Diagnostic value of cervical discography in the management of cervical discogenic pain.

We did a retrospective analysis of patients who had a total of 46 cervical discs examined by cervical discography and then evaluated the postoperative results of 14 of the 16 patients who underwent cervical spine fusion at those levels in accordance with the results of our discograms. The average symptomatic period prior to discography was 12 months, and cervical discogenic pain was successfully localized in all 16 patients. Immediately post-cervical discectomy and anterior fusion, subjectively, all 14 patients had good to excellent results, and after a mean follow-up of 6.5 (1.5 to 14) months, 11 patients (78.6%) continued with good to excellent results and three patients (21.4%) developed related pain patterns. Thus, cervical discography, in a "select group" of patients with chronic intractable neck pain but negative or indeterminate imaging findings who are being considered for surgical intervention, can help localize the symptomatic level and potentially benefit the patients by surgical intervention.

Brain morphometric analysis in neurofibromatosis 1.

RATIONALE AND OBJECTIVES: To investigate the relationships between brain and skull base growth in patients with neurofibromatosis 1 (NF1) compared with healthy control subjects using brain magnetic resonance imaging (MRI) for morphometric analysis. METHODS: Evaluated patients included children who underwent T1- and T2-weighted or dual-echo proton density axial and T1-weighted sagittal brain MRI from January 1, 1988, to December 31, 1995. Study subjects (n = 27) received a diagnosis of NF1 by accepted National Institutes of Health clinical criteria and were compared with an age- and sex-matched control group (n = 43). Twenty-four predetermined ventricular and brain parenchymal dimensions and area calculations were evaluated. Data were analyzed using 2-tailed t tests, chi2 analysis, analysis of variance, and analysis of covariance adjusted for age and sex. Correlational analyses with respect to subject type and age were performed separately. RESULTS: There were 27 patients (20 boys, aged 1.0-17.7 years; mean age, 8.8 years) and 43 controls (22 boys, aged 0.1-17.7 years; mean age, 5.9 years). The mean ages between groups (boys, girls, and totals) were not statistically different. Significant differences were appreciated for 6 of 24 measures. Patients with NF1 had a significantly larger bicaudate width (P = .002), biatrial width (P<.001), and biparietal diameter (P = .003), but not hemispheric length. They also had significantly increased iter measures (P = .004), descending sigmoid sinus (P<.001), and an age-specific increase in brainstem height (P = .03) not seen in controls. CONCLUSIONS: Patients with NF1 experience dynamic changes in brain morphometry, resulting in a predominant lateral volume expansion of the supratentorial compartment and an increasing velocity of brainstem growth as they age. These data underscore brain-region-specific parenchymal overgrowth potential.

Magnetic resonance imaging lesion analysis in neurofibromatosis type 1.

OBJECTIVE: To define the evolution of identified high-signal brain parenchymal lesions on magnetic resonance imaging (MRI) studies in patients with neurofibromatosis type 1 (NF-1). DESIGN: A cohort of patients with NF-1 who underwent MRI were identified prospectively and their imaging studies analyzed. PATIENTS: All referred patients with NF-1 (as defined by National Institutes of Health consensus criteria), who had undergone imaging with MRI were eligible. Of 123 patients with NF-1 whose conditions were evaluated, 30 patients had undergone 59 MRIs. There were 22 males and 8 females, aged 1 to 53 years with mean age of 12.5 years. Two groups of patients were identified, those with brain lesions (WBL) and those with no brain lesions. All initial and subsequently obtained MRIs from the WBL group were analyzed and tallied for number, size, and location of lesions over serial studies. RESULTS: Of the 19 patients with WBL, lesions were in hemispheres in 19 patients, and in the brainstem and the cerebellum in 10 patients each, respectively. Lesions were located in the cerebellum and globus pallidus most often (87 of 129 lesions). Of the patients with WBL having serial studies, a total of 97 lesions equaling 197 units (mean, 2.03 units per lesion) were identified at initial study. Follow-up evaluation (interval, 0.5-4.5 years; mean, 2.3 years), showed a decrease in both total number of lesions (68 [-29%]) and size (132 units; mean, 1.86 units per lesion [-33%]). Importantly, brainstem lesions increased in both number (+36%) and size (+6.4%) over the same intervals in 7 of 13 patients with WBL studied serially, whereas hemispheric and cerebellar lesions were more evanescent. CONCLUSIONS: High-signal T2 lesions on MRI in patients with NF-1 evolve over time. The evolution of the NF-1 lesion is region specific and may relate to preferential region-specific effects of the NF-1 gene product.

Grebe syndrome: clinical and radiographic findings in affected individuals and heterozygous carriers.

Grebe syndrome is a recessively inherited acromesomelic dysplasia. We studied, clinically and radiographically, 10 affected individuals, originating from Bahia, Brazil. The phenotype is characterized by a normal axial skeleton and severely shortened and deformed limbs, with a proximo-distal gradient of severity. The humeri and femora were relatively normal, the radii/ulnae and tibiae/fibulae were short and deformed, carpal and tarsal bones were fused, and several metacarpal and metatarsal bones were absent. The proximal and middle phalanges of the fingers and toes were invariably absent, while the distal phalanges were present. Postaxial polydactyly was found in several affected individuals. Several joints of the carpus, tarsus, hand, and foot were absent. Heterozygotes presented with a variety of skeletal manifestations including polydactyly, brachydactyly, hallux valgus, and metatarsus adductus. Grebe syndrome is caused by a missense mutation in the gene encoding cartilage-derived morphogenetic protein-1.

Omental infarction: report of three cases and review of the literature.

Omental Infarction, the end result of impaired perfusion to the greater omentum, is a rare entity (JBCM Puylaert, Radiology 1992;185:169-172). We recently encountered three patients in whom computed tomography (CT) showed the characteristic findings of omental infarction. The diagnosis was subsequently confirmed intraoperatively and pathologically in two of the cases. The third case showed partial resolution on follow-up computed tomography. All three cases are presented with a brief review of the literature.

Concurrence of Graves' disease and dysplastic cerebral blood vessels of the moyamoya variety.

We describe two Caucasian women with the concurrence of Graves' disease and the moyamoya phenomenon (radiological evidence of collateral cerebral blood vessels like "puffs of smoke" due to cerebrovascular occlusive disease). One patient presented with acute cerebrovascular ischemia due to Moyamoya disease shortly after radioactive iodine therapy for Graves' disease and the second presented with Graves' disease 10 years after being diagnosed with moyamoya dysplastic cerebral vessels. The optimal treatment of hyperthyroidism in these patients is unknown; however, careful control of the hyperthyroidism by any modality seems reasonable. Our limited experience suggests that antithyroid drugs and radioactive iodine therapy are rational options. Thyroidectomy appears to be a safe therapeutic alternative, although long-term efficacy may be difficult to assure. Both of our patients had to be treated twice for hyperthyroidism. Whether Graves' disease and Moyamoya coexist because of an aggressive autoimmune mechanism is a concept that remains to be settled.

Dosimetry and cost of imaging osseointegrated implants with film-based and computed tomography.

Thermoluminescent dosimeters were used to measure radiation doses at craniofacial sites in a tissue-equivalent phantom during film-based multidirectional tomography with the Tomax Ultrascan (Incubation Industries, Ivyland, Pa.) and during computed tomography with the Elscint Excel 2400 (Elscint Corp., Tel Aviv, Israel). Mean absorbed doses for presurgical mandibular and maxillary canine and molar implant assessments were converted to equivalent doses, which were then multiplied by published weighting factors and summed to give effective doses. The computed tomography device consistently delivered higher doses than the Tomax Ultrascan to all anatomic locations; the differences were most pronounced when only one or two implant sites were evaluated. The reasons for the dose disparities are considered both anatomically and procedurally. A survey of examination cost revealed film-based multidirectional tomography to be less expensive than computed tomography.

Periventricular heterotopia: an X-linked dominant epilepsy locus causing aberrant cerebral cortical development.

Periventricular heterotopia (PH) involves dramatic malformations of the human cerebral cortex. Here we show that PH is closely linked to markers in distal Xq28 (maximal two-point lod score = 4.77 for F8C at theta = 0; maximal multipoint lod score = 5.37), so that affected females are obligatory mosaics for the mutation; that PH is lethal to at least some affected males; that PH malformations consist of well-differentiated cortical neurons filling the adult subependymal zone; and that individuals with PH are at high risk for epilepsy, though they have no other neurological or external stigmata. The PH gene may represent an important epilepsy susceptibility locus in addition to playing a key role in normal cortical development.

Sensitivity of percutaneous endoscopy compared with ultrasonography in the detection of residue or mucosal lesions after topical gallbladder stone dissolution.

BACKGROUND: Early gallstone recurrence in some patients after "successful" percutaneous topical dissolution may be due to residual debris. An endoscope small enough to be introduced without dilating the existing percutaneous track was used for gallbladder examination after stone dissolution. METHODS: The sensitivity of gallbladder endoscopy was compared with ultrasonography and double-contrast cholecystography for the detection of residual debris or mucosal lesions in 18 patients who underwent percutaneous topical dissolution. All examinations were performed before catheter removal and after the gallbladder was deemed stone-free by the traditionally employed technique of single-contrast cholecystography. RESULTS: Residual debris was detected in only one patient by ultrasonography and in none of the 18 patients by double-contrast cholecystography, yet endoscopy showed stone fragments ranging from 1 to 3 mm in 13 of the 18 patients. In all these patients, catheter repositioning and additional solvent perfusion resulted in elimination of the debris as assessed endoscopically. Two patients had endoscopically detected erosions. Double-contrast fluoroscopy found only one of these, whereas ultrasonography detected neither. CONCLUSIONS: Percutaneous gallbladder endoscopy is a more sensitive imaging modality for the detection of residual stone debris or mucosal lesions after gallstone dissolution.

Brain morphometric analysis in achondroplasia.

RATIONALE AND OBJECTIVES: We undertook an MRI brain morphometric analysis to investigate the relationships between brain and skull base growth and clinical function in patients with achondroplasia as compared to normal controls. METHODS: Patients selected for evaluation included pediatric patients who underwent T1 and T2 or dual-echo, proton-density axial T1- and T2-weighted and T1 sagittal brain MRI during 1988 to 1992. Study subjects (n = 11) were diagnosed with achondroplasia by clinical and radiologic criteria and compared to an age- and gender-matched control group (n = 25). Twenty-four predetermined ventricular and brain parenchymal dimensions and area calculations were evaluated. Data were analyzed using two-tailed t tests, chi-squared analysis, ANOVA, and ANCOVA, adjusting for age and sex. Correlational analyses with respect to subject type and age were done separately. RESULTS: There were 36 patients (11 subjects with 15 MRI examinations, mean age 2.3 years, and 25 controls with 26 MRI examinations, mean age 3.0 years). Significant differences existed for 11/17 measures. Achondroplasts had a significantly larger bifrontal width (p < 0.0001), bicaudate width (p < 0.0001), frontal horn diagonal length (p < 0.05), biatrial width (p < 0.0001), biparietal diameter (p < 0.05), and iter to incisural line distance (p < 0.0001). Achondroplasts had significantly smaller frontal lobe depths (p < 0.01), optic tract angles (p < 0.0001), foramen magnum diameters (p < 0.0001), and sinojugular transition zones (p < 0.05). There were no differences in brainstem heights or fourth ventricular widths between achondroplasts and controls. Furthermore, with respect to age, frontal lobe depth was smaller when compared to controls and the descending sigmoid sinus area became increasingly larger. CONCLUSIONS: Achondroplastic subjects experience dynamic changes in brain morphometry resulting in a rostral displacement of the brainstem with gradual compression of the frontal lobes due to enlargement of the supratentorial ventricular spaces commensurate with an increase in venous sinus distension.

Percutaneous removal of infected permanent pacemaker leads using a simple coaxial dilating system.

A simple traction-countertraction technique using common and readily available materials was successfully used to remove infected pacemaker leads from two patients. The specific methodology is presented. Although somewhat technically demanding, this approach appears safe and cost-effective. This method provides another way to remove pacemaker leads without resorting to thoracotomy.

Accelerated hypertension with encephalopathy due to an isolated dissection of a renal artery branch vessel.

Typical causes of renovascular hypertension include intramural atherosclerotic lesions of the main renal arteries or their branches and fibromuscular dysplasia of the renal arterial wall with luminal narrowing. We report a patient with new-onset, accelerated hypertension (blood pressure 220/140 mm Hg, status epilepticus, retinal hemorrhages) secondary to a dissection of the anterior division of the right renal artery that was accompanied by hyperreninemia, hyperaldosteronism, and hypokalemia. At presentation in the untreated state, unstimulated plasma renin activity and the serum aldosterone level were markedly elevated. Following right nephrectomy, blood pressure levels normalized without antihypertensive therapy, and plasma renin activity, serum aldosterone and potassium levels normalized. Histologic study of the right renal artery showed an isolated dissection of the anterior branch of the vessel between the muscularis and adventitia that created marked reduction in luminal diameter and renal ischemia. There was no evidence of any other vascular abnormalities, atherosclerosis, or fibromuscular dysplasia. These findings demonstrate that an isolated dissection of a branch of the renal artery may induce profound hyperreninemia and represents a rare, reversible etiology for accelerated hypertension associated with acute encephalopathy.

Conscious sedation for imaging and interventional studies.

Some radiology patients may need medication to decrease anxiety and control pain. In this comprehensive article, the authors describe quality care for patients receiving conscious sedation, effective ways of delivering this service and detailed descriptions of the conscious sedation program at a northeastern university hospital. A valuable chart of recommended drugs, dosages, considerations and possible side effects is included.

Familial band heterotopias simulating tuberous sclerosis.

We report the clinical and neuroimaging findings of a mother and daughter with seizure disorders and band heterotopias seen on magnetic resonance imaging studies. These clinicoradiologic findings simulate those for a diagnosis of tuberous sclerosis complex. Clinicians should be aware of this migrational anomaly and its neuroimaging characteristics, as well as the potential for this specific migrational anomaly to be genetically transmitted.

Neurofibromatosis type 1: magnetic resonance imaging findings.

The purpose of this study was to determine the locations and characterize the types of brain abnormalities noted on brain magnetic resonance imaging in patients with probable and definite neurofibromatosis type 1. Patients with definite neurofibromatosis type 1 (n = 17) were studied when clinically indicated, and patients with probable neurofibromatosis type 1 (n = 9) were studied to evaluate for asymptomatic optic pathway glioma. Of the 26 patients evaluated, 14 (53%) had high-intensity signal abnormalities and 11 (42%) had significant structural abnormalities. Subsequent clinical follow-up has confirmed conversion to a definite neurofibromatosis type 1 diagnosis in three of the four cases of probable neurofibromatosis type 1 who had high-intensity signal abnormalities. The most common locations of high-intensity signal lesions were in the globus pallidus of the basal ganglia and cerebellar white matter. Tortuous or thickened optic nerves and/or optic chiasm were seen in eight cases. Brain magnetic resonance imaging scans frequently reveal high-intensity signal lesions and structural abnormalities in selected patients with both probable and definite neurofibromatosis type 1. These findings may allow for a definitive diagnosis in clinically probable cases.

Human gallbladder morphology after gallstone dissolution with methyl tert-butyl ether.

The effects of methyl tert-butyl ether exposure on the human gallbladder in five patients who were treated for gallstones by contact dissolution is described. Two patients underwent cholecystectomy within 1 week of methyl tert-butyl ether treatment, one patient 2 weeks after, another 10 weeks after, and one 12 weeks after. Indications for cholecystectomy were bilirubinate stones (resistant to methyl tert-butyl ether), catheter dislodgement, bile leakage, and gallstone recurrence (2 patients). Gallstones were dissolved completely in three patients, there was approximately 50% stone reduction in one patient, and no dissolution occurred in the fifth patient. Each gallbladder was examined grossly and histologically. Electron microscopic evaluation was performed in one cases. Typical inflammatory findings of chronic cholecystitis were observed in each gallbladder and were most conspicuous in the submucosa; the mucosal and serosal surfaces were intact. Mild acute inflammatory changes were noted in the submucosa in the two patients with the shortest interval between methyl tert-butyl ether administration and cholecystectomy. There were no ulcerations in the mucosa and no unusual wall thickening or fibrosis in any patient. These observations support the safety of methyl tert-butyl ether perfusion in the human gallbladder; the mild acute changes may be a transient and reversible phenomenon.

Adrenocorticotropin-independent bilateral macronodular adrenal hyperplasia: an unusual cause of Cushing's syndrome.

Inappropriate ACTH secretion with bilateral diffuse or macronodular adrenal hyperplasia is the most common cause of Cushing's syndrome. This report describes a patient with Cushing's syndrome and feminization due to ACTH-independent bilateral macronodular adrenal hyperplasia. A 47-yr-old black man presented with Cushingoid features, diabetes mellitus, hypertension, impotence, and gynecomastia. Urinary cortisol and 17-hydroxycorticosteroid excretion were 94 nmol/mmol creatinine (normal, less than 32) and 5.8 mumol/mmol creatinine (normal, 0.6-3.6), respectively. Both decreased by less than 30% after administration of dexamethasone (8 and 16 mg/day), and urinary 17-hydroxycorticosteroid excretion did not increase after metyrapone (750 mg, orally, every 4 h for six doses). Plasma ACTH was undetectable (less than 1 pmol/L) and was not stimulated by administration of metyrapone or ovine CRH. Serum testosterone was 5.2 nmol/L (normal, 7-30), FSH was 5 U/L (normal, 3-18), LH was 2.8 U/L (normal, 1.5-9.2), and estrone was 767 pmol/L (normal, 55-240). Both adrenal glands were enlarged, with a total weight of 86 g (normal, 8-10), and contained multiple nodules (diameter, greater than 0.5 cm) composed of two active cell types, one of which was also observed between the nodules. Cushing's syndrome with feminization due to ACTH-independent bilateral macronodular adrenal hyperplasia is an unusual process of unknown etiology that should be included with the other known causes of Cushing's syndrome.