Doppler Ultrasound Flow Detector Used in Temporal Artery Biopsy James S.
\s=b\ A can
be
Kelley,
MD
Doppler ultrasound flow detector helpful in performing a temporal
The anatomical location of the arteries can be traced on each side of the patient's head during the preoperative stage, and the flow pattern can be compared with the findings on simple palpation. Selection of a vessel for biopsy may thus be influenced. The detector can also be used under sterile conditions to locate the artery when the injection of local anesthesia has made palpation more difficult, thereby facilitating dissection of an adequate specimen.
artery biopsy.
(Arch Ophthalmol 96:845-846, 1978)
of the
temporal artery is simple procedure that is carried out under local anesthesia, and it is often done without admitting the patient to a hospital. Occasionally however, prolonged dissection is re¬ quired, and in some instances, the specimen obtained is insufficient for pathologic study. An ultrasonic flow meter can be a useful adjunct in potentially difficult cases. Preopera¬ tively, this allows the surgeon to
Biopsy usually
a
become familiar with the anatomy of the temporal vessels, thus supple¬ menting the usual examination by Accepted for publication Sept 6, 1977. From the Wilmer Ophthalmological Institute, The Johns Hopkins Hospital, Baltimore. Reprint requests to 14 W Mount Vernon PI, Baltimore, MD 21201 (Dr Kelley).
alone. The selected biopsy site can then be approached with confidence. The biopsy is then carried out according to standard tech¬ niques.1 The probe can again be applied under sterile conditions dur¬ ing the operation to facilitate dissec¬ tion when the tissues are fatty, edematous, or distorted by the local
palpation
-
injections.
Localization of the artery by ultra¬ sound is facilitated by the Doppler effect. The Doppler ultrasound probe has two transducers. One, when stim¬ ulated by an electric current, emits a continuous wave of ultrasound ener¬ gy. The sound is reflected from the tissue interfaces and received by the second transducer. If the tissues are stationary, the reflected sound will have the same frequency as the trans¬ mitted sound. However, if the trans¬ mitted sound strikes moving tissue (RBCs), the frequency of reflected sound will differ from transmitted sound in direct proportion to the rate of motion. Motion toward the trans¬ ducer is of higher frequency, and motion away from the transducer is of lower frequency. The difference be¬ tween transmitted (5 to 10 MHz) and received frequencies can be amplified to give an audible signal. Consequent¬ ly, cyclical changes in flow, such as the arterial pulse, can be heard to cause a corresponding cyclical sound pattern.
The Doppler probes are widely used noninvasive method of assessing arterial flow.34 We have found such probes (Figure) useful in performing as a
temporal artery biopsy.
MATERIALS AND METHODS A review of 24 consecutive temporal was carried out to deter¬ mine the approximate incidence of tech¬ nical difficulties. A Doppler ultrasonic flow meter, which is commonly used by anesthe¬ siologists and vascular surgeons, was then employed prior to and during a separate series of 20 consecutive temporal artery
artery biopsies
biopsies.
One model of Doppler ultrasound device. Note double transducers in probe tip (arrow). Tip size is approximately 1 cm.
Downloaded From: http://archopht.jamanetwork.com/ by a Southern Illinois University - Carbondale User on 06/06/2015
Preoperatively, a generous amount of petrolatum jelly was applied to the skin of the patient to form a contact area for the ultrasound probe near the patient's temple. The
area above the zygoma, between the and the lateral canthus, and superiorly toward the brow was rapidly scanned. Since an unmistakable pulsatile, swishing sound is heard as the probe passes over an artery, the course of the vessels could be marked with dye or small pieces of tape. Photographs were then taken for a perma¬ nent record. The opposite side was exam¬ ined in the same fashion. The ultrasound findings were compared with the simple palpation of the vessels. During surgery, the sterilized probe was applied directly to the wound. The instru¬ ment can also be used with a sterile plastic cover in which contact jelly is included, although the sensitivity is somewhat reduced. Ultrasound contact was made with irrigation solutions. The direction of further dissection could be guided by the same pulsatile sound. Finally, when the vessel is exposed the arterial nature of the flow can be confirmed by reapplying the
ear
Doppler meter.
RESULTS In reviewing the first set of tempo¬ ral artery biopsies (those made with¬ out the flow meter), most seemed to proceed smoothly. In three cases, however, the procedure lasted two hours or more, and in two other cases, the specimen was insufficient. Al¬ though this was a small series with surgery performed by a variety of surgeons, it indicates that some tech¬ nical problems were encountered in roughly 20% of cases. During the second set of biopsies, the preoperative use of the ultrasound flow meter caused no complications and took little (less than ten minutes) time in most cases. The pulse was located in three general areas: (1) in front of the ear just above the zygoma, (2) just above the lateral
canthus, and (3)
over
of functioning ar¬ taken in this series, theo¬ retically, the Doppler probe can be used to define a segment of vessel that is nonpulsatile. During the biopsy procedure, the
the temporal
biopsy specimens
near
were
portion of the frontal bone
the the
normal hairline. This last area was most common site of biopsy. There were at least five instances in which a pulse could not be palpated, but in which a clear pulse could be heard with the flow meter. In many other cases, the pulse was more easily or primarily detected with the flow meter. With care, a complete outline of the arterial circulation could be constructed. During surgery, although the large diameter of the tip did not allow pinpoint accuracy, the general direction of the vessel could always be determined. There were two cases in which the pulse, easily located just prior to the injection of local anesthe¬ sia, seemed to disappear with the injection of a solution that contained high dilutions of epinephrine hydro¬ chloride. This was found by palpation, ultrasound, and direct visualization. The time that was taken for the biopsy itself was always less than one hour, and the total operating time was more than one hour in only five cases.
COMMENT
The
Doppler technique, as an to temporal artery biopsy, may be extremely useful to the surgeon. It supplements his informa¬ adjunct
tion about the exact location of the vessel and supports his knowledge of the usual anatomy of the artery1 and his examination of the patient by palpation. The skin of many patients who require biopsy is very thin with prominent vessels. Here, the ultra¬ sound may be superfluous. In others, however, the skin is thicker and the arteries small and difficult to palpate. In these cases, the ultrasound can be particularly useful. Although only
teries
artery, though easily palpated before,
may become difficult to locate because edema, hemorrhage, or injection of epinephrine given for local effect. The probe can speed the dissection by indi¬ cating the direction of the arterial pulse. Because of the size of the trans¬ ducer, the accuracy is not absolute. It
of
does, however, indicate a fruitful area for exploration. An interesting additional finding in applying the Doppler technique at surgery was the apparent, complete loss of pulse in patients following the injection of local anesthesia that
contained 1:100,000 epinephrine hy¬ drochloride. This was transient, ten to 15 minutes at the most. It had no ill effects locally and may even aid the preliminary dissection. However, it is interesting to speculate on how such flow changes may affect the eye, when epinephrine is used in the retro¬ bulbar local anesthesia for elderly patients. When the arteries are al¬ ready partially compromised, there may be at least a transient decrease in
perfusion.
References 1. Cohen DN, Smith TR: Skip areas in temporal arteritis: Myth vs fact. Trans Am Acad Ophthalmol Otolaryngol 78:772-783, 1974. 2. Brennan J, McCrary JA: Diagnosis of superficial temporal arteritis. Ann Ophthalmol
9:1125-1129, 1975.
3. Hyman BN: Doppler sonography: A bedside noninvasive method for assessment of carotid artery disease. Am J Ophthalmol 77:227-231, 1974. 4. LoGerfo FW, Mason GR: Directional Doppler studies of supraorbital artery flow in internal carotid stenosis and occlusion. Surgery 76:723\x=req-\ 728, 1974.
Downloaded From: http://archopht.jamanetwork.com/ by a Southern Illinois University - Carbondale User on 06/06/2015
\s=b\ A can
be
Kelley,
MD
Doppler ultrasound flow detector helpful in performing a temporal
The anatomical location of the arteries can be traced on each side of the patient's head during the preoperative stage, and the flow pattern can be compared with the findings on simple palpation. Selection of a vessel for biopsy may thus be influenced. The detector can also be used under sterile conditions to locate the artery when the injection of local anesthesia has made palpation more difficult, thereby facilitating dissection of an adequate specimen.
artery biopsy.
(Arch Ophthalmol 96:845-846, 1978)
of the
temporal artery is simple procedure that is carried out under local anesthesia, and it is often done without admitting the patient to a hospital. Occasionally however, prolonged dissection is re¬ quired, and in some instances, the specimen obtained is insufficient for pathologic study. An ultrasonic flow meter can be a useful adjunct in potentially difficult cases. Preopera¬ tively, this allows the surgeon to
Biopsy usually
a
become familiar with the anatomy of the temporal vessels, thus supple¬ menting the usual examination by Accepted for publication Sept 6, 1977. From the Wilmer Ophthalmological Institute, The Johns Hopkins Hospital, Baltimore. Reprint requests to 14 W Mount Vernon PI, Baltimore, MD 21201 (Dr Kelley).
alone. The selected biopsy site can then be approached with confidence. The biopsy is then carried out according to standard tech¬ niques.1 The probe can again be applied under sterile conditions dur¬ ing the operation to facilitate dissec¬ tion when the tissues are fatty, edematous, or distorted by the local
palpation
-
injections.
Localization of the artery by ultra¬ sound is facilitated by the Doppler effect. The Doppler ultrasound probe has two transducers. One, when stim¬ ulated by an electric current, emits a continuous wave of ultrasound ener¬ gy. The sound is reflected from the tissue interfaces and received by the second transducer. If the tissues are stationary, the reflected sound will have the same frequency as the trans¬ mitted sound. However, if the trans¬ mitted sound strikes moving tissue (RBCs), the frequency of reflected sound will differ from transmitted sound in direct proportion to the rate of motion. Motion toward the trans¬ ducer is of higher frequency, and motion away from the transducer is of lower frequency. The difference be¬ tween transmitted (5 to 10 MHz) and received frequencies can be amplified to give an audible signal. Consequent¬ ly, cyclical changes in flow, such as the arterial pulse, can be heard to cause a corresponding cyclical sound pattern.
The Doppler probes are widely used noninvasive method of assessing arterial flow.34 We have found such probes (Figure) useful in performing as a
temporal artery biopsy.
MATERIALS AND METHODS A review of 24 consecutive temporal was carried out to deter¬ mine the approximate incidence of tech¬ nical difficulties. A Doppler ultrasonic flow meter, which is commonly used by anesthe¬ siologists and vascular surgeons, was then employed prior to and during a separate series of 20 consecutive temporal artery
artery biopsies
biopsies.
One model of Doppler ultrasound device. Note double transducers in probe tip (arrow). Tip size is approximately 1 cm.
Downloaded From: http://archopht.jamanetwork.com/ by a Southern Illinois University - Carbondale User on 06/06/2015
Preoperatively, a generous amount of petrolatum jelly was applied to the skin of the patient to form a contact area for the ultrasound probe near the patient's temple. The
area above the zygoma, between the and the lateral canthus, and superiorly toward the brow was rapidly scanned. Since an unmistakable pulsatile, swishing sound is heard as the probe passes over an artery, the course of the vessels could be marked with dye or small pieces of tape. Photographs were then taken for a perma¬ nent record. The opposite side was exam¬ ined in the same fashion. The ultrasound findings were compared with the simple palpation of the vessels. During surgery, the sterilized probe was applied directly to the wound. The instru¬ ment can also be used with a sterile plastic cover in which contact jelly is included, although the sensitivity is somewhat reduced. Ultrasound contact was made with irrigation solutions. The direction of further dissection could be guided by the same pulsatile sound. Finally, when the vessel is exposed the arterial nature of the flow can be confirmed by reapplying the
ear
Doppler meter.
RESULTS In reviewing the first set of tempo¬ ral artery biopsies (those made with¬ out the flow meter), most seemed to proceed smoothly. In three cases, however, the procedure lasted two hours or more, and in two other cases, the specimen was insufficient. Al¬ though this was a small series with surgery performed by a variety of surgeons, it indicates that some tech¬ nical problems were encountered in roughly 20% of cases. During the second set of biopsies, the preoperative use of the ultrasound flow meter caused no complications and took little (less than ten minutes) time in most cases. The pulse was located in three general areas: (1) in front of the ear just above the zygoma, (2) just above the lateral
canthus, and (3)
over
of functioning ar¬ taken in this series, theo¬ retically, the Doppler probe can be used to define a segment of vessel that is nonpulsatile. During the biopsy procedure, the
the temporal
biopsy specimens
near
were
portion of the frontal bone
the the
normal hairline. This last area was most common site of biopsy. There were at least five instances in which a pulse could not be palpated, but in which a clear pulse could be heard with the flow meter. In many other cases, the pulse was more easily or primarily detected with the flow meter. With care, a complete outline of the arterial circulation could be constructed. During surgery, although the large diameter of the tip did not allow pinpoint accuracy, the general direction of the vessel could always be determined. There were two cases in which the pulse, easily located just prior to the injection of local anesthe¬ sia, seemed to disappear with the injection of a solution that contained high dilutions of epinephrine hydro¬ chloride. This was found by palpation, ultrasound, and direct visualization. The time that was taken for the biopsy itself was always less than one hour, and the total operating time was more than one hour in only five cases.
COMMENT
The
Doppler technique, as an to temporal artery biopsy, may be extremely useful to the surgeon. It supplements his informa¬ adjunct
tion about the exact location of the vessel and supports his knowledge of the usual anatomy of the artery1 and his examination of the patient by palpation. The skin of many patients who require biopsy is very thin with prominent vessels. Here, the ultra¬ sound may be superfluous. In others, however, the skin is thicker and the arteries small and difficult to palpate. In these cases, the ultrasound can be particularly useful. Although only
teries
artery, though easily palpated before,
may become difficult to locate because edema, hemorrhage, or injection of epinephrine given for local effect. The probe can speed the dissection by indi¬ cating the direction of the arterial pulse. Because of the size of the trans¬ ducer, the accuracy is not absolute. It
of
does, however, indicate a fruitful area for exploration. An interesting additional finding in applying the Doppler technique at surgery was the apparent, complete loss of pulse in patients following the injection of local anesthesia that
contained 1:100,000 epinephrine hy¬ drochloride. This was transient, ten to 15 minutes at the most. It had no ill effects locally and may even aid the preliminary dissection. However, it is interesting to speculate on how such flow changes may affect the eye, when epinephrine is used in the retro¬ bulbar local anesthesia for elderly patients. When the arteries are al¬ ready partially compromised, there may be at least a transient decrease in
perfusion.
References 1. Cohen DN, Smith TR: Skip areas in temporal arteritis: Myth vs fact. Trans Am Acad Ophthalmol Otolaryngol 78:772-783, 1974. 2. Brennan J, McCrary JA: Diagnosis of superficial temporal arteritis. Ann Ophthalmol
9:1125-1129, 1975.
3. Hyman BN: Doppler sonography: A bedside noninvasive method for assessment of carotid artery disease. Am J Ophthalmol 77:227-231, 1974. 4. LoGerfo FW, Mason GR: Directional Doppler studies of supraorbital artery flow in internal carotid stenosis and occlusion. Surgery 76:723\x=req-\ 728, 1974.
Downloaded From: http://archopht.jamanetwork.com/ by a Southern Illinois University - Carbondale User on 06/06/2015
