A comparison of radiation dose to the bulb of the penis in men with and without prostate brachytherapy-induced erectile dysfunction.

PURPOSE: To retrospectively evaluate the relationship between the radiation dose to the bulb of the penis and the development of erectile dysfunction (ED) in patients undergoing permanent prostate brachytherapy without external beam radiation therapy. METHODS AND MATERIALS: Twenty-three men who developed ED after transperineal ultrasound-guided permanent prostate brachytherapy for clinical T1/T2 adenocarcinoma of the prostate gland were paired with 23 similar men who maintained potency after implantation. Potency was defined as an erection sufficient for vaginal penetration. The mean and median follow-up for the entire group was 34.6 +/- 13.7 months and 32.8 months, respectively. Patients were implanted with either (125)I (145 Gy TG-43) or (103)Pd (115 Gy, pre-NIST-99). No patient received external beam radiation therapy either before or after brachytherapy. The bulb of the penis was outlined at 0.5-cm intervals on the Day 0 postimplant CT scan. The radiation dose distribution to the bulb of the penis was defined in terms of the minimal dose delivered to 25%, 50%, 70%, 75%, 90%, and 95% of the bulb (D(25), D(50), D(70), D(75), D(90), and D(95)). RESULTS: The radiation dose delivered to the bulb of the penis in men with postbrachytherapy-induced ED was statistically greater for all evaluated dosimetric parameters (D(25), D(50), D(70), D(75), D(90), and D(95)). Multivariate analysis indicated that dose to the bulb of the penis and patient age at the time of implant were predictive of postimplant ED, whereas choice of isotope had no effect. Among potent patients, 19/23 had D(50) < or = 40% of prescribed minimal peripheral dose, whereas for the impotent patients, 19/23 had D(50) >40% of the minimal peripheral dose. Of the impotent patients, 17 utilized sildenafil, with 15 experiencing a favorable response (88%). CONCLUSION: Our data suggest that prostate brachytherapy-induced impotence is highly correlated with the radiation dose delivered to the bulb of the penis. With Day 0 dosimetric evaluation, the radiation dose delivered to 50% of the bulb of the penis should be maintained at 50 Gy or less to maximize post-treatment potency. Fortunately, the majority of the brachytherapy-induced ED population responds favorably to sildenafil.

Radioactive seed embolization to the lung following prostate brachytherapy.

Over the past decade, prostate brachytherapy has been increasingly utilized as definitive management for early stage carcinoma of the prostate gland. One risk of the procedure is pulmonary seed embolization. In this article we report the incidence and timing of seed migration. Pulmonary embolization of radioactive seeds occurs in approximately 20% of patients undergoing prostate brachytherapy. To date, no acute or delayed detrimental effects have been reported which are attributable to the pulmonary embolization of the seeds; nevertheless, it is imperative that patients and health care providers be cognizant of this possible event.

Seed fixity in the prostate/periprostatic region following brachytherapy.

PURPOSE: Although postoperative dosimetric analyses of prostate brachytherapy are commonly reported, the long-term persistence, or fixity, of seeds implanted in the prostate gland and periprostatic region remains unclear, with only a few reports regarding the loss or migration of the seeds in the implanted region and none which correlate lung embolization to pelvic seed loss. METHODS AND MATERIALS: The study population consisted of 175 consecutive patients implanted with either 125I (95 patients) or 103Pd (80 patients) using a mean of 136 seeds in a modified uniform loading approach to cover a planning volume that was 1.64 times the ultrasound prostate volume. An average of 64% of 125I seeds were embedded in braided vicryl suture, and these seeds were used on the periphery and extra prostatic regions. Following CT-based dosimetric analysis on day 0, all patients had orthogonal plain films of the pelvis obtained from day 0 to day 502, with an average of 2.3 film pairs per patient. Routine diagnostic PA and lateral chest X rays were obtained for 156 patients over the same time period. RESULTS: The mean pelvic seed fixity was greater than 98% throughout the time covered by this study. The seed fixity rates for 125I and 103Pd, although nearly equal, were significantly different up to 60 days post implant. The median 125I seed loss per patient was only 1 seed through 180 days while for 103Pd, the median seed loss was 2 seeds at 28 and 60 days and 3 seeds at 180 days. The fraction of patients experiencing no seed loss decreased from 40% at 28 days to 20% at 180 days for 125I and from 24% to 7% for 103Pd over the same time interval. Patient and treatment parameters closely correlated to local seed loss include the number of seeds implanted, the planning volume, and the number of loose seeds, and for 125I, the fraction of seeds in suture. The fraction of seeds placed outside the gland was not correlated with seed loss. Of the seeds lost from the pelvis, about 10% were found to embolize to the lungs. Among the 156 patients with post-implant chest X rays, the fraction of patients with pulmonary seed embolization was 34/156 (21.8%). Of the 20 patients who had post-implant chest X rays obtained within 14 days of brachytherapy, none had seeds detected in the lungs, while of the 136 patients who had chest X rays obtained greater than 30 days following implantation, 25.0% (34 patients) were noted to have seeds visualized in the lungs. CONCLUSIONS: With a median follow-up of 9 months, 125I seeds embedded in a vicryl suture or 103Pd seeds can be safely implanted in the prostate and periprostatic tissue with a high probability of prostate bed seed fixity and a low incidence of radioactive seed embolization to the lungs.

Relation between CT scan findings and human sense of smell.

Symptom questionnaires were obtained from 106 patients immediately before nasal and sinus computed tomography scans at the Johns Hopkins Outpatient Center. Their scans were analyzed by two otolaryngologists and three neuroradiologists by using a semiobjective rating system of the size and opacity of 36 anatomic areas. Patients estimated their own left and right sense of smell as excellent, diminished, or absent. Results of the data are as follows: (1) There is no correlation between smell ability and size of the nasal and sinus structures. This indicates that there is no gross effect of the bulging of sinuses into the nasal airway; (2) As a rule, opacity of only left-sided anatomic structures was correlated with both left and right sense of smell (p < 0.01). This suggests that our subjects were using their left smell receptors preferentially, to the exclusion of and in place of the right smell receptors; and (3) Total, not partial, opacity of the left olfactory cleft, frontal recess, or ethmoidal infundibulum was correlated with decreased sense of smell. This suggests that these anterior structures in the region of the olfactory cleft do affect airflow, but complete obstruction of these spaces is needed. Possible explanations for the effect of opacified sinuses on the sense of smell include (1) The presence of fluid or thickened mucosa in the sinuses may interfere with perceived olfactory ability by changing nasal airflow patterns or odorant access to receptors; (2) There may be olfactory receptors inside the sinuses; and (3) There may be a relation between the trigeminal receptors in the sinuses and the olfactory system.

Brain capillary telangiectasia: MR imaging appearance and clinicohistopathologic findings.

PURPOSE: To demonstrate the clinical and magnetic resonance (MR) imaging findings of brain capillary telangiectasia and compare them with postmortem specimens. MATERIALS AND METHODS: MR images obtained in and clinical histories of 18 adult patients with a presumed diagnosis of capillary telangiectasia examined within 3 years were retrospectively reviewed. All patients had undergone MR imaging with conventional T1- and T2-weighted spin-echo sequences and gadolinium-enhanced T1-weighted and susceptibility-sensitive gradient-echo (GRE) sequences. No biopsies had been performed. Fourteen patients had undergone clinical and MR imaging follow-up (median, 11 months). Postmortem tissues from three cases of histopathologically confirmed capillary telangiectasia were imaged. RESULTS: All lesions were small, homogeneously enhancing, and hypo- to isointense on T1-weighted images and iso- to slightly hyperintense on proton-density- and T2-weighted images. None was hypointense on proton-density- or T2-weighted images. All lesions showed marked GRE signal loss. None had changed at follow-up. Two patients had multiple classic cerebral cavernous angiomas. The three specimens showed no abnormal susceptibility and contained no hemosiderin at tissue analysis. CONCLUSION: Capillary telangiectasia has mild contrast material enhancement but is otherwise undetectable on conventional MR images. It lacks the "hemosiderin rim" of cavernous angioma and demonstrates increased susceptibility only on GRE images, likely owing to blood oxygen-level-dependent contrast. GRE is essential in diagnosing brain capillary telangiectasia, which could otherwise be misdiagnosed as neoplasia, subacute infarction, or demyelination.

Nasal and paranasal sinus imaging.

Functional endoscopic sinus surgery has become the surgical treatment of choice in many patients with inflammatory sinus disease refractory to medical treatment. Coronal CT scanning is the imaging modality of choice as it provides initial screening, contributes to surgical planning, and provides an operative "roadmap". The authors stress that close cooperation between the radiologist and the surgeon is mandatory both for evaluation and treatment of paranasal disorders.

Cervical spondylosis: three-dimensional gradient-echo MR with magnetization transfer.

PURPOSE: To compare a three-dimensional Fourier transform (3DFT) gradient-echo pulse sequence with magnetization transfer at a short echo time against standard 3DFT gradient-echo technique in the evaluation of cervical spondylosis, specifically addressing the effects of motion and susceptibility artifacts on the dimensions of the neural foramina and contrast at the cerebrospinal fluid (CSF)-spinal cord interface. METHODS: Ten patients with clinically suspected cervical spondylosis were examined with axial MR imaging using both our standard 3DFT gradient-echo sequence and a 3DFT gradient-echo sequence with a short echo time plus magnetization transfer. Two neuroradiologists measured the transverse dimensions of 22 diseased neural foramina and graded the contrast at the CSF-spinal cord interface. RESULTS: Sixteen of 22 affected neural foramina were larger in the transverse dimension when the magnetization transfer technique was used than when the standard 3DFT gradient-echo sequence was used. In 9 of 10 patients superior contrast was seen at the CSF-spinal cord interface on images obtained with the magnetization transfer technique. CONCLUSIONS: In the cervical spine, 3DFT gradient-echo imaging with magnetization transfer improves contrast and sharpness of the CSF-spinal cord interface at short echo times. This results in less exaggeration of the neural foraminal stenosis as compared with that seen with standard 3DFT gradient-echo techniques owing to the diminished effects of motion and susceptibility artifacts.

Primary craniosynostosis: imaging features.

In 1851, Virchow introduced the term craniosynostosis to describe a variety of abnormalities in calvarial growth. These skull deformities are usually apparent in infancy. When an abnormal calvarial configuration is detected, a radiologic evaluation is necessary to characterize the deformity and to guide the corrective surgical procedure. Affected children are believed to have an improved outcome when diagnosis and surgical intervention occur at an early age. CT with three-dimensional reconstruction optimally evaluates the presence and degree of sutural involvement and assesses associated facial and intracranial abnormalities. This pictorial essay illustrates the imaging findings, nomenclature, and associated abnormalities of the various types of primary craniosynostosis.

The hourglass facial deformity as a consequence of orbital irradiation for bilateral retinoblastoma.

We report a case illustrating characteristic facial deformities following irradiation during infancy for bilateral retinoblastoma. CT and MR imaging revealed distinctive features of the resulting "hourglass facial deformity": hypotelorism, enophthalmos, depressed temporal bones, atrophy of the temporalis muscles, and a depressed nasion. This case also displayed premature metopic craniosynostosis and frontal sinus aplasia; these may be additional hallmarks of this deformity.

Optimal CT evaluation for functional endoscopic sinus surgery.

PURPOSE: To evaluate the optimal parameters for the CT examination of patients who are having functional endoscopic sinus surgery. METHODS: CT scanning was performed on two fresh cadaveric heads in the direct coronal plane, varying the section thickness, intersection gap, scanner gantry angle, and amperage. The nasal cavity and paranasal sinuses were examined independently in a blinded fashion by four staff neuroradiologists and a staff otolaryngologist with special attention to 10 anatomic landmarks within the ostiomeatal unit that are considered important for preoperative planning. A score of 0 (nonvisualization/incomplete visualization) or 1 (clear/complete visualization) was assigned to each of these 10 landmarks. Analysis of variance was used in which reader, subject, and side were simultaneously controlled by "blocking." Multiple comparison methods (ie, Bonferroni) were used to compare the different protocols. RESULTS: We found a significant reduction in the delineation, and therefore the perception, of the ostiomeatal unit structures when the section thickness was greater than 5mm, any intersection gap was used, and the gantry angle was greater than 10 degrees from the plane perpendicular to the hard palate. However, a reduction in the radiation exposure from 200 mA to 80 mA did not affect the display of the anatomic landmarks. CONCLUSION: We found the optimal screening CT protocol for the paranasal sinuses to be a section thickness of 3 mm, no intersection gap, and a section angle within 10 degrees from the plane perpendicular to the palate. Also, owing to inherent contrast between air, soft tissue, and bone in the paranasal sinuses, a reduction in the radiation exposure parameter to 80 mA did not affect image quality.

Cavernous sinus hemangioma. Clinical and neuroimaging features.

A patient presented with an isolated left sixth nerve palsy. Magnetic resonance imaging revealed a sharply marginated 3 cm lesion in the left cavernous sinus, which was isointense to gray matter on T1-weighted images, hyperintense on T2-weighted images, and enhanced with paramagnetic contrast material. Cerebral angiography showed a homogeneous blush fed by an enlarged meningohypophyseal artery. The neuroimaging findings were thought to be most consistent with the diagnosis of a cavernous sinus meningioma. At the time of surgery, a vascular mass was encountered, and a biopsy was consistent with a cavernous hemangioma. This report describes the clinical and neuroimaging features of cavernous sinus hemangiomas that may help to differentiate them from other cavernous sinus lesions.

Update on imaging for functional endoscopic sinus surgery.

This article details the imaging modalities available for patients being considered for functional endoscopic sinus surgery. The pertinent radiologic anatomy is reviewed with an emphasis on normal variations. Imaging appearances of inflammatory sinus disease as well as postoperative appearances, including complications, are presented.

Brain imaging in AIDS.

Although central nervous system (CNS) involvement is common in the population with acquired immunodeficiency syndrome, the presenting neurologic signs and symptoms are often vague and nonfocal. This represents a significant diagnostic challenge for the primary care physician. Cross-sectional imaging now plays an important role in the diagnosis of pathologic processes involving the brain in HIV-infected patients. Involvement of the brain with atypical viruses, parasites, fungi, and neoplasms is more prevalent in AIDS patients. On identification of a brain lesion, it is the role of the imager to characterize it in an attempt to provide a limited differential diagnosis. We review the imaging findings of the pathogens that most commonly affect the brain in AIDS patients.

The bovine alveolar macrophage. II. In vitro studies with Pasteurella haemolytica.

Bovine alveolar macrophages were cultured in vitro and challenged with suspensions of live and dead bacteria. These cells showed severe cytotoxic morphological changes and a low rate of phagocytosis after exposure to live Pasteurella haemolytica type I was readily phagocytosed and produced only mild cytotoxic changes.

Pneumonic pasteurellosis of cattle: microbiology and immunology.

Pasteurellosis was investigated under natural conditions by comparing bacterial and viral nasal flora and levels of bacterial and viral antibody in sera and nasal secretions between animals sick with the disease and those that remained well. The animals were classified sick or well on the basis of the levels of body temperature and plasma fibrinogen. The most significant feature of the bacterial flora was the higher frequency of isolation and the numbers of Past. hemolytica in the nasal flora in the first two weeks after shipment. As indicated by the number of animals with serum antibody to PI-3 virus, infection with this virus was active in both sick and well animals, and serologically, the incidence of infection was higher in animals that remained well. Nasal antibody to PI-3 virus was slightly lower in incidence than serum antibody. Examination of untreated fatal cases and animals killed during the experiment suggests that in some animals there may be a relationship between the high numbers of a bacterial species in the nasal passage and infection by that organism in the lung.