The temporal fascia is a double lamina sandwiching a thick fat layer above the zygomatic bony arch. To characterize each lamina, their developmental processes were examined in fetuses. We observed histological sections from 22 half-heads of 10 mid-term fetuses at 14–18 weeks (crown-rump length, 95–150 mm) and 12 near-term fetuses at 26–40 weeks (crown-rump length, 215–334 mm). The superficial lamina of the temporal fascia was not evident at mid-term. Instead, a loose subcutaneous tissue was attached to the thin, deep lamina of the temporal fascia covering the temporalis muscle. At near-term, the deep lamina became thick, while the superficial lamina appeared and exhibited several variations: i) a monolayered thick membrane (5 specimens); ii) a multi-layered membranous structure (6) and; iii) a cluster of independent thick fasciae each of which were separated by fatty tissues (1). In the second and third patterns, fatty tissue between the two laminae was likely to contain longitudinal fibrous bands in parallel with the deep lamina. Varying proportions of the multi-layered superficial lamina were not attached to the zygomatic arch, but extended below the bony arch. Whether or not lobulation or septation of fatty tissues was evident was not dependent on age. The deep lamina seemed to develop from the temporalis muscle depending on the muscle contraction. In contrast, the superficial lamina developed from subcutaneous collagenous bundles continuous to the cheek. Therein, a difference in development was clearly seen between two categories of the fasciae.

Human fetal cervical vertebrae are characterized by the large zygapophysial joint (ZJ) extending posteriorly. During our recent studies on regional differences in the shape, extent, and surrounding tissue of the fetal ZJ, we incidentally found a cervical-specific structure of synovial tissues. This study aimed to provide a detailed evaluation of the synovial structure using sagittal and horizontal sections of 20 near-term fetuses. The cervical ZJ consistently had a large cavity with multiple recesses at the margins and, especially at the anterior end, the recess interdigitated with or were located close to tree-like tributaries of the veins of the external vertebral plexus. In contrast to the flat and thin synovial cell lining of the recess, the venous tributary had cuboidal endothelial cells. No or few elastic fibers were identified around the ZJ. The venous-synovial complex seems to be a transient morphology at and around birth, and it may play a role in the stabilization of the growing cervical ZJ against frequent spontaneous dislocation reported radiologically in infants. The venous-synovial complex in the cervical region should be lost and replaced by elastic fibers in childhood or adolescence. However, the delayed development of the ligament flavum is also likely to occur in the lumbar ZJ in spite of no evidence of a transient venous-synovial structure. The cuboidal venous endothelium may simply represent the high proliferation rate for the growing complex.

Human fetal cervical vertebrae are characterized by the large zygapophysial joint (ZJ) extending posteriorly. During our recent studies on regional differences in the shape, extent, and surrounding tissue of the fetal ZJ, we incidentally found a cervical-specific structure of synovial tissues. This study aimed to provide a detailed evaluation of the synovial structure using sagittal and horizontal sections of 20 near-term fetuses. The cervical ZJ consistently had a large cavity with multiple recesses at the margins and, especially at the anterior end, the recess interdigitated with or were located close to tree-like tributaries of the veins of the external vertebral plexus. In contrast to the flat and thin synovial cell lining of the recess, the venous tributary had cuboidal endothelial cells. No or few elastic fibers were identified around the ZJ. The venous-synovial complex seems to be a transient morphology at and around birth, and it may play a role in the stabilization of the growing cervical ZJ against frequent spontaneous dislocation reported radiologically in infants. The venous-synovial complex in the cervical region should be lost and replaced by elastic fibers in childhood or adolescence. However, the delayed development of the ligament flavum is also likely to occur in the lumbar ZJ in spite of no evidence of a transient venous-synovial structure. The cuboidal venous endothelium may simply represent the high proliferation rate for the growing complex.

We have previously reported that the thoracolumbar posterior nerve root shows a tortuous epidural course, based on studies of human fetuses near term. For comparison with the cervical nerve, examinations were conducted using frontal, sagittal and horizontal sections of cervical vertebrae from 22 fetuses at 30–38 weeks of gestation. The cervical nerve root showed a short, straight and lateral course near the zygapophysial joint. Multiple rather than single bundles of the cervical posterior root seemed to account for the majority of sensory nerve fibers innervating the upper extremity. Fasciculation of rootlets was evident near the thoracolumbar spinal cord, whereas it was seen in the dural pocket at the nerve exit from the dural sac although both sites were subdural. As in the thoracolumbar region, the nerve sheath was continuous with the dura mater and independently surrounded each of the anterior and posterior roots. Radicular arteries were few in the cervical region. In 2 of the 22 fetuses (31 weeks and 33 weeks), there was a segmental, unilateral abnormality of nerve rootlet fasciculation where the dorsal root ganglion was located lateral or peripheral to the intervertebral region. Long nerve roots running inferiorly are a necessary adaptation to the delayed and marked growth of the thoracolumbar vertebral column.In children, the cervical nerve roots are likely to be affected by movement or dislocation of the vertebrae. The segmental abnormality of the cervical nerve root may be linked to rare variations in the brachial plexus.

Patients on chronic hemodialysis, undergoing coronary artery bypass grafting (CABG) have high perioperative mortality and morbidity. In order to reduce the perioperative risks, we performed intraoperative hemodiafiltration (HDF) during off-pump CABG (OPCAB). A 62 year-old-man, who had been on dialysis for 2 years, was admitted with a sensation of chest compression. A coronary angiography revealed 75% stenosis with severe calcification in the left anterior descending artery and 90% stenosis in the second diagonal branch. During the operation, veno-venous HDF was started, using a double lumen catheter that was introduced into the femoral vein at the same time that a skin incision was made. During the exposure of the diagonal branch by rotating the heart, the blood flow of HDF was decreased and dehydration was halted to avoid hemodynamic deterioration. The patient was extubated 1.5h after the operation and did not require continuous hemodiafiltration (CHDF) in the intensive care unit (ICU). Routine hemodialysis was restarted on the 3rd postoperative day. The postoperative course was uneventful, and the patient was discharged to home on the 11th postoperative day. HDF during OPCAB for this chronic dialysis patient was observed to be effective and yielded an excellent postoperative recovery without CHDF in the ICU.

Integrated lecture programs for high school students involving university teaching staff have recently become popular. Here, we report on such a program involving lectures on tumor pathology attended by 110 high school students at the Yokohama City University School of Medicine. Two weeks before the lectures at our university, the students were given a 45-minute introductory lecture by a teacher at their school. The 1-day course at our university comprised an overview lecture by the author (40 minutes), light-microscopic observation of histologic specimens of normal and tumor tissues (50 minutes), and a summary with an introduction to diagnostic pathology (20 minutes). During light-microscopic observation, medical students served as teaching assistants. The high school students were given handouts of microscopic

We have used two methods for education of pathology at the Yokohama City University School of Medicine: 1) clinicopathological conferences on autopsy cases and 2) journal club using “Case Records of the Massachusetts General Hospital” published in the New England Journal of Medicine. Both methods are extremely effective for stimulating students' enthusiasm for learning, improving presentation skills, and consolidating the minds of students as future medical staff members. Furthermore, journal club enhances the affinity for reading medical English.

The elephant trunk procedure is used to close the false lumen of the distal aorta in the surgical treatment for aortic dissection. We examined the state of the false lumen thrombus and measured the diameter of the aortic dissection, using postoperative digital subtraction angiography and computed tomographic scanning. We performed the elephant trunk procedure in 24 cases in the period, between January 1995 to December 1999. Total aortic arch replacement was performed in Stanford type A dissection, and descending aorta replacement was performed in Stanford type B dissection. In all patients, thrombotic closure around the elephant trunk graft was confirmed. Thromboexclusion of the false lumen of the descending aorta was observed in 18 cases (75.0%). The secondary operation may be unnecessary, because there was a tendency towards reduction of the diameter of dissecting aorta. These data revealed that this procedure was effective. In 6 cases (25.0%), residual dissection was recognized in the thoracoabdominal aorta, but there was no case of expansion requiring further operation. Nevertheless, careful follow-up is necessary, because aneurysms could expand in the future.

Our strategy for treatment of thoracic aortic aneurysms with severely stenotic or occluded cerebral vessels is as follows. 1) The status of cerebral vessels and brain is assessed in detail by a team of neurologists and neurosurgeons, 2) cerebral surgical treatment is performed prior to aortic arch surgery, and 3) reconstruction of the total arch is performed using the arch-first technique through a median sternotomy. We successfully performed artificial graft replacement of the total aortic arch in two patients with old cerebral infarcts and severely stenotic cerebral vessels. In both cases, the operation was performed through median sternotomy under circulatory arrest by feeding the blood to the ascending aorta and draining it from the right atrium. Cerebral protection during reconstruction of the aortic arch was provided by profound hypothermia and retrograde cerebral perfusion (RCP). Prior to the incision of the aneurysm, cerebral branches were dissected to avoid escape of debris into cerebral vessels. The graft replacement was completed in 4 steps: 1) anastomosis of each of the 3 arch vessels, 2) distal anastomosis of another graft for the elephant trunk procedure, 3) anastomosis of the arch graft and the graft for the elephant trunk, and 4) proximal anastomosis. Just after cerebral branches were anastomosed to the 3 branches of the graft, the blood was supplied to the brain through the side branch of the graft instead of RCP. No signs of neurological deficit occurred postoperatively. The above protocol provided protection of high-risk patients with old cerebral infarcts from possible postoperative brain damage.

We developed a new double-lumen balloon catheter for retrograde cerebral perfusion (RCP) via jugular vein cannulation. Between November 1996 and September 2000, 34 of 73 patients treated with surgical procedures for thoracic aortic aneurysms underwent RCP using the new catheter during circulatory arrest under deep hypothermia. Nine patients underwent a median sternotomy, and 25 underwent a left thoracotomy. In all cases, the new catheter installation under fluoroscopy was easy, and it took about 15min. The mean RCP time, pressure, and flow rate were 26.8min, 20.0mmHg, and 202.6ml/min, respectively. Our procedure using the new catheter was safe and easy in RCP during circulatory arrest in aortic arch replacement regardless of surgical approaches such as a left thoracotomy or median sternotomy.