Peter H. Arger

Assessment of adrenal gland volume by computed tomography in depressed patients and healthy volunteers: A pilot study

Excessive adrenocortical activation in depression has been postulated to be the result of overactivity of limbic system-hypothalamic function. In contrast, several studies have suggested the possibility that excessive secretion of cortisol might also result, in part, from a heightened adrenocortical responsiveness to adrenocorticotropic hormone (ACTH), or even a mild adrenal hyperplasia. Because computed tomography (CT) may provide a method for assessing an increase in adrenal size, we performed CT scans of the adrenal glands in depressed patients and healthy volunteers, who also received the dexamethasone suppression test. Eight out of 16 patients (50%) had adrenal volumes in excess of the 95th percentile value of the control distribution for adrenal volume. These observations suggest that there may be demonstrable adrenal hypertrophy during depressive illness.

Strategy for Repeat Biopsy of Patients with Prostatic Intraepithelial Neoplasia Detected by Prostate Needle Biopsy

PURPOSE We evaluated the strategy for repeat biopsy of patients with prostatic intraepithelial neoplasia without concurrent carcinoma detected on prostate needle biopsy. MATERIALS AND METHODS Of 1,275 consecutive patients undergoing prostate needle biopsy 61 were identified with prostatic intraepithelial neoplasia but without concurrent prostate carcinoma. Of the 61 patients 53 had undergone repeat biopsy. The medical records, transrectal ultrasound, and operative and pathological reports of these patients were reviewed. RESULTS Repeat biopsy was done in 53 patients with prostatic intraepithelial neoplasia, yielding carcinoma in 15, prostatic intraepithelial neoplasia without carcinoma in 8 and benign tissue in 30. The yield of carcinoma from repeat biopsy of a prostatic intraepithelial neoplasia site was 8.3% (7 of 84 sites). A total of 18 sites of carcinoma was detected by repeat biopsy of a previous random biopsy site (8), a prostatic intraepithelial neoplasia site only (5), a transrectal ultrasound nodule (3), a palpable nodule and prostatic intraepithelial neoplasia site (1), and a transrectal ultrasound nodule and prostatic intraepithelial neoplasia site (1). Carcinoma was as frequently detected by repeat biopsy of a prostatic intraepithelial neoplasia site (6 patients) as by random repeat biopsy (6 patients). CONCLUSIONS Repeat prostate needle biopsy of patients with prostatic intraepithelial neoplasia should include random repeat biopsy and repeat biopsy of transrectal ultrasound abnormalities as well as previous sites of prostatic intraepithelial neoplasia.

Cerebral hemodynamics in preterm infants during positional intervention measured with diffuse correlation spectroscopy and transcranial Doppler ultrasound

Four very low birth weight, very premature infants were monitored during a 12 degrees postural elevation using diffuse correlation spectroscopy (DCS) to measure microvascular cerebral blood flow (CBF) and transcranial Doppler ultrasound (TCD) to measure macrovascular blood flow velocity in the middle cerebral artery. DCS data correlated significantly with peak systolic, end diastolic, and mean velocities measured by TCD (p(A) =0.036, 0.036, 0.047). Moreover, population averaged TCD and DCS data yielded no significant hemodynamic response to this postural change (p>0.05). We thus demonstrate feasibility of DCS in this population, we show correlation between absolute measures of blood flow from DCS and blood flow velocity from TCD, and we do not detect significant changes in CBF associated with a small postural change (12 degrees ) in these patients.

A Review of Breast Ultrasound

Frequent advances in transducer design, electronics, computers, and signal processing have improved the quality of ultrasound images to the extent that sonography is now a major mode of imaging for the clinical diagnosis of breast cancer. Breast ultrasound is routinely used for differentiating cysts and solid nodules with high specificity. In combination with mammography, ultrasound is used to characterize solid masses as benign or malignant. There is growing interest in using Doppler ultrasound and contrast agents for measuring tumor blood flow and for imaging tumor vascularity. Ease of use and real-time imaging capability make breast ultrasound a method of choice for guiding breast biopsies and other interventional procedures. Breast ultrasound is used in many forms. B-mode is the most common form of imaging for the breast, although compound imaging and harmonic imaging are being increasingly applied to better visualize breast lesions and to reduce image artifacts. These developments, together with the formulation of a standardized lexicon of solid mass features, have improved the diagnostic performance of breast ultrasound. Several approaches that are currently being investigated to further improve performance include: (1) computer-aided-diagnosis; (2) the assessment of tumor vascularity and tumor blood flow with Doppler ultrasound and contrast agents; and (3) tissue elasticity imaging. In the future, ultrasound will play a greater role in differentiating benign from malignant masses and in the diagnosis of breast cancer.

Quantitative Vascularity of Breast Masses by Doppler Imaging: Regional Variations and Diagnostic Implications

Seventy‐four biopsy proven breast masses were imaged by color and power Doppler imaging to evaluate vascular pattern of malignant and benign breast masses. The images were analyzed for vascularity. The measurements were made over the entire mass as well as regionally at its core, at its periphery, and in the tissue surrounding it. The surgical specimens were analyzed for microvessel density. The diagnostic performance of Doppler sonographic vascularity indices was evaluated by receiver operating characteristic analysis. The malignant masses were 14 to 54% more vascular than the benign masses. Both types of masses were more vascular by ultrasonography than the tissue surrounding them. Whereas benign masses were 2.2 times more vascular than the surrounding tissue, the malignant masses were 5.0 times more vascular. In a subset of patients the regional vascularity at the core, periphery, and surrounding tissue by Doppler imaging exhibited a strong correlation (R2 > 0.9) with the corresponding histologic microvessel density measurements. Although the malignant masses exhibited a strong gradient in vascularity, core > periphery > surrounding tissue, the benign masses had relatively uniform distribution of vascularity. The area under the receiver operating characteristic curve (A(Z)) for the Doppler indices ranged from 0.56 +/‐ 0.07 to 0.65 +/‐ 0.07. A nonlinear analysis including age‐specific values of Doppler indices improved the diagnostic performance to A(Z) = 0.85 +/‐ 0.06. In conclusion, quantitative Doppler imaging when used in combination with a nonlinear rule‐based approach has the potential for differentiating between malignant and benign masses.

Teaching Medical Students Diagnostic Sonography

The purpose of this pilot project was to train medical students in sonography.

Ultrasonic Detection of Nonopaque Renal Calculi

Four patients with 5 nonopaque renal calculi composed of uric acid were examined by ultrasound. The calculi varied in size from a 1.5 X 1.5-cm intrapelvic stone to a staghorn calculus measuring 4 cm. All stones were satisfactorily imaged by ultrasound, allowing a diagnosis of nephrolithiasis to be made with confidence in each case. In 2 patients with poor excretion on urography, the diagnosis was not suspected prior to the ultrasound examination. The authors feel that ultrasound has great potential value in the investigation of nonopaque filling defects of the renal pelvis and in patients with urographic nonvisualization who have a high risk of uric acid lithiasis.

Duplex Doppler ultrasonography: Noninvasive assessment of penile anatomy and function

E RECTION is a complex hemodynamic event regulated by the tone of smooth muscle composing the cavernous arterioles, venules, and sinusoids. In the flaccid penis baseline ot-adrenergic stimulation maintains the smooth muscle of the cavernous arterioles and corporal sinusoids contracted. Although vascular resistance to inflow is elevated in the flaccid state, venular outflow is unrestricted. Regulation of venous outflow from the penis appears to be a passive phenomenon; venules draining the sinusoidal spaces coallesce into a plexus below the outer fibroelastic tunica of the paired corporal bodies. Egress from the subtunical venular plexus is via emissary veins exiting perpendicularly through the tunica albuginea into the deep dorsal vein or directly via the cavernous and crural veins at the base of the corporal bodies. 1 Erection is initiated by at least three welldocumented neuropharmacologic stimulants2-5: 1. Inhibition or decrease in excitation of postsynaptic or-1 receptors on cavernous and arteriolar muscle. 2. Increasing cholinergic transmission: Acetylcholine acting on postganglionic adrenergic fibers inhibits norepinephrine release. Acetylcholine mediates the release of endothelial relaxant factor, which rapidly diffuses to the smooth muscle of arteriolar walls. 3. Direct nonadrenergic noncholinergic (NANC) transmission: Several substances have previously been considered to be the NANC erection transmitter (vasoactive intestinal peptide, substance P, prostaglandin E, adenosine triphosphate). Nitric oxide is currently believed to be the principal regulator of NANC corporal relaxation; penile smooth muscle relaxation is initiated by intracellular accumulation of cyclic guanosine monophosphate (cGMP). Tumescence follows a decrease in corporal smooth muscle tone and vascular resistance; arterial inflow increases and the corpora sinusoids distend with oxygenated blood. The expanding sinusoids compress the subtunical plexus and restrict venous outflow. Approximately 90% of systemic arterial pressure is transmitted to the corporal bodies as a result of increased arterial inflow and veno-occlusion. Observations of pudendal and cavernous arterial inflows and intracorporal pressures in the animal model reveal that erection can be divided into six phases: flaccid, latent, tumescence, full erection, rigid erection, and detumescence. 6 Figure 1 shows that cavernous nerve stimulation produces erection with intracorporal pressure reaching 100 mmHg during full erection and transiently exceeding 100 mmHg during the rigid phase. Contemporary clinical studies using intracavernous agents (papaverine, phentolamine, prostaglandin El, and vasoactive intestinal peptide) have revealed that impotence is most often organic in origin and predominantly vasculogenic in etiology 7-11 We believe that color duplex Doppler ultrasound (CDDU) following intracorporal vasoactive stimulation is the most reliable and least invasive means of screening for vasculogenic erectile failure and for selecting patients for more invasive tests of pathologic corporal inflow or outflow. The principles, techniques, and most recent criteria for duplex Doppler penile blood flow are reviewed.

The effect of androgen deprivation on the early changes in prostate volume following transperineal ultrasound guided interstitial therapy for localized carcinoma of the prostate

PURPOSE To determine the change in volume of the prostate as a result of neoadjuvant androgen deprivation prior to prostate implant and in the early postimplant period following transperineal ultrasound guided palladium-103 brachytherapy for early-stage prostate cancer. METHODS AND MATERIALS Sixty-nine men received 3 to 6 months of androgen deprivation therapy followed by treatment planning ultrasound followed 4 to 8 weeks later by palladium-103 implant of the prostate. All patients had clinical and radiographic stage T1c-T2b adenocarcinoma of the prostate. A second ultrasound study was carried out 11 to 13 days following the implant to determine the change in volume of the prostate as a result of the implant. The prehormonal and preimplant volumes were compared to the postimplant volume to determine the effect of hormones and brachytherapy on prostate volume. RESULTS The median decrease in prostate volume as a result of androgen deprivation was 33% among the 54 patients with prostate volume determinations prior to hormonal therapy. The reduction in volume was greatest in the quartile of men with the largest initial gland volume (59%) and least in the quartile of men with smallest glands (10%). The median reduction in prostate volume between the treatment planning ultrasound and the follow-up study after implant was 3%, but 23 (33%) patients had an increase in prostate volume, including 16 (23%) who had an increase in volume >20%; 11 of these patients (16%) had an increase in volume >30%. The time course of development and resolution of this edema is not known. The severity of the edema was not related to initial or preimplant prostate volume or duration of hormonal therapy. CONCLUSIONS Prostate edema may significantly affect the dose delivered to the prostate following transperineal ultrasound guided brachytherapy. The effect on the actual delivered dose will be greater when shorter lived isotopes are used. It remains to be observed whether this edema will affect outcome.

Nonuniform attenuation in computed tomography study of the cirrhotic liver.

Diffuse hepatocellular processes are not well imaged by most radiologic modalities. At present, CT has not added significantly to the evaluation of hepatocellular disease, particularly in the cirrhotic liver. The CT patterns of cirrhosis previously described are reviewed, and the pathophysiology of cirrhosis is discussed. In 3 cases, a pattern was seen in cirrhotic livers characterized by nonuniform attenuation with varied response to administration of intravenous contrast agents. With further evaluation of fatty infiltration and cirrhosis, CT may prove helpful in understanding these disease processes.