimaging studies across subjects, anatomical and functional data are typically either transformed to a common space or averaged across regions of interest (ROIs). However, if there are (1) anatomical variations within the subject pool (as in clinical or aging populations), (2) non-Gaussian distributions of task-related activity within a typical ROI or, (3) more ROIs than subjects, neither spatial transformation of the data to a common space nor averaging across all subjects' ROIs is suitable for standard discriminant analysis. To solve these problems, we describe a post-processing method that uses voxel-based statistics representing task-related activity (pooled within ROIs) to establish combinations of ROIs that maximally differentiate tasks across all subjects. The method involves randomized resampling from multiple ROIs within each subject, multivariate linear discriminant analysis across all subjects and validation with bootstrapping techniques. When applied to experimental data from healthy subjects performing two motor tasks, the method detected some brain regions, including the supplementary motor area (SMA), that participated in a distributed network differentially active between tasks. However there was not a significant difference in SMA activity when this region was examined in isolation. We suggest this method is a practical means to combine voxel-based statistics within anatomically defined ROIs across subjects.

Brain↗

PubMed2006

Transoesophageal echocardiographic evaluation of pulmonary vein anatomy in patients undergoing ostial radiofrequency catheter ablation for atrial fibrillation: a comparison with magnetic resonance angiography.

OBJECTIVE: A detailed definition of pulmonary vein (PV) anatomy is of great importance in patients undergoing radiofrequency catheter ablation for atrial fibrillation. In fact, it is known that variations in the number and anatomy of the PV ostia are more frequent than thought. The aim of this study was to assess the usefulness of transoesophageal echocardiography (TOE) in defining the exact PV anatomy by comparing it with magnetic resonance angiography (MRA), which is proven to be very accurate. METHODS: Forty-five consecutive patients (39 male, 6 female, mean age 50 + or - 6 years) affected by drug-refractory atrial fibrillation underwent radiofrequency catheter ablation. They were all studied with MRA and then with TOE in order to exclude intra-atrial thrombi and to assess PV anatomy. RESULTS: TOE visualised the superior PVs in 100% of cases and the right and left inferior PVs in 98% and 94% of cases, respectively. Only 19 patients (42%) showed typical PV anatomy, with two left and two right distinct PV ostia. In 14 patients (31%), one or two intermediate right PVs and in 12 patients (27%) a common left trunk were detected. The concordance with MRA was high (95%). CONCLUSIONS: TOE is accurate in assessing PV anatomy and in showing anatomic variations in the PV ostia compared with MRA. Anomalous pulmonary venous drainage is more frequent than expected. TOE can provide functional Doppler information, thus being particularly useful in the follow-up after radiofrequency catheter ablation.

Adult↗