[Anterior clinoid process mucocele causing optic nerve compression].

A mucocele is a collection of mucus lined by mucus-secreting epithelium of a paranasal sinus. The anterior clinoid process may become pneumatized during the development of the skull base. Rarely, an anterior clinoid process mucocele may form in this air space. We report a patient with anterior clinoid process mucocele who presented with visual loss and limited motility in the affected eye, and underwent surgery to decompress the orbital apex and optic nerve. We also review the literature regarding this rare diagnosis.

Antral computerized tomography pre-operative evaluation: relationship between mucosal thickening and maxillary sinus function.

OBJECTIVES: to assess the correlation between maxillary sinus inferior mucosal thickening and sinus outflow obstruction. MATERIAL AND METHODS: the study included 280 computerized tomography (CT) scans (560 maxillary sinuses). CT aimed to assess sinusitis; trauma to the face and intubated patients were excluded. Mucosal thickening was graded as < 5 mm (1), < 10 mm (2), < 15 mm (3), < 20 mm (4) and > 20 mm (5), and classified by appearance as normal, rounded, circumferential, irregular, or complete. Maxillary sinus outflow was classified as patent or obstructed. RESULTS: mucosal thickening was found in 36.1% of the maxillary sinuses, graded as 31.2% (1), 34.2% (2), 12.9% (3), 5.4% (4) and 16.3% (5), and classified as rounded (11.8%), irregular (10.4%), circumferential (8.8%) and complete (5.2%). Sinus outflow was obstructed in 15% of the scans. Mucosal thickening of < 5 mm (11.1%), < 10 mm (36.2%) and > 10 mm (74.3%) was associated with sinus obstruction (P<0.0001). Rounded (6.1%), circumferential (55.2%), irregular (38.8%) and complete (100%) mucosal appearances were associated with sinus obstruction (P<0.001). When statistically combined, a substantial risk for sinus obstruction was observed with irregular mucosal appearance of > 5 mm (56.5% for grade 2 up to 82.6% for grades 3-5) and circumferential appearance (21.4% for grade 1 up to 100% for grades 3-5). A low risk for obstruction was found with the rounded appearance (mean 6.1%). CONCLUSIONS: irregular (> 5 mm), circumferential and complete mucosal appearance are associated with an increased risk for sinus outflow obstruction and an ENT consultation is recommended. A rounded mucosal appearance of any grade is associated with a low risk for sinus obstruction. Routine CT scans, including the maxillary sinus ostium, are recommended.

Selective impairment of prediction error signaling in human dorsolateral but not ventral striatum in Parkinson's disease patients: evidence from a model-based fMRI study.

Animal studies have found that the phasic activity of dopamine neurons during reward-related learning resembles a "prediction error" (PE) signal derived from a class of computational models called reinforcement learning (RL). An apparently similar signal can be measured using fMRI in the human striatum, a primary dopaminergic target. However, the fMRI signal does not measure dopamine per se, and therefore further evidence is needed to determine if these signals are related to each other. Parkinson's disease (PD) involves the neurodegeneration of the dopamine system and is accompanied by deficits in reward-related decision-making tasks. In the current study we used a computational RL model to assess striatal error signals in PD patients performing an RL task during fMRI scanning. Results show that error signals were preserved in ventral striatum of PD patients, but impaired in dorsolateral striatum, relative to healthy controls, a pattern reflecting the known selective anatomical degeneration of dopamine nuclei in PD. These findings support the notion that PE signals measured in the human striatum by the BOLD signal may reflect phasic DA activity. These results also provide evidence for a deficiency in PE signaling in the dorsolateral striatum of PD patients that may offer an explanation for their deficits observed in other reward learning tasks.

Acute esotropia after epidural anesthesia.

BACKGROUND: Cranial nerve palsy after dural puncture is an uncommon complication. The sixth cranial nerve is the most commonly affected because of its long intracranial course. We report a case of acute comitant esotropia that occurred after unintentional dural puncture. CASE: A young woman presented with acute onset comitant esotropia 1 week after epidural anesthesia for a normal vaginal delivery during which the dura was unintentionally punctured. Magnetic resonance imaging revealed diffuse pachymeningeal enhancement, typically seen after dural puncture. Resolution was spontaneous. CONCLUSION: Puncture of the dura should be considered when acute strabismus is diagnosed shortly after epidural anesthesia.

Systemic corticosteroids for allergic fungal rhinosinusitis and chronic rhinosinusitis with nasal polyposis: a comparative study.

OBJECTIVES: To compare the effect of preoperative high-dose systemic corticosteroids on the radiographic and endoscopic appearance of allergic fungal rhinosinusitis (AFRS) and chronic rhinosinusitis with nasal polyposis (CRSwNP). STUDY DESIGN AND SETTING: Eight AFRS and 10 CRSwNP patients underwent computed tomographic (CT) scans and then received preoperative 1 mg/kg prednisone for 10 days. CT scans were repeated 1 day before surgery and compared with pretreatment scans (Lund-MacKay radiologic scoring system). The endoscopic appearance was recorded intraoperatively. RESULTS: The score dropped from 16 (66.4%) to 4.75 in the AFRS group and from 18.4 (23%) to 14.1 in the CRSwNP group (P=0.0064). Intraoperatively, most sinus mucosal surfaces appeared normal in the AFRS patients but were markedly edematous in the CRSwNP patients. CONCLUSION: Radiographic response of AFRS to systemic corticosteroids is significantly greater compared with CRSwNP. This finding is supported by endoscopic observation.

Sonographic features of senile scleral calcification.

BACKGROUND AND OBJECTIVE: To describe the sonographic features of senile scleral calcification using ultrasound biomicroscopy. PATIENTS AND METHODS: Four patients in whom senile scleral calcifications were found incidentally on computed tomography studies underwent ultrasound biomicroscopy examination. RESULTS: The senile scleral calcification was bilateral in three patients and unilateral in one patient. In all patients, the calcified material created the anterior shadowing typical of calcified lesions. The ultrasound biomicroscopy study localized the senile scleral calcification to the subconjunctival layer, superficially above the sclera, and anterior to the horizontal muscles. CONCLUSIONS: This is the first description of the ultrasound biomicroscopy features of senile scleral calcification. Ultrasound biomicroscopy may serve as a good tool for the accurate localization of the plaque.

Palpitations: could they be neurogenic? A case report.

BACKGROUND: Palpitations usually occur in patients with arrhythmias of cardiac origion, in conditions associated with increased catecholamine levels, and in psychiatric disorders. A rare etiology of palpitations is seizures with autonomic features. REVIEW SUMMARY: We report a 24-year-old man with a several-week history of episodic palpitations, weakness, dizziness, and presyncopal phenomena. Subsequent events included loss of consciousness, with postevent confusion and tonic movements. A low-grade astrocytoma was diagnosed in the right frontal lobe. CONCLUSION: This case emphasizes the importance of detailed history in the diagnosis of epilepsy.

A targeted endoscopic approach to chronic isolated frontal sinusitis.

OBJECTIVE: Chronic isolated frontal sinusitis occurs infrequently. In this condition, most of the ethmoid cells are well aerated and the frontal sinus is involved secondary to anatomical obstruction or inflammatory changes confined to the frontal recess. The purpose of this study was to evaluate a targeted endoscopic technique where standard anterior ethmoidectomy is unnecessary in the treatment of chronic isolated frontal sinusitis. STUDY DESIGN AND SETTING: This retrospective study was conducted in a large university-affiliated hospital and included 11 patients with chronic isolated frontal sinusitis who underwent endoscopic sinus surgery limited to the frontal sinus outflow. The ethmoid bulla was untouched in all cases. Follow-up continued for 19 to 40 months (mean 28.6 months). RESULTS: Frontal sinus outflow patency was verified in 9 patients (81.8%). Nine patients, including one with an apparent nonpatent frontal ostium, reported improvement. Two patients-one of whom had a patent frontal ostium-reported no improvement. There were no complications. CONCLUSION: Chronic isolated frontal sinusitis can be effectively treated in selected cases by a targeted endoscopic procedure, limited to reestablishment of frontal sinus outflow. EBM RATING: C-4.

Necrotizing Fasciitis of the Skull Base and Neck in a Patient with AIDS and Non-Hodgkin's Lymphoma.

Necrotizing fasciitis is a rapidly progressing, life-threatening soft tissue bacterial infection found more frequently in immunocompromised subjects and rarely in the head and neck. We report a rare case of a patient with acquired immunodeficiency syndrome (AIDS) and non-Hodgkin's lymphoma (NHL) who presented with a high fever and supraorbital cellulitis 1 week after undergoing chemotherapy. He received intravenous antibiotic therapy but soon developed dyspnea and trismus with rapid extension of the cellulitis to the face, ipsilateral infratemporal fossa (ITF), and bilateral neck. An awake tracheotomy was followed by surgical exploration and drainage and debridement of the supraorbital and ITF areas, parotid gland, and bilateral neck. He received intravenous antibiotic therapy and the surgical wound was regularly debrided for 10 days. Following a gradual recovery, the patient was discharged 2 weeks later. Early antibiotic therapy, wide surgical exploration, and a secured airway are the therapeutic mainstay for necrotizing fasciitis of the skull base and neck.

Stafne bone cavity--magnetic resonance imaging.

A case of Stafne bone cavity (SBC) affecting the body of the mandible of a 51-year-old female is reported. The imaging modalities included panoramic radiograph, computed tomography (CT) and magnetic resonance (MR) imaging. Panoramic radiograph and CT were able to determine the outline of the cavity and its three dimensional shape, but failed to precisely diagnose the soft tissue content of the cavity. MR imaging demonstrated that the bony cavity is filled with soft tissue that is continuous and identical in signal with that of the submandibular salivary gland. Based on the MR imaging a diagnosis of SBC was made and no further studies or surgical treatment were initiated. MR imaging should be considered the diagnostic technique in cases where SBC is suspected. Recognition of the lesion should preclude any further treatment or surgical exploration.

4D MRI for the Localization of Parathyroid Adenoma: A Novel Method in Evolution.

The sestamibi scan (MIBI) and ultrasound (US) are used for preoperative localization of parathyroid adenoma (PTA), with sensitivity as high as 90%. We developed 4-dimensional magnetic resonance imaging (4D MRI) as a novel tool for identifying PTAs. Eleven patients with PTA were enrolled. 4D MRI from the mandible to the aortic arch was used. Optimization of the timing of image acquisition was obtained by changing dynamic and static sequences. PTAs were identified in all except 1 patient. In 9 patients, there was a complete match between the 4D MRI and the US and MIBI, as well as with the operative finding. In 1 patient, the adenoma was correctly localized by 4D MRI, in contrast to the US and MIBI scan. The sensitivity of the 4D MRI was 90% and after optimization, 100%. Specificity was 100%. We concluded that 4D MRI is a reliable technique for identification of PTAs, although more studies are needed.

Loss of function of PCDH12 underlies recessive microcephaly mimicking intrauterine infection.

OBJECTIVE: To identify the genetic basis of a recessive syndrome characterized by prenatal hyperechogenic brain foci, congenital microcephaly, hypothalamic midbrain dysplasia, epilepsy, and profound global developmental disability. METHODS: Identification of the responsible gene by whole exome sequencing and homozygosity mapping. RESULTS: Ten patients from 4 consanguineous Palestinian families manifested in utero with hyperechogenic brain foci, microcephaly, and intrauterine growth retardation. Postnatally, patients had progressive severe microcephaly, neonatal seizures, and virtually no developmental milestones. Brain imaging revealed dysplastic elongated masses in the midbrain-hypothalamus-optic tract area. Whole exome sequencing of one affected child revealed only PCDH12 c.2515C>T, p.R839X, to be homozygous in the proband and to cosegregate with the condition in her family. The allele frequency of PCDH12 p.R839X is <0.00001 worldwide. Genotyping PCDH12 p.R839X in 3 other families with affected children yielded perfect cosegregation with the phenotype (probability by chance is 2.0 × 10(-12)). Homozygosity mapping revealed that PCDH12 p.R839X lies in the largest homozygous region (11.7 MB) shared by all affected patients. The mutation reduces transcript expression by 84% (p < 2.4 × 10(-13)). PCDH12 is a vascular endothelial protocadherin that promotes cellular adhesion. Endothelial adhesion disruptions due to mutations in OCLN or JAM3 also cause congenital microcephaly, intracranial calcifications, and profound psychomotor disability. CONCLUSIONS: Loss of function of PCDH12 leads to recessive congenital microcephaly with profound developmental disability. The phenotype resembles Aicardi-Goutières syndrome and in utero infections. In cases with similar manifestations but no evidence of infection, our results suggest consideration of an additional, albeit rare, cause of congenital microcephaly.

White matter changes in multiple sclerosis: correlation of q-space diffusion MRI and 1H MRS.

OBJECTIVE: To explore the diagnostic usefulness of high b-value diffusion magnetic resonance brain imaging ("q-space" imaging) in multiple sclerosis (MS). More specifically, we aimed at evaluating the ability of this methodology to identify tissue damage in the so-called normal-appearing white matter (NAWM). DESIGN: In this study we examined the correlation between q-space diffusion imaging and magnetic resonance spectroscopy (MRS)-based two-dimensional 1H chemical shift imaging. Eight MS patients with different degree of disease severity and seven healthy subjects were scanned in a 1.5-T magnetic resonance imaging (MRI) scanner. The MRI protocol included diffusion tensor imaging (DTI) (with bmax of 1000 s/mm2), high b-value diffusion-weighted imaging (with bmax of 14,000 s/mm2) and 2D chemical shift imaging. The high b-value data set was analyzed using the q-space methodology to produce apparent displacement and probability maps. RESULTS: We found that the q-space diffusion displacement and probability image intensities correlated well with N-acetylaspartate levels (r=.61 and .54, respectively). Furthermore, NAWM that was abnormal on MRS was also found to be abnormal using q-space diffusion imaging. In these areas, the q-space displacement values increased from 3.8+/-0.2 to 4.6+/-0.6 microm (P<.02), the q-space probability values decreased from 7.4+/-0.3 to 6.8+/-0.3 (P<.002), while DTI revealed only a small, but still significant, reduction in fractional anisotropy values from 0.40+/-0.02 to 0.37+/-0.02 (P<.05). CONCLUSION: High b-value diffusion imaging can detect tissue damage in the NAWM of MS patients. Despite the theoretical limitation of this method, in practice it provides additional information which is clinically relevant for detection of tissue damage not seen in conventional imaging techniques.

Surgical management of parapharyngeal space tumors: a 10-year review.

OBJECTIVE: The purpose of this article is to describe the diagnostic evaluation and surgical approaches to parapharyngeal space tumors in a tertiary referral center. STUDY DESIGN AND SETTING: The study is a retrospective review of 47 patients diagnosed with tumors of the parapharyngeal space (12 with malignant diseases and 35 with benign lesions) and surgically treated during a 10-year period. The transcervical (40%) and the transcervical-transparotid approaches (46%) were the most commonly performed surgical procedures followed by the orbitozygomatic-middle fossa approach (12%) and the transmandibular approach (2%). RESULTS: The surgical procedures were uneventful and there were no postoperative mortalities. Complications were rare; the most common was transient facial nerve paralysis (5 patients). After an average follow-up of 35 months, only 1 of 35 patients with benign diseases had a recurrence 5 years following transcervical resection of a pleomorphic adenoma. Of 12 patients with malignant tumors, 5 (42%) are alive with no evidence of disease. The sensitivity of preoperative fine needle aspiration biopsy (n = 23 patients) was 87% for detection of malignant disease and specificity was 100%. CONCLUSIONS: Most benign parapharyngeal space tumors can be removed surgically with a low rate of complications and recurrence. Malignant neoplasms, however, carry an ominous prognosis and a low rate of disease-free survival. Fine needle aspiration may be helpful in preoperative diagnostic evaluation of patients with parapharyngeal space tumors.

A Novel Radiographic Sign and a New Classifying System in Mastoiditis-Related Epidural Abscess.

OBJECTIVE: To describe a novel radiographic sign ("halo") and a new classification method of an evolving perisigmoid epidural abscess and present its correlation with intraoperative findings. STUDY DESIGN: Retrospective and prospective cohort study in a tertiary academic children's hospital. METHODS: The retrospective arm (15 children) was conducted between 1998 and 2007 and the prospective arm (11 children) between 2008 and 2013. The computerized tomographic appearance of the perisigmoid region was classified into four groups: Class I, normal; Class II, smooth halo; Class III, nodular halo 4 mm or less in diameter; and Class IV, gross nodular halo more than 4 mm in diameter. Intraoperative findings of the perisigmoid region were compared with the preoperative scan results. RESULTS: The correlation between preoperative imaging and intraoperative findings of the retrospective arm was highly significant (p = 0.007). The correlation between the preoperative imaging studies and intraoperative findings of the prospective arm was also highly significant (p = 0.005). The interobserver agreement for the proposed classification method was high (Cohen kappa score, 0.76; weighted kappa score, 0.84). CONCLUSION: A novel radiographic sign ("halo") and a new classification method for an evolving perisigmoid epidural abscess in acute mastoiditis are described. A thin and smooth halo sign is not indicative of a true abscess formation. Gross perisigmoid granular changes, however, are highly suggestive of an epidural abscess that warrants surgical intervention.

MR imaging appearance of frontal sinus barotrauma.

We present the case of a flight passenger who experienced acute and severe headache during landing. MR imaging was performed because the patient had a history of vascular malformation and revealed an incidental venous angioma. A mass lesion in the frontal sinus, consistent with submucosal hematoma secondary to barotrauma, was thought to be the cause of the headache. To our knowledge, this is the first case of sinus barotrauma described in the radiologic literature and the first to describe the associated MR imaging findings.

Gray-white matter discrimination--a possible marker for brain damage in heat stroke?

INTRODUCTION/OBJECTIVE: Heat stroke (HS) is a common medical emergency which carries high morbidity and morality. This study was designed to describe the pattern of central nervous system (CNS) changes as detected by brain CT scan in a case series of six patients suffering from classical and exertional HS. METHODS AND PATIENTS: All the patients were admitted in critical condition during the heat wave in the summer of 1999 in Israel. Each was in deep coma with a measured core temperature of over 40 degrees C upon admission to the emergency department. RESULTS: Aggressive cooling measures decreased the core temperature to <38 degrees C within 30 min following admission. Two patients (33.3%) died. One of the survivors remained in a vegetative state. Brain CT studies carried out within 4 days of admission in all the patients revealed severe loss of gray-white matter discrimination (GWMD) without signs of acute bleed or significant focal lesion, findings that persisted in repeated brain CTs in one patient who remained in a vegetative state. DISCUSSION AND CONCLUSIONS: Loss of GWMD may represent an early and sensitive indication of severe brain damage in patients with severe HS. Further studies in larger groups of patients are warranted in order to determine whether the appearance of GWMD in brain CTs of patients with HS has prognostic value.

Aggressive intracranial dural arteriovenous fistula presenting with cerebrospinal fluid rhinorrhea: case report.

OBJECTIVE: This is the first report of an aggressive dural arteriovenous fistula presenting with rhinorrhea. It demonstrates the importance of recognizing increased intracranial pressure, and its underlying cause, as the predisposing factor to a spontaneous cerebrospinal fluid leak because this carries implications for management. CLINICAL PRESENTATION: Ten years after minor trauma and directly after an intercontinental flight, a 43-year-old woman presented with rhinorrhea. Right-sided pulsatile tinnitus had been present for the past 9 years. Imaging demonstrated an intracranial dural arteriovenous fistula of the right transverse sinus with cortical venous reflux. Magnetic resonance imaging findings indicated long-standing increased intracranial pressure. INTERVENTION: The fistula was treated by endovascular means, using both transvenous and transarterial approaches, which led to immediate relief of the tinnitus and resolution of the rhinorrhea within 4 days. CONCLUSION: A dural arteriovenous fistula should be included in the differential diagnosis of underlying causes of increased intracranial pressure when examining a patient with a cerebrospinal fluid leak. Treatment of the fistula should precede attempts to treat the rhinorrhea, especially if the fistula has cortical venous reflux.