The splenium of the corpus callosum: embryology, anatomy, function and imaging with pathophysiological hypothesis.

BACKGROUND AND PURPOSE: The splenium of the corpus callosum is the most posterior part of the corpus callosum. Its embryological development, anatomy, vascularization, function, imaging of pathology, possible pathophysiological mechanisms by which pathology may develop and the clinical consequences are discussed. METHODS: A literature-based description is provided on development, anatomy and function. MR and CT images are used to demonstrate pathology. The majority of pathology, known to affect the splenium, and the clinical effects are described in three subsections: (A) limited to the splenium, with elaboration on pathophysiology of reversible splenial lesions, (B) pathology in the cerebral white matter extending into or deriving from the splenium, with special emphasis on tumors, and (C) splenial involvement in generalized conditions affecting the entire brain, with a hypothesis for pathophysiological mechanisms for the different diseases. RESULTS: The development of the splenium is preceded by the formation of the hippocampal commissure. It is bordered by the falx and the tentorium and is perfused by the anterior and posterior circulation. It contains different caliber axonal fibers and the most compact area of callosal glial cells. These findings may explain the affinity of specific forms of pathology for this region. The fibers interconnect the temporal and occipital regions of both hemispheres reciprocally and are important in language, visuospatial information transfer and behavior. Acquired pathology may lead to changes in consciousness. CONCLUSION: The development, location, fiber composition and vascularization of the splenium make it vulnerable to specific pathological processes. It appears to play an important role in consciousness.

Ehlers-Danlos arthrochalasia type (VIIA-B)--expanding the phenotype: from prenatal life through adulthood.

The Ehlers-Danlos syndromes (EDS) form a clinically and genetically heterogeneous group of inherited connective-tissue disorders characterized by joint hypermobility, tissue fragility and skin abnormalities. Six subtypes have been well characterized based on clinical features and molecular genetic abnormalities. The arthrochalasia type EDS (formerly types VIIA and B) is characterized by severe generalized joint hypermobility with multiple dislocations including congenital bilateral dislocation of the hips, muscular hypotonia and distinct dysmorphic features. The diagnosis of the arthrochalasia type EDS is of importance in the neonatal period because of consequences of physical disability in later life. However, the differential diagnosis may be difficult because of overlap with other hypermobility syndromes. In addition, the significant hypotonia may direct the physician toward various neuromuscular diagnoses. As patients become older, the hypotonia decreases and facial features become less distinct. In this report, we describe seven patients at different ages. Timing of diagnosis varied from prenatal life to adult age. The diagnosis of EDS type VII was confirmed by biochemical studies or mutation analysis showing characteristic mutations in COL1A1 and COL1A2. These mutations result in skipping of exon 6, which leads to defective collagen synthesis. For physicians treating patients with EDS type VII, achieving mobility for the patient is the greatest challenge and it may be impossible because of recurrent dislocations of nearly all joints in severe cases.

Vascular responsiveness in the microcirculation of patients with systemic lupus erythematosus is not impaired.

As endothelial dysfunction is one of the earliest signs of atherosclerosis, which is accelerated in systemic lupus erythematosus (SLE), we assessed whether vascular responses of the cutaneous microcirculation are disturbed in SLE patients and influenced by Raynaud's phenomenon (RP). Laser Doppler fluxmetry (LDF) was used in combination with iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP), an endothelium-dependent and endothelium-independent vasodilator respectively. 42 SLE patients with inactive disease, 12 of whom had RP and 19 age- and sex-matched controls were included. Furthermore, traditional and non-traditional risk factors for cardiovascular disease (CVD) were assessed, and markers of inflammation and endothelial activation were measured. Vascular responses of SLE patients without RP did not differ from controls. However, SLE patients with RP exhibited decreased vasodilatation compared with controls. SLE patients with RP also had longer arrival times of ACh and SNP than controls. Markers of inflammation and von Willebrand factor were increased in SLE patients. Smoking, the presence of SLE and RP were negatively associated with vascular responses in univariate analysis. In multivariate analyses, the only independent variable of vascular responses to ACh and SNP was the presence of RP. Despite signs of endothelial activation, SLE patients with inactive disease do not have altered vascular responses in the microcirculation compared with controls. In SLE patients with RP, cutaneous vascular responses to both ACh and SNP are impaired. Therefore, LDF of the microcirculation seems not to be the appropriate method to distinguish those SLE patients with an increased risk to develop CVD.

Field study of the prevalence of lameness in horses with back problems.

A population of 805 horses (70 per cent dressage, 20 per cent show jumpers and 10 per cent trotters) with orthopaedic problems was examined for signs of lameness and back problems, irrespective of their original complaints. In the horses with a back problem the prevalence of lameness was 74 per cent, and back problems were diagnosed in 32 per cent of the lame horses. These percentages were significantly higher than those recorded in a control population of 399 horses, of which 20 per cent were lame and 12 per cent had back problems. In the group of horses with orthopaedic problems there was a strong association between lameness and back problems and, in particular, there was a high prevalence of lameness among the horses with back problems.

[Malignant melanoma of the pelvis as a possible cause of pelvic limb lameness in two gray mares]. / Maligne melanoom in het bekken als mogelijke oorzaak van een bewegingskreupelheid in het achterbeen bij twee schimmelkleurige paarden.

Two grey mares, a 12-year-old Arabian and a 13-year-old Lippizaner cross, were referred for chronic pelvic limb lameness and abduction of the limb during the non supporting phase of the stride. The clinical examination revealed melanomas under the tail and on the perineum, and oedema of the proximal lame limb. A mass in the pelvic area was detected on rectal palpation. Laparoscopy was performed and the provisional diagnosis of malignant melanoma was made. Histological examination of the biopsy taken under laparoscopic control from the mass in the pelvis confirmed the diagnosis of malignant melanoma. In the postmortem examination a large black mass in the pelvis and metastases in several organs were diagnosed. The process under the tail showed microscopically the characteristics of dermal melanomatosis. The metastases showed the appearance of a malignant melanoma. The lameness and abduction during the non supporting phase of the stride were possibly caused by a combination of pain, a mechanical limitation, and paresis/paralysis. When an older grey horse with melanomas on the predilection sites is submitted with pelvic limb lameness and abduction of the limb during the non supporting phase of the stride, a malignant melanoma in the pelvis is one of the differential diagnoses and a rectal examination should be performed. Diagnostic laparoscopy in the standing horse can be useful to confirm the provisional diagnosis.

Patient acceptability of a new 3.0 ml pre-filled insulin pen.

The objective of these two studies was to assess patient acceptance and feature preferences of the new Lilly 3.0 ml pre-filled pen. A total of 701 patients with diabetes mellitus, who required insulin, were treated for 4-6 weeks with the pre-filled pen. Patient acceptance and treatment preferences were assessed by a questionnaire completed at the end of the study period. Patients with type 1 or type 2 diabetes mellitus from South Africa (n = 371) and Croatia (n = 330) were enrolled in the study. The mean age was 51.6 years (range: 18-81), and gender was 359 males and 342 females. Prior to the study, patients in South Africa (SA) had used the Novo Actraphane (Novo Nordisk, Bagsvaerd, Denmark) pen set, and patients in Croatia (C) had used NovoPen 1 or 2 (Novo Nordisk, Bagsvaerd, Denmark) (38.8%), NovoPen 3 (Novo Nordisk, Bagsvaerd, Denmark) (28.8%), B-D Pen (Becton-Dickinson, Franklin Lakes, New Jersey, USA) (18.8%), needle/syringe (10.0%), oral hypoglycaemic agents (2.1%), or unknown (1.5%). The new Lilly 3.0 ml pre-filled pen features that were rated by respondents as good to excellent on a five-point rating scale included: cartridge visibility (C = 94%, SA = 83%), ease of dose correction (C = 92%, SA = 85%), dialling of the dose (C = 89%, SA = 81%), turning of the dose knob (C = 84%, SA = 82%) and attaching needles (C = 92%, SA = 78%). Most respondents (C = 78%, SA = 75%) preferred single-unit versus two-unit dosage increments. Overall, 76% of patients in Croatia and 80% in South Africa preferred the Lilly 3.0 ml pre-filled pen to their previous delivery device; 84% and 87% of patients, respectively, would recommend the pen to another patient. Also, the majority of patients in both trials rated the new Lilly 3.0 ml pre-filled pen as being more convenient and easier to use, and indicated that it represented a significant or modest improvement over their previous insulin injection method. The results of this study confirm that the new Lilly 3.0 ml pre-filled pen is widely accepted and preferred by patients using both reusable and pre-filled devices.

Physiological and psychological effects of active-alert hypnosis.

10 female physical education students were given posthypnotic suggestions alluding to economy of effort in exercise. These suggestions were affirmed under self-hypnosis over two weeks. Experimental subjects pedalled on an exercise bicycle for 20 min. at 60% of their maximal work capacity while listening to suggestions from a hypnotist. The Control group (n = 9) showed no differences between mean pretest and posttest scores on physical self-efficacy, trait anxiety, state anxiety, heart rate, blood pressure, and perceived rate of exertion. The average systolic blood pressure of the experimental group was the only positive significant difference between the pretest and posttest scores.

At convenience and systematic random sampling: effects on the prognostic value of nuclear area assessments in breast cancer patients.

This study compares the influence of two different nuclear sampling methods on the prognostic value of assessments of mean and standard deviation of nuclear area (MNA, SDNA) in 191 consecutive invasive breast cancer patients with long term follow up. The first sampling method used was 'at convenience' sampling (ACS); the second, systematic random sampling (SRS). Both sampling methods were tested with a sample size of 50 nuclei (ACS-50 and SRS-50). To determine whether, besides the sampling methods, sample size had impact on prognostic value as well, the SRS method was also tested using a sample size of 100 nuclei (SRS-100). SDNA values were systematically lower for ACS, obviously due to (unconsciously) not including small and large nuclei. Testing prognostic value of a series of cut off points, MNA and SDNA values assessed by the SRS method were prognostically significantly stronger than the values obtained by the ACS method. This was confirmed in Cox regression analysis. For the MNA, the Mantel-Cox p-values from SRS-50 and SRS-100 measurements were not significantly different. However, for the SDNA, SRS-100 yielded significantly lower p-values than SRS-50. In conclusion, compared with the 'at convenience' nuclear sampling method, systematic random sampling of nuclei is not only superior with respect to reproducibility of results, but also provides a better prognostic value in patients with invasive breast cancer.