Electron microscopic studies of xeroderma pigmentosum: unusual changes in the keratinocyte

Two out of sixteen biopsies from verrucous lesions of xeroderma pigmentosum revealed unusual electronmicroscopic changes. Structures resembling anchoring fibrils and the basal lamina were noted within the grossly dilated rough endoplasmic reticulum of some basal and suprabasal keratinocytes.     

The Defibrillation Success Rate Versus Energy Relationship: Part I-Curve Fitting and the Most Efficient Defibrillation Energy

The effect of applying an energy pulse to the heart during ventricular fibrillation is described by the probability of successful defibrillation or success rate. Seven to ten (8.60 +/- 0.84: mean +/- standard deviation) defibrillation trials per energy were randomly attempted at energies which span the defibrillation success rate versus energy curve. We obtained 70.0 +/- 8.4 episodes per dog. We fit the defibrillation success rate versus energy relationship from ten dogs (20.5 +/- 1.5 kg) to four types of curves: linear, exponential, probit transformed linear, and logit transformed linear. The correlation coefficients for each fit are 0.917 +/- 0.057, 0.944 +/- 0.014, 0.926 +/- 0.51, and 0.889 +/- 0.098, respectively. We therefore conclude that the exponential curve best describes the DSRE relationship. This suggests the existence of an energy below which defibrillation does not occur. At higher energies, the exponential curve asymptotically approaches a 100% success rate, which indicates that increasing the energy produces a diminishing benefit to defibrillation success rate. The estimated energies with a 0% defibrillation success rate are surprisingly consistent among dogs, with 2.072 +/- 0.553 J. The estimated energy with an 80% defibrillation success rate is 5.217 +/- 1.091 J. The estimated defibrillation success rate corresponding to the defibrillation threshold of 3.59 +/- 1.06 J is consistent with 0.516 +/- 0.144. The estimated energies with a 0% success rate correlate well with the defibrillation thresholds with R = 0.772; P = 0.0088. Since implantable defibrillators have a limited energy supply, we determined energy efficiency by dividing defibrillation success rate by the applied energy and energy consumption by dividing the applied energy by the defibrillation success rate. The most efficient defibrillation energy occurs at the maximum energy efficiency and the minimum energy consumption. The most efficient defibrillation energy of 4.34 +/- 0.97 J determined from the exponential fit has a success rate of 0.70 +/- 0.06. The most efficient defibrillation energy can be predicted from the defibrillation threshold. Clinically, a 70% success rate may not be adequate. We, therefore, compared the energy efficiency and consumption of energies with 90% and 95% success rates to the most efficient defibrillation energy. About a 50% increase in energy from the most efficient defibrillation energy is necessary for a 90% success rate which results in about a 13% loss in energy efficiency and about a 16% increase in energy consumption. About an 84% energy increase is necessary for a 95% success rate which results in about a 24% loss in energy efficiency and about a 33% increase in energy consumption.(ABSTRACT TRUNCATED AT 400 WORDS)     

Relation of Exocrine Pancreatic Function to the Diameter of the Pancreatic and Common Bile Ducts

One hundred and thirty-nine patients were examined for possible chronic pancreatitis by means of both pancreozymin-secretin test and endoscopic pancreatography of pancreatocholangiography. Pancreatic function as assessed by the pancreozymin-secretin test was impaired in 89 (64%) of the entire group. No significant relationship was demonstrated between pancreatic secretion of fluid, bicarbonate and amylase and the diameter of main pancreatic duct in both the entire group of the subgroup of patients with pancreatic dysfunction. On pancreatogram no gross morphological abnormalities were found in a high proportion of patients whose pancreatic function was impaired in minimal to moderate degree. There was a significant linear correlation between the diameters of the main pancreatic duct and common bile duct. These data question the value of endoscopic pancreatography in the diagnosis of low to moderate grade chronic pancreatitis.     

Pancreatic Internal Fistula to the Left Pleural Cavity

A case of recurrent pancreaticopleural effusion is presented. The pleural effusion with high enzyme and protein eouteuts resulted from a pancreatic internal fistula to the left pleural cavity. A sinus tract passing throngh esophageal hiatus was demonstrated by the endoscopic retrograde pancreatography (ERP). Surgical intervention afforded complete relief of abdominal pain and elimination of the pleural effusion.     

Midline Lumbar Fusion with Cortical Bone Trajectory Screw

A novel cortical bone trajectory (CBT) screw technique provides an alternative fixation technique for lumbar spine. Trajectory of CBT screw creates a caudo-cephalad path in sagittal plane and a medio-lateral path in axial plane, and engages cortical bone in the pedicle. The theoretical advantage is that it provides enhanced screw grip and interface strength. Midline lumbar fusion (MIDLF) is composed of posterior mid-line approach, microsurgical laminectomy, and CBT screw fixation. We adopted the MIDLF technique for lumbar spondylolisthesis. Advantages of this technique include that decompression and fusion are available in the same field, and it minimizes approach-related damages. To determine whether MIDLF with CBT screw is as effective as traditional approach and it is minimum invasive technique, we studied the clinical and radiological outcomes of MIDLF. Our results indicate that MIDLF is effective and minimum invasive technique. Evidence of effectiveness of MIDLF is that patients had good recovery score, and that CBT screw technique was safety in clinical and stable in radiological. MIDLF with CBT screw provides the surgeon with additional options for fixation. This technique is most likely to be useful for treating lumbar spondylolisthesis in combination with midline decompression and insertion of an interbody graft, such as the transforaminal lumbar interbody fusion or posterior lumbar interbody fusion techniques.     

Frameless Stereotactic Biopsy with Intraoperative Computed Tomography “Assessment of Efficacy and Real Target Registration Error”

Frameless stereotactic brain biopsy (FSB) with navigation system has been widely used. We reported preliminary experience of FSB with intraoperative computed tomography (iCT) and examined the usefulness of this novel adjuvant technique and real target registration error (rTRE) of FSB. The FSB with 5-aminolevulinic acid (5-ALA) and iCT was performed on 10 patients. The gadolinium-enhanced lesions on magnetic resonance image were defined as the biopsy target. In the procedure, iCTs were scanned twice, for autoregistration of the navigation system and for confirmation of the position of the actual inserted biopsy needle. The red fluorescence of the samples was observed under excitation with violet-blue light through a low-cut filter of neurosurgical microscope. The distance between the planned target and the tip of the biopsy needle in the image of iCT was calculated in a workstation for the assessment of rTRE. The median volume of the target was 12.13 mL (0.06-39.15 mL). We performed the surgical procedure in a prone position in four patients. None to faint 5-ALA-induced fluorescence was observed in six samples. There existed no sampling errors. The mean target distance between the planned and real targets of the mean rTRE of FSB was 2.7 ± 0.56 mm. The real TRE of FSB was first reported and was larger than the reported rTRE exactly calculated from the fiducial registration error. iCT guarantees accurate tumor sampling with autoregistration regardless of the surgical position and prevents inaccurate biopsy to occur even with ALA fluorescence assistance.     

Anatomical Limitation of Posterior Spinal Myelotomy for Intramedullary Hemorrhage Associated with Ependymoma or Cavernous Malformation of the High Cervical Spine

Spinal intramedullary tumors such as ependymoma or vascular lesions such as cavernous malformation are often at risk of intramedullary hemorrhage. Surgical procedures involving the high cervical spinal cord are often challenging. This technical note included four patients who presented with acute, subacute, or gradual onset of spinal cord dysfunction associated with intramedullary hemorrhage at the C1 or C1/2 level of the high cervical spine. The mean age was 46.3 years (16-74 years). All patients underwent posterior spinal cord myelotomy of the posterior median sulcus or posterolateral sulcus. It was not to exceed the caudal opening of the fourth ventricle (foramen of Magendie) and was assumed to be as high as the caudal medulla oblongata. Total removal of the intramedullary ependymoma or cavernous malformation occurred in three of four cases, and the remaining case had subtotal removal of the ependymoma. None of the patients showed postoperative deterioration of the neurological condition. Pathological examination of all cases revealed intramedullary hemorrhage was associated with ependymoma or cavernous malformation. Posterior spinal myelotomy should be limited to the caudal opening of the fourth ventricle (foramen of Magendie), that is the caudal medulla oblongata, to avoid the significant deterioration after surgery.