Progress of fundamental research in Wilms'' tumor

The sectional anatomy of the pelvic floor was studied in plastinated sections of adult pelves by computed tomography and by magnetic resonance imaging. In sectional anatomy, the levator ani is composed of three portions that can be clearly distinguished by their planes of cleavage and by the course of their fiber bundles. No muscular connections are found between the levator ani portions and the pelvic organs. The fascia of the levator ani in always interposed between the muscle and the pelvic organs. The sectional anatomy of the sphincter ani externus reveals a subdivision into a subcutaneous and a deep portion. Although the puborectalis portion of the levator ani and the deep portion of the sphincter ani externus are more or less continuous, in sectional anatomy they can be distinguished due to their different origins and attachments.     

Variability of the midfacial muscles: analysis of 50 hemifacial cadaver dissections

The region of the midface represents a challenging area to both reconstructive and aesthetic surgeons. An anatomic study was performed that attempted to identify patterns and variations of the muscular anatomy. The goals of this study were twofold: to identify patterns and variability of the midfacial muscles that might impact on reconstructive efforts and to attempt to correlate this anatomy with features of the overlying soft tissues, specifically the nasolabial crease. Fifty hemifacial cadaver dissections were performed. The information collected was assembled into a large data base, and statistical significance was analyzed using Fisher's exact probability test. Results demonstrated that, although a great degree of variability exists with respect to the midfacial muscles, seven distinct patterns of these muscles did emerge. The most common pattern was the presence of a levator alae nasi, levator labii superioris, and zygomaticus major, which occurred in 44 percent of specimens. Specimens that possessed a risorius, zygomaticus minor, or both, were relatively uncommon. The consistent presence of the levators suggests adding a superior vector to recreate a smile in facial reanimation surgery. Two important anatomic variations were noted. A bifid zygomaticus major was found to be present in 34 percent of individuals. Because the inferior bundle had a dermocutaneous insertion, this anomaly may represent the anatomic correlate of a cheek "dimple." A second anomaly noted was the lateral cheek crease, which appeared to be associated with a cutaneous attachment from the underlying platysma muscle. However, no correlation could be found for facial muscle pattern and the overlying nasolabial crease structure. This lack of correlation may indicate that the facial muscles alone do not dictate the structure of the nasolabial crease and that other dynamic factors are involved in determining this feature of the aging face.     

Evaluation of levator muscle integrity in ptosis with levator force measurement

PURPOSE: To determine the efficacy of the force the levator muscle can generate as a diagnostic tool for ascertaining the cause of ptosis. METHODS: A total of 187 patients with ptosis were evaluated clinically, their levator force was measured, and each ptotic eyelid subsequently had surgical correction. At each step, patients received a diagnosis of congenital or acquired (history- dependent) aponeurotic, myogenic, neurogenic, or mechanical ptosis. To measure the levator force, a clamp placed on the upper eyelid lashes was attached to a force transducer. The maximum force generated on upgaze was recorded as the levator force. Data from healthy subjects were used to determine whether each levator muscle of the ptotic eyelids produced normal or less than normal force. The correct diagnosis was considered to be the diagnosis based on the findings at the time of surgery. The diagnosis of each patient with ptosis determined by eyelid excursion, eyelid excursion plus examination, levator force, and the levator force plus examination results were compared with the correct diagnosis. RESULTS: Eyelid excursion predicted the correct diagnosis 78.2% of the time. When eyelid excursion was combined with the examination results, the diagnosis was correct 84.0% of the time. Levator force predicted the correct diagnosis 95.2% of the time. When levator force was combined with the examination, the diagnosis was correct 97.9% of the time. CONCLUSION: Diagnosis of the cause of ptosis based on levator force measurement is significantly more accurate than when the diagnosis is based on eyelid excursion, even when information obtained on examination also is considered. Levator force measurement should be an integral part of ptosis evaluation.     

Startle responses measured in muscles innervated by facial and trigeminal nerves show common modulation.

Electromyographic (EMG) potentials of several head muscles were recorded simultaneously in freely moving rats with chronically implanted electrodes. The startle responses of m. temporalis, m. levator auris, and m. levator labii superior were compared. All muscles showed a parallel decrease in latency and an increase in response elicitability and amplitude with an increase in stimulus intensity. A significant latency difference of about 1 msec existed between m. levator auris and m. temporalis. The shortest latency of the EMG response in m. levator auris was 5.5 msec (110 dB SPL). A common fluctuation in response amplitude and latency was found in simultaneous recordings of muscles innervated by the facial and trigeminal nerve, respectively. This shows a common modulatory input to the startle pathway to the cranial motor nuclei. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Levator veli palatini muscle activity in relation to intraoral air pressure variation in cleft palate subjects

A comparison of the ranges of levator veli palatini EMG activity for speech versus a nonspeech task for subjects with cleft palate was the focus of this study. EMG values are also compared with subjects without cleft palate obtained in a previous study. Hooked-wire electrodes were inserted into the levator muscle of five adult subjects with cleft palate exhibiting mild hypernasality. Intraoral air pressure was measured concurrently. A blowing task was used to determine the subject's operating range for the levator muscle. Both the nonspeech and speech tasks were designed to sample the widest possible ranges of levator EMG activity. It was found that the subjects with cleft palate used a relatively high activation level for the levator muscle during speech, in relation to their total activation range, compared with the subjects without cleft palate. Implications are discussed in relation to possible anatomic and physiologic differences for cleft palate subjects compared to normal.     

The role of Müller's muscle reconsidered

It is a traditional teaching that the levator aponeurosis is the main transmitter of the levator palpebrae muscle. However, there are several points that raise doubts in this fundamental concept of the levator aponeurosis as being the primary interconnecting mechanism in upper lid elevation. Despite the structural integrity of the levator complex, drooping of the upper eyelids is seen to develop in situations such as Horner's syndrome and in times of excessive fatigue and sleepiness. Amid the controversy in the literature regarding the specific role of the levator aponeurosis in the lid-elevating mechanism, we have observed that the levator aponeurosis fails to make constant attachment to the tarsal plate. This has led us to speculate on the possible role of the posterior lamella - Müller's muscle - as the primary transmitter of the levator muscle action to the tarsal plate.     

Anatomy of radical prostatectomy as defined by magnetic resonance imaging

PURPOSE: We examined and defined anatomical structures relevant to radical prostatectomy using magnetic resonance imaging. MATERIALS AND METHODS: Before radical prostatectomy, 15 men underwent high-resolution magnetic resonance imaging studies of their pelvic floors (fast spin echo, T2 weighting of 3- to 4-mm. contiguous or overlapping slices) in axial, coronal, and sagittal planes. RESULTS: Pubovesical ligaments, rather than the commonly reported puboprostatic ligaments, were observed attaching the bladder-prostate unit to the pubis. We suggest that the part of the urethra that extends from the apex of the prostate to the bulb of the penis, which is surrounded by the striated sphincter, should be termed the sphincteric urethra rather than the membranous urethra. Further, we found no evidence that supports the traditional concept of a urogenital diaphragm. The lower part of the striated urethral sphincter was flanked on its sides by the anterior recesses of the ischioanal fossae. The portion of the levator ani, which we have termed the puboanalis sling, flanked the apex of the prostate. The most anteromedial portion of this sling inserts into the perineal body and should be termed the puboperinealis. The terminal part of the gastrointestinal tract (the part continued beyond the levator ani) should be termed the anal canal, not the rectum, as used frequently in the urologic literature. Therefore, the initial plane of dissection in radical perineal prostatectomy passes along the anterior portion of the anal canal, not the rectum. CONCLUSION: We used magnetic resonance imaging to study male pelvic floor and perineal anatomy without the artifact of dissection. This study allowed us to devise a more precise nomenclature with respect to radical prostatectomy and, in so doing, to provide a better understanding of both the retropubic and the perineal operations.     

Anatomic basis of cleft palate and velopharyngeal surgery: implications from a fresh cadaveric study

The aim of this investigation was to examine the blood supply of the normal velopharyngeal musculature and its clinical implications. Detailed dissections were performed on each side of five fresh human adult cadaveric head and neck specimens (n = 10) following carotid artery injection with liquid neoprene latex stained with green pigment. The vascular network of the soft palate was situated within its glandular layer. The velopharyngeal muscles were supplied by the following four branches of the external carotid artery: (1) ascending palatine branch of the facial artery, which supplied the palatoglossus, palatopharyngeus, musculus uvulae, and the intravelar part of the levator veli palatini; (2) ascending pharyngeal artery, which supplied the superior constrictor; (3) the previously undescribed recurrent pharyngeal artery, which supplied the extravelar part of the levator veli palatini; and (4) maxillary artery, which supplied the tensor veli palatini. All muscles except the musculus uvulae had at least a dual blood supply. Analysis of this vascular anatomy suggests that (1) the overall generous blood supply of the velum allows it to tolerate the dissection performed during intravelar veloplasty and the Furlow double opposing Z-plasty; (2) dissection around the hamulus, along the medial pterygoid plate, and in the space of Ernst should be performed carefully to avoid damage to the ascending palatine artery, ascending pharyngeal, and recurrent pharyngeal arteries; (3) vertical pharyngeal flaps are random pattern in nature; and (4) the posterior tonsilar pillar flaps of the sphincter pharyngoplasty are adequately supplied by the hamular branch of the ascending palatine artery.     

Transdermal oestrogen reduces daytime blood pressure in hypertensive women [see comment

A complex system of connective-tissue septa within the orbit has previously been described in serial histologic sections. The present study describes the anatomy of the orbital connective tissue system on high-resolution magnetic resonance (MR) images in vivo. Five volunteers aged 26 to 35 year underwent magnetic resonance imaging of the orbit on a 1 Tesla unit (Impact, Siemens, Germany). T1-weighted coronal images were obtained using a surface coil. Anatomical structures on the MR images were identified by comparison with corresponding histologic sections. On MR images of the anterior orbit, the levator aponeurosis, Lockwood ligament, transverse intermuscular ligament, common sheath, check ligaments, Tenon capsule, intermuscular septa, and palpebral ligaments can be seen. In the mid- and posterior orbit, the intermuscular orbital septa, especially the superolateral septum, the superior ophthalmic vein hammock, and septa of the radial connective tissue system are visualized. High-resolution magnetic resonance imaging is capable of delineating the major septa of the orbital connective tissue system.     

Identification of a tumor-specific methylation site in the Wilms tumor suppressor gene

The aims of this study were to determine if there were any differences in the thickness of the lip levator musculature in men and women, and whether the height of the smile line in adults was related to the thickness of the lip levator musculature. Thirty Caucasian (13 males, 17 females), and 24 Asian (11 males, 13 females) undergraduate dental students participated in this study. The subjects were placed in high, medium, and low smile-line groups, according to the height of their upper lip while smiling. The thickness of the levator labii superioris and zygomaticus major muscles was measured on ultrasound scans of the relaxed muscles. Gender, right-left side, and ethnic differences in muscle thickness were determined, and the thicknesses of the lip levator musculature in subjects in the high, medium, and low smile-line groups were compared. There were significantly more women than men with high smile-lines and the zygomaticus major muscle was significantly thicker in the women, as compared with the men. There were, however, no statistically significant differences in muscle thickness in the three smile-line groups. While it appears that women have higher smile-lines and significantly thicker zygomaticus major muscles than men, the height of the smile line is not due to the thickness of either the levator labii superioris or zygomaticus major muscles.     

Effect of posture, route of respiration, and negative pressure on palatal muscle activity in humans

Sleep apnea is worse in the supine posture and is associated with retropalatal airway narrowing or occlusion. We have, therefore, examined the effects of posture, negative pressure, and route of respiration on palatal muscle activity in 13 nonsnoring awake male subjects by using electromyography. Electromyographic activity of the levator palatini and palatoglossus was expressed as a percentage of maximum activity. Both the levator palatini (P = 0.002) and palatoglossus (P = 0.002) exhibited phasic inspiratory activity. Overall, posture did not affect the levator palatini (F = 1.58; P = 0.23) or palatoglossus (F = 0.98; P = 0.34) activity, but analysis by route of respiration showed the palatoglossus to be more active when the subjects were nose breathing supine (F = 6.64; P = 0.02). Levator palatini activity was lower when nose breathing was compared with mouth breathing in both the erect and supine postures (F = 6.67; P < 0.02). Nose breathing with the mouth held open caused an increase in palatoglossal activity (P = 0.04). Negative-pressure application (0 to -12.5 cmH2O) caused significant increases in levator palatini (P < 0.001) and palatoglossus (P < 0.001) activity, 100 ms after pressure stimulus, irrespective of route. However, the palatoglossus required significantly greater negative pressures to cause activation when applied via the nose compared with the mouth (P < 0.05). These observations indicate that the levator palatini and palatglossus have respiratory activity and are reflexly activated by negative pressure.     

The effect of catalase inhibitor 3-amino-1,2,4-triazole on coupled oxidative phosphorylation and the state of adenyl system in liver mitochondria of albino rats

Blepharoptosis is a recognized complication of cataract extraction and other ocular procedures. A 6-month waiting period is recommended before repairing postcataract ptosis because most cases resolve during this time. We report the course of a patient who developed spontaneous recovery of eyelid function 11 months after cataract surgery. She had previously undergone successful ptosis repair 8 months after cataract extraction, but developed overcorrection 3 months later as her levator function returned to normal. We recommend at least a 1-year waiting period before repair of postcataract ptosis. If corrective surgery is undertaken earlier than 1 year due to visual obstruction or for aesthetic reasons, we suggest two guidelines. The levator should be plicated rather than resected and patients should be forewarned of the possibility for a revisionary procedure if spontaneous return of levator function occurs.     

Benign ulcer in a hiatus hernia complicated with a pericardial fistula

The method of multilevel full-thickness eyelid resection combined with plication of the levator aponeurosis Müller's muscle was used to correct severe acquired ptosis. The 19 eyes of 13 patients treated with this method included neurogenic ptosis (3 eyes of 3 cases), myasthenia gravis ptosis (8 eyes of 4 cases), chronic progressive external ophthalmoplegia (4 eyes of 2 cases) and traumatic ptosis (4 eyes of 4 cases). All the patients had poor levator function. After operation their eyelids were elevated to an acceptable functional level without exposure keratopathy. The operative results were satisfactory. The operation procedure and indications were discussed.     

Helicobacter pylori in peptic ulcer disease: report of an NIH consensus conference

Preoperative electromyographic examinations of superior levator muscle were done in 36 ptotic patients using the Neurematic 2000 electromyograph. Shortening of the levator palpebrae superior was done through a combined internal and external route. In 12 patients of mild ptosis the spike voltage was all above 30 mv during contraction. When the spike voltage was above 100 mv, better operative results were obtained. In 24 patients whose ptosis was moderate or severe, the graphs of contraction generally showed simple phases with low amplitude. In 9 patients whose spike voltage was below 30 mv, their palpebral fissure did not reach the anticipated width after the operation. On the contrary, in 15 patients whose spike voltage was above 30 mv the operative results were satisfactory. It is concluded that in patients whose ptosis is moderate or severe, the operative procedure should be based on electromyographic examinations. If the spike voltage of the superior levator muscls is higher than 30 mv on contraction, simple shortening of the levator will be successful. If the spike voltage is lower than 30 mv and the graph presents simple phase or electro-tranquilization, then suspension of the frontalis muscle is preferable.     

Simplification in locating and dissecting the levator muscle of the upper eyelid in surgery for ptosis

BACKGROUND: While repairing eyelid ptosis by aponeurotic resection by anterior approach, the risk of damaging the levator complex and the conjunctiva is significant. In order to simplify the dissection between Müller's muscle and the underneath conjunctiva, we use a modification of the usual surgical technique. METHODS: Before the skin incision, the eversion of the upper eyelid allows to dissect the conjunctiva from the Müller's muscle under direct visual control, starting from the upper tarsal margin. A silicone band is then passed through the so created horizontal subconjunctival tunnel. The upper eyelid can be physiologically replaced, and the levator muscle aponeurosis exposed. The two ends of the band are then pulled on surface through two lateral incision performed close to the upper tarsal edge. Now the band plays the role of a useful landmark: every tissue above the band is levator complex; when stretched downwards, it points the upper edge of the tarsal plate. We operated by this technique 24 eyes, affected of acquired or congenital ptosis. Fourteen eyelids had already undergone ptosis surgery elsewhere. RESULTS: We achieved good-to-excellent results in all cases, without any important postoperative complications. CONCLUSIONS: The proposed manoeuvre makes easier the dissection of the inner aspect of the levator complex, because of the material control. Therefore it minimises the tissue trauma and the postoperative complications, particularly in complicated cases characterised by scarring and fibrosis.     

Central generation of grooming motor patterns and interlimb coordination in locusts

Coordinated bursts of leg motoneuron activity were evoked in locusts with deefferented legs by tactile stimulation of sites that evoke grooming behavior. This suggests that insect thoracic ganglia contain central pattern generators for directed leg movements. Motoneuron recordings were made from metathoracic and mesothoracic nerves, after eliminating all leg motor innervation, as well as all input from the brain, subesophageal ganglion, and prothoracic ganglion. Strong, brief trochanteral levator motoneuron bursts occurred, together with silence of the slow and fast trochanteral depressor motoneurons and activation of the common inhibitor motoneuron. The metathoracic slow tibial extensor motoneuron was active in a pattern distinct from its activity during walking or during rhythms evoked by the muscarinic agonist pilocarpine. Preparations in which the metathoracic ganglion was isolated from all other ganglia could still produce fictive motor patterns in response to tactile stimulation of metathoracic locations. Bursts of trochanteral levator and depressor motoneurons were clearly coordinated between the left and right metathoracic hemiganglia and also between the mesothoracic and the ipsilateral metathoracic ganglia. These data provide clear evidence for centrally generated interlimb coordination in an insect.     

Anorectal malformation: a new anatomic variant resembling an H-type fistula

A new anatomic variant of an anorectal malformation resembling an H-type fistula was observed in a newborn girl. This variant consisted of a high-grade stenosis of the anal canal below the level of the levator muscle with a blind-ending fistulous tract originating from the stenotic segment and running toward the posterior wall of the vestibulum. The embryogenesis of this malformation remains to be seen.     

Anatomy into the next millennium: quo vadis, or simply where to?

Concerns are raised regarding the status of anatomy as an academic discipline and its future. The traditional place of anatomy in the medical and other curricula is under serious threat. There is a decline in the number of clinically qualified academic staff members in anatomy departments. Options for change if anatomy is to remain among viable academic disciplines are explored.     

When hunger finds no fault with moldy corn: Food deprivation reduces food-related disgust.

The main purpose of this study was to examine if disgust toward unpalatable foods would be reduced among food-deprived subjects and if this attenuation would occur automatically even under moderate levels of food deprivation. Subjects were either satiated or food deprived for 15 hours and electromyographic activity was recorded at the levator muscle region while they were watching pictures of palatable versus unpalatable foods, and pictures of positive versus disgust-related control pictures. For control purposes, subjects' activity of the zygomaticus and corrugator muscles was also recorded. As compared with satiated subjects, food-deprived subjects exhibited stronger activity in the zygomaticus muscle region when watching pictures of palatable foods (but not when watching positive control pictures). More important, hungry subjects exhibited weaker activity in the levator muscle region when watching pictures of unpalatable foods (but not when watching disgusting control pictures). Thus, this is the first study ever to show that specific emotions (disgust) are moderated by homeostatic dysregulation automatically. Results indicate that the modulation of facial expressions might play an important role in lowering the threshold for food intake. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Pathology of the palatal aponeurosis in cleft palate

OBJECTIVE: The palatal aponeurosis is a controversial structure, both in terms of its anatomy and its function. This article points out a pathologic finding in the cleft palate condition that has not been previously described. DESIGN AND METHOD: By means of surgical dissections, this study demonstrates in detail that the palatal aponeurosis exists even in cleft palates, but it is disrupted, malpositioned, and folded in two layers. PATIENTS: This dissection method has been performed on more than 150 patients with cleft of the hard and soft palate, with or without cleft of the lip and alveolus. At the time of operation, the children were between 6 and 8 months of age. RESULTS: It is possible to dissect the two layers of the palatal aponeurosis, to unfold the aponeurosis, and to form a tough tendinous plane. CONCLUSION: For a functional physiologic reconstruction of the cleft palate, it is necessary not only to reconstruct the levator veli palatini and palatopharyngeus muscle slings, but also to approximate and suture the fibers of the palatal aponeurosis to the corresponding fibers of the opposite side after unfolding them in a medio-dorso-cranial direction. In this manner, a continuous palatal aponeurosis can be created, which subsequently can serve as a transmitter of the muscle forces.