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Anastomosis between both hypoglossal nerves in a 30 mm human embryo.

In this paper we present the first description of an anastomosis between both hypoglossal nerves during the embryonic period, a very uncommon anatomical variation. This was observed in a 30 mm crown-rump (C-R) length human embryo (Carnegie stage 23) from the Bellaterra Collection (Prof. Doménech Mateu), stained for nerve fibers. The anastomosis consisted of a large diameter trunk (36.7 microns) situated in front of and slightly below the hyoid cartilage, and clearly distinguishable from the anastomosis found in adults, which has a very fine diameter and is located in the suprahyoid region.

Embryo, Mammalian↗

Renal allograft artery stenosis: results of medical treatment and intervention. A retrospective analysis.

In a retrospective analysis of 1165 renal transplantations in our center, 65 cases of renal allograft artery stenosis were diagnosed angiographically (prevalence 5.5%). Hypertension was present in all cases; a bruit over the allograft and an increase in serum creatinine level were additional reasons for angiography. Shortly after diagnosis of the stenosis, two patients died and two others lost their grafts due to thrombosis. In 24 patients the decision was made not to correct the stenosis. One of these grafts was lost because the stenosis could not be corrected. Medical management of hypertension in these patients resulted in a decrease in diastolic blood pressure from 109 +/- 22 to 96 +/- 12 mm Hg (P < 0.01) 3 months after diagnosis with the use of almost twice as many antihypertensive drugs as at the time of diagnosis (P < 0.01). The stenosis was corrected if the angiography showed it to be so severe that it jeopardized renal allograft function or caused uncontrollable hypertension. Only three of nine percutaneous transluminal angioplasty (PTA) procedures resulted in a definitive correction of the stenosis. Surgical intervention was performed in 30 patients, including two patients whose PTAs had proved unsuccessful. Surgery led to graft loss due to thrombosis in 6 of 30 operations (20%), whereas restenosis occurred twice (7%). In three other cases (10%), the correction was not successful due to local anatomical variations or concomitant rejection.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗

The double fat fluid level: lipohemarthrosis of the knee associated with suprapatellar plica synovialis.

Lipohemarthrosis is a frequent occurrence following intrarticular fracture. The contour of the fat and blood interface in the knee joint is dependent upon suprapatellar anatomy. Anatomic variations of the suprapatellar joint space can significantly alter the radiographic appearance of lipohemarthrosis. Three cases are presented in which a double fat-fluid level was identified, due to presence of a well developed suprapatellar plica synovialis. Recognition of the variable appearance of lipohemarthrosis of the knee is important to avoid overlooking this finding in the traumatized patient.

Adult↗

[C5 collaterals of the internal carotid siphon: embryology, angiographic anatomical correlations, pathological radio-anatomy (author's transl)].

Since Parkinson's original description, the C5 collaterals are always presented as originating from a common trunk (meningo-hypophyseal). This is the least frequent anatomical variation. In fact, the posterior (C5) group of collaterals corresponds to the remnant of two transient embryonic vessels (primitive maxillary and trigeminal arteries), branches of which will give rise to the two main groups of collaterals originating from this area: medially, the inferior hypophyseal and the medial clival arteries; laterally, the basal tentorial and lateral clival arteries, which are constantly anastomosed with the ascending pharyngeal artery. Only in some cases (10%) do these two groups arise in common from the C5 carotid siphon. Apart from these branches the so-called Bernasconi's artery may originate from eight different pedicles, the C5 siphon representing only one of them.

Carotid Artery, Internal↗

[Consequences of a high-placed jugular bulb for the inferior ventilation pathway of the middle ear].

The evaluation and the correlation between the healthy and inflamed system of the mucosal folds of the middle ear demonstrate that there is a second "bottle neck" of the aeration pathways (the first being the Eustachian tube) in the region of the tympanic diaphragm with the tympanic isthmi - anterior and posterior -, the latter is more important for the ventilation of the epitympanum and antrum. Anatomical variations in this lower air-pathway as a high placed jugular bulb into the middle ear cavity endanger of course the undisturbed ventilation of the epitympanum and antrum in case of the infected and swollen mucosa and its folds.

Ear, Middle↗

The anatomy of the hepatoduodenal ligament in laparoscopic sonography.

Laparoscopic sonography was introduced at our institution in April 1991. It is presently being tested as an alternative to peroperative cholangiography as far as the visualization of the structures of the hepatoduodenal ligament--particularly the extrahepatic bile ducts--during laparoscopic cholecystectomy are concerned. So far, 75 patients have been examined with both modalities. The structures of the hepatoduodenal ligament could be seen sonographically in all patients, while in five patients, the cholangiography had to be aborted for technical reasons. Eleven patients (15%) had anatomical variations of the bile ducts. Nine of these were diagnosed sonographically. A duodenal diverticulum and a long common channel of common bile duct and pancreatic duct were seen only on cholangiography. Variations of the hepatic arteries were found in 15 patients (20%). We conclude that intraoperative laparoscopic sonography is a reliable tool for the visualization of the structures of the hepatoduodenal ligament. This new technique might replace peroperative cholangiography in the future.

Adolescent↗

Protrusion of the optic nerve into the ethmoid and sphenoid sinus: prospective study of 150 CT studies.

Damage to the optic nerve is a serious complication of intranasal sinus surgery. Protrusion of the optic canal into the sphenoid sinus is a major risk factor. In this prospective study of 150 CT studies, we found this anatomical variation in 8% of cases. It was consistently associated with pneumatisation of the ipsilateral anterior or clinoid process. Protrusion of the optic nerve into the posterior ethmoid cells was never observed. CT is a useful part of the preoperative investigation of patients undergoing intranasal sinus surgery. Axial and coronal images obtained or by direct acquisition by reconstructions are necessary to show the position of the optic nerve.

Adult↗

[The effect of non-coplanarity of the horizontal semicircular canals on experimental vestibular testing (author's transl)].

It is generally accepted that the horizontal semicircular canals are coplanar. One hundred three elliptic tomograms of human temporal bones have been evaluated for their planar relationship. The median was 180 degrees. However, the values varied between 160 degrees and 223 degrees. Differences of more than +/- 10 degrees were found in 31% of all cases. These anatomic variations are important for experimental vestibular testing, if, e.g., vestibulo-spin al effects result in a deviation or a torsion. With rotatory testing, stimulus intensity is a function of head inclination in relation to the stimulus plane. Non-coplanarity associated with head inclination results in asymmetric stimulus strength. With thermic testing, the effective stimulus is a function of the angle between temperature gradient across the canal and gravitation. Besides deviations from the perpendicular plane, rotations within this plane, according to Brünings "Schiefoptimumstellung", additionally cause asymmetrical errors.

Ear, Inner↗

Unusual renal distortion and displacement due to the spleen.

Occasional normal anatomic variations may produce radiographic appearances that closely simulate disease and visceral enlargement may cause unusual displacements of adjacent organs. Two cases are reported in whom prominent splenic lobulation caused flattening of the upper pole of the left kidney. The appearance simulated that produced by a supra-renal mass. The value of CT in differentiating this normal variation from disease is discussed. A third patient in whom massive splenomegaly caused upward displacement of the left kidney is also reported. The literature concerning visceral relationships in the left upper quadrant and the normal variations that simulate disease is reviewed.

Adolescent↗

The pharmacokinetics of the intravenous steroid anesthetic alphaxalone in the isolated perfused rat lung.

We have examined four mathematical systems modeling the transit of the steroid anesthetic alphaxalone (3 alpha-hydroxy-5 alpha-pregnane-11,20-dione) through the lung. Using the isolated rat lung perfused with a plasma substitute containing 14C-alphaxalone and 3H-dextran, we have obtained results that are incompatible with models involving (a) anatomical variations in the microcirculation, (b) high solubility, or (c) specific binding. We develop a stochastic model of a physical process analogous to the sequence of events that takes place in a chromatography column. This model closely fits the experimental data and predicts a peak effluent concentration of alphaxalone that may occur after washout with several exclusion volumes. It represents a delay with the pulmonary compartment that may explain a difference in induction times observed between various intravenous anesthetic agents.

Anesthetics↗

[Surgical papillotomy, endoscopic-manometric and clinical results (author's transl)].

4--9 years after transduodenal papillotomy an endoscopic-manometric and clinical control of the surgical result was done in 49 patients. The pressure difference of common bile duct and duodenum was of great interest. There existed a correlation between the pressure difference and other parameters so far, as air was frequently seen in those patients without pressure gradient between common bile duct and duodenum. Pathological activity of gamma-GT and a decrease of Prothrombine-time was found after a high pressure difference. It may be possible that anatomical variations of the biliary system and the duodenum have some importance for the formation of stones.

Ampulla of Vater↗

Ductoplasty for an aberrant hepatic duct in a choledochal cyst.

The confluence of the right and left hepatic ducts at the hepatic hilum frequently shows normal anatomic variations. Choledochal cysts (CC) are also accompanied by similar variations, and devices for free drainage of bile are occasionally required in biliary reconstruction. We present a CC that had an aberrant posterior branch of the right hepatic duct draining into the distal common hepatic duct. A capacious hepaticoduodenostomy at the hilum was performed after joining the hilar and aberrant ducts.

Child, Preschool↗

Anomalies of the P1 segment of the posterior cerebral artery: early bifurcation or duplication, fenestration, common trunk with the superior cerebellar artery.

In a series of anatomical dissections on 100 fixed human brains, 3% of anomalies of the precommunicating segment of the posterior cerebral artery (P1) were found, among which a case of duplication of the P1 segment. This finding is very unusual and it is much rarer than the many other anatomical patterns reported in the circle of Willis. It is to be considered a very early bifurcation, as reported at the middle cerebral artery level. Another two unusual anatomical patterns were found. One was a large fenestration of the P1 segment, which is rather frequent in the vertebrobasilar system. The other was a bilateral common trunk between the posterior cerebral artery and the superior cerebellar artery, which represents a rare anatomical variation. The existence of such "anomalies" can be explained by the embryological development of the region. Their pathogenic and neurosurgical implications are discussed in the light of the literature.

Arteries↗

Microsurgical anatomy around the origin of the ophthalmic artery with reference to contralateral pterional surgical approach to the carotid-ophthalmic aneurysm.

The supraclinoid segments of the internal carotid artery (ICA) and their surrounding structures were examined under magnification in 25 adult cadavers. Attention was paid to anatomical variations and relationships concerning ipsilateral and contralateral pterional microsurgical approaches to these regions, especially to the origin of the ophthalmic artery. Eighty-four percent of the ophthalmic arteries arose from the supraclinoid segment of the ICA. In the ipsilateral pterional approach, mobilization of the ipsilateral optic nerve was required to see the origin of the ipsilateral ophthalmic artery and the medial aspect of the proximal portion of the supraclinoid segment of the ICA. In the contralateral pterional approach, on the other hand, these areas on the contralateral side could be identified under the optic nerve with minimal or without retraction of the contralateral optic nerve. This was because 71% of the ophthalmic arteries arose from the supero-medial aspect of the ICA, and because there was nothing to intercept the view of the medial aspect of the ICA under the optic nerve. This study supports the usefulness of the contralateral pterional approach to the origin of the ophthalmic artery and the medial aspect of the supraclinoid segment of the ICA. This approach could be useful in certain cases of carotid-ophthalmic aneurysm. The authors' experience with the contralateral pterional approach to carotid-ophthalmic aneurysms is also described.

Carotid Artery, Internal↗

Hyperparathyoidism: influence of glomerular filtration rate on urinary excretion of cyclic AMP.

Urinary cyclic AMP excretion per 24 h or per g creatinine in primary hyperparathyroidism (1 degrees HPT) has been evaluated by several authors with conflicting results. In 50 patients with 1 degrees HPT, 25 patients with secondary (2 degrees) HPT and 35 healthy control persons we determined urinary cyclic AMP per 24 h or per g creatinine. These parameters did not satisfactorily discriminate patients from controls, especially when glomerular filtration rate (GFR) as determined by creatinine clearance was reduced. Since urinary cyclic AMP is derived from plasma by glomerular filtration and from kidney by tubular production-the amount of tubules is reflected by GFR-the cyclic nucleotide was related to GFR. In controls urinary cyclic AMP correlated better with GFR than with creatinine excretion. Additionally, in 45 of 50 patients with 1 degrees HPT and in all with 2 degrees HPT, urinary cyclic AMP/GFR was raised. In 1 degrees HPT serum levels of parathyroid hormone correlated closer with urinary cyclic AMP/GFR than with urinary cyclic AMP/g creatinine. The ratio cyclic AMP/GFR decreased to normal or subnormal values after removal of adenomatous or hyperplastic glands in 1 degrees HPT and during infusion of calcium in 2 degrees HPT. In 50 patients with renal lithiasis caused by diseases other than 1 degrees HPT (anatomical variations, pyelonephritis, immobilization after tetraplegia) the ratio cyclic AMP/GFR was not raised. Urinary cyclic AMP/GFR, therefore, reflects parathyroid hormone excess more reliably than cyclic AMP/g creatinine.

Adolescent↗

The papillary muscles of the left ventricle and the cardiac segments.

The relationship between the arterial anatomicosurgical segments and the papillary muscles of the left ventricle was investigated in 38 human hearts of adult individuals of both sexes. The specimens were studied after (a) vinyl acetate injection and corrosion (28 hearts) or (b) formaldehyde fixation (10 hearts). In 4 of the corrosion casts, the cardiac chambers were not filled with the plastic substance and, prior to corrosion, the position of the papillary muscles was marked with threads or pins. The anterior papillary muscle was related to the (a) anterior interventricular segment (I SV); (b) lateral (II SV); and (c) left marginal segment (III SV). The medical portion of the anterior papillary muscle is supplied by the artery of the I SV whereas the lateral portion is supplied by the artery of the II or III SV. The posterior papillary muscle was related to the (a) anterior interventricular segment (I SV); (b) left marginal (III SV); (c) posterior interventricular segment (III DV) and (d) posterior ventricular (IV SV). As a rule, the papillary muscles are supplied by more than one segmental artery, therefore, anatomical variations may play an important role in functional alterations produced by ischemic lesions of the myocardium.

Adult↗

Microsurgical anatomy of the human ophthalmic artery: a mesoscopic study of its origin, course and collateral branches.

In the present paper we have studied the gross (mesoscopic) anatomy of the ophthalmic a. in humans, using magnification by microsurgical systems to obtain data on the origin and course of this artery and its main collateral branches. Comparison of our results with previous reports indicates that, although the anatomical variations of the vascular system are well known, some patterns of frequency may be emphasised. Thus, the ophthalmic a. was usually found as a collateral branch of the internal carotid a., although other origins were also found. The ophthalmic a., once inside the orbit, followed a course above the optic nerve in most cases. All the collateral branches of the ophthalmic a., with the exception of the muscular branches, showed great constancy.

Adult↗