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Successful heterotopic heart transplantation in rat.

Heterotopic heart transplantation in rats has become a substantial tool for numerous investigations. This report describes a surgical technique of infrarenal heterotopic heart transplantation with a prodigious surgical success rate which was developed over many years of practice. Difficulties arising from anatomic variations are depicted and alternative approaches are discussed.

Abdomen↗

Reconstruction of the hand and upper limb with free flaps based on musculocutaneous perforators.

Since the advent of perforator flaps, a wide variety of applications have been documented. This study focuses on free flaps based on musculocutaneous perforators, because they have not been well-described in the literature of upper-limb reconstruction. They can be trimmed to be thin and pliable, and may provide large flaps with multiple components on the same pedicle to facilitate three-dimensional inset of flaps. Microvascular free flaps based on musculocutaneous perforators were performed in 36 cases for reconstruction of the thumb and thenar web, palm, dorsum of the hand, wrist, and forearm. They included the anterolateral thigh perforator flap (27 cases), thoracodorsal perforator flap (5 cases), and deep inferior epigastric perforator flap (4 cases). In 2 other cases not included in this series, the thoracodorsal perforator flap could not be elevated due to anatomical variations. There was no failure in this series, but complications included: 1) hematoma in 2 cases, and 2) infection in 2 cases with flap rim necrosis which was treated by a local rotation flap and skin graft. The thin flaps facilitated secondary reconstructive procedures, and only minor effort was required for the debulking procedure of the flaps. On average, these patients required 2.3 occasions of secondary procedures for further reconstruction following coverage with a perforator flap. The perforator flaps provide medium-thickness flaps for coverage of large defects in the upper limb with improved aesthetics and function. With careful dissection of the musculocutaneous perforators and primary thinning of the flaps, the use of a perforator flap is quite safe. Preservation of the muscles leads to better preservation of donor-site functions. Less requirement of secondary debulking procedures is a great advantage. However, caution should be taken in the presence of wound infection.

Adolescent↗

Peroneal nerve lesion after sural nerve graft harvest: an unusual complication--case report.

After harvesting of the sural nerve, the patient developed a partial palsy of the common peroneal nerve due to a lesion of the peroneal nerve and a neuroma of the sural nerve stump. Motor function recovered after performing neurolysis of the common peroneal nerve and mobilization of the neuroma. The sural nerve, in this case originating from the common peroneal nerve, was harvested using a nerve stripper and four small skin incisions. Direct lesion by the forced use of the nerve-stripping instrument followed by the formation of a neuroma close to the peroneal nerve are the suspected reasons for motor dysfunction. Although many authors report using a nerve stripper as a safe, less invasive method to gain nerve material for transplantation, we recommend lengthening the skin incision so as to be aware of anatomical variations and to refrain from pulling the nerve distally to avoid the described complications.

Adult↗

Cerebral white matter in the centrum semiovale exhibits a larger N-acetyl signal than does gray matter in long echo time 1H-magnetic resonance spectroscopic imaging.

Long echo time (272 ms) 1H magnetic resonance spectroscopic imaging was used to measure the relative magnitudes of the N-acetylaspartate (NAA) signal in a variety of anatomically defined brain structures (centrum semiovale, thalamus, medial frontal cortex, and genu of the corpus callosum) composed primarily of gray matter or white matter. Six normal young adult humans aged 30-40 were studied. With a 95% level of statistical confidence, the white matter in the centrum semiovale (CSO) produced a more intense NAA signal than did the gray matter in the thalamus and the frontal cortex. Differences between the white matter regions were also noted. The CSO white matter's NAA signal yielded a larger NAA signal than did the white matter of the genu of the corpus callosum. Possible reasons for the anatomical variation in the cerebral NAA signal intensity are discussed.

Adult↗

Transabdominal ultrasound measurement of pelvic floor muscle activity when activated directly or via a transversus abdominis muscle contraction.

AIMS: The purpose of the present study was to compare the effectiveness of instruction to contract the pelvic floor muscles (PFM), the transversus abdominis (TrA), and the TrA + PFM visualized as displacement of the pelvic floor by ultrasound. MATERIALS AND METHODS: Twenty female physical therapists, mean age 41.1 years (range 26-56) participated in the study. A 3.5 MHz 35 mm curved linear array ultrasound transducer (Dornier Medtech) was placed in the mid-sagittal plane immediately suprapubically, angled at 15-30 degrees from the vertical depending on subcutaneous fat and anatomical variations, to image the pelvic floor. Six trials of three maneuvers in random order were performed: contraction of PFM, TrA, and TrA + PFM. RESULTS: In spite of correct contractions assessed by palpation and clinical observation, one subject demonstrated a downward movement of the pelvic floor during PFM contraction on ultrasound. Six subjects (30%) showed a downward movement during a TrA- contraction, and two during the combined TrA + PFM contraction. Instruction to contract PFM produced significantly greater mean displacement: 11.2 mm (95% CI 7.2-15.3) than TrA 4.3 mm (95% CI -0.2-8.8), P < 0.01, and combination: 8.5 mm (95% CI 5.2-12), P = 0.04. Hence, instruction of PFM contraction produced a 61.6% greater displacement of the pelvic floor in the correct direction than a TrA contraction. CONCLUSIONS: It is concluded that ultrasound is a more valid method than palpation and clinical observation to assess PFM function, and that instruction to contract the PFM produces a significantly more effective pelvic floor muscle contraction than instruction to perform a TrA contraction.

Abdomen↗

Transvaginal chorionic villus sampling.

Chorionic villus sampling (CVS) with either transcervical catheters or transabdominal needles is a widely-accepted method for prenatal diagnosis. However, there exists a small subset of patients in whom sampling is difficult or impossible with either route because of individual anatomic variations. A new method of chorionic villus biopsy has been developed to circumvent these problems, utilizing transvaginal chorionic needle aspiration guided by an intravaginal ultrasound probe. This technique was performed successfully in 15 patients in whom villi could not be obtained by either of the conventional methods. This method now makes CVS possible in essentially all women regardless of their uterine anatomy or placental placement; it may also prove useful for very early chorionic sampling.

Adult↗

Thoracic wall lesions in children.

Our objective was to review the clinical features and radiographic manifestations of chest wall lesions in a pediatric chest unit. Twenty-five patients (11 males and 14 females, aged 14 months to 15 years) were suspected of having a chest wall lesion on the basis of clinical examination and chest radiograph. A retrospective review of clinical characteristics and radiographic findings was performed in order to define the pathology and extent of lesions and outcomes of chest wall diseases in children. Thirty-six percent of pediatric patients studied for thoracic abnormalities had anatomical variations of the thoracic cage such as sternal titling, bifid ribs, and costal cartilage convexities. Tuberculous infections of the sternum and ribs were seen in 4 cases. Osteochondromas were seen in 4 patients, and were especially noted in patients with a history of familial exostosis. Other malignant thoracic wall tumors included in this study included chondrosarcoma (n=1), Ewing's sarcoma (n=1), and primitive neuroectodermal tumor (n=2). In conclusion, the protruding lesions arising from the chest wall demonstrate a wide range of normal, congenital variant, and pathologic lesions arising from the soft tissues and bony components. Those with life-threatening lesions (less likely located in the parasternal region) are more prone to have chest pains and dyspneic respirations; in most cases, plain chest radiographs tend to have a high rate of bony or pleural involvement as well as thoracic deformities. In an endemic area of tuberculosis, costal tuberculosis should be considered in undiagnosed bony lesions; a chest CT scan could be diagnostically useful.

Adolescent↗

Muscular and other abnormalities in a case of Edwards' syndrome (18-trisomy).

This paper describes the anatomical variations observed in a specimen exhibiting Edwards' Syndrome (18-trisomy). The clinical and autopsy data are compared with those reported in earlier literature. Aside from having a tracheoesophageal fistula, the viscera were characterized by abnormalities of the heart, lungs, liver and kidneys. The facial musculature was relatively undifferentiated. Only a few abnormalities were recorded in the otomandibular and suprahyoid structures. The infrahyoid region had three pairs of supernumerary muscles, including the "sternohyoideus azygos." The bluk of abnormalities were found in the muscles and nerves of the upper limb. These included the absence of the palmaris longus and brevis, the subclavius and the extensor digiti quinti proprius; the presence of supernumerary muscles, e.g., the "rhomboideus occipitalis," the "latissimocondyloideus," and the "subclavius posticus." The deltoid and the pectoralis major were fused to form the "deltopectoral" complex. A definitive musculocutaneous nerve was found in the right arm only. In the lower extremity supernumerary muscles included the "tenuissimus," "peroneus quinti digiti," and the "extensor primi internodii hallucis."

Chromosomes, Human, 16-18↗

Lack of teratogenic effects of air at high ambient pressure in rats.

The purpose of the research was to determine if pregnant rats subjected to a maximum tolerated duration of exposure to air at 6 atmospheres absolute pressure (ATA) (50.3 meters seawater) would have an increased frequency fetal death, resorption, low birth-weight, or malformations. Ninety pregnant rats were assigned to one of three exposure schedules during organogenesis: days 9-11, 12-14, or 15-17, and were randomized between one treatment and two control groups. The treatment group was subjected to 6 ATA for 70 minutes with compression and decompression at 1.8 ATA (18.3 meters seawater)/minute. Control groups were exposed to either 1 ATA of air (surface) within the hyperbaric chamber, or 1 ATA of air outside the chamber. For 30 minutes following decompression, chamber-treated animals were placed in a slow, motor-driven rotating cage, and assessed for gait disturbances from decompression sickness. On Day 20 of gestation, laparotomy was performed, and corpora lutea, implantations, and resorptions were counted. Fetuses were weighed, sexed, and examined for gross malformations. Subsequently, they were fixed, sectioned, and examined for visceral anomalies. Minor visceral anomalies and anatomical variations were present in 16.3% of all fetuses; however, no significant differences existed between groups. Similarly there were no significant differences when number of resorptions, number of dead fetuses, mean fetal weights, and malformations were compared by analysis of variance. Finally, there was no relation between symptoms of decompression sickness and any of the above measures. These results indicate that exposing rats to air at increased atmospheric pressure does not affect fetal health or survival.

Air Pressure↗

An anatomical study of human otocephaly.

This study describes the gross anatomic variations observed in a 32-week male fetus diagnosed as having otocephaly. Special attention was given to the muscular, peripheral nervous, and vascular systems of the entire body. External features included approximation of the ears on the front of the neck, underdevelopment of the lower jaw, and a small oral cavity. The mandible, maxillae, and zygomatic bones were smaller than normal and appeared shifted in a ventrocaudal direction. The middle ear ossicles were fused and abnormally positioned. The tongue was positioned abnormally and malformed. The muscles of mastication were fused in the midline and formed the floor of the oral cavity. The variations were similar to the spectrum of abnormalities reported in two cases in the literature. Because of this finding, it is possible that the causative events leading to these deviations were similar in the three cases. Possible mechanisms are considered which could lead to the observed malformations seen in these cases. There were also several muscle and nerve anomalies outside of the head region.

Abnormalities, Multiple↗

Potential applications of intraoperative lymphatic mapping in vulvar cancer.

OBJECTIVE: We describe early results of and potentially important anatomic findings with intraoperative lymphatic mapping in patients with vulvar cancer. METHODS: Isosulfan blue was injected into the dermis at the leading edge of the vulvar lesion in 21 patients. One to five minutes later a standard groin incision was made and carried to the superficial fascia. After gentle dissection, the afferent lymphatic channel and/or sentinel lymph node was identified by its bright blue color. The sentinel node was removed and then the superficial inguinal lymphadenectomy was completed. RESULTS: The 21 patients, ranging in age from 23 to 85 years (median, 52 years), underwent intraoperative lymphatic mapping. The clinical stages were as follows: T1 in 9, T2 in 10, T3 in 1, and unknown in 1 patient with a prior wide local excision. Two patients had palpably suspicious nodes. Ten patients had lateral lesions, and 11 had midline tumors. Eight of the 11 patients had bilateral groin dissections, making a total of 29 groins dissected. The sentinel node was identified in 18 patients (86%) and in 19 groins (66%). Five patients had unilateral node metastases, and one patient had bilateral node metastases. A sentinel node was found in five of these seven groins. A total of 238 nodes were removed (median, 8.2 nodes per groin). In no case was a nonsentinel node positive if the sentinel node was negative. In one patient the only metastasis was microscopic tumor in the sentinel lymph node. In one case, the sentinel node was found below the cribriform fascia. The sentinel node could not be identified in either groin in one patient with a clitoral primary; however, dye was seen in lymphatic channels passing under the symphysis pubis. The sentinel node was identified in various sites within the superficial compartment including lateral to the femoral artery and at the extreme medial border of the dissection. No complication related to the injection of isosulfan blue was seen. CONCLUSION: Intraoperative lymphatic mapping is safe and simple to perform and may help identify the sentinel node, define the extent of superficial inguinal lymphadenectomy, and identify uncommon anatomic variations.

Adult↗

Endoscopic third ventriculostomy in the treatment of hydrocephalus in pediatric patients.

Advances in surgical instrumentation and technique have lead to an extensive use of endoscopic third ventriculostomy in the management of pediatric hydrocephalus. The aim of this work was to point out the leading aspects related to this technique. After a review of the history, which is now almost one century last, the analysis of the endoscopic ventricular anatomy is aimed to detail normal findings and possible anatomic variations which might influence the correct conclusion of the procedure. The overview of modern endoscopic instrumentation helps to understand the technical improvements that have contributed to significantly reduce the operative invasiveness. Indications are analysed from a pathogenetic standpoint with the intent to better understand the results reported in the literature. A further part of the paper is dedicated to the neuroradiological and clinical means of outcome evaluation, which are still a matter of debate. Finally a review of transient and permanent surgical complications is performed looking at their occurrence in different hydrocephalus etiologies.

Child↗

A preliminary report of the HTK randomized multicenter study comparing kidney graft preservation with HTK and EuroCollins solutions. HTK Study Group.

The main goal of transplantation is to restore good renal function and to improve the quality of life of thousands of dialysis patients, something which can only be achieved by providing them with well functioning grafts. Delayed renal allograft function is a serious problem. It is important to prevent this complication because it makes the diagnosis of acute rejection in the early postoperative period difficult, increases the necessity for diagnostic procedures, introduces dialysis treatments and prolongs hospital stay. The aetiology of delayed graft function (DGF) is multifactorial, and factors including donor management, technique used for organ procurement and preservation, age, anatomical variations in the graft, ischemia periods, use of cyclosporine A (CyA) or recipient immunological reactions have been implicated. Using different preservation solutions DGF rates vary from 30% to 60%. Recent clinical data have demonstrated better preservation and improved renal function posttransplant with HTK and University of Wisconsin (UW) solutions compared to EuroCollins solution. In a randomized multicenter study in collaboration with the Eurotransplant organ exchange organization, the efficacy of the HTK solution in renal transplantation was compared to EuroCollins and UW solutions in two parallel prospective randomized trials. The first preliminary results comparing HTK and EuroCollins solutions are reported here.

Creatinine↗

Stereotactic localization using fast spin-echo imaging in functional disorders.

Fast Spin-Echo Magnetic Resonance Imaging facilitates multiplanar target and trajectory selection in functional disorders by rapidly delineating gray matter, white matter, vascular, and ventricular structures. Errors due to anatomic variation or co-existing lesions can be avoided as are movement artifacts. Although not a substitute for physiologic target corroboration, the method facilitates safety and efficacy of "functional" stereotactic procedures.

Brain↗

Bilateral synovial coracoclavicular joints: MRI demonstration.

Bilateral coracoclavicular joints, an anatomical variation, are described by radiography and MRI. MRI enabled precise identification of the nature of these joints. They were true synovial joints with cartilage and synovial fluid. To the best of the authors' knowledge, this is the first demonstration of such joints by MRI.

Aged↗

One hundred consecutive laparoscopic cholangiograms. Results and conclusions.

BACKGROUND: In 100 consecutive patients who underwent laparoscopic cholecystectomy, the feasibility, reliability, and cost of routine laparoscopic cholangiography were prospectively studied. METHODS: Fluoroscopic cholangiograms with multiple exposures were successfully completed in all patients in an average time of 6.9 min. RESULTS: Twenty-one percent were abnormal, and 15 common duct stones and 6 significant anatomic anomalies detected. Thirteen out of 15 patients with common duct stones had preoperative suspicion of common duct stones. Two out of 15 were completely unsuspected. The average cost of cholangiography was $768, and there were no complications related to the procedure. There were no false interpretations. CONCLUSIONS: When compared with selective preoperative endoscopic retrograde cholangiopancreatography (ERCP), routine laparoscopic cholangiography is safer, more accurate, and less costly, and may have the added benefit of potentially reducing iatrogenic injuries in patients with anatomic variations. Routine laparoscopic cholangiography should be considered by all surgeons.

Adult↗

Meniscal ossification. I. Human.

Ossicles appearing in the medial menisci of three patients appeared to be post-traumatic in two and developmental in one. The histologic analysis in the two post-traumatic patients showed relatively normal bone and cartilage, but without the specific structural cartilaginous adaptations found in a naturally occurring large animal model. The third patient, with tibia vara and TAR (thrombocytopenia--absent radius) syndrome, developed the ossicle spontaneously. He is the youngest reported patient, to date, to develop this anatomic variation.

Adolescent↗

Meniscal ossification. II. The normal pattern in the tiger knee.

Examination of knee menisci of Bengal tigers revealed ossicles within the cartilaginous anterior horn of each medial meniscus. This ossification was not evident in the neonatal animal, but was present in animals aged 20 months or older. The ossicle appeared prior to the completion of skeletal maturation at the knee, and was composed of normal remodeling trabecular bone. While most animals had a single, variably sized ossicle, multiple ossicles also occurred. The meniscal cartilage apposed to the femoral articulation exhibited a distinct columnar pattern in the region of the ossicle, in contrast to the non-columnar pattern throughout the bulk of the meniscus, including the ossicle side apposed to the tibial plateau. In this particular large mammalian species medial meniscal ossification appears to be a normal anatomical variation that progressively develops following birth, and may serve as a model for the phylogenetic (developmental) theory of etiology.

Aging↗