Overall activity of all masticatory muscles during lateral excursion.

Quantification of the overall activity of every masticatory muscle is requisite for the analysis of stomatognathic function, which has not been accomplished by conventional electromyography. We used positron emission tomography and 18F-fluoro-deoxy-glucose to quantify the overall activity of every masticatory muscle during lateral excursion, and to evaluate the relative contribution of each masticatory muscle to lateral excursion. The present study suggested that lateral and medial pterygoid muscles are more responsible for lateral excursion than are masseter and temporal muscles. In particular, the contralateral lateral pterygoid muscle plays a major role, followed by the contralateral medial pterygoid muscle.

Brain activity during distention of the descending colon in humans.

Brain-gut interaction is considered to be a major factor in the pathophysiology of irritable bowel syndrome. However, only limited information has been provided on the influence of gastrointestinal tract stimulation on the brain. Our aim in this study was to determine the specific regions of the brain that are responsible for visceral perception and emotion provoked by distention of the descending colon in humans. Fifteen healthy males aged 22 +/- 1 participated in this study. Using a colonoscope, a balloon was inserted into the descending colon of each subject. After sham stimulation, the colon was randomly stimulated with bag pressures of 20 and 40 mmHg, and regional cerebral blood flow was measured by [(15)O] positron emission tomography. The subjects were asked to report visceral perception and emotion using an ordinate scale of 0-10. Colonic distention pressure dependently induced visceral perception and emotion, which significantly correlated with activation of specific regions of the brain including the prefrontal, anterior cingulate, parietal cortices, insula, pons, and the cerebellum. In conclusion, distention of the descending colon induces visceral perception and emotion. These changes significantly correlate with activation of specific regions in the brain including the limbic system and the association cortex, especially the prefrontal cortex.

Reliable, minimally invasive oromandibular reconstruction using metal plate rolled with pectoralis major myocutaneous flap.

The purpose of this study was to minimize the surgical invasiveness to the donor site and the amount of the primary reconstruction time after oromandibular tumor resection. Oromandibular reconstruction was performed only using a pectoralis major myocutaneous flap and a metal plate. The pectoralis major myocutaneous flap was grafted to the oral cavity defect by rolling and wrapping around the metal plate with the muscle of the flap. No early postoperative complications have been noted in all seven patients. An average of 2 years and 1 month has past since surgery, and to date no infections, plate exposure, or plate breakage have been observed in any of the patients. The safety of the oromandibular reconstruction using a metal plate was improved by rolling the muscle of the pectoralis major myocutaneous flap around the metal plate. The present method was shown to be a rational technique that allowed primary reconstruction of the oral cavity and mandible in a minimally invasive manner in a short time.

Saccular renal artery aneurysm treated with an autologous vein-covered stent.

A 32-year-old woman underwent an autologous saphenous vein-covered stent deployment for the treatment of a saccular aneurysm on the distal renal artery. Complete exclusion of the aneurysm was immediately obtained. One year after the treatment, remarkable shrinkage of the aneurysm was demonstrated by means of computed tomography, and wide patency of the renal artery and the stent was shown by means of angiography.

Evaluation of resting brain conditions measured by two different methods (i.v. and oral administration) with 18F-FDG-PET.

Our aim was to evaluate regional differences between brain activity in two resting control conditions measured by 3D PET after administration of FDG through either the intravenous (i.v.) or the oral route. Ten healthy male volunteers engaged in the study as the i.v. group (mean age, 26 +/- 9.3 years, +/- S.D.) who received FDG intravenously and another 10 volunteers as the oral group (mean age, 27.9 +/- 11.3 years, +/- S.D.) who received FDG per os. A set of 3D-PET scans (emission and transmission scans) were performed in both groups. To explore possible functional differences between the brains of the two groups, the SPM-96 software was used for statistical analysis. The results revealed that glucose metabolism was significantly higher in the superior frontal gyrus, superior parietal lobule, lingual gyrus and left cerebellar hemisphere in the i.v. group than in the oral group. Metabolically active areas were found in the superior, middle and inferior temporal gyrus, parahippocampal gyrus, amygdaloid nucleus, pons and cerebellum in the oral group when compared with the i.v. group. These differences were presumably induced by differences between FDG kinetics and/or time-weighted behavioral effects in the two studies. This study suggests the need for extreme caution when selecting a pooled control population for designated activation studies.

Mapping energy metabolism in jaw and tongue muscles during chewing.

Investigators have used positron emission tomography with 18F-fluoro-D-deoxyglucose to obtain information not only for the diagnosis of cancers, but also for researching physiology in skeletal muscles. The aim of this study was to evaluate the activities of the jaw and tongue muscles during gum-chewing. Five volunteers aged 32-61 years were studied by positron emission tomography. They were requested to chew two pieces of chewing gum for 30 min after intravenous injection of 18F-fluoro-D-deoxyglucose. 18F-fluoro-D-deoxyglucose uptake in the intrinsic tongue muscle was significantly (p < 0.05) higher than that in the masseter, temporal, and medial pterygoid muscles. Heterogeneous uptake of 18F-fluoro-D-deoxyglucose was observed in the masticatory muscles. In addition, the tongue exhibited higher activity than the masticatory muscles. In conclusion, positron emission tomography with 18F-fluoro-D-deoxyglucose appeared to be a useful technique for investigating the physiologic activities of the skeletal muscles, which have been difficult to examine by conventional methods.

Surgical treatment for epidural abscess in the posterior cranial fossa using trapezius muscle or musculocutaneous flap.

Two patients developed an epidural abscess in the posterior cranial fossa following tumor dissection from the occipital region of the head and underwent surgical treatment. After debridement of necrotic and infectious tissues inside the abscess was performed, the empty cavity was filled and the tissue defect was reconstructed by using a trapezius muscle flap or a trapezius musculocutaneous flap. Both patients had good clinical results, and their abscesses were healed. The trapezius muscle flap and trapezius musculocutaneous flap were quite useful in the treatment for epidural abscess in the posterior cranial fossa.

An ipsilateral superdrainaged transverse rectus abdominis myocutaneous flap for breast reconstruction.

A conventional single pedicled TRAM (transverse rectus abdominis myocutaneous) flap is a musculocutaneous flap widely used for breast reconstruction. However, complications such as partial flap necrosis, fat necrosis, and fatty induration may occur as a result of unstable blood flow circulation to the flap. One major factor is venous congestion in the flap. In an effort to obtain more stable TRAM flap blood circulation, we anastomosed the ipsilateral deep inferior epigastric vein of a pedicled TRAM flap to the thoracodorsal vein. This procedure provides superdrainage by means of enhanced venous perfusion. This flap with superdrainage augmentation is referred to as a superdrainaged TRAM flap (12 patients). Changes in cutaneous blood flow were also assessed by measurement of cutaneous blood flow in zone IV using a laser blood flow meter (8 patients). The patients who underwent breast reconstructive surgery using this technique showed no evidence of postoperative complications such as flap necrosis, fat necrosis, or fatty induration. Satisfactory results were obtained during breast reconstruction in patients who had previously undergone a radical mastectomy with resultant large areas of tissue defects. In addition, the two patient groups, 12 patients with superdrainaged TRAM flap and 20 patients with single pedicled TRAM flap, were compared to assess differences in complications. The incidence of partial flap necrosis, fat necrosis, and fatty induration was lower among patients with superdrainaged flap than those with single pedicled flap.

A method that preserves circulation during preparation of the pectoralis major myocutaneous flap in head and neck reconstruction.

The present article describes a method that preserves circulation during the preparation of the pectoralis major myocutaneous flap used in head and neck reconstruction. The major disadvantage of this flap is its poor circulation and consequent partial necrosis. To solve this problem, we analyzed the circulation and hemodynamics of the pectoralis major myocutaneous flap (the perforator of the anterior intercostal branch located about 1 to 2 cm medial to the areola in the fourth intercostal space is important), evaluated the safe donor sites in the chest wall for a skin island (the perforator is included on the skin island's central axis), improved the surgical procedure for elevating flaps (for preventing perforator injuries), and devised a means to transfer flaps, thereby increasing the range of the flaps (the transfer route is under the clavicle). Using this technique, head and neck reconstruction was performed on 62 patients. The diagnosis included oral cancer (21), oropharyngeal carcinoma (10), parotid carcinoma (10), hypopharyngeal carcinoma (9), and other head and neck malignant tumors (12). Of these, partial or marginal necrosis of the flap caused by circulatory problems was detected in three patients (5 percent). Using our method, the problems associated with inadequate circulation in the pectoralis major myocutaneous flap were greatly alleviated, thus reconfirming the usefulness of this flap in head and neck reconstruction.