A Practical Review of Functional MRI Anatomy of the Language and Motor Systems.

Functional MR imaging is being performed with increasing frequency in the typical neuroradiology practice; however, many readers of these studies have only a limited knowledge of the functional anatomy of the brain. This text will delineate the locations, anatomic boundaries, and functions of the cortical regions of the brain most commonly encountered in clinical practice-specifically, the regions involved in movement and language.

Pacemakers in MRI for the Neuroradiologist.

Cardiac implantable electronic devices are frequently encountered in clinical practice in patients being screened for MR imaging examinations. Traditionally, the presence of these devices has been considered a contraindication to undergoing MR imaging. Growing evidence suggests that most of these patients can safely undergo an MR imaging examination if certain conditions are met. This document will review the relevant cardiac implantable electronic devices encountered in practice today, the background physics/technical factors related to scanning these devices, the multidisciplinary screening protocol used at our institution for scanning patients with implantable cardiac devices, and our experience in safely performing these examinations since 2010.

Predictors of hemorrhage volume and disability after perimesencephalic subarachnoid hemorrhage.

OBJECTIVE: The determinants of subarachnoid hemorrhage (SAH) volume and an atypical pattern of blood are not clear. Our objective was to determine if reduced platelet activity on admission and abnormal venous drainage are associated with greater SAH volume. METHODS: We prospectively identified noncomatose patients with SAH without an identifiable aneurysm. We routinely measured platelet activity on admission and recorded aspirin use. SAH volumes were calculated with a validated technique. CT angiograms were reviewed by a certified neuroradiologist for venous drainage. Patients were followed for clinical outcomes through 3 months with the modified Rankin Scale (mRS). Data are Q1-Q3. RESULTS: There were 31 patients in the cohort. Thirty (97%) underwent an angiogram on admission, and 25 (81%) an additional delayed angiogram. SAH volume was lowest with normal venous drainage bilaterally (4.4 [3.7-16.4] mL) and higher with 1 (12.9 [3.7-20.4]) or 2 (20.9 [12.5-34.6] mL, p = 0.03) discontinuous venous drainages. Patients with reduced platelet activity had more SAH on the diagnostic CT (17.5 [10.6-20.9] vs 6.1 [2.3-15.3] mL) (p = 0.046). SAH volume was greater for patients requiring drainage for hydrocephalus (16.4 [11.5-20.5] vs 5.4 [2.7-16.4] mL) (p = 0.009). Outcomes at 3 months were generally excellent (median mRS = 0, no symptoms). CONCLUSIONS: Discontinuous venous drainage and reduced platelet activity were associated with increased SAH volume and hydrocephalus. These factors may explain thick SAH and reduce the need for repeated invasive imaging in such patients.

Posterior glottic stenosis with a calcified interarytenoid scar band: CT and laryngoscopic correlation.

A 52-year-old man with burn injuries and prolonged intubation developed PGS with hoarseness, dyspnea, and bilateral vocal cord immobility. On CT, a calcified interarytenoid scar band was identified, corresponding to an interarytenoid scar on laryngoscopy. Endoscopic laser lysis of the calcified scar band relieved the symptoms. We present laryngoscopic and CT findings of PGS with interarytenoid calcification along with the postlysis findings. The classification, clinical findings, imaging, and management of PGS are reviewed.

Improved detection of skull metastasis with diffusion-weighted MR imaging.

BACKGROUND AND PURPOSE: Metastasis to the skull is clinically important, but routine MR imaging offers moderate sensitivity for skull-metastasis detection in our experience. We sought to determine if diffusion-weighted MR imaging (DWI) could improve the detection of skull metastasis in patients with primary carcinomas that metastasized to bone compared with conventional MR imaging. MATERIALS AND METHODS: Seventy-five patients from the tumor registry of our institution with extracranial primary malignancy who had brain MR imaging with DWI and radionuclide bone scanning (RNBS, gold standard) within a 6-week interval were evaluated. Thirty-eight patients demonstrated increased radiopharmaceutical uptake on RNBS, consistent with skull metastasis of any size, and the remaining 37 were control subjects. Two readers correlated the DWI and conventional MR imaging with RNBS. RESULTS: The overall sensitivity of DWI for detection of skull metastases was 68.4%-71.1% (kappa=0.68) versus 42.1%-55.3% (kappa=0.65) for conventional MR imaging. Breast cancer (n=20) was detected with greatest sensitivity of 86.7%-93.3% (kappa=0.80) for DWI versus 60%-80% (kappa=0.5) for conventional MR imaging. Lung cancer (n=32) was detected with 63.6%-72.7% sensitivity (kappa=0.56), and prostate cancer (n=8) with 14.3% sensitivity (kappa=0.5) for DWI versus 27.3%-36.4% (kappa=0.81) and 14.3-42.9% (kappa=0), respectively, for conventional MR imaging. CONCLUSIONS: DWI is a useful sequence for identifying focal skull metastases for breast and lung malignancies and, compared with conventional MR imaging, provides improved detection of these lesions. DWI is insensitive for detecting skull metastases from prostate carcinoma.

Lasers and wound healing.

The advances in laser surgery over the past decade have been remarkable and have significantly altered the management of a host of dermatologic disorders. This article focuses on the CO2 laser as a cutting and vaporization tool and reviews the features that distinguish CO2 laser-induced wounds from those created by a scalpel. Tissue welding, wound management after skin treatment with the visible light lasers based on the principle of selective photothermolysis, as well as the controversial field of low-energy laser therapy (biostimulation) are also addressed.

Keloids and hypertrophic scars.

BACKGROUND: Keloids and hypertrophic scars are benign fibrous growths which usually occur after trauma in predisposed individuals. Their etiology, clinical manifestations and treatment are diverse. OBJECTIVE: The purpose of this article is to review the pertinent literature concerning keloids and hypertrophic scars as well as present my own perspective on the subject. It is my hope that the information contained herein will help both the dermatologist and dermatologic surgeon better understand and manage these vexing lesions. METHODS: Medline literature search as well as original material. RESULTS: There is no one right way to treat all keloids and hypertrophic scars. Treatment results have been variable. CONCLUSION: The management of keloids and hypertrophic scars can be difficult and frustrating for both patient and physician. A better understanding of keloid pathogenesis may lead to improved therapies by which keloid growth and regrowth may be obviated.

Adverse sequelae of venous hypertension.

Venous hypertension and venous ulcers are clinical entities that are expected to increase as the population ages. This article will review the current clinical and laboratory data pertinent to lipodermatosclerosis and venous ulcer development. An understanding of these putative pathophysiologic mechanisms may help the clinician to better diagnose and manage such patients.

Faster healing and less pain in skin biopsy sites treated with an occlusive dressing.

We prospectively studied 174 patients on whom 226 unsutured parallel incisional (shave) and 3-mm punch skin biopsies were performed. Two wound-care programs, occlusive dressing therapy and conventional therapy, were compared. The biopsy sites were evaluated after 1 or 2 weeks for healing, pain, and infection. We found that healing was unrelated to the indication for biopsy or the patients' age, gender, or race. Occlusive dressing therapy-treated shave biopsy sites were 3.83 times more likely to be healed than those treated with conventional therapy. Regardless of the treatment method, a facial shave biopsy site was 3.6 times more likely to be healed than a biopsy site in other locations. No punch biopsy site had healed after 1 week. At 2 weeks, only 7% and 36% of conventional therapy- and occlusive dressing therapy-treated punch biopsy sites, respectively, had healed. Pain at the biopsy site was six times more common in both shave and punch biopsy sites treated with conventional therapy. The absence of pain with occlusive dressing therapy was significant for both types of biopsy. One punch biopsy site treated with conventional therapy became infected, and one treated with occlusive dressing therapy was suspected of being infected. Forty patients, who had biopsy sites treated with both therapies, preferred occlusive dressing therapy over conventional therapy by a ratio of 3:1 because of ease of wound care and lack of pain. We conclude that occlusive dressing therapy may be the wound management of choice for shave biopsy sites. Since punch biopsy sites do not heal readily, it may be more appropriate to suture them, at least until therapies are developed that more effectively speed their healing.

Tretinoin accelerates healing after trichloroacetic acid chemical peel.

We conducted a double-blind, placebo-controlled, prospective, randomized study to assess the effects of tretinoin pretreatment on healing after trichloroacetic acid (TCA) chemical peel. Sixteen male patients (mean age, 67 years) with actinically damaged skin were treated daily with 0.1% tretinoin and placebo creams to the left and right halves of the face and the left and right forearms and hands, respectively, for 14 days prior to the 35% TCA peel. We subjectively noted that during the peel, "frosting" was more pronounced and uniform and occurred earlier in tretinoin-pretreated skin in 94% of the patients. Healed skin was measured planimetrically, and the healed area was determined with point stereology. Regardless of pretreatment, the face healed twice as fast as the forearm or hand. In all regions, the mean area healed was significantly greater in skin that had been pretreated with tretinoin. The differences between tretinoin and placebo, respectively, in healed skin were maximal after 5 days for the face (68% vs 52%), after 11 days for the forearms (72% vs 24%), and after 9 days for the hands (61% vs 29%). After 7 days, 75% of the tretinoin-pretreated hemifaces were completely healed, as opposed to 31% of the placebo-pretreated hemifaces. By visual inspection, we could not appreciate a cosmetic difference between tretinoin- and placebo-pretreated skin 2 weeks and 3 months after the TCA peel. We conclude that 0.1% tretinoin pretreatment for 2 weeks prior to the TCA peel will significantly speed healing, which may result in greater patient satisfaction. Patients presently being treated with tretinoin who later undergo a TCA peel might be expected to have similar results.

Childhood bullous pemphigoid. Clinical and immunologic features, treatment, and prognosis.

A 2 1/2-month-old female infant presented with multiple tense bullae on the hands and feet. Analysis of biopsy specimens confirmed our clinical impression of childhood bullous pemphigoid. Confirmatory data included type IV collagen mapping of the basement membrane zone, a readily available technique that helps distinguish childhood bullous pemphigoid from childhood epidermolysis bullosa acquisita. To our knowledge, our patient is the youngest described with childhood bullous pemphigoid, and we use this opportunity to review the literature and examine the clinical and immunologic features, treatment, and prognosis of this rare childhood immunobullous disorder.

Factor XIIIa in the hamartomas of tuberous sclerosis.

Factor XIII is a blood coagulation factor which may also be produced in an intracellular location. The 'a' subunit of this factor has been found in a number of different cell types and has been shown to stimulate the proliferation of fibroblasts in vitro. We have examined cutaneous, central nervous system and renal lesions from persons with tuberous sclerosis using a standard immunohistochemical assay to see if factor XIIIa is expressed in these hamartomatous growths. We found factor XIIIa in most of the stromal cells composing the skin lesions of tuberous sclerosis as well as in cells of subependymal giant cell astrocytoma of the brain and the stromal cells in renal angiomyolipoma. Expression of factor XIIIa may be of significance in the formation of fibrous growths in tuberous sclerosis.

Factor XIIIa is expressed by fibroblasts in fibrovascular tumors.

Factor XIIIa (FXIIIa), a blood and intracellularly produced coagulation factor, has been found in a variety of cell types including fibroblast-like mesenchymal cells, and has been shown to stimulate the proliferation of fibroblasts and some neoplastic cells in vitro. We have already shown that the dendritic fibroblasts composing the fibrous papule contain this factor. We hypothesized that histopathologically similar fibrovascular tumors may also express FXIIIa and, in this report, show that the large stellate fibroblasts found in acquired digital fibrokeratomas, angiofibromas (adenoma sebaceum of Pringle), and oral fibroma (oral fibrous hyperplasia) also express FXIIIa. We postulate that FXIIIa, possibly acting as a growth factor, may be a common denominator in the pathogenesis of these tumors. Another possibility is that these tumors may be the consequence of a local overproduction of FXIIIa in response to an, as yet, unidentified stimulus.

Clinical parameters and transcutaneous oxygen measurements for the prognosis of venous ulcers.

Few data exist on the prognosis of venous ulcers. We therefore prospectively studied 14 patients with severe venous ulcers for up to 18 months and examined various possible prognostic factors, including transcutaneous oxygen tension (TcPO2) measurements of skin next to the ulcers. The ulcers had been present for a mean duration of 15.6 months before referral to our clinic. During the study only four patients (29%) had ulcers that were healed with conservative management consisting of topical and systemic antibiotics and conventional and occlusive dressings. We observed that the number of ulcers, their duration before admission to the study, and the extent of lipodermatosclerosis were more pronounced in the unhealed group. For all patients the mean ulcer TcPO2 level (5.6 +/- 1.5 mm Hg, mean +/- standard error) was significantly reduced when compared with the control chest site (62.4 +/- 2.1 mm Hg) (p less than 0.001; paired t test). The mean ulcer TcPO2 was not significantly different between the healed (4.5 +/- 2.0 mm Hg) and unhealed groups (6.1 +/- 2.0 mm Hg). We conclude that TcPO2 levels may not be predictive of the response to therapy in venous ulcers. TcPO2 levels may be markedly reduced, but even extremely low levels are not incompatible with healing.

Ulcerated edematous limbs: effect of edema removal on transcutaneous oxygen measurements.

We studied the effect of edema removal on transcutaneous oxygen tension (TcPO2) in eight patients with leg ulcers. An external pneumatic compression device was effective in removing edema from the ulcerated limbs over a 5-day course of treatment, at which time all treated limbs were clinically free of edema. TcPO2 levels at room air at the ulcer site were markedly reduced when compared with the control chest site, both before and after external pneumatic compression device therapy (p less than 0.001). Edema removal, however, did not significantly alter TcPO2 values (p greater than 0.9). No significant positional effects on TcPO2 values were noted with patients supine, sitting, or with the affected limbs elevated. Five patients (63%) had increased TcPO2 values adjacent to the ulcer site when receiving supplemental oxygen. For these patients, TcPO2 values increased after oxygen inhalation, both before and after edema removal (p less than 0.05). We conclude that TcPO2 values are markedly reduced in ulcerated edematous limbs. Edema, however, may not constitute a barrier to oxygen diffusion through the skin and does not account for the low TcPO2 values in the ulcerated edematous limb. Therefore the positive therapeutic effect of removing edema is unlikely to be related to better oxygenation of the tissues.